A method of gauging dental radiographs during treatment planning for dental implants.

J Contemp Dent Pract. 2007;8(6):82-8

Authors: Anil S, Al-Ghamdi HS

AIM: The goal of pre-surgical dental implant treatment planning is to position the optimum number and size of implant fixtures to achieve the best restorative results. The purpose of this article is to describe the use of radiographic imaging software to calibrate and measure anatomical landmarks to overcome inherent distortions associated with dental radiographs. The procedure along with its potential use as an adjunct to radiographic interpretation in routine clinical implant practice is presented. BACKGROUND: Diagnostic imaging is an essential component of implant treatment planning, and a variety of advanced imaging modalities have been recommended to assist the dentist in assessing potential sites for implants. Although technological advances have resulted in new imaging innovations for implant dentistry, dental radiography remains the most widely used tool for determining the quantity and quality of alveolar bone as it is a non-invasive procedure. However, the unreliable magnification factor associated with conventional radiographs remains a major problem when estimating the amount of bone available at the implant site. SUMMARY: This image measurement technique is capable of assessing the bone quantity by measuring the height and width of the alveolar crest for a specified region in a two dimensional plane in any direction related to the visible landmarks in the oral cavity. These measurements can be used by the clinician to select the type of implant and its position. Since there is no additional equipment or cost involved, the technique can be used as an important adjunct in implant practice.

PMID: 17846675 [PubMed - indexed for MEDLINE]

Digital subtraction technique for evaluation of peri-implant bone change in digital dental imaging.

Bull Tokyo Dent Coll. 2006 May;47(2):57-64

Authors: Wakoh M, Nishikawa K, Otonari T, Yamamoto M, Harada T, Sano T, Yajima Y, Ooguro T

The purpose of this study was to investigate digital subtraction technique in digital dental imaging for implant performance, used to quantitatively evaluate bone change around dental implants. For longitudinal assessment of peri-implant bone change, we applied subtraction technique to digital peri-apical radiographs using a digital dental imaging system in two cases at the upper canine and premolar regions. In both cases, we found two peaks of bone change at the crestal region; we also quantitatively demonstrated a marked change over the first one-month period and approximately three-month period spanning the fourth month to the end of the sixth month following implantation. Digital peri-apical radiography accommodating the digital subtraction program should be re-acknowledged as a reliable modality for assessing amount of bone change at local implantation sites.

PMID: 17167221 [PubMed - indexed for MEDLINE]

Reproducibility of pixel values for two photostimulable phosphor plates in consecutive standardized scannings.

Braz Oral Res. 2006 Jul-Sep;20(3):207-13

Authors: Freitas P, Yaedú RY, Rubira-Bullen IR, Escarpinati M, Vieira MC, Schiabel H, Lauris JR

The objective of the present study was to determine the reproducibility of the pixel values obtained with the Digora system (Soredex, Finland). Exposures were standardized, with variation in exposure and scanning time of two photostimulable phosphor plates containing a stepwedge image. The smallest variation in pixel values ranged from 50 to 75%, with the widest variations being observed in less dense steps. A significant difference in pixel values was observed in terms of X-ray exposure and scanning times and between the two plates themselves (ANOVA, p < 0.01). Using the present methodology, the reproducibility of pixel values was not satisfactory for the tested white photostimulable plates. This wide variation in digitalization might be influenced by the amount of X-rays that sensitized the plates. It may be important to establish the reproducibility of the pixel values in quantitative studies using digital image.

PMID: 17119702 [PubMed - indexed for MEDLINE]

For the dental patient: digital radiographs - imaging technology for the dental office.

J Am Dent Assoc. 2006 Nov;137(11):1624

Authors:

PMID: 17082288 [PubMed - indexed for MEDLINE]

Assessment of enamel demineralization using conventional, digital, and digitized radiography.

Braz Oral Res. 2006 Apr-Jun;20(2):114-9

Authors: Ferreira RI, Haiter-Neto F, Tabchoury CP, de Paiva GA, B&#xF3;scolo FN

This experimental research aimed at evaluating the accuracy of enamel demineralization detection using conventional, digital, and digitized radiographs, as well as to compare radiographs and logarithmically contrast-enhanced subtraction images. Enamel subsurface demineralization was induced on one of the approximal surfaces of 49 sound third molars. Standardized radiographs of the teeth were taken prior to and after the demineralization phase with three digital systems--CygnusRay MPS, DenOptix and DIGORA--and InSight film. Three radiologists interpreted the pairs of conventional, digital, and digitized radiographs in two different occasions. Logarithmically contrast-enhanced subtraction images were examined by a fourth radiologist only once. Radiographic diagnosis was validated by cross-sectional microhardness profiling in the test areas of the approximal surfaces. Accuracy was estimated by Receiver Operating Characteristic (ROC) analysis. Chi-square test, at a significance level of 5%, was used to compare the areas under the ROC curves (A(z)) calculated for the different imaging modalities. Concerning the radiographs, the DenOptix system (A(z) = 0.91) and conventional radiographs (A(z) = 0.90) presented the highest accuracy values compared with the other three radiographic modalities. However, logarithmically contrast-enhanced subtraction images (A(z) = 0.98) were significantly more accurate than conventional, digital, and digitized radiographs (p = 0.0000). It can be concluded that the DenOptix system and conventional radiographs provide better performance for diagnosing enamel subsurface demineralization. Logarithmic subtraction significantly improves radiographic detection.

PMID: 16878203 [PubMed - indexed for MEDLINE]

Digital imaging.

J Am Dent Assoc. 2006 Feb;137(2):152-3; author reply 153

Authors: Schiff T

PMID: 16521379 [PubMed - indexed for MEDLINE]

Digital imaging fiber-optic trans-illumination, F-speed radiographic film and depth of approximal lesions.

J Am Dent Assoc. 2005 Dec;136(12):1682-7

Authors: Young DA, Featherstone JD

BACKGROUND: Detection of early carious lesions is a prerequisite to an optimal preventive and minimal surgical intervention strategy. The authors conducted this study to determine whether Digital Imaging Fiber-Optic Trans-Illumination (DIFOTI) (Electro-Optical Sciences, Irvington, N.Y.) could be useful in evaluating early approximal lesions and to compare radiographs produced with F-speed film with both histologic lesion depth and cavitation. METHODS: The authors created artificial approximal lesions in vitro in extracted teeth over 14 weeks and imaged them using a "bitewing-like" view every two weeks with DIFOTI and F-speed radiographic film. At the end of the 14 weeks, the authors examined the lesions for surface cavitation using visual and tactile methods. They then thin-sectioned the lesions and subjected them to histologic analysis using polarized light microscopy (PLM). RESULTS: DIFOTI was not able to measure the depth of a lesion in any of the samples. It was, however, able to show surface changes associated with early demineralization as early as two weeks. The depth of a lesion measured using F-speed radiographic film was not statistically different from the depth of a lesion measured with PLM histologic analysis (P > .05). None of the lesions showed any signs of surface cavitation after 14 weeks of demineralization. CONCLUSIONS AND CLINICAL IMPLICATIONS: DIFOTI technology should not be used to decide between surgical or chemical treatment strategies based on lesion depth. We found that F-speed radiographic film was accurate in the approximating the depth of the lesion histologically. Ideally, the clinical decision whether to cut the tooth should be made based on cavitation rather than histologic lesion depth.

PMID: 16383050 [PubMed - indexed for MEDLINE]

Filmless imaging: the uses of digital radiography in dental practice.

J Am Dent Assoc. 2005 Oct;136(10):1379-87

Authors: van der Stelt PF

BACKGROUND: As use of digital radiography becomes more common, many dentists are wondering if and how they can replace conventional film-based imaging with a digital system. This article briefly describes the different technologies used for digital radiography in dentistry. The article provides general practitioners with a broad overview of the benefits and limitations of digital radiography to help them understand the role the technology can play in their practices. OVERVIEW: The two technologies now available are solid-state systems and phosphor plate systems. Each has its strong points, and the choice of which to use depends on the type of dental practice. Image processing improves the diagnostic quality of the radiographic information. Advanced image-processing techniques, such as subtraction radiography, are available for specialized clinics. CONCLUSIONS AND CLINICAL IMPLICATIONS: Digital radiography no longer is an experimental modality. It is a reliable and versatile technology that expands the diagnostic and image-sharing possibilities of radiography in dentistry. Optimization of brightness and contrast, task-specific image processing and sensor-independent archiving are important advantages that digital radiography has over conventional film-based imaging.

PMID: 16255462 [PubMed - indexed for MEDLINE]

Validation of two-dimensional measurements of root resorption craters on human premolars after 28 days of force application.

Eur J Orthod. 2005 Aug;27(4):390-5

Authors: Chan EK, Petocz P, Darendeliler MA

The aims of this study were to develop a three-dimensional (3D) mathematical model of a typical root resorption crater and to correlate two-dimensional (2D) surface area measurements to 3D volumetric measurements of root resorption craters created under light and heavy orthodontic forces. Data were obtained from a previous study of 36 first premolars from 16 subjects requiring extraction of these teeth as part of their orthodontic treatment. Buccal tipping forces of 25 or 225 g were applied for an experimental period of 28 days. After extraction, the samples were prepared for scanning electron microscopy (SEM) imaging, image processing and analysis. Surface area (2D) and volumetric (3D) measurements of all craters were obtained. A mathematical analysis of the 2D/3D relationship enabled the determination of an appropriate digital model for the shape, type and dimensions of resorption craters, which was also able to distinguish between a 'hemispheric' model versus a 'layered' model of craters.The results demonstrated that 2D and 3D measurements were strongly correlated (r = 0.991**). Within the light and heavy force groups, the measurements were also strongly correlated (r = 0.978** and r = 0.994**, respectively). For a 28 day experimental period, 2D measurements of root resorption craters were found to be as reliable as 3D measurements.

PMID: 16043475 [PubMed - indexed for MEDLINE]

Advances in digital technology and orthodontics: a reference to the Invisalign method.

Med Sci Monit. 2005 May;11(5):PI39-42

Authors: Melkos AB

BACKGROUND: Increased aesthetic demands during orthodontic treatment resulted in several treatment alternatives. However, the need to avoid conventional fixed orthodontic appliances led, with the use of computer-aided scanning, imaging, and manufacturing technology, to the development of new therapy concepts such as Invisalign. MATERIAL/METHODS: The Invisalign orthodontic technique involves a series of clear removable appliances and has been applied to correct a variety of malocclusions. RESULTS: The Invisalign method is an aesthetic orthodontic option for many patients, but it is suited mainly to adults or adolescents who have a fully erupted dentition and it has its indications and limitations. It handles simple to moderate non-extraction alignments better than mild to moderate extraction cases. The aligners are clear and therefore aesthetically ideal for the patient; they are comfortable to wear and, as they are removable, they provide simplicity of care and better oral hygiene. They also allow the evaluation of treatment options in detail before beginning treatment by using a virtual treatment model. It is also important to point out that this method has some disadvantages, which are associated with patient compliance, limited control over specific tooth movements, and additional documentation time. CONCLUSIONS: The Invisalign concept is an aesthetic alternative in orthodontic treatment, with advantages and disadvantages. It can be utilized to treat simple to moderate alignment cases, especially in adults, and serves as an additional part of the armamentarium of the orthodontist.

PMID: 15874904 [PubMed - indexed for MEDLINE]

Evaluation of the implantation position of mini-screws for orthodontic treatment in the maxillary molar area by a micro CT.

Bull Tokyo Dent Coll. 2004 Aug;45(3):165-72

Authors: Ishii T, Nojima K, Nishii Y, Takaki T, Yamaguchi H

The interalveolar septum between the upper first molar and the second premolar of the separated human maxillary bone was three-dimensionally observed by micro CT to evaluate the appropriate mini-screw type implant placement position by considering the relationship between the tooth roots and the maxillary sinus. After taking micro CTs of 5 human maxillary bones, horizontally sectioned images of the interalveolar septum area 2, 4, 6, 8, 10, and 12 mm deep from the crest of the alveolar ridge were reconstructed by three-dimensional reconstruction software. The bucco-lingual and mesio-distal lengths and area in each sectioned interalveolar septum were measured using digital image measurement software. Using the results, the interalveolar septum area between the upper first molar and the second premolar approximately 6-8 mm deep from the alveolar crest in the tooth root apical direction was determined to be the safest position for mini-screw implantation. Furthermore, lateral implantation from the palatal side was deduced to be the safest approach.

PMID: 15779459 [PubMed - indexed for MEDLINE]

OrthoCAD: digital models for a digital era.

J Orthod. 2004 Dec;31(4):344-7

Authors: Joffe L

This article describes the use of OrthoCAD--a digital study model capture, assessment and storage system. It is estimated that approximately 10% of orthodontists in USA and Canada now utilize digital study models, and improving technology is making it increasingly popular worldwide. The technology behind digital study models is briefly reviewed. The OrthoCAD system is described, and the advantages and disadvantages of using digital study models are highlighted.

PMID: 15608352 [PubMed - indexed for MEDLINE]

[Analysis of the measurement on of the maxillofacial soft tissue's parameters association with vertical dimension]

Shanghai Kou Qiang Yi Xue. 1997 Dec;6(4):219-21

Authors: Lu EY, Luo JP, Chang CY

The rehabilitation of vertical dimension of occlusion(VDO) exactly is one of the most important procedure for dental prosthesis in the field of prosthodontics.In this study,total of 19 subjects with normal range occlusion were selected.We measured 33 parameters relating to VDO of their facial soft tissue at intercusping position,with the technique of digital imaging analysis.The results as follows:we established a set of normal values of facial soft tissue parameters,which is suitable for the age group of 21-24 years old.It would provide an objective criterion for the rehabilitation of VDO.Also the normal values in this studies had been compared with other other studies,and it showed that the values of some parameters in our study,such as CH-CH',nasolabial angle were very close to oter data.Furthermore,it was found that both the position of the upper lip and the lower lip of the subjects were more anterior to that of white men,while the degrees of nasolabial and labiomental convexity were less obvious.

PMID: 15160199 [PubMed - as supplied by publisher]

Storage phosphor plates: how durable are they as a digital dental radiographic system?

J Contemp Dent Pract. 2004 May 15;5(2):57-69

Authors: Bedard A, Davis TD, Angelopoulos C

The aim of this in vitro investigation was to evaluate the durability of storage phosphor plates (SPPs) as a digital dental imaging system and to detect the factors that may contribute to possible reduced durability. A total of 140 new SPPs were divided into groups and exposed to the effects of the various handling steps during the image acquisition. An additional group of plates joined the existing plates in the Radiology Clinic and tested the additive effect of all these factors plus the effect of positioning the plates in a patient's mouth. The images resulting from these SPPs were regularly evaluated for the appearance of scratches as a sign of wear and rated by an oral radiologist using a 6 point scale. Although the manufacturer claims the SPPs can be used indefinitely, we found 95% of our plates were rendered non-diagnostic after only 50 uses. The manufacturer's claim for indefinite use of the SPPs seems to be questionable.

PMID: 15150634 [PubMed - indexed for MEDLINE]

A comparative study of the static and kinetic frictional resistance of titanium molybdenum alloy archwires in stainless steel brackets.

Eur J Orthod. 2004 Feb;26(1):105-11

Authors: Cash A, Curtis R, Garrigia-Majo D, McDonald F

This ex vivo study compared the static and kinetic frictional resistance of eight different archwires tested in a single, stainless steel, zero base 0.022 x 0.028 inch (0.56 x 0.711 mm) slot standard edgewise bracket. The archwires evaluated were 0.019 x 0.025 inch (0.483 x 0.636 mm) in dimension, manufactured from the following alloys: beta titanium (TMA), 'low friction' coloured beta titanium (aqua, honeydew, purple and violet), ion-implanted beta titanium, Timolium and a stainless steel control. Prior to friction testing, bracket and archwire dimensions were measured by direct digital imaging via a desktop computer linked to a binocular light microscope. Frictional force was evaluated using an Instron universal testing machine. All experiments were carried out at room temperature, with no ligation, in the dry state with 20 degrees of added torque. The results demonstrated that static and kinetic friction were statistically significant (P < 0.001) for all archwire types. Ion-implanted and standard TMA archwires were found to have no significant advantage over stainless steel. The archwire alloys may be ranked as follows: stainless steel produced the lowest frictional resistance followed by honeydew, ion-implanted TMA and Timolium, with aqua, purple and violet producing frictional resistance values as high as standard TMA. It was also found that the percentage difference between the archwire and bracket slot dimensions claimed by the manufacturers and those measured in this experiment produced tolerances ranging from +5.37 to -6.67 per cent.

PMID: 14994890 [PubMed - indexed for MEDLINE]

[The application of oral digital imaging system in root canal measurement and filing]

Shanghai Kou Qiang Yi Xue. 2003 Dec;12(6):413, 421

Authors: Zhang F

PMID: 14966577 [PubMed - indexed for MEDLINE]

Comparison of direct digital and conventional intraoral radiographs in detecting alveolar bone loss.

J Am Dent Assoc. 2003 Nov;134(11):1468-75

Authors: Khocht A, Janal M, Harasty L, Chang KM

BACKGROUND: Intraoral radiographs are important diagnostic aids in periodontics. The authors conducted a study to compare estimates of bone levels from direct digital and conventional radiographic under normal clinical use. METHODS: A full-mouth series of conventional radiographs was taken for each of 25 subjects who had periodontitis. A long cone paralleling technique was used for periapical, or PA, images, and a paper sleeve with biting tab was employed for bitewing, or BW, images. A set of direct digital radiographs matching the conventional radiographs was taken for each subject under the same conditions. The distance from the cementoenamel junction to the interproximal alveolar crest on all readable surfaces was measured. RESULTS: Examiners measured 857 PA image sites and 315 BW image sites matched on both radiographic systems. Paired t test showed significant differences in bone levels between the two systems. Measurements from conventional PA images were higher in all maxillary sextants (P < or = .02), and measurements from digital PA images were higher in mandibular anterior sextants (P = .007). Measurements in digital BW images were higher in mandibular posterior sextants (P = .002). A chi2 analysis of categorical bone levels (normal, early-to-moderate loss or advanced loss) showed significant differences between the imaging systems in revealing bone levels in both PA (P < .04) and BW (P < .001) images. Digital radiographs showed a higher number of sites with bone loss than did conventional radiographs. CONCLUSIONS: Under normal clinical use, alveolar bone levels revealed on intraoral direct digital radiographs differ from those revealed on conventional radiographs. CLINICAL IMPLICATIONS: Intraoral direct digital radiographs are not an equivalent substitute for conventional radiographs in evaluating alveolar bone levels.

PMID: 14664265 [PubMed - indexed for MEDLINE]

Assessment of the accuracy of a three-dimensional imaging system for archiving dental study models.

J Orthod. 2003 Sep;30(3):219-23

Authors: Bell A, Ayoub AF, Siebert P

OBJECTIVE: The use of stone and plaster study models is an integral part of any dental practice and is required for research. Storage of study models is problematic in terms of space and cost. Ayoub et al.(1) introduced a new technique based on the recent advances in stereophotogrammetry for archiving dental study models in a digital format. However, assessment of the accuracy of the generated three-dimensional (3D) models has not been carried out yet. It was the aim of this study to evaluate the accuracy of this technique. DESIGN: A comparative assessment between direct measurements of dental study models and measurements of computer generated 3D images of the same study models was performed. MATERIALS AND METHODS: Twenty-two dental study models stored at Glasgow Dental Hospital and School for the purposes of research were used in the study. The models were captured in three dimensions using a photostereometric technique and stored in digital format. MAIN OUTCOME MEASURES: Measurements were conducted directly on dental study models and on the computer generated 3D images using Euclidean Distance Matrix Analysis.(2) The difference between the two sets of measurements was statistically analysed using a two-sample t-test. RESULTS: The average difference between measurements of dental casts and 3D images was 0.27 mm. This difference was within the range of operator errors (0.10-0.48 mm) and was not statistically significant (P < 0.05). CONCLUSION: This study shows that it is possible to use 3D imaging to store dental study models for treatment monitoring and research with a satisfactory degree of accuracy.

PMID: 14530419 [PubMed - indexed for MEDLINE]

Measurement of the optical density of packable composites: comparison between direct and indirect digital systems.

Pesqui Odontol Bras. 2002 Oct-Dec;16(4):299-307

Authors: Graziottin LF, da Costa NP, da Silveira ID, Veeck EB

The aim of this study was to measure the optical density of four packable composite resins with widths of 1, 2, 3 and 4 mm, by means of Digora (direct) and DentScan DentView (indirect) digital imaging systems, in order to compare both methods. Twenty acrylic plates, with the proposed thicknesses, were used, each one containing a sample of each resin. Each acrylic plate was radiographed three times, under a standardized technique. For the Digora system, an optical plate was used under each resin sample, and, for the DentScan DentView system, occlusal films were employed, totalizing 60 exposures for each system. Optical plates and films were scanned and three consecutive optical readouts were carried out, totalizing 1,440 readouts. The results were submitted to statistical analysis and revealed that the average optical density of the four resins always increased as thickness increased. Regarding the comparisons between the composite resins, in both analysis the resin with the greater optical density was Surefil followed by Prodigy Condensable, Alert and Solitaire . The correlations between the results of Digora and DentScan DentView were significant for the different thicknesses and materials. The observed tendency is that as the values obtained with the Digora system increase, so do the values obtained with DentScan DentView . While thickness increased, the values of optical density in both Digora and DentScan DentView tended to approach each other. The Digora system presented smaller amplitude between the results obtained in adjacent thicknesses.

PMID: 12612767 [PubMed - indexed for MEDLINE]

The technologically well-equipped dental office.

J Am Dent Assoc. 2003 Jan;134(1):30-41

Authors: Schleyer TK, Spallek H, Bartling WC, Corby P

BACKGROUND: Information technology, or IT, applications for dental practice continue to develop rapidly. More than 85 percent of all dentists use computers in their offices, and the number of clinical uses for the computer is on the rise. This article discusses the state of the art of several technologies, provides an integrative view of a technologically well-equipped office and offers several guidelines for technology purchasing decisions. CONCLUSIONS: Most administrative applications are relatively mature and are required for the smooth functioning of today's dental offices. Clinical applications--such as dental and medical health histories, charting, digital imaging, diagnostic and treatment applications, and decision support--vary in their degree of maturity. Most Internet applications-such as Internet-based scheduling and e-mail communication with patients--still are an optional adjunct for dental practices. PRACTICE IMPLICATIONS: Practitioners should develop a comprehensive plan for implementing or updating the IT infrastructure in their offices. Issues to be considered in technology purchasing decisions include usability, integration, work flow support, cost-benefit analysis and compliance with standards.

PMID: 12555955 [PubMed - indexed for MEDLINE]

Panoramic and cephalometric extraoral dental radiograph systems.

J Am Dent Assoc. 2002 Dec;133(12):1696-7

Authors:

The basic unit is the Orthopantomograph OP100, which is a computer-controlled extraoral imaging system capable of producing panoramic radiographs using either film or digital technology. This unit has automatic exposure control, automatic spine compensation, a patented V-shaped X-ray beam and a built-in quality assurance program. The OP100 is available with cephalometrics (the OC100 model), linear tomography (the Ortho Trans model), identification film marking (the Ortho ID model) and imaging software (the Ortho Zone and Ortho TMJ models). The addition of a cephalometric arm to the Orthopantomograph makes the unit an Orthoceph. The image receptor sizes are as follows: Panorama OP100: cassette 15 x 30 centimeters; Cephalometric image receptor OC100: 24 x 30 cm, 18 x 24 cm, 8 x 10 inches; Panoramic image receptor OP100D: CCD camera, image pixel size 90 x 90 micrometers; Cephalometric image receptor OC100D: CCD camera, image pixel size 90 x 90 microm.

PMID: 12512672 [PubMed - indexed for MEDLINE]

Digital radiography: an overview.

J Contemp Dent Pract. 2002 Nov 15;3(4):23-39

Authors: Parks ET, Williamson GF

Since the discovery of X-rays in 1895, film has been the primary medium for capturing, displaying, and storing radiographic images. It is a technology that dental practitioners are the most familiar and comfortable with in terms of technique and interpretation. Digital radiography is the latest advancement in dental imaging and is slowly being adopted by the dental profession. Digital imaging incorporates computer technology in the capture, display, enhancement, and storage of direct radiographic images. Digital imaging offers some distinct advantages over film, but like any emerging technology, it presents new and different challenges for the practitioner to overcome. This article presents an overview of digital imaging including basic terminology and comparisons with film-based imaging. The principles of direct and indirect digital imaging modalities, intraoral and extraoral applications, image processing, and diagnostic efficacy will be discussed. In addition, the article will provide a list of questions dentists should consider prior to purchasing digital imaging systems for their practice.

PMID: 12444400 [PubMed - indexed for MEDLINE]

Two decades of computerized information technologies in dental radiography.

J Dent Res. 2002 Sep;81(9):590-3

Authors: Wenzel A

PMID: 12202637 [PubMed - indexed for MEDLINE]

Capabilities of computerized clinical decision support systems: the implications for the practicing dental professional.

J Contemp Dent Pract. 2002 Feb 15;3(1):27-42

Authors: Umar H

This article presents the use of captured data within the range of patient care activities of the dental practitioner with an emphasis on prosthodontic activities. It describes the use of computer technology in dentistry during a typical patient encounter in a dental care facility. The oral health record, the need for speech recognition technology, and existing documentation software are discussed. Ongoing development of the capabilities of Clinical Decision Support (CDS) systems is becoming an important part of the oral health setting; including systems applicable to prosthodontics. These systems all rely on a common standardized structure for the electronic (oral) health record (EHR/EOHR). Current developments in radiological technology and digital imaging are explained as well as fundamentals of decision support systems clarified. Recent developments in the representation of domain knowledge as well as the implementation of a dental nomenclature and metathesaurus are also presented. A quality matrix identifies target values for dental informatics while demonstrating an "importance-weighting" of dental characteristics.

PMID: 12167911 [PubMed - indexed for MEDLINE]

Helical axis errors affect computer-generated occlusal contacts.

J Dent Res. 2002 May;81(5):338-43

Authors: DeLong R, Ko CC, Olson I, Hodges JS, Douglas WH

A helical axis describing mandibular motion can be calculated from two distinct positions of the mandible; however, as these positions come closer together, calculation errors increase. This study investigated the effects of errors in the calculated helical axis on simulated mandibular motion by the measurement of changes in occlusal contacts. A standard helical axis was calculated from a simulated lateral movement. A series of digital interocclusal records from centric to a 5 degree mandibular rotation about the standard helical axis was created. Digital dental cast models were aligned to the interocclusal records. Helical axis parameters and occlusal contacts calculated with the use of the aligned digital models were compared with those of the standard. Helical axes calculated from mandibular positions separated by 1.5 degrees to 5.0 degrees yielded equivalent occlusal contacts. Qualitatively, contacts for helical axes calculated from jaw rotations of 0.7 degrees or larger were nearly identical to those of the standard.

PMID: 12097448 [PubMed - indexed for MEDLINE]

Comparisons of physical imaging properties among three kinds of imaging plates used in photostimulable phosphor systems for dental radiography.

Bull Tokyo Dent Coll. 2002 Feb;43(1):23-30

Authors: Nishikawa K, Ooguro T, Kuroyanagi K

The purpose of this study was to compare the physical imaging properties of three kinds of imaging plates (IPs) used with two photostimulable phosphor systems for dental radiography: HR-V, used with the Digora, BAS-SR, and ST-V, used with the DenOptix for intraoral radiography and panoramic radiography, respectively. Sensitivity to X-ray, gradient, modulation transfer function (MTF), noise power spectrum (NPS), noise-equivalent quanta (NEQ), and detective quantum efficiency (DQE) were compared. All imaging plates were read using the DenOptix scanner with inactive automatic range control (ARC). The scanning resolution was set at 300 dpi. Decay of image information by room light was also compared at inactive and active ARC settings. BAS-SR showed the lowest sensitivity, the lowest gradient, the highest MTF, and the highest NPS. ST-V showed the highest sensitivity, the highest gradient, the lowest MTF, and the lowest NPS. HR-V was the second best for all imaging properties examined in this study. NEQ and DQE of BAS-SR were lowest, and those of ST-V were highest at low spatial frequencies. However, BAS-SR showed relatively constant NEQ and DQE while those of ST-V decreased remarkably at high spatial frequencies. NEQ and DQE of HR-V were the second best at low spatial frequencies and the best at high spatial frequencies. Therefore, we concluded that HR-V has the best imaging properties for dental radiography among three kinds of IPs evaluated in this study. However, the light decay speed of image information with HR-V was remarkably faster than with BAS-SR. To adopt HR-V for a system with which IPs are treated in an ordinary room, the light decay should be taken into account.

PMID: 12013822 [PubMed - indexed for MEDLINE]

An introduction to digital radiography in dentistry.

J Orthod. 2002 Mar;29(1):66-9

Authors: Brennan J

The aim of this article is to explain the basic principles of digital radiography, and to discuss the intra- and extra-oral imaging systems currently available. There are two main types of digital sensors available. One is based on charge coupled device technology and the other consists of phosphor storage plates. The advantages and disadvantages of each are highlighted with particular attention to orthodontics.

PMID: 11907314 [PubMed - indexed for MEDLINE]

Vertebral artery dissection due to indirect neck trauma : an underrecognised entity.

Neurol India. 2001 Dec;49(4):384-90

Authors: Prabhakar S, Bhatia R, Khandelwal N, Lal V, Das CP

Vertebral artery dissection is an important cause of brain stem stroke, especially in the young. Dissections of carotid and vertebral arteries in neck account for about 20% of strokes in young compared with 2.5% in the elderly. Three patients of vertebral artery dissection related to indirect neck trauma are described. The first patient developed the symptoms while dancing, the second after a trivial fall and the third while he was on a dental chair. None of them had a direct severe neck trauma or concomitant risk factor like hypertension, connective tissue disease or migraine. Clinical symptomatology was similar in all the patients and included occipito-nuchal pain, headache and brain stem dysfunction chiefly in the posterior inferior cerebellar artery (PICA) territory. One of the patients also had associated ischaemic myelopathy. MRA and DSA confirmed dissection in all with a predominant steno-occlusive picture. Cases of so called trivial neck movement/torsion related dissection have been described previously but have not received any major importance. Usually classified as 'spontaneous' or 'traumatic', there is a possible ambiguity in literature about appropriate terminology. We emphasise that a history of such subtle precipitating events be taken while diagnosing young patients with brain stem strokes, to recognise this clinical entity. Although mechanisms are not absolutely clear, yet there seems to be an important relationship between arterial dissection and neck movements or minor trauma.

PMID: 11799413 [PubMed - indexed for MEDLINE]

Emerging methods of caries diagnosis.

J Dent Educ. 2001 Oct;65(10):1001-6

Authors: Stookey GK, Gonz&#xE1;lez-Cabezas C

Current diagnostic tools used in dental caries detection are not sensitive enough to diagnose the disease process in its early stages and, frequently, once a diagnosis is made, restoration is the only effective means of treatment. The purpose of this review was to systematically assess the available literature for evidence to determine if emerging diagnostic methods for dental caries are more efficient than traditional methods for detecting and monitoring the progress of caries in permanent and primary teeth. Inclusion and exclusion criteria were established preceding the literature search. Included articles were grouped by type of emerging technology and study design. The types of emerging technologies included laser fluorescence, light fluorescence, digital imaging fiber optic transillumination, and ultrasound. Primarily on the basis of in vitro and preclinical data, some of the reviewed methodologies showed promising results for the detection and monitoring of early caries lesions. However, very little clinical data are available to validate these emerging technologies. It was concluded that, although significant promise is apparent with these technologies, there is not enough evidence available at this time for any of the reviewed diagnostic techniques to be recommended as a substitute for traditional diagnostic techniques.

PMID: 11699969 [PubMed - indexed for MEDLINE]

Digital imaging modalities for dental practice.

Bull Tokyo Dent Coll. 2001 Feb;42(1):1-14

Authors: Wakoh M, Kuroyanagi K

The introduction of the computed tomograph in the 1970s revolutionized medical diagnosis by initiating the transition from analogue to digital imaging. During this period, more specialized equipment for image processing was developed, such as cathode-ray tubes for image display, special sensors for image acquisition, and storage devices for image archiving. Digital imaging systems designed exclusively for use in dentistry were developed in the latter half of the 1980s. Some are now being clinically applied under conditions of close scrutiny to determine diagnostic accuracy, image quality, and radiation exposure to patients. This article reviews the enabling technologies of digital systems used in dentistry, and focuses upon intraoral digital imaging systems, concepts for digital image acquisition, and variations in radiation dose and their effects on diagnostic accuracy of caries detection.

PMID: 11484791 [PubMed - indexed for MEDLINE]

Dental CT imaging: a look at the jaw.

Radiology. 2001 May;219(2):334-45

Authors: Abrahams JJ

The jaw comprises two complex bony structures: the mandible and maxilla. Their curved or archlike configuration makes radiographic imaging difficult. Furthermore, the superimposition of dense teeth and roots may obscure underlying tissues, and streak artifacts from dental restorations often degrade computed tomographic (CT) images. Recently, dental CT reformatting programs that use thin transverse images of the jaw to reformat multiple panoramic and cross-sectional views were developed. Since images are reformatted, streak artifacts that degrade bone visualization at direct coronal CT are projected over the crowns of the teeth, permitting optimal viewing of bone. As a result, these programs have been successfully used to evaluate implants, cysts, tumors, and surgical procedures. They have created not only a new modality for viewing the jaw but also a new partnership between dentists and radiologists. Questions that cannot be answered in the dentist's office with conventional radiographs are now answered in radiology departments with dental CT scans. The objective of this article is to trace, with a series of examples, the effect that this imaging modality has had on radiographic evaluation of the jaw and to provide the reader with knowledge that should enable him or her to become more involved in imaging of the jaw.

PMID: 11323454 [PubMed - indexed for MEDLINE]

Applications of Scanora multimodal maxillofacial imaging in orthodontics.

Br J Orthod. 1998 Feb;25(1):15-20

Authors: Roberts-Harry D, Carmichael FA

The principles of the Scanora multimodal radiography system are described. This self-contained unit of X-ray generator, patient chair, and imaging elements incorporates the two basic principles of narrow beam radiography and spiral tomography. Conventional panoramic images or magnified images of the dentition can be produced. In orthodontics, the application of spiral tomography in order to obtain cross sectional images has proved helpful in the assessment of a number of patients. Four cases are reported in which the images obtained using this system has substantially contributed to their management.

PMID: 9547970 [PubMed - indexed for MEDLINE]

Advanced imaging methods.

Crit Rev Oral Biol Med. 1996;7(4):346-95

Authors: Matteson SR, Deahl ST, Alder ME, Nummikoski PV

Recent developments in imaging sciences have enabled dental researchers to visualize structural and biophysical changes effectively. New approaches for intra-oral radiography allow investigators to conduct densitometric assessments of dento-alveolar structures. Longitudinal changes in alveolar bone can be studied by computer-assisted image analysis programs. These techniques have been applied to dimensional analysis of the alveolar crest, detection of gain or loss of alveolar bone density, peri-implant bone healing, and caries detection. Dental applications of computed tomography (CT) include the detailed radiologic anatomy of alveolar processes, orofacial soft tissues and air spaces, and developmental defects. Image analysis software permits bone mass mineralization to be quantified by means of CT data. CT has also been used to study salivary gland disease, injuries of the facial skeleton, and dental implant treatment planning. Magnetic resonance imaging (MRI) has been used extensively in retrospective and prospective studies of internal derangements of the temporomandibular joint. Assessments based on MRI imaging of the salivary glands, paranasal sinuses, and cerebrovascular disease have also been reported. Magnetic resonance spectroscopy (MRS) has been applied to the study of skeletal muscle, tumors, and to monitor the healing of grafts. Nuclear imaging provides a sensitive technique for early detection of physiological changes in soft tissue and bone. It has been used in studies of periodontitis, osteomyelitis, oral and maxillofacial tumors, stress fractures, bone healing, temporomandibular joint, and blood flow. This article includes brief descriptions of the technical principles of each imaging modality, reviews their previous uses in oral biology research, and discusses potential future applications in research protocols.

PMID: 8986396 [PubMed - indexed for MEDLINE]

Accuracy of visual inspection, fiber-optic transillumination, and various radiographic image modalities for the detection of occlusal caries in extracted non-cavitated teeth.

J Dent Res. 1992 Dec;71(12):1934-7

Authors: Wenzel A, Verdonschot EH, Truin GJ, K&#xF6;nig KG

Occlusal caries lesions may progress into the dentin without this resulting in a macroscopic breakdown of the enamel surface. Imaging methods may therefore be needed to aid in the visual detection of occlusal caries. It was the aim of this study to evaluate diagnostic accuracy in a laboratory set-up of visual inspection (VI), fiber-optic-transillumination (FOTI), conventional radiography (CR), and two digital radiographic image modalities (DRm and DRr) for detection of occlusal caries in clinically non-cavitated teeth. Eighty-one extracted third molars from 18-20-year-old males were assessed by four observers on a five-rank confidence scale by the five methods. Ground sections (500-600 microns) served as validation for true state of disease: 1 = no caries in dentin, 2 = caries just beyond dentino-enamel junction, or 3 = deep dentinal caries, halfway or more to the pulp. ROC analysis was performed on the basis of the confidence rank scale data on two diagnostic thresholds, T1 = caries in dentin (disease state 2+3) and T2 = caries deep in dentin (state 3). On the T1 level, use of the FOTI method gave on average the most accurate diagnosis, closely followed by VI, both performing better than use of radiography. On the T2 level, all five diagnostic methods performed equally well.

PMID: 1452897 [PubMed - indexed for MEDLINE]