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  Free Full Text References 19 Dec 2007


Free Full Text Article[Alveolar osteotomy and rapid orthodontic treatments]
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[Alveolar osteotomy and rapid orthodontic treatments]

Orthod Fr. 2007 Sep;78(3):217-25

Authors: Sebaoun JD, Ferguson DJ, Wilcko MT, Wilcko WM

When combined with orthodontics, selective periodontal decortication has been shown to be clinically effective in eliminating severe malocclusions three to four times more rapidly than conventional orthodontic treatment. Our technique combines surgical scarring of the cortical bone on both labial and lingual sides of the teeth to be moved, with an augmentation graft to increase alveolar volume. Alveolar spongiosa undergoes rapid transformation as the body attempts to heal the wounds to the cortices resulting in marked tissue turnover. The patient is seen every two weeks and most cases are completed within six months of orthodontic treatment. Moreover, this technique significantly expands the scope of treatment in resolving many skeletal problems such as openbites and severe maxillary constrictions, conditions typically relegated to orthognathic surgery. Clinical outcomes research has shown that the immediate post treatment results settle better during retention and that the long term results become more stable. These facts are likely due to the high tissue turnover induced by decortication as well as the thicker cortical bone resulting from the augmentation grafting.

PMID: 17878040 [PubMed - indexed for MEDLINE]


Free Full Text ArticleMaxillary canine impactions related to impacted central incisors: two case re...
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Maxillary canine impactions related to impacted central incisors: two case reports.

J Contemp Dent Pract. 2007;8(6):72-81

Authors: Bayram M, Ozer M, Sener I

AIM: The purpose of this case report is to describe the combined surgical and orthodontic treatment of two cases with an impacted maxillary central incisor and canine in the same quadrant and to discuss the causal relationship between them. BACKGROUND: The most common causes of canine impactions are usually the result of one or more factors such as a long path of eruption, tooth size-arch length discrepancies, abnormal position of the tooth bud, prolonged retention or early loss of the deciduous canine, trauma, the presence of an alveolar cleft, ankylosis, cystic or neoplastic formation, dilaceration of the root, supernumerary teeth, and odontomas. Although impaction of the maxillary central incisor is almost as prevalent as impacted canines its etiology is different. The principal factors involved in causing the anomaly are supernumerary teeth, odontomas, and trauma. REPORTS: Case #1: A 10.5-year-old girl in the early mixed dentition stage presented with a chief complaint of the appearance of her anterior teeth. She had a Class I skeletal pattern and a history of trauma to the maxillary central incisors at age five with premature exfoliation. Radiographs revealed an impacted upper right central incisor in the region of the nasal floor, delayed eruption of the maxillary permanent central incisor, and the adjacent lateral incisor was inclined toward the edentulous space. Treatment was done in two stages consisting of surgical exposure and traction of the impacted central incisor and fixed orthodontic treatment. Case #2: An 11.5-year-old girl presented for orthodontic treatment with the chief complaint of an unerupted tooth and the appearance of her upper anterior teeth. She was in the late mixed dentition period with a Class III skeletal pattern along with an anterior cross-bite with some maxillary transverse deficiency. The maxillary right canine and central incisor were absent, but the maxillary right deciduous canine was still present. Treatment included arch expansion followed by surgical exposure and traction of the impacted teeth and fixed orthodontic treatment. SUMMARY: This case report provides some evidence of a significant environmental influence of an impacted maxillary central incisor on the path of eruption of the ipsilateral maxillary canine. When an impacted maxillary central incisor exists, the maxillary lateral incisor's root might be positioned distally into the path of eruption of the maxillary canine preventing its normal eruption. Ongoing assessment and early intervention might help to prevent such adverse situations from occurring.

PMID: 17846674 [PubMed - indexed for MEDLINE]


Free Full Text ArticleMorphological study on quadruplets by cephalometric and model analyses.
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Morphological study on quadruplets by cephalometric and model analyses.

Bull Tokyo Dent Coll. 2007 Feb;48(1):19-26

Authors: Shino T, Kawabata K, Nojima K, Nishii Y, Sueishi K, Yamaguchi H

Clarifying the genetic factors involved in maxillofacial growth and development is very important in orthodontic treatment planning and prognosis. However, few dental studies have examined multiple births. The present orthodontic evaluation was conducted using orthodontic data from a set of quadruplets. Orthodontic evaluation was performed on a set of quadruplets (1 girl and 3 boys) aged 9 years and 7 months at the initial visit. Although all 4 children weighed only about 1,400 g each at birth, height and body weight subsequently normalized. Mean skeletal age of the quadruplets was 10 years and 2 months, about 6 months ahead of their calendar age. In all 4 children, facial profile was mostly symmetrical and convex. Intraoral findings showed a Hellman's dental age of IIIA, together with spacing of the upper anterior teeth. Both overbite and overjet were 5-7 mm, and mesial step of the terminal plane was noted. Model analysis showed that tooth materials were on the large side, while arch width was narrow. Cephalometric analysis revealed that the ANB of the first- and fourth-born children was 6 degrees , and skeletal maxillary protrusion due to mandibular retrusion was diagnosed. The second- and thirdborn children exhibited no marked skeletal abnormalities.

PMID: 17721063 [PubMed - indexed for MEDLINE]


Free Full Text ArticleMaxillary corticotomy and extraoral orthopedic traction in mature teenage pat...
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Maxillary corticotomy and extraoral orthopedic traction in mature teenage patients: a case report.

J Contemp Dent Pract. 2007;8(5):76-84

Authors: Pelo S, Boniello R, Gasparini G, Longobardi G

AIM: The authors' propose to combine the reverse pull headgear with a Delaire type face mask and a maxillary corticotomy to treat a Class III non-growing patient with maxillary retrusion. The aim of this report is to present two cases in which this treatment strategy was successful. BACKGROUND: Several studies suggest the majority of Class III dento-skeletal malocclusions have components of maxillary retrusion. Early treatment of these patients with maxillary protraction devices have shown promising results. Facemask therapy has some important limits. Most important is the optimal timing of treatment between the ages of six to ten years. Closure of the maxillary suture occurs as a child ages which results in an increase of maxillary resistance to protraction. REPORT: A proposed therapy carried out in orthodontic and surgical phases was used in the treatment of two young patients. They were both beyond the optimal age range for the application of the orthopedic device (a girl 15 years old and a boy 16 years old), however, they had not reached the necessary skeletal maturity for orthognathic surgery. SUMMARY: The described technique has the advantage of being quick and easy to perform with a low surgical risk yielding satisfactory results after 15-20 days of therapy instead of the six to nine months associated with traditional procedures.

PMID: 17618333 [PubMed - indexed for MEDLINE]


Free Full Text ArticleTreatment effects of occipitomental anchorage appliance of maxillary protract...
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Treatment effects of occipitomental anchorage appliance of maxillary protraction combined with chincup traction in children with Class III malocclusion.

J Formos Med Assoc. 2007 May;106(5):380-91

Authors: Lin HC, Chang HP, Chang HF

BACKGROUND/PURPOSE: Little information related to the treatment effects of the occipitomental anchorage (OMA) appliance of maxillary (Mx) protraction combined with chincup traction is available. The aim of this study was to investigate the treatment effects of the OMA orthopedic appliance on patients with Class III malocclusion. METHODS: Pretreatment and post-treatment cephalometric records of 20 consecutively treated patients with Class III malocclusions were evaluated and compared with a matched sample of untreated Class III control subjects. RESULTS: The OMA appliance is effective for correcting skeletal Class III malocclusion in growing children. The treatment effects of this orthopedic appliance were considered to be from both skeletal and dentoalveolar changes. The skeletal effects were mainly obtained by stimulating forward growth of the Mx complex with negligible rotation of the Mx plane and restraining forward advancement of the mandible (Mn) with backward and downward rotation of the Mn plane. The observed dentoalveolar effects were mostly due to the labial tipping movement of the Mx incisors. CONCLUSION: Our results suggest that the OMA orthopedic appliance can correct the mesial jaw relationship and negative incisal over jet. This appliance is effective for correcting skeletal Class III malocclusion with both midface deficiency and Mn prognathism in growing children.

PMID: 17561473 [PubMed - indexed for MEDLINE]


Free Full Text ArticlePressure from the lips and the tongue in children with class III malocclusion.
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Pressure from the lips and the tongue in children with class III malocclusion.

J Zhejiang Univ Sci B. 2007 May;8(5):296-301

Authors: Ruan WH, Su JM, Ye XW

OBJECTIVE: To discuss possible relationships between class III malocclusion and perioral forces by measuring the pressure from the lips and the tongue of children with class III malocclusion. METHODS: Thirty-one children with class III malocclusion were investigated and their perioral forces were measured at rest and during swallowing under natural head position by a custom-made miniperioral force computer measuring system. RESULTS: The resting pressures exerted on the labial side and palatine side of the upper left incisor, as well as the labial side and lingual side of the lower left incisor, were 0 g/cm(2), 0 g/cm(2), 0.57 g/cm(2) and 0.23 g/cm(2), respectively. Correspondingly, the swallowing forces were 2.87 g/cm(2), 5.97 g/cm(2), 4.09 g/cm(2) and 7.89 g/cm(2), respectively. No statistical difference between muscular pressure and gender existed. During swallowing, the lingual forces were significantly higher than the labial forces (P<0.01), however, at rest there was no significantly different force between these two sides. Compared to the normal occlusion patients, children with class III malocclusion had lower perioral forces. The upper labial resting forces (P<0.01), the lower labial resting forces (P<0.05) and all the swallowing pressures from the lips and the tongue (P<0.01) showed statistical differences between the two different occlusion conditions. Meanwhile, no significant difference was found for the resting pressure from the tongue between class III malocclusion and normal occlusion. CONCLUSION: Patients with class III malocclusion have lower perioral forces and this muscle hypofunction may be secondary to the spatial relations of the jaws. The findings support the spatial matrix hypothesis.

PMID: 17542055 [PubMed - indexed for MEDLINE]


Free Full Text Article[Changes in mastication efficiency before and after orthodontic treatment of ...
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[Changes in mastication efficiency before and after orthodontic treatment of adult skeletal angle III malocclusion]

Shanghai Kou Qiang Yi Xue. 2006 Dec;15(6):578-80

Authors: Yang Q, Fan CH, Liu XQ, Chen J

PURPOSE: To evaluate the changes of mastication efficiency pre- and post-treatment in adult skeletal Angle III malocclusion, and to analyze the effect of malocclusion on mastication efficiency. METHODS: Masticatory efficiency was analyzed in 60 patients with adult skeletal Angle III malocclusion pre- or post-orthodontic treatment and 30 adults with normal occlusion as controls. Masticatory efficiency was measured by means of a spectrophotometer using Gelatin. SPSS 10.0 software package was used for Student's t test and step-wise regression. RESULTS: (1) Significant difference of masticatory efficiency was found among the three groups (P < 0.001). Multiple comparision showed significant difference among pre-treatment group, post-treatment group and normal controls (P < 0.05). (2) Step-wise regression results suggest that overjet and mandibular prognathism were closely related to masticatory efficiency in both pre- and post-treatment group. CONCLUSION: Orthodontic therapy can improve masticatory function in patients with malocclusion.

PMID: 17533706 [PubMed - in process]


Free Full Text ArticleEffects of activator and high-pull headgear combination therapy: skeletal, de...
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Effects of activator and high-pull headgear combination therapy: skeletal, dentoalveolar, and soft tissue profile changes.

Eur J Orthod. 2007 Apr;29(2):140-8

Authors: Mar&#x15F;an G

The aim of this study was to evaluate skeletal, dentoalveolar, and soft tissue profile changes with activator and high-pull headgear combination therapy in patients with Class II malocclusions caused by maxillary prognathism and mandibular retrognathism. The subjects, all in the mixed dentition, were selected from a single centre and were divided into two groups: 28 patients were treated with an incisor double capping activator and a high-pull headgear combination appliance (13 girls, 15 boys mean chronological age 11.7 +/- 1.2 years, skeletal age 12.1 +/- 1.4 years) and an untreated group of 28 subjects (14 girls, 14 boys mean chronological mean age 11.9 +/- 1.1 years, skeletal age 12.3 +/- 1.3 years). The skeletal, dentoalveolar, and soft tissue profile changes that occurred were compared on lateral cephalograms taken before treatment (T0) and after 1.1 +/- 0.3 years when the combination appliance was removed (T1). In the control group, the radiographs were obtained at the start (T0) and after an observation period 1.2 +/- 0.4 years (T1). Statistical analysis was undertaken with Wilcoxon's ranked-sum test for intra-group comparisons and differences between groups with t-test and Bonferroni's test at a level of significance of P < 0.05. Activator and high-pull headgear combination treatment in these growing patients resulted in a correction of the skeletal Class II relationship (ANB -3.4 degrees), a restriction of maxillary growth (SNA -2.0 degrees, OLp-A -2.3 mm), an advancement of the mandibular structures (SNB +2.6 degrees, FH-NPg +2.3 degrees, OLp-B +2.7 mm, OLp-Pg +2.2 mm), an increase in lower face height (ANS-Me +3.9 mm), a correction of the overjet (-5.4 mm), an improvement in overbite (-2.2 mm), uprighting of the maxillary incisors (U1-FH -5.3 degrees, OLp-U1 -2.5 mm), protrusion of the mandibular incisors (IMPA +2.0 degrees, OLp-L1 +2.7 mm), and a correction of the dental Class II malocclusion (OLp-L6 +3.5 mm). The soft tissue profile changes were a correction of facial convexity (G'-Sn-Pg' angle 2.3 degrees, Mlf-Li-x-axis angle 9.1 degrees), and an increase in lower antero-posterior (Mlf-y-axis 5.6 mm, Pg'-y-axis 5.3 mm), and lower vertical (Sls-x-axis 3.8 mm, Pg'-x-axis 3.8 mm, Me'-x-axis 5.1 mm) soft tissue dimensions. The mentolabial fold depth (Mlf-E line) also significantly decreased, -0.8 mm in the treated group. The activator and high-pull headgear combination appliance was effective in treating growing patients with maxillary prognathism, mandibular deficiency, and facial convexity by a combination of skeletal and dentoalveolar changes and improvement in the soft tissue facial profile.

PMID: 17488997 [PubMed - indexed for MEDLINE]


Free Full Text ArticleOsteochondroma of the mandibular condyle: literature review and report of a c...
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Osteochondroma of the mandibular condyle: literature review and report of a case.

J Contemp Dent Pract. 2007;8(4):52-9

Authors: Ribas Mde O, Martins WD, de Sousa MH, Zanferrari FL, Lanzoni T

AIM: The intent of this report is to present a brief review of the literature on osteochondroma and to present a case involving the surgical removal and replacement of a major portion of the condyle and angle of the mandible using free autogenous mandibular bone. BACKGROUND: While osteochondroma is the most common tumor of skeletal bones, it is relatively uncommon in the jaws occurring at the condyle or the tip of the coronoid process. This benign cartilage-capped growth is usually discovered incidentally on radiographic examination or on palpation of a protruding mass in the affected area. Malocclusion and progressive facial asymmetry are common findings in most cases of condylar osteochondroma. REPORT: A case of a 29-year-old woman with an osteochondroma of the mandibular condyle is presented. Surgical treatment was tumor resection, grafting, and reshaping of the mandibular angle and ramus. As this lesion is usually asymptomatic and discovered incidentally on radiographic examination, the general practitioner usually is the first professional to make the diagnosis. SUMMARY: Condylectomy cannot be recommended as routine in all cases.37 Common surgical treatments include condylectomy and reconstruction.24 If the tumor involves only a limited area of the condylar surface, then preservation of the remaining portion of the condyle and reshaping should be done. Reasons for not taking such a conservative approach are the possibilities of malignancy and the risk of recurrence. In this case report the extraoral vertical ramus osteotomy, associated with free autogenous mandibular bone, presented several advantages.

PMID: 17486187 [PubMed - indexed for MEDLINE]


Free Full Text ArticleA controlled clinical trial of the effects of the Twin Block and Dynamax appl...
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A controlled clinical trial of the effects of the Twin Block and Dynamax appliances on the hard and soft tissues.

Eur J Orthod. 2007 Jun;29(3):272-82

Authors: Lee RT, Kyi CS, Mack GJ

The aim of this controlled trial was to identify and quantify skeletal, soft tissue and dental changes during treatment, and immediately post-treatment with Twin Block (TB) or Dynamax appliance using the techniques of three-dimensional (3D)optical surface laser scanning, cephalometric, and clinical measurements. Sixty-two Caucasian subjects, 36 males aged 11-14 years and 26 females aged 10-13 years were enrolled in the study. The patients were placed in two groups, matched for gender and age and subsequently allocated randomly for treatment with either a TB or Dynamax appliance. Active treatment lasted 9 months followed by 3 months' post-treatment observation. Laser scanning and clinical measurements were taken at 3-monthly intervals and final cephalometric records after 12 months. Statistical analysis was performed using Wilcoxon's matched-pairs signed-rank tests. The non-compliance rates were the same for both groups (9 per cent), but a greater incidence of breakages was found in the Dynamax group. The TB was found to produce slightly more antero-posterior skeletal change, median ANB reduction, TB=2 degrees, Dynamax 1.1 degree (P=0.006), and similar forward movements of the chin and was associated with larger increases in the vertical facial dimension, median total anterior face height increase; TB=3.2 mm, Dynamax = 2.8 mm (P=0.03). The soft tissue vertical cephalometric increases were 3.6 mm with the TB, 2.0 mm with the Dynamax (P=0.036), and with laser scanning 5.05 and 2.6 mm, respectively, a difference which is likely to be more clinically relevant. The median post-treatment changes in soft tissue pogonion were -0.65 mm in the TB and +0.22 mm in the Dynamax group. The optical surface scanning mark and measure system is a valid method for quantifying soft tissue changes.

PMID: 17456506 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEvaluation of long-term satisfaction with orthodontic treatment for skeletal ...
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Evaluation of long-term satisfaction with orthodontic treatment for skeletal class III individuals.

J Oral Sci. 2007 Mar;49(1):31-9

Authors: Uslu O, Akcam MO

The aim of this study was to investigate the long-term satisfaction rate among skeletal class III patients following orthodontic treatment. Questionnaires were sent to 315 post-retention (between 5 to 22.5 years) patients who had received orthodontic treatment without any type of surgery for the correction of skeletal class III malocclusion. The questionnaire contained 28 questions: 10 regarding orthodontic treatment, 13 regarding satisfaction with orthodontic treatment outcomes, and five regarding psychosocial benefits of orthodontic treatment. The frequency of each variable was calculated and chi-squared test was used to determine gender correlations. The survey response rate was 15.8% (n = 40). Most patients were satisfied with their facial appearance (92.5%) and final esthetic profile (95%). Of the 5% who were dissatisfied with their final profiles, prognathic mandible was given as the reason. Most patients (90%) were satisfied with the overall treatment results. Moreover, patient perceptions of psychosocial benefits of treatment were mainly positive, with the majority (72.5%) stating their social communication had improved following orthodontic treatment. Chi-squared test indicated almost no variations in response by gender. In conclusion, the majority of skeletal class III patients in the long-term post-retention period who had received orthodontic treatment were satisfied with the overall treatment outcome. (J. Oral Sci. 49, 31-39, 2007).

PMID: 17429180 [PubMed - in process]


Free Full Text ArticleTooth size and arch dimension in uncrowded versus crowded Class I malocclusions.
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Tooth size and arch dimension in uncrowded versus crowded Class I malocclusions.

J Contemp Dent Pract. 2007;8(3):45-52

Authors: Poosti M, Jalali T

AIM: The purpose of this investigation was to examine the extent to which arch dimension or tooth size contributes to dental crowding. METHODS AND MATERIALS: Two groups of dental casts were selected. Each group consisted of 30 pairs of dental casts including equal male and female samples. The first group had Class I malocclusions without crowding or spacing. The second group exhibited Class I malocclusions with severe dental crowding (> a 5 mm space deficiency). The following parameters were measured and used to compare the two groups: individual and collective mesiodistal tooth diameters, dental arch length, as well as buccal and lingual dental arch widths in the canine and molar regions. To compare the two groups the Student's t-test with 95% confidence interval was used. RESULTS: Statistically significant differences in both tooth diameters and transverse arch dimensions were found between the two groups. The crowded group was found to have a significantly smaller maxillary arch width and larger tooth size when compared with the uncrowded group. CONCLUSION: The results of this study suggest under equal conditions (a Class I skeletal relationship) tooth size has a greater role in developing dental crowding.

PMID: 17351681 [PubMed - indexed for MEDLINE]


Free Full Text ArticleSurgically assisted rapid maxillary expasion: a preliminar study.
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Surgically assisted rapid maxillary expasion: a preliminar study.

Rev Bras Otorrinolaringol (Engl Ed). 2006 Jul-Aug;72(4):457-61

Authors: do Egito Vasconcelos BC, Caubi AF, Dias E, Lago CA, Porto GG

Surgically assisted rapid maxillary expansion is efficient for the treatment of transverse maxillary deficiencies in skeletally mature patients. AIM: To study two techniques for surgically assisted rapid maxillary expansion: with or without pterygoid plate detachment. MATERIAL AND METHODS: A longitudinal cohort study sample including ten patients aged 18-40 years, with a skeletal transverse discrepancy in the maxilla of more than 4 mm. Two groups were established on a randomized basis, five patients in each group, according to the detachment or absence of detachment of the pterygoid plate. Furthermore, osteotomies of the bilateral zygomatic buttress and the intermaxillary suture were done in both groups. The transverse discrepancy was measured in study models, a posterior-anterior cephalometric radiograph evaluated the superior and inferior zygomatic plane and the inter-tuber distance and an occlusal radiograph evaluated the intermaxillary disjunction in the pre-operative period and 30 days post-operatively. A 7-day period of rest was given after corticotomy before starting expansion with quarter turns once a day. RESULTS: There were no statistically significant differences between pre- and post-operative measurements. CONCLUSION: There are few randomized control trials in literature comparing the two techniques for surgically maxillary expansion. Further studies with a larger sample are required.

PMID: 17143423 [PubMed - indexed for MEDLINE]


Free Full Text ArticleComparison of the headgear activator and Herbst appliance--effects and post-t...
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Comparison of the headgear activator and Herbst appliance--effects and post-treatment changes.

Eur J Orthod. 2006 Dec;28(6):594-604

Authors: Phan KL, Bendeus M, H&#xE4;gg U, Hansen K, Rabie AB

The aim of this study was to evaluate the effects of the headgear activator (HGA) and Herbst appliance during active treatment and retention and at follow-up in children with a skeletal Class II malocclusion. The two groups comprised 16 consecutive male patients (mean age 11.6 +/- 1.42 years) treated with a HGA and 16 male patients (mean age 12.6 +/- 1.13 years) treated with a Herbst appliance and Andresen activator (HAA) sampled from a larger pool using similar selection criteria. Growth data were obtained for the two groups. Lateral cephalograms taken at the start, after 6 months of treatment, after 12 months of active treatment or 6 months of retention, and at the 24-month follow-up were analysed. The total changes over the whole observation period (T0-T3) did not differ significantly between the groups; there was, however, a statistically significant increase in jaw prognathism (P < 0.05) and improvement of the molar relationship (P < 0.05) in the HAA group as compared with the HGA group. During the initial treatment phase (T0-T1), the overall treatment effects were statistically more pronounced in the HAA group than in the HGA group. Despite significant differences in treatment effects and changes between the two devices, there were no significant overall changes at follow-up except for the prognathism, i.e. maxillary prognathism decreased with treatment with the HGA while mandibulars prognathism continued to increase with HAA treatment.

PMID: 17142260 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThe influence of functional orthodontics and mandibular sagittal split advanc...
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The influence of functional orthodontics and mandibular sagittal split advancement osteotomy on dental and skeletal variables--a comparative cephalometric study.

Eur J Orthod. 2006 Dec;28(6):553-60

Authors: Lohrmann B, Schwestka-Polly R, Nägerl H, Ihlow D, Kubein-Meesenburg D

Lateral head films of 200 Class II patients (106 females, 94 males) with a mean pre-treatment age range of 9.9-10.25 years successfully treated with functional orthodontics were analysed before (T1) and after (T2) treatment. The resulting data and findings were compared with lateral head films (T1, T2) of 20 patients (15 females, five males) with a mean pre-treatment age of 25.75 years whose Class II malocclusion and antero-posterior jaw discrepancy had been corrected by a mandibular sagittal split advancement osteotomy. The median and interquartile distances were calculated for every variable, at T1 and T2. The difference between the medians (T2-T1) was analysed using a signed rank test. The changes in scattering (T2-T1) were assessed by means of a F-test. Significant differences regarding the therapeutic influence on skeletal [ANB, Wits, Index, mandibular line-nasal line (ML-NL)], functional (beta', mu), and dental (1-NA degrees , 1-NB degrees ) variables were found. In the group initially treated with functional appliances in order to enhance mandibular prognathism, the antero-posterior (A-P) jaw discrepancy was reduced (ANB, Wits). The vertical skeletal pattern (Index) changed towards a more skeletal open relationship, whereas the ML-NL angle was reduced, which indicates a deepening of the bite. The comparison between biomechanical incisor position analysis (beta', mu) and dental variables (1-NA degrees , 1-NB degrees ) revealed different changes in incisor inclination depending on the type of analysis used. The findings for the dental variables (1-NA degrees , 1-NB degrees ) showed a protrusion of both upper and lower incisors after therapy. The results for the functional variables (beta', mu) showed a retrusion of the upper and a protrusion of the lower incisors. This change in incisor inclination is a dental compensation of the remaining sagittal jaw discrepancy. This effect is most clearly reflected by the functional analysis and the changes of the biomechanical variables beta' and mu. For the orthognathic surgery group, a clear improvement in the dental and skeletal relationship was observed: the skeletal discrepancies in the A-P plane were completely corrected (ANB, Wits) and the inclination of the incisors according to biomechanical and functional aspects was optimized (beta', mu).The alteration in both the Index and ML-NL angle in this group indicated an increase of the open bite components.

PMID: 17142259 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThe effect of tongue appliance on the nasomaxillary complex in growing cleft ...
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The effect of tongue appliance on the nasomaxillary complex in growing cleft lip and palate patients.

J Indian Soc Pedod Prev Dent. 2006 Sep;24(3):136-9

Authors: Jamilian A, Showkatbakhsh R, Boushehry MB

Midfacial deficiency is a common feature of cleft lip and palate patients due to scar tissue of the lip and palate closure procedure. The aim of this study was to evaluate the effectiveness of the physiological force of the tongue to move the maxilla in forward position. This research has been done experimentally by, before and after treatment following up in private practice. Ten patients (6 female, 4 male) with complete bilateral cleft lip and palate were selected. All of them had Cl III malocclusion with maxillary deficiency due to scar tissue of lip and palate surgery. Their age ranged from 7.6 to 9.8 years. All the patients were delivered tongue appliance to transfer the force of the tongue to maxillary complex. The mean observation time was 13+/-2 months to achieve positive overjet. Pre- and post-lateral cephalograms were compared to evaluate the skeletal changes with paired t-test. The results showed that after the application of tongue appliance, normal sagittal maxillomandibular relationship was achieved. SN-ANS angle was increased 1.9+/-1.8 - P < 0.03. This study showed that the tongue appliance could transfer considerable force during rest and swallowing period to the maxilla. This method might be considered to improve the deficient maxilla by means of growth modification and redirect concept.

PMID: 17065780 [PubMed - indexed for MEDLINE]


Free Full Text ArticleTreatment of mandibular prognathism.
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Treatment of mandibular prognathism.

J Formos Med Assoc. 2006 Oct;105(10):781-90

Authors: Chang HP, Tseng YC, Chang HF

Mandibular prognathism (MP) or skeletal Class III malocclusion with a prognathic mandible is one of the most severe maxillofacial deformities. Facial growth modification can be an effective method of resolving skeletal Class III jaw discrepancies in growing children with dentofacial orthopedic appliances including the chincup, face mask, maxillary protraction combined with chincup traction and the Fr&#xE4;nkel functional regulator III appliance. Orthognathic surgery in conjunction with orthodontic treatment is required for the correction of adult MP. The two most commonly applied surgical procedures to correct MP are sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy. Both procedures are suitable for patients in whom a desirable occlusal relationship can be obtained with a setback of the mandible, and each has its own advantages and disadvantages. In bilateral SSRO, the intentional ostectomy of the posterior part of the distal segment can offer long-term positioned stability. This may be attributable to reduction of tension in the pterygomasseteric sling that applies force in the posterior mandible. While various environmental factors have been found to contribute to the development of MP, heredity plays a substantial role. The relative contributions of genetic and environmental components in the etiology of MP are unclear. The recent identification of the genetic susceptibilities to MP constitutes the first step toward understanding the molecular pathogenesis of MP. Further studies in molecular biology are needed to identify the gene-environment interactions associated with the phenotypic diversity of MP and the heterogenic developmental mechanisms thought to be responsible for them.

PMID: 17000450 [PubMed - indexed for MEDLINE]


Free Full Text Article[A study of highpull extraoral traction on the treatment of growing patients ...
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[A study of highpull extraoral traction on the treatment of growing patients with skeletal Class II malocclusion]

Shanghai Kou Qiang Yi Xue. 2006 Aug;15(4):375-7

Authors: You QL, Cai Z

PURPOSE: To evaluate the effect of highpull extraoral traction on growing patients with skeletal Class II malocclusion. METHODS: 11 pairs of cephalograms obtained before and after highpull extra-oral traction treatment were used in this study, treatment changes were measured with Pancherz analysis, and compared with the control group. Independent samples group t test with SPSS 11.0 software package was used for statistical analysis. RESULTS: highpull extra-oral traction had inhibitive effect on forward and downward maxillary growth. Changes on SNA, A-Olp between the two groups were statistically different (P<0.01). Upper molars were moved back (P<0.01). CONCLUSION: highpull extraoral traction had orthopedic effect on the correction of skeletal Class II malocclusion of growing patients, including inhibition of maxillary growth and allowance of fully expression of mandibular growth. Meanwhile, dental-alveolar changes on the vertical and sagittal plane were beneficial to further improvement of the dental and facial appearance of the patients.

PMID: 16955161 [PubMed - in process]


Free Full Text Article[Heritability analysis on skeletal angle III malocclusion]
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[Heritability analysis on skeletal angle III malocclusion]

Shanghai Kou Qiang Yi Xue. 2006 Jun;15(3):269-72

Authors: Wang S, Feng PX, Guo X, Wang XR

PURPOSE: To explore the significance of genetic factor in the pathogenesis of skeletal angle III malocclusion. METHODS: A case-control study of 96 probands, 200 controls and their relatives was performed and the data were analyzed with genetic epidemiologic methods. SPSS11.5 software package was used for Chi-square test. RESULTS: The prevalence rates of skeletal angle III malocclusion in the first-degree relatives and second-degree relatives in the proband group were 9.00% and 1.88%,respectively,which were higher than that in the first-degree relatives in the control group(0.96%). The heritability in the first-degree relatives was 0.74+/-0.092.The results of segregation analysis didn't suggest that skeletal angle III malocclusion followed a pattern of autosomal recessive inheritance. CONCLUSION: Skeletal angle III malocclusion has characteristics of polygenetic disease. Genetic factor might play an important role in the pathogenesis of skeletal angle III malocclusion.

PMID: 16862359 [PubMed - in process]


Free Full Text ArticleComparison of tooth size discrepancies among different malocclusion groups.
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Comparison of tooth size discrepancies among different malocclusion groups.

Eur J Orthod. 2006 Oct;28(5):491-5

Authors: Fattahi HR, Pakshir HR, Hedayati Z

This retrospective investigation was designed to compare tooth size discrepancies among subjects with different skeletal malocclusions in an orthodontic population. The study employed the pre-treatment models of 200 patients (100 males, 100 females, aged from 14 to 20 years) selected from the records of the Orthodontic Department, Shiraz Dental School. The subjects were from four malocclusion groups, Class I, Class II division 1, Class II division 2, and Class III, with the corresponding skeletal characteristics. Each group comprised 50 healthy individuals (25 males, 25 females). The mesio-distal dimensions of teeth were measured using digital electronic callipers (accurate to 0.01 mm) and the Bolton indices were determined. The data were statistically analysed using analysis of variance and Duncan's multiple range test, with the level of significance set at P < 0.05. The results revealed that the mean anterior ratio (79.01) for the whole sample was statistically significantly different from Bolton's (77.2) but no significant difference was found for the overall ratio. The posterior and overall ratios of the Class III malocclusion group were statistically greater than the other malocclusion groups (P < 0.05). The mean anterior ratio of the Class III group was greater than that of the Class II group. However, there was no difference when compared with the Class I malocclusion group. For the two types of Class II malocclusion, no significant ratio differences were observed.

PMID: 16763087 [PubMed - indexed for MEDLINE]


Free Full Text ArticleCorrection of anterior open bite in a case of achondroplasia.
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Correction of anterior open bite in a case of achondroplasia.

Indian J Dent Res. 2005 Oct-Dec;16(4):159-66

Authors: Karpagam S, Rabin K, George M, Santhosh K

Treatment planning for patients with skeletal deformities is often considered challenging. This article reports a female patient with achondroplasia who presented with severe maxillary retrognathism and vertical excess along with anterior open bite. The clinical and cephalometric findings of the patient are detailed here. The treatment plan consisted of modified anterior maxillary osteotomy for simultaneous vertical and sagittal augmentation along with orthodontic intervention. The course of surgical-orthodontic treatment and the results are presented. This treatment is to be followed by correction of vertical maxillary excess after completion of growth. This paper concludes that the dentoalveolar component of a skeletal deformity can be handled independent of the craniofacial management.

PMID: 16761710 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThe Dynamax system: a new orthopaedic appliance and case report.
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The Dynamax system: a new orthopaedic appliance and case report.

J Orthod. 2006 Jun;33(2):78-89

Authors: Bass NM

The Dynamax appliance is a treatment modality for the correction of the Skeletal II malocclusion characterized by a mandibular retrusion. Progressive mandibular advancement, maxillary expansion, control of maxillary growth, incisor torque and control of vertical facial development are incorporated into a two-part appliance. The design facilitates laboratory construction, clinical handling and patient acceptability. A prefabricated spring module forms the basis of the appliance, allowing both maxillary expansion and mandibular advancement. An easily adjustable progressive forward position of the lower jaw makes a construction bite unnecessary. The spring module provides most of the structure of the appliance so that minimal acrylic is required and the appliance is fully contained within the freeway space. Contact between the upper and lower parts of the appliance occurs posteriorly in the lingual sulcus. Here the depth permits an extended vertical contact, to maintain a protrusive mandibular position throughout the range of mandibular opening, including during sleep. The lower portion of the appliance may be fixed or removable and multibracket treatment can be carried out in one or both arches at the same time as the orthopaedics.

PMID: 16751429 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEffects of functional orthodontic appliances in the correction of a primary a...
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Effects of functional orthodontic appliances in the correction of a primary anterior crossbite--changes in craniofacial morphology and tongue position.

Eur J Orthod. 2006 Aug;28(4):373-7

Authors: Onodera K, Niikuni N, Yanagisawa M, Nakajima I

Chin caps have been used for the correction of primary anterior crossbites, but previous studies of the treatment effects have highlighted problems such as pressure on the temporomandibular joint (TMJ). Therefore, to reduce pressure on the TMJ, a functional orthodontic appliance, the Yanagisawa Class III (YC3) shield was developed to improve the overjet in the primary dentition. The aim of this study was to determine the treatment effects of the YC3 in correcting a primary anterior crossbite compared with a chin cap. The pre- and post-treatment lateral cephalograms of 10 patients (5 male, 5 females) and 10 treated with a YC3 (5 males, 5 females) were compared in relation to craniofacial morphology and tongue position [the YC3 was used from 51 months of age +/- 7 months to 74 months of age +/- 12 months (i.e. for 23 +/- 9 months) and the chin cap from 53 months of age +/- 2 months to 75 months of age +/- 1 month (i.e. for 22 +/- 5 months)]. A Mann-Whitney U-test was used to determine any statistical differences. The YC3 group showed significantly higher values for gonial angle and U1 to SN (P < 0.05), and significantly lower values for interincisal and tongue position (P < 0.05), compared with the chin cap group. The results indicate that the use of the YC3 not only improves overjet, but also changes the tongue position. The findings also suggest that the YC3 results in functional effects on the skeletal system during the mid-growth period.

PMID: 16731543 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEvaluation of maxillary protraction and fixed appliance therapy in Class III ...
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Evaluation of maxillary protraction and fixed appliance therapy in Class III patients.

Eur J Orthod. 2006 Aug;28(4):383-92

Authors: Arman A, Ufuk Toygar T, Abuhijleh E

The aim of this study was to examine the dentofacial changes in Class III patients treated with fixed appliances subsequent to rapid maxillary expansion (RME) and facemask therapy. The material consisted of the cephalograms and hand-wrist films of 14 (9 girls, 5 boys) skeletal Class III and 15 (10 girls, 5 boys) untreated subjects obtained at the beginning of treatment/observation T1, immediately after orthopaedic therapy T2, and at the end of the observation period T3. The mean pre-treatment/control ages were approximately 11.5 years and the observation period was 3 years T2-T1: 1 year, T3-T2: 2 years). The cephalometric films were analysed according to the structural superimposition method of Bj&#xF6;rk. All tracings were double-digitized and the measurements were calculated by a computer program. Intragroup changes and intergroup differences were statistically analysed. Forward movement of the maxilla (P < 0.01), backward movement and rotation of the mandible, an increase in the ANB angle (P < 0.001), lower face height and overjet (P < 0.001), a decrease of overbite, and an improvement in the sagittal lip relationship (P < 0.01) presented significant intergroup differences between T2 and T1. During the second phase of treatment T3-T2, although not statistically significant, forward movement of the maxilla was less than in the control subjects. Overall changes during the observation period T3-T1 revealed that correction was mainly due to favourable changes in the mandibular and dentoalveolar components of the discrepancy, while these in maxillary position were not different from the control group. The soft tissue profile improved significantly (P < 0.001) in the treatment group. Comparison with the Class I controls at the end of the observation period confirmed that some Class III characteristics still remained in the treated patients.

PMID: 16731542 [PubMed - indexed for MEDLINE]


Free Full Text ArticleHerbst/multibracket appliance treatment of Class II division 1 malocclusions ...
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Herbst/multibracket appliance treatment of Class II division 1 malocclusions in early and late adulthood. a prospective cephalometric study of consecutively treated subjects.

Eur J Orthod. 2006 Aug;28(4):352-60

Authors: Ruf S, Pancherz H

A prospective study of 23 consecutive adult Class II division 1 malocclusion subjects (19 female and 4 male) treated with the Herbst/multibracket (MB) appliance is presented. The skeletal, dental, and facial profile changes were evaluated in addition to the mechanism of Class II correction during the Herbst phase and the settling of the occlusion during the MB phase. The mean pre-treatment age of the subjects was 21.9 years (15.7-44.4 years). Lateral head films in habitual occlusion from before treatment (T1) and after the Herbst (T2) and MB (T3) phases were analysed using standard cephalometrics and the sagittal occlusion analysis. For the standard cephalometrics, normal growth standards were utilized as control parameters. All patients were treated successfully to a Class I occlusal relationship with a normal overjet and overbite. The mandibular variables (SNB and SNPg) showed an angular increase (1.22 and 0.93 degrees, respectively) during T2-T1 followed by an angular reduction (0.40 and 0.23 degrees, respectively) during T3-T2. Compared with normal growth standards, all mandibular parameters were affected favourably by Herbst/MB treatment. Both the skeletal and soft tissue profile convexities were significantly reduced. Over the entire observation period (T3-T1), the largest amount of profile convexity reduction was seen for the soft tissue profile excluding the nose (mean 3.14 degrees). Class II correction was achieved by both skeletal and dental changes: overjet correction by 13 per cent skeletal and 87 per cent dental changes, and molar correction by 22 per cent skeletal and 78 per cent dental changes. In conclusion, on a short-term basis, the Herbst/MB appliance combination was found to be a powerful tool for non-surgical, non-extraction, treatment of Class II division I subjects in early and late adulthood.

PMID: 16644850 [PubMed - indexed for MEDLINE]


Free Full Text ArticleMorphometric analysis of mandibular growth in skeletal Class III malocclusion.
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Morphometric analysis of mandibular growth in skeletal Class III malocclusion.

J Formos Med Assoc. 2006 Apr;105(4):318-28

Authors: Chang JZ, Chen YJ, Chang FH, Yao JC, Liu PH, Chang CH, Lan WH

BACKGROUND: The craniofacial growth patterns of untreated individuals with skeletal Class III malocclusion have rarely been systemically investigated. This study used morphometric techniques to investigate the growth characteristics of the mandible in individuals with skeletal Class III malocclusion. METHODS: Lateral cephalometric head films of 294 individuals with untreated skeletal Class III malocclusion (134 males, 160 females) were selected and divided into five triennial age groups (T1-T5) and by gender to identify the morphologic characteristics and sexual dimorphism in changes of mandibular growth. Procrustes, thin-plate spline, and finite element analyses were performed for localization of differences in shape and size changes. Maximum and minimum principal axes were drawn to express the directions of shape changes. RESULTS: From T1 (age 6-8 years) to T4 (age 15-17 years), the distribution of localized size and shape changes of the mandible was very similar between the two genders. From T1 to T2 (age 9-11 years), significant lengthening of the condylar region was noted (23.4-39.7%). From T2 to T3 (age 12-14 years), the greatest size and shape change occurred at the condylar head (27.4-34.9%). From T3 to T4, the greatest size and shape changes occurred in the symphyseal region (23.6-42.1%). From T4 to T5 (age>or=18 years), significant sexual dimorphism was found in the distribution and amount of localized size and shape changes. Females displayed little growth increments during T4. Despite differences in the remodeling process, the whole mandibular configurations of both genders exhibited similarly significant upward and forward deformation from T4 to T5. CONCLUSION: We conclude that thin-plate spline analysis and the finite element morphometric method are efficient for the localization and quantification of size and shape changes that occur during mandibular growth. Plots of maximum and minimum principal directions can provide useful information about the trends of growth changes.

PMID: 16618612 [PubMed - indexed for MEDLINE]


Free Full Text ArticleInterceptive orthodontics: the need for early diagnosis and treatment of post...
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Interceptive orthodontics: the need for early diagnosis and treatment of posterior crossbites.

Med Oral Patol Oral Cir Bucal. 2006 Mar;11(2):E210-4

Authors: Casta&#xF1;er-Peiro A

Crossbites are the result of a malocclusion on the transverse plane of the maxilla and are defined as alterations of the correct alignment of the palatal cusps of the upper molars and premolars with the pits of the lower molars and premolars. Transverse alterations are frequently seen in general dental practices and it is necessary to establish a good differential diagnosis in order to adopt the treatment that will achieve the greatest efficiency and the most stable results possible. Skeletal constriction, dentoalveolar constriction and dental constriction must therefore be differentiated, as each requires different treatment with different orthodontic appliances. This article aims to provide a simple guide to the correct diagnosis of transverse anomalies and to choosing the most suitable orthodontic appliance for each case.

PMID: 16505804 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThin-plate spline analysis of the effects of face mask treatment in children ...
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Thin-plate spline analysis of the effects of face mask treatment in children with maxillary retrognathism.

J Formos Med Assoc. 2006 Feb;105(2):147-54

Authors: Chang JZ, Liu PH, Chen YJ, Yao JC, Chang HP, Chang CH, Chang FH

BACKGROUND: Face mask therapy is indicated for growing patients who suffer from maxillary retrognathia. Most previous studies used conventional cephalometric analysis to evaluate the effects of face mask treatment. Cephalometric analysis has been shown to be insufficient for complex craniofacial configurations. The purpose of this study was to investigate changes in the craniofacial structure of children with maxillary retrognathism following face mask treatment by means of thin-plate spline analysis. METHODS: Thirty children with skeletal Class III malocclusions who had been treated with face masks were compared with a group of 30 untreated gender-matched, age-matched, observation period-matched, and craniofacial configuration-matched subjects. Average geometries, scaled to an equivalent size, were generated by means of Procrustes analysis. Thin-plate spline analysis was then performed for localization of the shape changes. RESULTS: Face mask treatment induced a forward displacement of the maxilla, a counterclockwise rotation of the palatal plane, a horizontal compression of the anterior border of the symphysis and the condylar region, and a downward deformation of the menton. The cranial base exhibited a counterclockwise deformation as a whole. CONCLUSION: We conclude that thin-plate spline analysis is a valuable supplement to conventional cephalometric analysis.

PMID: 16477335 [PubMed - indexed for MEDLINE]


Free Full Text ArticleSagittal airway dimensions following maxillary protraction: a pilot study.
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Sagittal airway dimensions following maxillary protraction: a pilot study.

Eur J Orthod. 2006 Apr;28(2):184-9

Authors: Sayinsu K, Isik F, Arun T

The relationship between changes in the position of the maxillary structures caused by maxillary protraction therapy and airway dimensions have not been investigated as comprehensively as the accompanying skeletal changes. The purpose of this study was to examine the effects of rapid palatal expansion (RPE) used in conjunction with maxillary protraction headgear on the sagittal dimension of the airway. The treatment sample consisted of 19 Class III patients (12 girls, 7 boys) with a mean age of 10.51 +/- 1.15 years, presenting with maxillary retrognathism. A cap splint type rapid palatal expander that had hooks between the upper lateral and canine teeth was used intraorally, and a Petit type facemask device extraorally, for an average of 6.78 +/- 0.93 months. Pre- and post-treatment cephalometric radiographs were evaluated. The results of the study revealed that point A moved anteriorly. The palatal plane showed a counter-clockwise rotation matched by the clockwise rotation of the mandible and an accompanying decrease in SNB angle. The vertical parameters showed a statistically significant increase. The head was in a more extensive position in relation to the cervical vertebrae. The nasopharyngeal airway measurements (PNS-ad1, PNS-ad2) showed an increase of 2.71 +/- 3.35 and 3.03 +/- 2.37 mm, respectively. These results demonstrated that limited maxillary widening together with protraction of the maxilla, improve nasopharyngeal but not oropharyngeal airway dimensions in the short term.

PMID: 16464873 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEffects of a segmented removable appliance in molar distalization.
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Effects of a segmented removable appliance in molar distalization.

Eur J Orthod. 2006 Feb;28(1):65-73

Authors: Akin E, Gurton AU, Sagdic D

The aim of the present investigation was to evaluate the skeletal and dentoalveolar treatment effects of a segmented removable appliance [removable molar distalizer (RMD)] for molar distalization. The study was conducted on 28 patients (12 females and 16 males), with a mean age of 11.8 years. All presented with a skeletal Class I malocclusion and a bilateral dental Class II molar relationship. The pre- and post-distalization records included lateral head films, study models and standard photographs. The findings were evaluated with a paired samples t-test. The average maxillary first molar distalization with the RMD was 3.98 mm, with 4.61 degrees of distal tipping. The maxillary second premolars drifted distally 2.13 mm on average with 1.54 degrees of distal tipping, while the maxillary first premolars showed 1.23 mm of mesial movement and 1.98 degrees of mesial tipping. The incisors protruded 1.09 mm with 1.27 degrees of labial tipping. The RMD was effective in distal molar movement and all patients attained a bilateral Class I molar relationship in an average period of 4.5 months. Hygiene problems and mucosal irritations, frequently found with fixed intraoral distalization techniques, were not observed during the distalization period.

PMID: 16436365 [PubMed - indexed for MEDLINE]


Free Full Text ArticleA comparative study of cephalometric and arch width characteristics of Class ...
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A comparative study of cephalometric and arch width characteristics of Class II division 1 and division 2 malocclusions.

Eur J Orthod. 2006 Apr;28(2):179-83

Authors: Isik F, Nalbantgil D, Sayinsu K, Arun T

The aim of this compound cephalometric and arch-width study was to determine any dental and/or skeletal differences between subjects with Class II division 1 and Class II division 2 malocclusions. The dento-skeletal characteristics of Class II subjects were evaluated using lateral cephalometric radiographs and dental casts of 90 untreated patients. The sample included 46 Class II division 1 patients (19 girls and 27 boys) with a mean age of 15.27 +/- 2.48 years, and 44 Class II division 2 patients (27 girls and 17 boys) with a mean age of 15.95 +/- 3.25 years. The intermolar, interpremolar and intercanine measurements were carried out on study models. The radiographs were digitized and processed using Dolphin Imaging software. In addition to standard descriptive statistical calculations, an independent samples t-test was carried out in order to compare the two groups. The non-parametric Mann-Whitney U test was utilized for the parameters for the data which were not normally distributed. The only statistically significant difference between the groups for the study model measurements was mandibular intercanine width. The cephalometric results revealed that SNB angle was responsible for the skeletal sagittal difference between the two groups. In addition, the Class II division 1 group had higher vertical proportions and the Class II division 2 group a more concave profile with a prominent chin. The sagittal skeletal pattern of Class II division 2 subjects was found to be very similar to the Class I skeletal relationship, with no evidence of any mandibular restriction.

PMID: 16431898 [PubMed - indexed for MEDLINE]


Free Full Text ArticleA computerized photographic assessment of the relationship between skeletal d...
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A computerized photographic assessment of the relationship between skeletal discrepancy and mandibular outline asymmetry.

Eur J Orthod. 2006 Apr;28(2):97-102

Authors: Good S, Edler R, Wertheim D, Greenhill D

The aim of this study was to investigate the relationship between mandibular outline asymmetry and skeletal discrepancy in a sample of orthodontic patients (33 females, 33 males) aged from 8 to 19 years. Skeletal discrepancy was assessed in both the anteroposterior and vertical planes, using standard cephalometric analyses. All were photographed under standardized conditions and the photographs were then digitized for analysis using a computerized system to assess differences in four variables (area, perimeter, compactness and moment-ratio) between the right and left sides of the mandibular outline. The results showed good repeatability of the photographic, cephalometric and digitization methods. A statistically significant relationship was found between mandibular outline asymmetry and both anteroposterior and vertical skeletal discrepancy in this sample, when compared with patients with an average skeletal pattern. There appeared to be a statistically significant relationship between a reduced ANB angle (< 3 degrees) and mandibular outline asymmetry (P = 0.051), as well as between an increase in lower face height and mandibular asymmetry (P = 0.023).

PMID: 16431897 [PubMed - indexed for MEDLINE]


Free Full Text Article[A cephalometric study on Twin-block appliance for treatment of early skeleta...
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[A cephalometric study on Twin-block appliance for treatment of early skeletal Class II malocclusion]

Shanghai Kou Qiang Yi Xue. 2005 Dec;14(6):569-72

Authors: Liu Y, Liu YH

PURPOSE: To investigate the dentofacial morphological changes and the indication of Twin-block appliance for treatment of skeletal Class II malocclusion. METHODS: Twenty-one patients (5 degrees <ANB<10 degrees , 12 males,9 females) were recruited with an average age of 11.5 years.Lateral headfilm were performed for each patient before and after treatment with Twin-block appliance. Fifteen cephalometrics parameters were selected and measurement was performed. Paired t test and multiple regression analysis were used for statistical analysis. RESULTS: After treatment SNB(degrees), (L1-MP) (degrees), (Co-Go) (mm),(Go-Gn) (mm),(Co-Gn) (mm),(Sn-A'-UL) (degrees), (LL-B'-Pos) (degrees) increased significantly(P<0.05) ; ANB(degrees), WITS, OJ(mm), (U1-SN)(degrees), (UL-E line)(mm), (LL-E line)(mm) decreased significantly(P<0.05). ANB(<) and (U1-SN)(<) before treatment were significantly related to reduction in overjet (y=-37.14+0.43 ANB+0.36 (U1-SN), r(2)=0.62); SNA( degrees ) and SNB( degrees ) before treatment were significantly related to reduction in (UL-E line) (mm) (y=-5.37+0.44SNA-0.37SNB, r(2)=0.53); (U1-SN) (degrees) and (L1-MP)(degrees) before treatment were significantly related to reduction in( LL-E line) (mm) (y=-7.65+0.18 (U1-SN )-0.09 (L1-MP), r(2)=0.58). CONCLUSION: Twin-block appliance can be used successfully for early treatment of skeletal Class II malocclusion. It is more indicated for patients with retruded mandible , more labially inclined upper incisors and more upright lower incisors.

PMID: 16400480 [PubMed - in process]


Free Full Text Article[Temporomandibular joint involvement in juvenile idiopathic arthritis: treatm...
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[Temporomandibular joint involvement in juvenile idiopathic arthritis: treatment with an orthodontic appliance]

Reumatismo. 2005 Jul-Sep;57(3):201-7

Authors: Bellintani C, Ghiringhelli P, Gerloni V, Gattinara M, Farronato G, Fantini F

OBJECTIVE: About 65% of children suffering from juvenile idiopathic arthritis (JIA) shows a more or less marked involvement of temporo-mandibular joint (TMJ) with altered mandibular growth, resorption of the condyles, occlusary instability, reduced chewing ability and facial dysmorphia. The purpose of our study is to prevent and to treat the progressive evolution of JIA on craniofacial growth and morphology with a functional appliance; surgery should be considered only in so far as the adequacy of TMJ movement is concerned. METHODS: From 1992 until now 72 children with proved JIA and TMJ involvement have been treated (50 females, 22 males, aged 6 to 16 years old). TMJ involvement was bilateral in 61% and unilateral in 39% of patients. A diagnostic workup was carried out involving tomograms of TMJ and cephalometric radiograph and analysis. The authors used a bimaxillary activator in the attempt to modify the unfavourable growth pattern and provide a gradual ante-rotation of the jaw. RESULTS: Almost all JIA patients showed satisfactory long term results, easing of pain, reduced skeletal discrepancy, increased function and good facial profile. CONCLUSIONS: The long term results of this study indicate that orthopaedic therapy might control the vicious circle of the malocclusion in children with JIA, preventing exacerbation of mandibular clockwise rotation. Surgical intervention for the improvement of TMJ function should be considered only if a severe restricted state is imminent.

PMID: 16258606 [PubMed - indexed for MEDLINE]


Free Full Text ArticleCephalometric standards for Slovenians in the mixed dentition period.
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Cephalometric standards for Slovenians in the mixed dentition period.

Eur J Orthod. 2006 Feb;28(1):51-7

Authors: Drevensek M, Farcnik F, Vidmar G

The aim of this study was to develop standard cephalometric values for Slovenians in the period of the mixed dentition. Eighty-eight children were included in the study (46 girls and 42 boys, mean age 9.31 +/- 1.52 years). The selection criteria were: in the mixed dentition, a score of the modified Eismann method for an objective assessment of malocclusion of less than 15 points, the absence of aplasia and supernumerary teeth, no congential anomalies and no previous orthodontic treatment. Twenty-five cephalometric measurements were performed twice to analyse the size and shape of the craniofacial complex. The reliability of the measurements was assessed by correlation coefficients, regression, and analysis of inter-subject differences; satisfactory results were obtained. The differences between boys and girls and between those in the early and late mixed dentition period were tested with a two-way analysis of variance. The most pronounced changes between the early and late mixed dentition were observed in the vertical skeletal relationships: a decrease in mandibular inclination, interbasal angle and gonial angle, and an increase in anterior and posterior face height. Sagittal skeletal relationships remained constant from the early to the late mixed dentition. No significant differences were found between the observed developmental stages. Significant differences between genders were found only for anterior and posterior face height, with boys showing larger values (P </= 0.001). As there were no significant differences between the early and late mixed dentition, the mean measurement values of the total sample can be used as cephalometric standards for Slovenians in the mixed dentition period.

PMID: 16230328 [PubMed - indexed for MEDLINE]


Free Full Text Article[Treatment of Angle Class II division I malocclusion cases with Twin-block ap...
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[Treatment of Angle Class II division I malocclusion cases with Twin-block appliance combined with face bow and intermaxillary elastic: report of 17 cases]

Shanghai Kou Qiang Yi Xue. 2005 Aug;14(4):365-9

Authors: Gong X, Qian YF

PURPOSE: The aim of this study was to evaluate the clinical value of the Twin-block appliance combined with face bow and intermaxillary elastic on Class II division I malocclusion in 17 cases. METHODS:17 cases with skeletal Class II(I) malocclusion were included, all cases were treated with Twin-block appliance combined with face bow and intermaxillary elastic. The methods of bite construction, fabrication of the application were introduced. Lateral cephalometric films were taken before and after treatment. Cephalometric analysis was conducted to evaluate the treatment effects. Student's t test was used to determine the effect on jaw growth before and after treatment. RESULTS: The treatment resulted in good outcomes: the neutral or mesial relations of the permanent first molars were reached, the deep overjet was reduced. The S-N-ss angle and the length of maxilla (ss/ref pl) were reduced (P<0.05, P<0.01). The pg/ref pl, co/ref pl+pg/ref pl and the S-N-sm angle had a significant increase (P<0.001). The convexity angle and s-N-sm angle had a significant change (P<0.001).The FMA angle had no change (P>0.05). CONCLUSION: The Twin-block appliance combined with face bow and intermaxillary elastic was very effective on improving mandible growth and inhibiting maxilla growth, the sagittal relationship between the upper and lower jaws was more compatible, the profile was improved.

PMID: 16155699 [PubMed - in process]


Free Full Text ArticlePrediction of post-treatment outcome after combined treatment with maxillary ...
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Prediction of post-treatment outcome after combined treatment with maxillary protraction and chincap appliances.

Eur J Orthod. 2006 Feb;28(1):89-96

Authors: Yoshida I, Yamaguchi N, Mizoguchi I

The aims of this study were to identify differences in the initial skeletal morphology between successful and unsuccessful groups and to establish a novel method for predicting the final outcome of treatment with a maxillary protraction appliance (MPA) and chincap. The cephalograms used in this study were taken from 32 Japanese girls (mean age 10.2 years) with a Class III malocclusion at the beginning of treatment with an MPA and chincap (T1), at removal of the appliance (T2), and during the final post-treatment period (T3). The subjects were divided into two groups according to the treatment outcome at T3. Lower face height (ANS-Me), total face height (N-Me), ratio of face height (ANS-Me/N-ANS), maxillary position, mandibular plane and gonial angle at T1 were all significantly larger in the unsuccessful group, compared with the successful group. Discriminant analysis indicated that lower face height and gonial angle were significant determinants for distinguishing between the two groups at T1. From T1 to T2, while the anterior displacement of the maxilla was almost the same in the two groups, SNB decreased by 1.6 degrees in the successful group and 0.4 degrees in the unsuccessful group. After orthopaedic treatment, a second phase of treatment with a multibracket system was performed (T2 to T3). From T2 to T3, SNA increased by 0.4 degrees in the successful group and decreased by 0.7 degrees in the unsuccessful group. These results indicate that the vertical dimensions of the craniofacial skeleton are important for predicting the prognosis of skeletal Class III patients treated with a MPA and chincap and that the discriminant formula established in this study is effective in predicting the final treatment outcome.

PMID: 16113036 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEffects of activator and activator headgear treatment: comparison with untrea...
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Effects of activator and activator headgear treatment: comparison with untreated Class II subjects.

Eur J Orthod. 2006 Feb;28(1):27-34

Authors: T&#xFC;rkkahraman H, Sayin MO

The aims of this study were to determine whether the activator and activator headgear encourage mandibular growth, and whether there is any superiority of one appliance over the other or if the resultant changes are due to normal growth. Forty-nine skeletal Class II division 1 patients were selected. Thirty-three (13 females, 20 males; mean age 12.52 +/- 1.42 years) were treated with an Andresen activator and the remaining 16 (7 females, 9 males; mean age 13.04 +/- 1.47 years) with an activator headgear combination. Twenty Class II subjects (9 females, 11 males; mean age 12.57 +/- 1.11 years) who had previously refused treatment served as a control group. Cephalometric landmarks were marked and digitized by one author to avoid inter-observer variability. Nine angular and 12 linear measurements were established and measured using Vistadent AT software. A paired-sample t-test and an ANOVA test were used to statistically evaluate the findings. The results revealed that both the activator and the activator headgear combination significantly (P < 0.001) encouraged mandibular growth, but had little restraining effect on the maxilla. The mandibular incisors were more controlled in the activator headgear combination group. The resultant skeletal, dentoalveolar and soft tissue changes differed significantly from those due to growth.

PMID: 16093256 [PubMed - indexed for MEDLINE]


Free Full Text ArticleComparative cephalometric study of Class III malocclusion in Saudi and Japane...
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Comparative cephalometric study of Class III malocclusion in Saudi and Japanese adult females.

J Oral Sci. 2005 Jun;47(2):83-90

Authors: Bukhary MT

The cephalometric features of class III malocclusion in Saudi adult females were investigated and compared with reference data for Japanese females. The sample consisted of 30 standardized pre-treatment cephalometric radiographs of adult Saudi females diagnosed as having skeletal class III malocclusion. The radiographs were traced and digitized. Linear and angular variables were obtained for comparison of cranial base, maxilla, mandible, intermaxillary and dentoalveolar measurements. The method error in identifying and locating the anatomical landmarks was small and acceptable. Student's t-test was used for comparing the measurements. The results showed that Saudi females had a larger anterior cranial base, a smaller posterior cranial base, a smaller cranial base angle, smaller anterior and posterior facial heights, downward tipping of the maxilla, a retruded chin, a less steep mandibular plane, an increased joint angle, a smaller ramus, body and total mandibular length, and less retroclined mandibular incisors. The null hypothesis of no difference between the two groups was rejected. These results appear to suggest real differences in skeletal features between Saudi and Japanese adult females.

PMID: 16050488 [PubMed - indexed for MEDLINE]


Free Full Text ArticleEffects of camouflage treatment on dentofacial structures in Class II divisio...
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Effects of camouflage treatment on dentofacial structures in Class II division 1 mandibular retrognathic patients.

Eur J Orthod. 2005 Oct;27(5):524-31

Authors: Demir A, Uysal T, Sari Z, Basciftci FA

The aims of this study were to determine the changes in the dentofacial structures of Class II division 1 mandibular retrognathic patients treated with bilateral extraction of the upper first premolars, and to compare pre- and post-treatment values with the cephalometric norms of Anatolian Turkish adults. The Class II division 1 subjects included 20 males and 33 females (mean age: 17.08 +/- 1.03 years). All received comprehensive orthodontic treatment using an edgewise appliance and appropriate headgear. Lateral cephalograms were taken at the beginning and end of treatment. Twenty-five (14 linear and 11 angular) measurements were analysed on each radiograph. Each cephalogram was traced and digitized. For statistical evaluation, paired and independent-samples t-tests were performed. When the pre- and post-treatment measurements were compared, statistically significant differences were found for nine of 25 measurements. During treatment the facial axis, U1-SN ( degrees ), U1-NA (mm), U1-NA ( degrees ), H angle and upper lip to E plane measurements decreased, while N-ANS, interincisal angle and upper lip to Steiner S line increased. No statistically significant gender differences were found. Significant improvements were determined in ANS-Me and L1-APo measurements compared with Turkish norms. However, statistically significant deterioration was found in values related to point A, upper incisor and lower lip measurements. The findings demonstrates that camouflage treatment in Class II, mandibular retrognathic subjects has characteristic skeletal, dental and soft tissue effects on the dentofacial complex.

PMID: 16049038 [PubMed - indexed for MEDLINE]


Free Full Text ArticleLong-term skeletal effects of mandibular symphyseal distraction osteogenesis....
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Long-term skeletal effects of mandibular symphyseal distraction osteogenesis. An implant study.

Eur J Orthod. 2005 Oct;27(5):512-7

Authors: Iseri H, Malko&#xE7; S

The purpose of this study was to investigate the long-term skeletal effects of mandibular symphyseal distraction osteogenesis (MSDO) with a tooth- and bone-borne distraction device, analysed using the metallic implant method. The study sample comprised 20 patients between 15.8 and 25 years of age, with a mean age of 20.01 +/- 2.25 years at the start of treatment. In 12 subjects, titanium implants were inserted in the mandible to analyse mandibular skeletal changes in the short and long term. A custom-made intraoral, tooth- and bone-borne distractor was designed and used. After a latency period of 7 days, the distractor was activated twice daily, by a total amount of 1 mm. Postero-anterior (PA) cephalograms were obtained at the start of distraction and at the end of consolidation (94.95 +/- 5.79 days after surgery) and follow-up periods (21.5 +/- 4.6 months after consolidation). The data were analysed statistically using paired t-tests. The mean amount of screw activation was 8.10 +/- 1.68 mm. The inter-symphyseal and inter-molar implant distances and the bimolar width significantly increased during the consolidation period (P < 0.001) and were maintained at the end of the follow-up. On the other hand, the bicondylar width was markedly decreased (P < 0.05), while no significant skeletal changes were observed in bigonion and biantigonion widths, inter-ramal implant distance, or inter-ramal and implant angles at the end of the consolidation period. The long-term findings of this study indicate that MSDO provides an efficient and stable non-extraction treatment alternative, mainly by increasing the anterior mandibular skeletal and dental arches.

PMID: 16043467 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThe relationship between temporomandibular joint disc morphology and stress a...
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The relationship between temporomandibular joint disc morphology and stress angulation in skeletal Class III patients.

Eur J Orthod. 2005 Oct;27(5):501-6

Authors: Ueki K, Nakagawa K, Marukawa K, Takatsuka S, Yamamoto E

The aim of this study was to examine the relationship between disc position and stress direction on the condyle by means of stress analysis using the rigid body spring model (RBSM) theory. The material consisted of 88 joints of 44 Class III dentofacial deformity patients, divided into symmetry and asymmetry groups on the basis of the Mx-Md midline position. The asymmetry group was identified by comparison with a reference midline vertical plane passing through a plane from ANS to Me. Asymmetry was diagnosed when the angle between these two planes was greater than 3 degrees. The geometry of the stress analysis model was based on sagittal tomography of the subject. The first molar, gonial angle, and the most anterior, superior, and posterior points on the condyle were plotted on a computer display, and stress angulation on the condyles was calculated with the RBSM program. In addition to anterior displacement with or without reduction, three types of disc position could be identified using magnetic resonance imaging (MRI): anterior, fully covered and posterior. In the asymmetric group, stress angulation was significantly higher (P < 0.05) at the deviation side compared with the non-deviation side. There was also a significant correlation between disc position and stress angulation (P < 0.05). In the asymmetry group, regression analysis indicated a significant correlation (P < 0.001) between the difference in stress angulation (between the deviation side and the non-deviation side) and the degree of asymmetry (measured by the angle of asymmetry). This study demonstrated that temporomandibular joint (TMJ) stress was associated with TMJ morphology in Class III patients whether or not they were asymmetric.

PMID: 16024561 [PubMed - indexed for MEDLINE]


Free Full Text ArticleCephalometric evaluation of class-III patients with chin cap and tongue guard.
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Cephalometric evaluation of class-III patients with chin cap and tongue guard.

J Indian Soc Pedod Prev Dent. 2005 Jun;23(2):63-6

Authors: Danaie SM, Salehi P

The purpose of this study was to determine the effect of chin cap therapy combined with an upper tongue guard in the early treatment of class-III malocclusion on the nasomaxillary complex and mandible. The subjects of this study consisted of 40 patients aged 5-13 years (mean age of 8.5 +/- 2). All of them possessed an anterior cross bite and/or concave profile. The mean force of chin cap was determined to be 200 g on each side for 18 h/day and the mean treatment period was 22 months. The cephalometric analyses including skeletal, dental, and soft tissue analysis were carried out before and after treatment. The analysis of the cephalometric measurements revealed a negative correlation between the combination effects of chin cap therapy upper tongue guard. This effect appeared in the early stages of treatment. It was a case-control study and Wilcoxon test was used for statistical analysis. The comparison of dependent variables revealed that skeletal effects of chin cap therapy were more than dental and soft tissue effects. Changes in the upper and lower pharyngeal spaces were not significant. A reduction of nasolabial angle occurred due to the protrusion of upper incisors. Finally, it was shown that the combination of chin cap and upper tongue guard could be more effective in the early treatment.

PMID: 16012206 [PubMed - in process]


Free Full Text Article[A study on the extraoral cervical traction in the treatment of skeletal Clas...
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[A study on the extraoral cervical traction in the treatment of skeletal Class II division 1 malocclusion in mixed dentition]

Shanghai Kou Qiang Yi Xue. 2005 Jun;14(3):243-6

Authors: Sun Y, Liu HH, Cao HJ

PURPOSE: To evaluate the effects of extraoral cervical traction on skeletal Class II division 1 malocclusion of early or late mixed dentition and discuss the optimal treatment timing. METHODS: The sample consisted of two groups of skeletal Class II division 1 malocclusion. One group with 11 cases was treated started in early mixed dentition while the other with 15 cases in late mixed dentition. All cases were treated with extraoral cervical traction headgear. Cephalometric analysis was conducted to evaluate the treatment effects. Student's t test was applied for statistical analysis. RESULTS: SNA, ANB and the length of maxilla (A-Ptm) were reduced and the inclination of maxillary incisor was decreased in both two groups. When comparing the two groups, it was found that the reduction of SNA was more notable, which means the inhibition of the maxilla was more evident in late mixed dentition. The difference was statistically significant (P<0.01). There was no significant difference on the distalization of the first upper molar between two groups (P<0.01). CONCLUSIONS: The extraoral cervical traction might be more effective in late mixed dentition to restrain maxillary growth in the treatment of skeletal Class II division 1 malocclusion.

PMID: 15995768 [PubMed - in process]


Free Full Text ArticleThree-part bi-maxillary osteotomy: a case report involving resorbable plates.
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Three-part bi-maxillary osteotomy: a case report involving resorbable plates.

J Orthod. 2005 Jun;32(2):75-84

Authors: Waring D, Harrison J, Boyle M

This case report describes a patient who presented with a severe class 2 skeletal discrepancy together with a Class II malocclusion and a large anterior open bite. The malocclusion and skeletal discrepancy were managed with a combination of orthodontic and orthognathic treatment. The orthognathic surgery was undertaken following orthodontic decompensation using sectional mechanics to allow a segmental bimaxillary osteotomy and genioplasty to be performed. Although the discrepancy was severe using this combination of treatment, a successful outcome, both facially and occlusally, was achieved.

PMID: 15994980 [PubMed - indexed for MEDLINE]


Free Full Text ArticlePerceptions of facial aesthetics in two and three dimensions.
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Perceptions of facial aesthetics in two and three dimensions.

Eur J Orthod. 2005 Aug;27(4):363-9

Authors: Todd SA, Hammond P, Hutton T, Cochrane S, Cunningham S

The aims of this study were to investigate whether the preferred facial relationship chosen by professionals and the general public is Class I and to ascertain whether viewing two-dimensional (2D) or three-dimensional (3D) images had any effect on the ranking of facial attractiveness. Orthodontists (n = 47), maxillofacial surgeons (n = 25) and members of the general public (n = 78) assessed 2D and 3D facial scans of two males and two females that had been morphed to produce five images reflecting different skeletal patterns: Class I, mild and moderate Class II, and mild and moderate Class III. Each assessor placed the images in rank order of preference, after viewing alternate 2D and 3D image formats for each face. The data were analysed using logistic regression.In 2D, professionals (orthodontists and maxillofacial surgeons) chose Class I as the preferred facial image more frequently than the general public for only one of the four faces. However, in 3D format they chose Class I as the preferred facial image for some subject faces more, and others less, frequently when compared with the general public. The gender of the assessor was not significant when assessing the preferred facial relationship for Class I images in either 2D or 3D formats. The oldest assessors (56+ years) were significantly less likely than the younger age groups to select Class I as the preferred facial relationship in both 2D and 3D. In summary, there was too great a degree of variation to say that a difference between 2D and 3D facial images was evident.

PMID: 15961568 [PubMed - indexed for MEDLINE]


Free Full Text ArticleThe effects of the Twin-block appliance treatment on the skeletal and dentola...
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The effects of the Twin-block appliance treatment on the skeletal and dentolaveolar changes in Class II Division 1 malocclusion.

Medicina (Kaunas). 2005;41(5):392-400

Authors: Sidlauskas A

Class II Division 1 malocclusion is the most frequent problem in the orthodontic practice. During the last ten years treatment with Twin-block functional appliance has gained popularity. The aim of the present study was to analyze the skeletal and dentoalveolar changes in Class II Division 1 malocclusions cases treated with Twin-block appliance. MATERIAL AND METHODS: Cephalometric analysis of skeletal and dentoalveolar facial structures of 34 Class II Division 1 patients treated with Twin-block appliance was performed using the same reference system before and after treatment. Longitudinal growth records of persons with excellent occlusion-Bolton standards have been used for the control in order to assess natural growth. RESULTS: Mandibular length as measured from point Articulare to point Pogonion increased by 4.6 mm in the Twin-block group compare with 2.2 mm in the control Bolton standards group. Skeletal and dentoalveolar relationship between maxillary and mandibular bases improved significantly: ANB angle reduced by 2.3 degrees, overjet reduction was 4.7 mm, postnormal molar position corrected by 3.6 mm. CONCLUSIONS: Twin-block appliance statistically significantly increases mandibular length by 2.4 mm during 12-month treatment period. With the Twin-block treatment about 40% overjet correction was achieved by skeletal and about 60% by dentoalveolar changes. Correction of postnormal buccal segments in Twin-block group was achieved by the combination of distal movement of the upper molars (0.7 mm dentoalveolar, 0.3 mm skeletal) and forward migration of lower molars (0.9 mm dentoalveolar and 1.7 mm skeletal).

PMID: 15947523 [PubMed - indexed for MEDLINE]


Free Full Text Article[Effect of Twin-block appliance in the treatment of Class II and division I m...
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[Effect of Twin-block appliance in the treatment of Class II and division I malocclusion: a cephalometric study in 12 patients]

Shanghai Kou Qiang Yi Xue. 2005 Feb;14(1):90-3

Authors: Luo Y, Fang G

PURPOSE: To quantitatively evaluate the skeletal and dentoalveolar changes induced by Twin-block appliance for treatment of Class II,division I malocclusions in growing children. METHODS: Twelve patients with Class II, division I malocclusions aged 10 to 12 years were investigated. The records were evaluated and compared with an age-matched sample of untreated Class II control subjects. The follow-up period was 12 months. Group t test was used for comparison. RESULTS: In the treatment group, the upper incisors retroclination of the upper incisors and the mandibular forward movement contributed more to the overjet reduction. The skeletal and dental effects changes molar correction were almost similar. The mandibular growth in the treatment group was 2.29 mm, greater than that in the control group. The posterior facial height and the anterior lower facial height increased by 2.28 mm and 2.58 mm respectively. On the other hand, unfavorable vertical changes were not observed. CONCLUSIONS: The treatment of Class II division I malocclusion with Twin-block appliance was effective in reducing overjet, correcting molar relationship and improving soft tissue profile. It can also enhance mandibular growth.

PMID: 15747025 [PubMed - in process]


Free Full Text ArticleMorphology of Singapore chinese.
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Morphology of Singapore chinese.

Eur J Orthod. 2004 Dec;26(6):605-12

Authors: Yeong P, Huggare J

The aims of this study were to provide a description of the craniofacial morphology of Singaporean Chinese children and to compare gender differences.Lateral cephalometric radiographs were obtained of 81 Singaporean Chinese children (31 boys and 50 girls; mean age 12.7 and 12.5 years, respectively, standard deviation = 0.7) with Class I incisor relationships. The radiographs were traced and 27 hard and soft tissue cephalometric landmarks digitized. Fourteen linear and 13 angular cephalometric variables were obtained using the Neodigiplottrade mark computerized cephalometric analysis software. A comparison of the genders showed that girls had greater maxillary and mandibular protrusion, but the upper and lower incisor inclinations were reduced. In addition, girls showed reduced facial convexity and reduced upper lip prominence. Pogonion to nasion perpendicular was greater for boys. Although not statistically significant, the values of intermaxillary protrusion and Wits showed a tendency for the girls towards a Class III skeletal base. The boys also had statistically significantly longer cranial base lengths, and anterior and posterior face heights. Overall, the results reflect gender differences in both angular and linear cephalometric craniofacial measurements, which should be taken into account when establishing cephalometric reference data for Singaporean Chinese children.

PMID: 15650070 [PubMed - indexed for MEDLINE]


Free Full Text ArticleA case of Antley-Bixler syndrome with severe skeletal Cl. III malocclusion.
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A case of Antley-Bixler syndrome with severe skeletal Cl. III malocclusion.

Bull Tokyo Dent Coll. 2004 May;45(2):87-93

Authors: Tsuchiya Y, Sueishi K, Yatabe K, Yamaguchi H

Antley-Bixler syndrome is a disorder characterized by craniosynostosis, midface hypoplasia, choana blockade, and radiohumeral synostosis. However, the features of occlusion remain unclear. In this paper, we report a case of Antley-Bixler syndrome, a 7-year-old boy, from the viewpoint of orthodontics. From lateral cephalometric head film analysis, remarkable retardation of the anterior subcranial base, infraorbitale, and maxilla were notable, as was vertical growth restriction of the maxilla. The choana blockade tendency was also recognized. Moreover, although reverse occlusion was present, a mandibular retrognathic tendency was also present, and a short ramus mandible, remarkable mandibular vertical growth pattern, and skeletal open bite were present. In the dentition, two of the lower incisors were missing, and the present lower incisors were large. Maxillary and mandibular first molars were delayed in eruption. For treatment, the solutions to such remarkable skeletal problems were limited by the insufficiency of recovery of cranial formation after the operation. We planned a non-surgical treatment to expand the maxilla. It will be necessary to continually consider the treatment of his malocclusion as he continues to grow.

PMID: 15536859 [PubMed - indexed for MEDLINE]



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