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: Marşan 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]

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, Hägg 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]

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, N&#xE4;gerl 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]

A systematic review of cephalometric facial soft tissue changes with the Activator and Bionator appliances in Class II division 1 subjects.

Eur J Orthod. 2006 Dec;28(6):586-93

Authors: Flores-Mir C, Major PW

The objective of the present systematic review was to evaluate, through lateral cephalograms, facial soft tissue changes after the use of the Activator and Bionator appliances in Class II division 1 malocclusion subjects. Several electronic databases (PubMed, Medline, Medline In-Process and Other Non-Indexed Citations, Cochrane Database, Embase, Web of Sciences, and Lilacs) were searched with the assistance of a senior health sciences librarian. Abstracts, which appeared to fulfil the initial criteria, were selected by consensus. The original articles were then retrieved. Their references were also hand searched for possible missing articles. Clinical trials, which assessed facial soft tissue changes with the use of either an Activator or a Bionator appliance without any surgical intervention or syndromic characteristics, were considered. A comparable untreated control group was required to factor out normal growth changes. Five articles using the Activator and six using the Bionator fulfilled the selection criteria and quantified facial soft tissue changes. An individual analysis of these articles was undertaken and some methodological flaws were identified. Based on the available evidence, a significant amount of controversy regarding the soft tissue changes produced by the Activator and the Bionator exists. Soft tissue changes that were reported as being statistically significant were of questionable clinical significance. Long-term, double-blinded, prospective randomized clinical trials are needed to confirm the findings. Three-dimensional quantification is also required to overcome current limitations in our understanding of the soft tissue changes obtained with the use of removable functional appliances.

PMID: 17095741 [PubMed - indexed for MEDLINE]

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]

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]

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]

Expression of type X collagen and capillary endothelium in condylar cartilage during osteogenic transition--a comparison between adaptive remodelling and natural growth.

Eur J Orthod. 2006 Jun;28(3):210-6

Authors: Shen G, Zhao Z, Kaluarachchi K, Bakr Rabie A

Adaptive remodelling of the condylar cartilage in response to mandibular protrusion constitutes the rationale for bite-jumping appliances to solicit growth modification. By investigating the expression of type X collagen and capillary endothelium, this study was designed to evaluate the osteogenic transition of chondrogenesis during adaptive remodelling of condylar cartilage and compare it with that under natural condylar growth. One hundred female Sprague-Dawley rats, 35 days of age, were divided into five experimental groups (n = 15, fitted with bite-jumping appliances) where condylar adaptation was created by forward repositioning of the mandible, and five control groups (n = 5) where the condyles underwent natural growth. The animals were sacrificed at 3, 7, 14, 21 and 30 days and 7 mum serial sections of the condyles were processed for in situ hybridization and immunohistochemical analyses. The expression of type X collagen in the hypertrophic zone and capillary endothelium in the erosive zone of condylar cartilage were examined to evaluate osteogenic transition, a critical programme leading to endochondral ossification. The results showed that (1) The temporal pattern of the expression of type X collagen and capillary endothelium during condylar adaptation coincided with that during natural condylar growth. (2) The amount of the expression of these two factors during condylar adaptation was significantly higher than that during natural growth (P < 0.001). It is suggested that condylar adaptation in growing rats triggered by mandibular forward positioning enhances osteogenic transition which eventually results in increased bone formation.

PMID: 16679327 [PubMed - indexed for MEDLINE]

Oral applicances for obstructive sleep apnea?

Am Fam Physician. 2006 Mar 1;73(5):801-3

Authors: Cook V, Schooff M

PMID: 16529085 [PubMed - indexed for MEDLINE]

Twin-block re-activation.

J Orthod. 2006 Mar;33(1):3-6

Authors: Brennan JA, Littlewood SJ

This paper briefly reviews reasons for re-activating Twin-blocks, discussing different approaches and describing a new, simple, cost effective approach, which can be undertaken at the chairside.

PMID: 16514128 [PubMed - indexed for MEDLINE]

The treatment effects of Invisalign orthodontic aligners: a systematic review.

J Am Dent Assoc. 2005 Dec;136(12):1724-9

Authors: Lagrav&#xE8;re MO, Flores-Mir C

BACKGROUND: The authors conducted a systematic review of the literature to determine the treatment effects of the Invisalign orthodontic system (Align Technology), Santa Clara, Calif.). TYPES OF STUDIES REVIEWED: The authors reviewed clinical trials that assessed Invisalign's treatment effects in nongrowing patients. They did not consider trials involving surgical or other simultaneous fixed or removable orthodontic treatment interventions. RESULTS: The authors searched electronic databases (PubMed, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, Evidence Based Medicine Reviews, EMBASE Excerpta Medica, Thomsen's ISI Web of Science and LILACS) with the help of a senior health sciences librarian. They used "Invisalign" as the sole search term, and 22 documents appeared in the combined search. Thereafter, they used "clinical trials," "humans" and "Invisalign treatment effects" as abstract selection criteria. Only two published articles met these inclusion criteria, though after reading the actual articles, the authors determined that they did not adequately evaluate Invisalign treatment effects. Both articles identified methodological issues. CLINICAL IMPLICATIONS: The inadequately designed studies the authors found represented only a lower level of evidence (level II). Therefore, the authors found that no strong conclusions could be made regarding the treatment effects of Invisalign appliances. Future prospective randomized clinical trials are required to support, with sound scientific evidence, the claims about Invisalign's treatment effects. Clinicians will have to rely on their Invisalign clinical experience, the opinions of experts and the limited published evidence when using Invisalign appliances.

PMID: 16383056 [PubMed - indexed for MEDLINE]

Localized sequential use of resilient lining to generate orthodontic force in thermoformed active removable appliances.

J Orthod. 2005 Dec;32(4):235-40

Authors: Ng EW

A new modality of orthodontic treatment based on the thermoformed appliance was developed and trialled clinically. A light-cured resilient lining material commonly used for denture relining was placed locally and sequentially in thermoformed appliances to generate orthodontic forces. The new method appeared to be effective. All the presented cases showed substantial improvement in dental alignment. A number of orthodontic movements were demonstrated. Localized use of resilient lining in thermoformed orthodontic appliances appeared to be a promising alternative to other thermoformed active removable appliance (TARA) treatments. Further studies are required to optimize the procedures and explore its full potential.

PMID: 16333043 [PubMed - indexed for MEDLINE]

Soft tissue facial profile changes following functional appliance therapy.

Eur J Orthod. 2006 Feb;28(1):35-41

Authors: Quintão C, Helena I, Brunharo VP, Menezes RC, Almeida MA

The aim of this study was to evaluate changes in the facial profile resulting from the use of a twin block (TB) functional appliance. The sample comprised 38 patients (24 males and 14 females) with a Class II division 1 malocclusion. Nineteen subjects were treated with a functional appliance while the remaining 19, who did not undergo any intervention, served as the control. The mean age of the treated group was 9.5 years (SD 10 months) and of the control group 9.9 years (SD 13 months). Lateral cephalograms were obtained for all subjects at the initial consultation and again after one year. The changes in facial profile, resulting from treatment with the TB, were analysed after the influence of growth had been taken into account. The results showed a significant improvement in the facial profile, which closely followed the underlying dentoskeletal changes. Thus, the most significant effects were a total facial profile improvement, retraction of the upper lip and anterior movement of soft tissue pogonion (P < 0.05). Subjects treated with a TB appliance achieved improved facial harmony, but such changes were not observed in the control group.

PMID: 16113035 [PubMed - indexed for MEDLINE]

Effects of activator and activator headgear treatment: comparison with untreated Class II subjects.

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

Authors: Türkkahraman 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]

Sleep nasendoscopy: a diagnostic tool for predicting treatment success with mandibular advancement splints in obstructive sleep apnoea.

Eur J Orthod. 2005 Dec;27(6):607-14

Authors: Johal A, Battagel JM, Kotecha BT

This prospective, cohort study evaluated the role of sleep nasendoscopy (SNE) with simultaneous mandibular protrusion in predicting successful mandibular advancement splint (MAS) therapy in subjects with obstructive sleep apnoea (OSA). Nineteen OSA subjects diagnosed by overnight polysomnography were referred for MAS therapy, following SNE investigation. A Herbst MAS was fabricated for each subject. Once this had been adjusted for maximal, subjective, therapeutic effect, follow-up sleep studies were undertaken with the appliance in situ. The SNE was repeated with the appliance in place to allow the effects of the original mandibular protrusion and the actual effect of the MAS to be compared. The MAS was removed and the original and current site(s) of obstruction evaluated. Pre-treatment SNE showed airway obstruction at the following levels: intermittent multi-level (16 subjects), sustained multi-level (two subjects) and tongue base (one subject). In all individuals, gentle advancement of the mandible during SNE improved airway patency and reduced snoring. When the SNE was repeated with the MAS in situ, all subjects showed improvements in snoring and airway patency. Follow-up sleep studies confirmed the efficacy of the MAS, with all patients showing a reduction in the apnoea/hypopnoea index (AHI). Median reductions in AHI (from 28.1 to 6.1, P < 0.001) and Epworth Sleepiness Scale (ESS) scores (from 9 to 6, P < 0.001) were highly statistically significant. The results suggest that SNE with concomitant mandibular advancement to mimic MAS wear, could be a valuable prognostic indicator of successful MAS treatment.

PMID: 16049036 [PubMed - indexed for MEDLINE]

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]

Mandibular incisal edge demineralization and caries associated with Twin Block appliance design.

J Orthod. 2005 Mar;32(1):3-10

Authors: Dixon M, Jones Y, Mackie IE, Derwent SK

Demineralization and caries are well documented and unwanted complications of orthodontic therapy. These are most commonly reported in relation to fixed appliance therapy. Five cases are presented of patients undergoing Twin Block appliance therapy with the appliances incorporating lower labial segment capping, illustrating a pattern of demineralization and caries of the incisal tips of the mandibular labial segment, influenced by the incisal capping and the frequent intake of carbonated soft drinks.

PMID: 15784936 [PubMed - indexed for MEDLINE]

A comparison of the Twin Block and Herbst mandibular advancement splints in the treatment of patients with obstructive sleep apnoea: a prospective study.

Eur J Orthod. 2005 Feb;27(1):82-90

Authors: Lawton HM, Battagel JM, Kotecha B

This prospective, randomized, crossover study of 16 patients with obstructive sleep apnoea (OSA) [12 males, four females; median body mass index (BMI) 29.2 kg/m(2) (range 23.8-51.1); median age 44.8 years (range 24.0-68.4)] analysed the efficacy of the Twin Block (TB) in relation to the Herbst appliance as a mandibular advancement splint (MAS). Each subject was fitted with a TB and Herbst MAS in a random order with a washout period of 2 weeks between appliances. Once each patient was subjectively happy with the performance of each appliance, questionnaires and a visual analogue scale (VAS) were used to determine differences in snoring, daytime sleepiness, quality of life, side-effects of the appliances and patient preference. All patients underwent overnight domiciliary sleep recordings prior to and after fitting each appliance in order to objectively assess sleep quality in terms of the apnoea-hypopnoea index (AHI), snoring frequency and arterial oxygen saturation.The results suggested that there was no difference in the treatment performance of the TB and Herbst MAS for AHI (P = 0.71), snoring frequency (P = 0.49), arterial blood oxygen saturation (P = 0.97), quality of life and side-effects. The Herbst MAS proved to be the more effective appliance for reducing daytime sleepiness (P = 0.04) and was the more popular appliance among the patients. Side-effects with both appliances were minor and improved in the longer term. The TB MAS represents a viable alternative to the Herbst MAS in the treatment of patients with OSA.

PMID: 15743867 [PubMed - indexed for MEDLINE]

Maurice Berman Prize 2003.

J Orthod. 2004 Dec;31(4):279-87

Authors: McKeown HF

A crowded, high angle Class II case is presented and illustrated with stage clinical photographs. It was successfully treated with modified Twin Blocks and high pull headgear, extraction of all four first premolars, and upper and lower pre-adjusted edgewise appliances.

PMID: 15608342 [PubMed - indexed for MEDLINE]

Adaptive condylar growth and mandibular remodelling changes with bionator therapy--an implant study.

Eur J Orthod. 2004 Oct;26(5):515-22

Authors: Araujo AM, Buschang PH, Melo AC

The purpose of this study was to describe condylar growth and mandibular remodelling changes associated with bionator therapy. Twenty-five patients (15 males and 10 females) between 6.9 and 11.2 years of age with Class II division 1 malocclusions were randomly allocated to either control (n = 11) or treatment (n = 14; bionator only) groups and followed longitudinally for approximately 1 year. Treatment consisted of a bionator only, constructed to clear the buccal dentition by 2 mm and to position the mandible into an edge-to-edge incisor relationship. Using metallic implants for superimposition, mandibular growth, displacement, and true rotation were evaluated cephalometrically. The results showed significant changes in the direction (more posterior) but not in the overall amount of condylar growth. The bionator appliance produced greater than expected posterior drift of landmarks in the condylar and gonial regions. Cranial base superimposition showed greater than expected anterior mandibular displacement, but little or no true mandibular forward rotation with bionator therapy. The bionator appliance alone produced changes in condylar growth direction and remodelling changes associated with mandibular rotation and displacement.

PMID: 15536840 [PubMed - indexed for MEDLINE]

The William Houston Medal of the MOrth of the Royal College of Surgeons of Edinburgh 2003 and the BOS MOrth Cases Prize 2003.

J Orthod. 2004 Sep;31(3):169-80

Authors: O'Dwyer JJ

This paper describes the orthodontic treatment of 2 cases that were presented by the winner of the William Houston Medal of the MOrth of the Royal College of Surgeons of Edinburgh at the June 2003 diet of the examination. The cases were also successful presented for the British Orthodontic Society MOrth Cases Prize 2003.

PMID: 15489361 [PubMed - indexed for MEDLINE]

A clinical comparison of the quadhelix appliance and the nickel titanium (tandem loop) palatal expander: a preliminary, prospective investigation.

Eur J Orthod. 2004 Aug;26(4):411-20

Authors: Donohue VE, Marshman LA, Winchester LJ

Maxillary expansion using either a quadhelix appliance (Qx) or a nickel titanium palatal expander (Nt) was prospectively compared in 28 consecutive new patients (19 female, nine male) presenting with posterior buccal segment crossbites. Study models taken at each activation were measured to determine the mean maxillary expansion efficacy (Emax) and the mean expansion rate (m(max)) across the first molars and first premolars. Patient discomfort was assessed using visual analogue scores, and cost-effectiveness was also considered. Neither Emax nor m(max) differed significantly between Qx and Nt across either the first molars or the first premolars. However, both Emax and m(max) were significantly greater across the first molars than across the first premolars only with Qx (Emax: 8.4 +/- 0.7 mm versus 5.1 +/- 0.6 mm, P = 0.001; m(max): 0.09 +/- 0.005 mm/day versus 0.05 +/- 0.006 mm/day, P = 0.0001). In addition, greater variance was apparent in m(max) with Nt than with Qx across both the first molars and the first premolars. Overall, Qx and Nt elicited similar discomfort. However, significantly less was reported with Nt on days 6 (P = 0.04) and 7 (P= 0.03) following the second 'activation'. These preliminary results suggest that Qx and Nt are equally efficacious maxillary expanders. However, Qx expansion appeared significantly more controlled, as well as more individually predictable in expansion rate. Overall, Qx and Nt probably elicit similar discomfort, but significantly less discomfort may be seen with Nt following the second activation. Finally, because more than one appliance is invariably required with Nt, Qx expansion is potentially less costly.

PMID: 15366386 [PubMed - indexed for MEDLINE]

Dentoskeletal effects and facial profile changes during activator therapy.

Eur J Orthod. 2004 Jun;26(3):293-302

Authors: Cozza P, De Toffol L, Colagrossi S

The aim of this retrospective study was to investigate cephalometrically the skeletal, dental, and soft tissue modifications induced by activator treatment in patients with Class II malocclusions caused by mandibular retrognathism. The subjects, all in the mixed dentition, were selected from a single centre and were divided into two groups: 40 patients treated with an incisor double capping activator (20 girls, 20 boys with a mean age of 10 years) and a control group of 30 subjects (15 girls, 15 boys with a mean age of 10 years). The dentoskeletal and aesthetic changes that occurred were compared on lateral cephalograms taken before treatment (T0) and after 18-24 months, when the activator was removed (T1). In the control group the radiographs were obtained before (T0) and after (T1) 21 months (standard deviation +/- 3 months). Activator treatment in these growing patients resulted in a correction of the Class II relationship (ANB -2.14 degrees), a restriction of maxillary growth (SNA -0.5 degrees), an advancement of the mandibular structures (SNB +1.64 degrees, FH--NPg +3.39 degrees; OLp-B +5.17 mm, OLp-Pg +5.14 mm, OLp-Go +2.44 mm), a correction of the overjet (-5.03 mm), an improvement in overbite (-1.17 mm) and uprighting of the maxillary incisors (1--FH -5.64 degrees). The activator appliance was effective in treating growing patients with mandibular deficiency: activator therapy corrected Class II malocclusions by a combination of skeletal and dental changes and improved the soft tissue facial profile.

PMID: 15222715 [PubMed - indexed for MEDLINE]

An orthopaedic approach to the treatment of Class III malocclusions in the early mixed dentition.

Eur J Orthod. 2004 Apr;26(2):191-9

Authors: Cozza P, Marino A, Mucedero M

The aim of this investigation was to study cephalometrically the skeletal, dental and soft tissue modifications induced by a Delaire facemask and Bionator III appliance in a sample of 30 patients (17 boys and 13 girls), aged 4.1-9 years [mean 5.85 years, confidence interval (CI) 5.41-6.29], in the early mixed dentition with a skeletal Class III malocclusion caused by maxillary retrognathism (group 1) and compared with a control sample of 24 subjects (14 boys and 10 girls), aged 4-9 years (mean 5.97 years, CI 5.35-6.58) with untreated Class III malocclusions (group 2). For each patient a lateral cephalogram was taken before treatment (T0), after facemask removal (T1), and at the end of the retention period with a Bionator III (T2). Cephalometric analysis was carried out. The post-treatment cephalometric values in the treated group showed a forward displacement of the maxilla resulting in a statistically significant increase (P < 0.001) in the SNA angle, A-NPg (mm) and PNS-A (mm) linear values. There was a clockwise rotation of the mandible, with a decrease in the SNB angle and a satisfactory correction of the Class III relationship. The beneficial effects on the facial profile were confirmed by an increase in UL-EL distance and in NB--HL and NsPgs--HL angles, and by a decrease in the facial convexity angle. These findings indicate that the Delaire facemask and Bionator III treatment is effective for correcting skeletal Class III malocclusions caused by maxillary retrognathism in the early mixed dentition.

PMID: 15130043 [PubMed - indexed for MEDLINE]

Neovascularization and bone formation in the condyle during stepwise mandibular advancement.

Eur J Orthod. 2004 Apr;26(2):137-41

Authors: Leung FY, Rabie AB, H&#xE4;gg U

The aims of this investigation were to identify the temporal expression of vascular endothelial growth factor (VEGF) in the mandibular condyle and to correlate it with the pattern of new bone formation during stepwise mandibular advancement. Two hundred and fifty female, 35-day-old Sprague-Dawley rats were randomly divided into 10 groups, with 10 rats allocated to the single-step bite-jumping subgroup, 10 rats to the stepwise advancement subgroup and five rats to the control subgroup. In the experimental groups, the mandibles were kept in a continuous forward position. The initial stepwise advancement commenced on day 35, whereas the second advancement started on day 65. The rats were sacrificed on experimental days 3, 7, 14, 21, 30, 33, 37, 44, 51 and 60. Sections (7 microm) were cut through the condyle in the parasagittal plane and stained with anti-VEGF antibody. Each section was counter-stained with haematoxylin for observation of the cellular response. The sections were digitized and quantitatively analysed with a computer-assisted image analysing system. The results showed that the initial advancement in the stepwise group led to significantly less expression of VEGF when compared with single advancement. However, the second advancement on day 30 resulted in a significant increase in VEGF expression when compared with the one-step group and the natural growth control group. Thus, it was concluded that changes in the amplitude of mechanical loading, produced by stepwise advancement, have a significant effect on the production of VEGF by the chondrocytes. During the later stages of advancement, more VEGF and more condylar bone was produced.

PMID: 15130035 [PubMed - indexed for MEDLINE]

[A clinical study on improved herbst appliance]

Shanghai Kou Qiang Yi Xue. 2004 Feb;13(1):10-2

Authors: Gong Y, Shen G

PURPOSE:To observe the clinical effect of improved Herbst appliance. METHODS: Twelve patients with Class II malocclusion were selected and treated with improved Herbst appliance,The effects were observed and assessed after 6 to 8 months. The advantages and steps of this technique were also described. RESULTS:All the cases had satisfied and effective results with the help of improved Herbst appliance. The change of the ANB angle had statistical difference. CONCLUSION:Improved Herbst appliance is an be effective fixed functional appliance, it can used in adolescents (in the permanent dentition),postadolescents and young adults, instead of some orthognathic surgery especially in borderline skeletal Class II. This technique can easily be used in dental clinic.

PMID: 15007471 [PubMed - indexed for MEDLINE]

Treatment effects produced by the Bionator appliance. Comparison with an untreated Class II sample.

Eur J Orthod. 2004 Feb;26(1):65-72

Authors: Almeida MR, Henriques JF, Almeida RR, Almeida-Pedrin RR, Ursi W

The purpose of this retrospective investigation was to evaluate the dentoalveolar and skeletal cephalometric changes of the Bionator appliance on individuals with a Class II division 1 malocclusion. Lateral cephalograms of 44 patients were divided into two equal groups. The control group comprised 22 untreated Class II children (11 males, 11 females), with an initial mean age of 8 years 7 months who were followed without treatment for a period of 13 months. The Bionator group (11 males, 11 females) had an initial mean age of 10 years 8 months, and were treated for a mean period of 16 months. Lateral cephalometric headfilms were obtained of each patient and control at the beginning and end of treatment. The results showed that there were no changes in forward growth of the maxilla in the experimental group compared with the control group. However, the Bionator treatment produced a statistically significant increase in mandibular protrusion, and in total mandibular and body lengths. There were no statistically significant differences in craniofacial growth direction between the Bionator group and the control group, although the treated patients demonstrated a greater increase in posterior face height. The Bionator appliance produced labial tipping of the lower incisors and lingual inclination of the upper incisors, as well as a significant increase (P < 0.01) in mandibular posterior dentoalveolar height. The major effects of the Bionator appliance were dentoalveolar, with a smaller significant skeletal effect. The results indicate that the correction of a Class II division 1 malocclusion with the Bionator appliance is achieved not only by a combination of mandibular skeletal effects, but also by significant dentoalveolar changes.

PMID: 14994884 [PubMed - indexed for MEDLINE]

The effect of a modified reverse headgear force applied with a facebow on the dentofacial structures.

Eur J Orthod. 2004 Feb;26(1):51-7

Authors: G&#xF6;yenç Y, Ersoy S

The purpose of this study was to evaluate the effects of a modified reverse headgear force applied with a facebow on the dentofacial structures of patients with skeletal Class III malocclusions characterized by maxillary retrognathism. Thirty individuals before the pubertal peak and in the mixed dentition were selected. Fifteen subjects (seven males, eight females, mean age 9.2 years) who formed the treatment group were compared with a control group comprising seven males and eight females (mean age 8.6 years). Maxillary deficiency and negative overjet were noted in all individuals included in the treatment and control groups. The combination of a full coverage maxillary removable appliance and an embedded facebow was used for treatment. The outer arms of the facebow were bent to deliver the force through the approximate centre of resistance of the maxilla. Extra-oral elastics extended from the reverse headgear to the outer arms of the facebow. Statistical analysis indicated significant changes in angles SNA, NV-A, SV-ANS, SV-PNS and PP measurements, suggesting that the maxilla moved anteriorly. There was, however, no statistically significant difference in SN-MP, SN-PP and MP-PP measurements between the treatment and control groups. These results suggest that there was no maxillary or mandibular rotation, but that the molars moved mesially in the protraction group. The U6-PP(V) dimension did not display significant differences between the pre- and post-treatment measurements in the treated group. Anterior movement of the maxilla was obtained without rotation of the jaws and upper and lower maxillary heights were unaffected.

PMID: 14994882 [PubMed - indexed for MEDLINE]

[The feasibility and reliability of Pancherz's analysis in evaluating the treatment effects of bite-jumping on skeletal class II malocclusion]

Shanghai Kou Qiang Yi Xue. 2003 Aug;12(4):256-9

Authors: Chen RJ, Shen G

OBJECTIVE: This study was designed to conduct an in-depth evaluation on Pancherz's analysis. METHODS: A typical Class II case with bite-jumping therapy was selected for the whole process of Pancherz's Analysis. The skeletal growth modification and dental compensation were examined and portioned for their respective contribution to the correction of excessive overjet and Class II molar relationship. RESULTS: The following traits and properties of Pancherz's analysis were found: (1) A fixed reference system characterized by SN and OLp was established which led to an accurate detection of the moving objects. (2) Skeletal and dental changes were separated for evaluation, which resulted in a true assessment of the bite-jumping on growth pattern modification.(3) A segmental examination for dental changes indicated the magnitude of skeletal modification. Conclusion Pancherz's analysis is a feasible and reliable evaluation system which could reflect with accuracy the skeletal and dental effects caused by bite-jumping therapy.

PMID: 14966635 [PubMed - indexed for MEDLINE]

[Application of III-type bio-modulator in the reversed horizontal overbite of the deciduous dentition and mixed dentition]

Shanghai Kou Qiang Yi Xue. 2003 Oct;12(5):398-400

Authors: Qian L

PMID: 14966629 [PubMed - indexed for MEDLINE]

[Study of esthetic characteristic changes of soft tissue profile of patients with Angle Class division 1 malocclusion treated by functional regulator]

Shanghai Kou Qiang Yi Xue. 2003 Jun;12(3):167-9

Authors: Ye Q, Yang P, Zhao ZH, Zhao MY

OBJECTIVE: Five esthetic indexes were used to evaluate the soft tissue profile changes of patients with Angle Class division 1 malocclusion treated by Functional Regulator. METHODS: 21 patients with Angle Class division 1 malocclusion were treated by functional regulator. Pretreatment and posttreatment cephalograms of every patient were traced to analyze the esthetic characteristic of soft tissue profile. RESULTS: Most of the indexes tended to normal after treatment. CONCLUSION: Soft tissue profile of most patients with Angle Class division 1 malocclusion was improved after functional orthopedics while changes were different individually. Second stage treatment was still required for some patients.

PMID: 14661321 [PubMed - indexed for MEDLINE]

Temporomandibular response to early and late removal of bite-jumping devices.

Eur J Orthod. 2003 Oct;25(5):465-70

Authors: Chayanupatkul A, Rabie AB, H&#xE4;gg U

This study was designed to monitor the amount of bone formed after 'early' and 'late' removal of bite-jumping devices and to compare it with that of normal growth. One hundred and thirty-five 35-day-old female Sprague-Dawley rats were randomly divided into seven control (n = 5) and 10 experimental (n = 10) groups. Appliances were fitted to position the mandible forward in the experimental groups. On day 30, the bite-jumping device was removed in two groups ('early' removal) and the rats were sacrificed on days 44 and 60. On day 44 the device was removed in one group ('late' removal) and the rats were sacrificed on day 60. The full-time wear and matched control animals were then sacrificed at different time points. Tissue sections (7 microm) were cut through the temporomandibular joint (TMJ) in the sagittal plane and stained with periodic acid and Schiff's reagent for the evaluation of new bone formation. Newly formed bone was measured using a computer-assisted image analysing system. The results showed that, in the condyle, early removal of the appliance resulted in less bone formation when compared with that of natural growth. Late removal of the appliance resulted in bone formation similar to that of natural growth. In the glenoid fossa, the level of bone formation was similar to that of the control at early and late removal of the appliance. In conclusion, early appliance removal results in subnormal growth of the posterior condyle but not of the glenoid fossa. Increasing the length of mandibular advancement secures normal levels of mandibular growth in the post-treatment period.

PMID: 14609014 [PubMed - indexed for MEDLINE]

Pseudo-Class III malocclusion treatment with Balters' Bionator.

J Orthod. 2003 Sep;30(3):203-15

Authors: Giancotti A, Maselli A, Mampieri G, Spanò E

The aim of this article is to show the use of the Balters' Bionator in pseudo-Class III treatment. The importance of differentiating between true Class III and pseudo-Class III is emphasized. The therapeutic results of a Balters' Bionator appliance are presented in three case reports of subjects in the mixed dentition. In this stage of development it is possible to correct an isolated problem. The use of the Bionator III in this kind of malocclusion enabled the correction of a dental malocclusion in a few months and therapeutic stability of a mesially-positioned mandible encouraging favourable skeletal growth.

PMID: 14530417 [PubMed - indexed for MEDLINE]

Class III Twin Blocks: a case series.

J Orthod. 2003 Sep;30(3):197-201

Authors: Kidner G, DiBiase A, DiBiase D

OBJECTIVE: To evaluate the use of Class III Twin Blocks for the early treatment of Class III malocclusion. DESIGN: Retrospective analysis. Subjects and Method: 14 subjects were consecutively treated with a modified version of the Class III Twin Block appliance. Lateral cephalometric radiographs taken at the start and end of treatment were assessed digitally. RESULTS: The mean age of subjects was 10 years and mean treatment time was 6.6 months. The cephalometric analysis of changes during treatment shows proclination of the upper incisors [mean 5.1 degrees, SD 5.1], retroclination of the lower incisors [mean -4.5 degrees, SD 3.9], reduction in angle SNB [mean -1.3 degrees, SD 1.8] and an increase in the maxillary/ mandibular planes angle (mean 2.1 degrees, SD 2.2]. Average cephalometric digitizations and photographs of a clinical case are shown. CONCLUSIONS: Class III Twin Blocks can be used successfully for early treatment of Class III malocclusion. A randomly allocated prospective study is required to fully evaluate the efficacy of this appliance.

PMID: 14530416 [PubMed - indexed for MEDLINE]

Forward mandibular positioning up-regulates SOX9 and type II collagen expression in the glenoid fossa.

J Dent Res. 2003 Sep;82(9):725-30

Authors: Rabie AB, She TT, Harley VR

Regulatory factors governing the formation of bone in the glenoid fossa in response to functional appliance therapy have not been identified. Therefore, the purpose of this study was to investigate the temporal pattern of expression of two key chondrogenesis markers-SOX9 and its target gene, type II collagen-in the glenoid fossa by immunostaining in a 35-day-old Sprague Dawley rat model during both natural growth and forward mandibular positioning. The expression of both factors was up-regulated when the mandible was positioned forward, indicating an enhancement of chondrocyte differentiation and chondroid matrix formation. Our results indicate that chondroid bone formation in the glenoid fossa in response to forward mandibular positioning is regulated by molecular markers indicative of endochondral ossification.

PMID: 12939358 [PubMed - indexed for MEDLINE]

PTHrP regulates chondrocyte maturation in condylar cartilage.

J Dent Res. 2003 Aug;82(8):627-31

Authors: Rabie AB, Tang GH, Xiong H, H&#xE4;gg U

PTHrP is a key factor regulating the pace of endochondral ossification during skeletal development. Mandibular advancement solicits a cascade of molecular responses in condylar cartilage. However, the pace of cellular maturation and its effects on condylar growth are still unknown. The purpose of this study was to evaluate the pattern of expression of PTHrP and correlate it to cellular dynamics of chondrocytes in condylar cartilage during natural growth and mandibular advancement. We fitted 35-day-old Sprague-Dawley rats with functional appliances. Experimental animals with matched controls were labeled with bromodeoxyuridine 3 days before their death, so that mesenchymal cell differentiation could be traced. Mandibular advancement increased the number of differentiated chondroblasts and subsequently increased the cartilage volume. Higher levels of PTHrP expression in experimental animals coincided with the slowing of chondrocyte hypertrophy. Thus, mandibular advancement promoted mesenchymal cell differentiation and triggered PTHrP expression, which retarded their further maturation to allow for more growth.

PMID: 12885848 [PubMed - indexed for MEDLINE]

Contemporary treatment of a crowded Class II division 1 case.

J Orthod. 2003 Jun;30(2):119-26

Authors: Lowe CI

A 12-year-old Caucasian male presented with a severe Class II division 1 incisor relationship on a mild Skeletal II base with an average maxillary-mandibular planes angle and average lower facial height. Crowding was severe in the upper arch and moderate in the lower arch. Treatment was commenced using Twin Block appliances, and followed by extractions in all four quadrants and fixed appliances. This case illustrates the versatility of the Twin Block appliance in the treatment of those cases exhibiting crowding.

PMID: 12835427 [PubMed - indexed for MEDLINE]

The effect of Fränkel's function regulator type III on the apical base.

Eur J Orthod. 2003 Jun;25(3):311-8

Authors: Miethke RR, Lindenau S, Dietrich K

Dento-alveolar and skeletal effects of orthopaedic treatment have always been the subject of controversial scientific discussions. The objective of this retrospective study was to demonstrate the changes in the dental arch and the apical base of both jaws following therapy with Fränkel's function regulator type III (FR III). For this purpose, 42 Class III patients (28 females, 14 males, mean age 7.5 years) were selected according to strict criteria. The control group consisted of 16 patients (eight females, eight males, mean age 8.3 years) with minor malocclusion symptoms. Study models of all patients at the beginning and end of treatment were evaluated using a sophisticated measuring system. Apart from common parameters of model analysis, cusp inclination of the first molars, and apical bases of the maxilla and mandible were recorded to facilitate a comprehensive evaluation of treatment effects (including growth). The FR III stimulated the development of the maxilla, thus resulting in a more physiological growth pattern. Mandibular prognathism, however, was still discernible after therapy in the Class III patients, even though mandibular growth did not differ significantly between the two groups.

PMID: 12831222 [PubMed - indexed for MEDLINE]

Class II treatment effects of the Fränkel appliance.

Eur J Orthod. 2003 Jun;25(3):301-9

Authors: Janson GR, Toruño JL, Martins DR, Henriques JF, de Freitas MR

The objective of this work was to evaluate prospectively and cephalometrically the effects of the function regulator (FR) on dentoskeletal components during a treatment period of 28 months. The subjects consisted of 18 patients presenting with a Class II division 1 malocclusion, with a mean chronological age of 9 years 3 months at the beginning of treatment. The treated group was compared with a compatible control group of 23 untreated subjects observed during the same time period. Lateral cephalometric head films were obtained for the treated group at the beginning and after 28 months of treatment. The subjects in the control group belonged to a serial growth study sample from the Orthodontic Department at Bauru Dental School, University of São Paulo, for whom cephalometric head films were obtained annually from 4 to 18 years of age. The data for the control group were calculated from these head films. A student's t-test was used to compare the changes observed in the treated group with those in the control group. Differences were considered statistically significant at P < 0.05. The results demonstrated that the FR produced a statistically significant increase in the mandibular body, in the proportional size of the mandible to the maxilla and in lower anterior face height (LAFH); induced greater vertical development of the mandibular molars; reduced the overjet and overbite and produced an improvement in the molar relationship. Retrusion and palatal tipping of the maxillary incisors was also observed. However, the appliance did not produce any changes in maxillary development, in the growth pattern, or any improvement in the basal relationship. Therefore it was concluded that the effects of the FR in the correction of Class II malocclusions are primarily dento-alveolar, with a smaller participation of skeletal changes.

PMID: 12831221 [PubMed - indexed for MEDLINE]

Soft tissue changes in patients with Class II Division 1 malocclusions treated using Twin Block appliances: finite-element scaling analysis.

Eur J Orthod. 2003 Jun;25(3):225-30

Authors: Singh GD, Clark WJ

To determine changes in soft tissue profile in patients with Class II division 1 malocclusions treated with Twin Block appliances (TBA), 99 pairs of lateral cephalographs were traced and 25 soft tissue landmarks digitized. Procrustes superimposition was used to generate average soft tissue profiles scaled to an equivalent size. Statistical differences between prepubertal, pre- and post-treatment profiles were found using ANOVA (P < 0.001). Similarly, significant differences were found between adolescent, pre- and post-treatment profiles (P < 0.001). Using a colour-coded finite element scaling analysis (FESA) programme to localize size change, male prepubertal post-treatment configurations revealed local increases in size at the labiomental groove (approximately 25%) with negative allometry (size-related form change approximately 5%) in the labial and symphyseal regions. For the female prepubertal post-treatment configuration, local increases in size were conspicuous also at the labiomental groove (approximately 6%). Male adolescent post-treatment configurations revealed increases in size in the nasal, mental, and labiomental groove regions (approximately 18%) with negative allometries associated with the upper and lower lips (approximately 20%). For the female adolescent post-treatment configuration, the labial fissure showed an increase in size (approximately 17%), whereas the upper and lower lips and symphyseal region exhibited negative allometries (approximately 5-15%). For shape change, all soft tissue post-treatment configurations were highly isotropic (uniform shape change) over the entire facial nodal mesh except in the areas of the labiomental region and the labial fissure. Thus, in children and adolescents treated for Class II malocclusions a less pronounced labiomental groove is associated with using TBAs, which may provide a more effective anterior lip seal.

PMID: 12831211 [PubMed - indexed for MEDLINE]

The effects of activator treatment on the craniofacial structures of Class II division 1 patients.

Eur J Orthod. 2003 Feb;25(1):87-93

Authors: Basciftci FA, Uysal T, B&#xFC;yükerkmen A, Sari Z

The aim of the present study was to clarify the skeletal treatment effects induced by activator treatment. Fifty actively growing patients with Class II division 1 malocclusions were treated with an activator appliance. A control group consisting of longitudinal growth data from 20 patients (untreated Class II division 1 malocclusions) was used to eliminate possible differences in growth pattern. Lateral cephalograms of each patient were taken at the start and end of treatment. Final cephalograms were taken after a mean of 16.4 (+/- 2.0) months activator treatment, compared with a mean of 14.2 (+/- 2.4) months for the control group. Each cephalogram was traced and digitized by the same individual. The mean and standard deviations for linear and angular cephalometric measurements were analysed statistically, and intra- and inter-group changes were evaluated by paired- and independent-sample t-tests. At the end of the study period, the overjet was decreased in all patients. Ramus height, corpus length, anterior and posterior face height all increased significantly (P < 0.05). In the treatment group, ANB angle decreased and the bite was opened. The activator appliance caused maxillary incisor lingual tipping and mandibular incisor labial tipping. The overjet was decreased as a result of the increased forward growth of the mandible and dentoalveolar changes. The results demonstrated that the activator appliance has a characteristic skeletal and dental effect on the developing craniofacial complex.

PMID: 12608728 [PubMed - indexed for MEDLINE]

Evaluation of the effects of functional orthopaedic treatment on temporomandibular joints with single-photon emission computerized tomography.

Eur J Orthod. 2003 Feb;25(1):9-12

Authors: Güner DD, Oztürk Y, Sayman HB

The aims of this investigation were to evaluate the temporomandibular joints (TMJs) with single-photon emission computerized tomography (SPECT) in subjects treated with a mandibular advancement repositioning splint (MARS), and to compare the results with the total effect on dento-facial morphology. The study was undertaken on 17 Class II division 1 malocclusion subjects (nine males, eight females) with mandibular retrusion. Ten patients (five males, five females) formed the treatment group and seven (four males, three females) were used as the control. SPECT was performed only in the treatment group. Cephalometric evaluation showed significant increases in NAPog (P < 0.001) and SNB (P < 0.05) angles. Increased bone formation in theTMJs was analysed with the aid of pre- and post-treatment scintigraphic studies. The results indicate that new bone formation in the mandibular condyles seems to contribute to the increase in mandibular prognathism resulting from functional jaw orthopaedics.

PMID: 12608718 [PubMed - indexed for MEDLINE]

Effective temporomandibular joint growth and chin position changes: Activator versus Herbst treatment. A cephalometric roentgenographic study.

Eur J Orthod. 2002 Dec;24(6):627-37

Authors: Baltromejus S, Ruf S, Pancherz H

In 138 successfully treated Class II division 1 patients (40 Activator and 98 Herbst) effective temporomandibular joint (TMJ) growth changes (a summation of condylar remodelling, glenoid fossa remodelling, and condylar position changes within the fossa), and their influence on the position of the chin and the rotation of the mandible were analysed retrospectively. Lateral head films in habitual occlusion from before and after an average treatment period of 2.6 years for the Activator patients and 0.6 years for the Herbst patients were evaluated. Two different treatment changes were assessed: (1) overall growth changes and (2) treatment effects (overall growth changes minus age-related normal growth values: Bolton Standards). The comparison between the Activator and the Herbst group revealed larger effective TMJ and chin changes during Activator therapy due to the longer observation period (2.6 years versus 0.6 years). The treatment effects showed marked group differences for both the amount and direction of effective TMJ changes. The changes were vertical and slightly anterior in the Activator group, and predominantly posterior in the Herbst group. Concerning the chin changes, the treatment effects for the Herbst group exceeded those for the Activator group in both directions, caudally and anteriorly. The Activator group showed an anterior rotation and the Herbst group a slight posterior rotation of the mandible. The present investigation revealed that the effective TMJ and chin changes were increased by both Activator and Herbst treatment. However, the Herbst appliance renders more favourable sagittally orientated treatment effects in a much shorter period of time compared with the Activator.

PMID: 12512780 [PubMed - indexed for MEDLINE]

Proportional changes in cephalometric distances during Twin Block appliance therapy.

Eur J Orthod. 2002 Oct;24(5):485-91

Authors: Trenouth MJ

The aim of the study was to evaluate the cephalometric changes produced by the Twin Block appliance. Lateral cephalometric radiographs were taken before and after Twin Block appliance treatment on 30 consecutive patients (14 male, 16 female, mean age 12 years 6 months). Published normative data tables were used to produce control data, which were individually matched to the test group for age, sex, and treatment time. Alteration in shape was assessed by measuring percentage change in linear dimensions as opposed to change in cephalometric angles used in previous investigations. The differential average percentage change was calculated by subtracting the control value from the Twin Block value. Clinically significant changes (2 per cent and greater) were found in lower anterior (6.6 per cent) and posterior (4.6 per cent) face heights, upper incisor to maxillary plane (4.9 per cent), i.e. upper incisor retraction, and increase in mandibular length (Co-B 3.3 per cent, Co-Po 2.6 per cent, Ar-B 3.5 per cent, Ar-Po 2.2 per cent).

PMID: 12407944 [PubMed - indexed for MEDLINE]

Combined orthodontic-dentofacial orthopedic treatment of a Class II Division 2 patient with severe deep bite.

J Orthod. 2002 Sep;29(3):181-8

Authors: Wong RW

PMID: 12218194 [PubMed - indexed for MEDLINE]

The BOS intercollegiate M Orth prize of the Royal Colleges of England and Glasgow 2000.

J Orthod. 2002 Sep;29(3):173-80

Authors: Ismail S

PMID: 12218193 [PubMed - indexed for MEDLINE]

Changes in alveolar morphology during open bite treatment and prediction of treatment result.

Eur J Orthod. 2002 Aug;24(4):391-406

Authors: Beckmann SH, Segner D

It has been postulated that dentoalveolar height is enlarged by a compensation mechanism in long face subjects. In this study, dentoalveolar composition was studied in 83 open bite patients. It was found that increases in overbite during treatment coincided with vertical lengthening of the symphysis, which exceeded increments in lower face height. This vertical growth coincided mainly with an increase in the area of the symphysis. Furthermore, a retrusion of the maxillary incisors enhanced bite deepening. Stability of the overbite during the retention period was studied in a subset of 22 patients. It was found that retrusion of the maxillary incisors during treatment led to a more stable overbite during the retention period. Vertical lengthening of the symphysis relative to the increase in lower face height seemed to enhance bite opening during retention. Prediction of the overbite may be reliable, if a re-evaluation of the patients takes place during active treatment. The angle NTGoGn had a substantial predictive value (multiple R = 0.46) for post-treatment overbite. It is concluded that in open bite patients, a dentoalveolar compensation mechanism results in a stable overbite at the end of treatment by enlarging symphysial height through a moderate increase in symphysial volume. In addition, retrusion of the maxillary incisors contributes to overbite reduction. However, an excessive increase in vertical height of the symphysis relative to lower face height may relapse after active treatment. For prediction of the post-treatment overbite, the angle NTGoGn may be used, although a re-evaluation during treatment is recommended.

PMID: 12198869 [PubMed - indexed for MEDLINE]

Floating norms and post-treatment overbite in open bite patients.

Eur J Orthod. 2002 Aug;24(4):379-90

Authors: Beckmann SH, Segner D

In this study, the clinical significance of three floating norm systems, the Bergen Box (BB), the Segner-Hasund Harmonybox 1 and 2 (SHH1 and SHH2), as well as the influence of treatment modalities for predicting results of an open bite treatment were investigated. In the BB and SHH1, patients with a steep mandibular plane angle or a skeletal open bite configuration (O1mand, O1mandmax, O1max, or N1mand) were considered 'high risk', while in the SHH2, only the configurations O1mand and O1mandmax were considered high risk. All other configurations were designated 'low risk'. It was postulated that in high risk patients, the overbite was likely to relapse into an open bite after retention. Cephalograms of 83 open bite patients taken before treatment (T1) and at the end of retention (T2) were studied. Patients designated as low risk generally had a normal overbite at T2 after treatment, regardless of which box was used. The risk configurations of the SHH1 and SHH2 at T1 were significant predictors of the overbite at T2, the first being slightly better compared with the SHH2. The main clinical values of the SHH1 and SHH2 are strongly supported by the relatively good success rate in distinguishing a low-risk configuration. Reliable prediction of the treatment results of high-risk patients with risk configurations according to the SHH is improved by evaluating treatment modalities. The posterior bite splint seemed to have a bite opening effect, while a bite closing effect was associated with the use of a removable retention appliance.

PMID: 12198868 [PubMed - indexed for MEDLINE]

The British Orthodontic Society medal of the Intercollegiate M.Orth. of the Royal College of Surgeons of London and Glasgow 2001 and the William Houston medal of the M.Orth. of the Royal College of Surgeons of Edinburgh 2001.

J Orthod. 2002 Jun;29(2):83-95

Authors: Scholey J

PMID: 12114456 [PubMed - indexed for MEDLINE]

A comparative study of two mandibular advancement appliances for the treatment of obstructive sleep apnoea.

Eur J Orthod. 2002 Apr;24(2):191-8

Authors: Rose E, Staats R, Virchow C, Jonas IE

Mandibular advancement appliances (MAAs) are accepted as a treatment option for snoring and mild obstructive sleep disorders. In the present clinical study two differently designed devices were examined for their effectiveness in treating obstructive sleep apnoea (OSA). The study was based on an assessment of 26 patients with a polysomnographic diagnosis of mild OSA [22 men, four women; mean body mass index 27.3 kg/m2 (SD 3.1); mean age 56.8 years (SD 5.2); mean respiratory disturbance index (RDI): 16.0 events/hour (SD 4.4)]. After insertion of the first MAA and a 6-8-week habituation period, a cardio-respiratory home-sleep study was carried out. Following a 2-3-week period with no treatment, the second appliance was inserted. The sequence of the devices was randomized. Once the patients had become accustomed to the second appliance, another somnographic registration was carried out. Daytime sleepiness, snoring, and sleep quality were assessed subjectively on a visual analogue scale. The results showed that a statistically significant improvement in the respiratory parameters was achieved with both appliances (P < 0.01). However, the activator [RDI: 5.5 events/hour, SD 3.3; apnoea index (AI): 3.4 events/hour, SD 2.1] was significantly more effective (P < 0.01) than the Silencor (RDI, 7.3 events/hour, SD 5.3; AI: 5.8 events/hour, SD 3.2). No difference was recorded in the subjective assessment of the therapeutic effects. Both appliances reduced daytime sleepiness and snoring and improved sleep quality, and both influenced the treatment outcome.

PMID: 12001556 [PubMed - indexed for MEDLINE]