Invasive cervical resorption of central incisor during orthodontic treatment

ABSTRACT Introduction: Invasive cervical resorption (ICR) is a relatively rare type of ERR (External Root Resorption), in which a localized resorption begins in the cervical area of the tooth, below the epithelial junction and above the ridge crest. Objective: Describe the clinical case of an 11-year-old boy with no dental trauma history, presenting moderate crowding and ectopic eruption of the maxillary right central incisor. He had been undergoing orthodontic treatment elsewhere, and his family was dissatisfied with the results. Description: A new treatment was indicated, which included rapid maxillary expansion followed by extraction of four premolars. During routine panoramic evaluation, a radiolucid image was detected and a periapical radiograph was requested. At this point, an ICR of the maxillary right central incisor was found. The treatment was cautiously finalized and despite the use of light forces, central incisor was severally compromised by ICR and was therefore extracted. Conclusion: This clinical example discusses the importance of routine radiographs for the early diagnoses of ICR.

RESUMO Introdução: A reabsorção cervical invasiva (RCI) é um tipo relativamente raro de reabsorção radicular externa (RRE), no qual uma reabsorção localizada começa na região cervical do dente, abaixo da junção epitelial e acima da crista marginal. Objetivo: Descrever o caso clínico de um menino com 11 anos de idade, sem histórico de trauma dentário, apresentando apinhamento moderado e erupção ectópica do incisivo central superior. Ele realizava tratamento ortodôntico em outro local, mas sua família estava insatisfeita com os resultados. Descrição: Foi iniciado um novo tratamento, que incluiu a expansão rápida da maxila, seguida pela extração de quatro pré-molares. Durante a avaliação de rotina da radiografia panorâmica, uma imagem radiolúcida foi detectada, e uma radiografia periapical da região foi solicitada, sendo encontrada uma RCI no incisivo central superior direito. O tratamento foi finalizado com cautela e, apesar do uso de forças leves, o incisivo central estava seriamente comprometido pela RCI e, portanto, precisou ser extraído. Conclusão: Esse exemplo clínico discute a importância das radiografias de rotina para o diagnóstico precoce da RCI.

Correlation between temporomandibular joint morphometric measurements and gender, disk position, and condylar position.

OBJECTIVE: The aim of this study was to correlate the morphometric measurements of the temporomandibular joint, including condylar size, joint space, and articular eminence size, with gender, disk position, and condylar position by using magnetic resonance imaging. STUDY DESIGN: Overall, 93 patients were evaluated (31.2% males and 68.8% females; age 18-81 years; mean age 41 years). Condylar size (D1), joint space (D2), and eminence size (D3) were measured. Correlations with gender, disk position, and condylar position were calculated. RESULTS: A statistically significant correlation was found between D2 and gender, with the joint space being significantly larger in the male group (P = .05). There were correlations between D2 and the position of the disk and the position of the condyle (P ≤ .05). CONCLUSIONS: The results indicate a correlation between male gender and larger joint space. In addition, we found that the joint space size influences the articular disk and condyle position, which can cause disk displacement.

Cisto Odontogênico Ortoceratinizado: Relato de caso / Orthokeratinized Odontogenic Cyst: Case Report

O Cisto Odontogênico Ortoceratinizado (COO) é um cisto de desenvolvimento que ocorre nos maxilares, com maior predileção pela região posterior da mandíbula, em pacientes jovens do gênero masculino. O COO é caracterizado radiograficamente como uma área radiolúcida, unilocular bem definida e identificado histologicamente pela presença de uma cavidade cística fibrosa, revestida por epitélio estratificado pavimentoso ortoceratinizado. O tratamento do COO geralmente conservador, consiste na enucleação associada à curetagem óssea. O objetivo deste trabalho é relatar um caso de COO localizado em mandíbula... (AU)

The Orthokeratinized Odontogenic Cyst (OOC) is a developmental cyst that occurs in the jaws, with a greater predilection in the posterior region of the mandible in young male patients. OOC is characterized radiographically as a well-defined radiolucent, unilocular area and histologically identified by the presence of a fibrous cystic cavity lined by orthokeratinized squamous epithelium. Treatment of OOC is usually conservative and consists of enucleation associated with bone curettage. The objective of this study is to report a case of OOC located in the mandible... (AU)

The effect of different exposure parameters on proximal caries detection using the Kodak 9000 3D CBCT system / Efeito de diferentes parâmetros de exposição na detecção de cáries proximais usando o sistema Kodak 9000 3D TCFC

ABSTRACT Objective: The objective of study was to evaluate the diagnostic quality of CBCT images for caries lesions detection using different exposure parameters. Methods: Sixty extracted human teeth were selected and scanned using Kodak 9000 3D CBCT system, with the following exposure parameters combinations: 74 kV, 10mA; 74 kV, 12mA; 74 kV, 8 mA; 70 kV, 10 mA; 70kV, 12 mA; 70 kV e 8 mA; 70 kV, 6.3 mA. Two observers evaluated the images for caries presence using CS 3D Imaging Software. Each observer scored the proximal surfaces of each tooth on a 5-point scale. The scores were compared to histological sections used as gold standard. Accuracy for caries lesion detection was assessed for each exposure parameter combination and evaluated by means of ROC curve analysis. Results: The mean values for the areas under the ROC curves for each exposure parameter combination varied from 0.35 to 0.60. There was no statistical significant difference among protocols 1, 2, 4, 6 and 7. However, protocols 3 and 5 differed from all protocols. Conclusion: Although the highest dose protocol was the most efficient for proximal caries detection, the lowest dose protocol should be chosen based on the ALADA principle.

RESUMO Objetivo: Avaliar a qualidade de diagnóstico de imagens de TCFC para detecção de lesões de cárie utilizando parâmetros de exposição diferentes. Métodos: Sessenta dentes humanos extraídos foram selecionados e digitalizados usando o sistema Kodak 9000 3D TCFC, com as seguintes combinações de parâmetros de exposição: 74 kV, 10 mA; 74 kV, 12 mA; 74 kV, 8 mA70 kV, 10 mA; 70 kV, 12 mA; 70 kV e 8 mA; 70 kV, 6,3 mA. Dois observadores avaliaram as imagens para a presença de cárie utilizando o CS 3D Imaging Software. Cada observador pontuou as superfícies proximais de cada dente em uma escala de 5 pontos. Os escores foram comparados com cortes histológicos, utilizados como padrão-ouro. A precisão para detecção de lesões de cárie foi analisada para cada combinação de parâmetros de exposição e avaliada por meio de análise da curva ROC. Resultados: Os valores médios para as áreas sob as curvas ROC para cada combinação de parâmetro de exposição variou de 0,35-0,60. Não houve diferença estatística significativa entre os protocolos 1, 2, 4, 6 e 7. No entanto, os protocolos 3 e 5 diferem de todos os protocolos. Conclusão: Embora o protocolo de dose mais elevada foi o mais eficiente para a detecção da cárie proximal, o protocolo de dose mais baixa deverá ser escolhido com base no princípio ALADA.

Assessment of condyle position, fossa morphology, and disk displacement in symptomatic patients.

OBJECTIVE: The aim of the study was to determine whether there are any associations between the morphology of the glenoid fossa, articular spaces, and disk displacement by evaluating the magnetic resonance imaging (MRI) scans of symptomatic patients. Gender and age were also evaluated for any effect on the parameters. STUDY DESIGN: MRI scans of 199 temporomandibular joints were assessed for the morphology of the glenoid fossa and articular spaces in both sagittal and coronal views. The presence of disk displacement and its type in closed-mouth and open-mouth positions were also assessed. Analysis of variance (ANOVA), Tukey, and Student t tests or Mann-Whitney rank sum tests were used to investigate the associations among these variables. RESULTS: A total of 113 joints (56.8%) were presented with disk displacement. The articular spaces observed in sagittal and coronal views were, overall, significantly larger in males than in females in 3 of the 6 spaces (superior, posterior, and central spaces). Larger superior and medial articular spaces were associated with angled glenoid fossae. Higher mean values of the articular space sizes were associated with normal disk position (P < .001), except for the anterior articular space. When displacement was identified, higher values of the articular space sizes were also associated with disk reduction in the open-mouth position (P < .05). CONCLUSIONS: Condyles in the central position in the coronal view and slightly anteriorly positioned in the sagittal view are less likely to present disk displacement.

Relationship between articular eminence inclination and alterations of the mandibular condyle: a CBCT study.

This study aimed at verifying the correlation among angulation of the articular eminence (AE), shape of the condyle and its degenerative bone diseases (DBDs), according to age and sex, through Cone Beam Computed Tomography (CBCT). Five hundred and twenty-eight temporomandibular joints (TMJ) were evaluated. The condyles were classified as: flat, convex, angled and rounded, and the AE angulation was measured. The DBDs evaluated were osteophytes, flattening, erosion, subcortical cysts and spinal sclerosis. There was no difference in the mean angulations in relation to age group (p>0.05). In age groups of 60-69 years (p=0.003) and 70 years or over (p=0.021), the angulation was higher in males. There was an association between DBD and sex (p=0.047), in that the prevalence was higher in females. Differences in AE angles were not observed in condyles with one or no DBDs (p>0.05). However, the presence of two or more DBDs led to a decrease in the angle (p<0.05). Angled condyles showed higher AE angulations than the flat and convex types (p<0.01). In conclusion, the AE inclination is influenced by DBD and condyle shape; an association of two or more bone diseases in the condyle, or its flat or convex anatomy, results in a decrease in the angulation.

Relationship between articular eminence inclination and alterations of the mandibular condyle: a CBCT study

Abstract This study aimed at verifying the correlation among angulation of the articular eminence (AE), shape of the condyle and its degenerative bone diseases (DBDs), according to age and sex, through Cone Beam Computed Tomography (CBCT). Five hundred and twenty-eight temporomandibular joints (TMJ) were evaluated. The condyles were classified as: flat, convex, angled and rounded, and the AE angulation was measured. The DBDs evaluated were osteophytes, flattening, erosion, subcortical cysts and spinal sclerosis. There was no difference in the mean angulations in relation to age group (p>0.05). In age groups of 60-69 years (p=0.003) and 70 years or over (p=0.021), the angulation was higher in males. There was an association between DBD and sex (p=0.047), in that the prevalence was higher in females. Differences in AE angles were not observed in condyles with one or no DBDs (p>0.05). However, the presence of two or more DBDs led to a decrease in the angle (p<0.05). Angled condyles showed higher AE angulations than the flat and convex types (p<0.01). In conclusion, the AE inclination is influenced by DBD and condyle shape; an association of two or more bone diseases in the condyle, or its flat or convex anatomy, results in a decrease in the angulation.

Instalação de mini-implantes: qual a melhor imagem radiográfica para avaliação do espaço interradicular? / Mini-implants placement: which is the best x-ray imagine for interradicular

O objetivo desse estudo foi comparar a eficácia entre a tomografia computadorizada de feixe cônico (padrão-ouro) e as radiografias periapical, interproximal e panorâmica digitais para avaliação do espaço inter-radicular com vistas à instalação de mini-implantes. Métodos: a amostra foi composta por 40 sítios eleitos nos espaços inter-radiculares na região posterior. Os pontos de inserção para instalação dos mini-implantes foram representados por guta-percha em moldeira de acetato que os pacientes usavam durante as radiografias e a tomografia. Através do programa Adobe Acrobat 9 Pro Extend foram feitas medidas interradiculares no sentido horizontal nos três métodos radiográficos e comparadas com as da tomografia, que foram realizadas pelo Kodak Dental Imaging Software 3D. A comparação utilizou o coeficiente de Lin. Resultados: foi observada diferença estatisticamente significante entre a tomografia computadorizada e as radiografias panorâmicas (27,8% - P > 0,05). Conclusões: a radiografia interproximal foi o método mais preciso; a radiografia panorâmica e a periapical não são recomendadas para verificação do espaço inter-radicular, pois apresentaram alteração da dimensão dessa região no sentido horizontal.(AU)

The objective of this study was to compare the assessment of interradicular space for mini-implants fitting between the cone beam computed tomography (gold standard) and periapical, interproximal and panoramic digital radiographies. Methods: The sample consisted of 40 elected interradicular sites in the posterior area of five patients. These areas were represented by gutta percha points in acetate trays that patients used when radiographies and tomographies were taken. Horizontal measures, between dental roots, in three radiographic methods were obtained by Adobe Acrobat 9 Pro Extend program and compared with the tomography obtained by Kodak Dental Imaging Software 3D. The comparison was done by Lin coefficient correlation. Results: there was not stastistically difference between tomoghaphy and interproximal radiography (8,4% - p < 0,05). Conclusions: the interproximal radiography was the most accurate radiographic method; the panoramic and periapical radiographies are not recommended for interradicular space verification, because they present horizontal dimension alterations in this region. (AU)

Efficacy of a cone beam computed tomography metal artifact reduction algorithm for the detection of peri-implant fenestrations and dehiscences.

OBJECTIVE: To determine whether the use of a metal artifact reduction (MAR) algorithm improves the detection of peri-implant fenestrations and dehiscences on cone beam computed tomography scans. STUDY DESIGN: One hundred titanium fixtures were implanted into bovine ribs after the creation of defects simulating fenestrations and dehiscences. Images were acquired using four different protocols, namely, A2 (MAR on, voxel 0.2 mm), A3 (MAR on, voxel 0.3 mm), B2 (MAR off, voxel 0.2 mm), and B3 (MAR off, voxel 0.3 mm). For all protocols, receiver operating characteristic (ROC) curves were determined. Values for the areas under the ROC curves (Az) were subjected to analysis of variance. RESULTS: Az values were not statistically different among protocols regardless of the defect type (P > .05). CONCLUSIONS: The MAR algorithm tested by us did not improve the diagnosis of peri-implant fenestrations and dehiscences with use of either the 0.2 mm or the 0.3 mm voxel sizes.

Morphometric features of the mandibular condyle and association with disk abnormalities.

OBJECTIVE: The aim of this study was to evaluate the relationship between the morphometric characteristics of the condyle and temporomandibular joint (TMJ) disk displacement. STUDY DESIGN: One hundred and nine individuals who underwent magnetic resonance imaging of the TMJ were evaluated. Linear (D1: condyle width; D2: condyle thickness) and angular (A1: horizontal condylar angle; A2: anterior condylar angle; A3: medial condylar angle) measurements were made. These measurements were associated with articular disk displacement, with and without reduction. RESULTS: There was statistically significant association between limited D1 and D2 and between A1 above and A1 below the mean and displacement of the joint disk. There was statistically significant association between A2 and anterior displacement of the disk. Furthermore, thicker condyles and/or condyles with smaller horizontal angles and/or with smaller medial angles were associated with articular disk reduction. CONCLUSIONS: The morphometric characteristics of the bony components of the TMJ are related to articular disk displacement and with its reduction or nonreduction.

Skin Doses on the Lens for Temporomandibular Joint Exam in Cone Beam Computed Tomography

ABSTRACT The aim of this study was to evaluate the kerma at the surface of the lens in TMJ CBCT and to derive the equivalent dose. An anthropomorphic phantom of the head and neck manufactured by Radiation Support Devices (model RS-230) was used. The dosimetric measurements were obtained by using fourteen thermoluminescent dosimetry (TLD) dosimeters (LiF: Mg, Ti), divided in two pairs (one pair for each eye) and positioned on the surface of the phantom, per scanner evaluated. The tomographic images were acquired in three types of CBCT equipment (CS 9000, Gendex GXCB 500 and i-CAT). Values of equivalent dose obtained were: 5.82 mSv (CS 9000); 5.38 mSv (Gendex GXCB 500) and 7.98 mSv (i-CAT), which varied in accordance with the scanner and the exposure factors used in the image acquisition. The Gendex GXCB 500 used larger FOV and higher kV, resulting in levels close to those obtained on the CS 9000, while larger doses were associated with the i-CAT. The dose values associated with TMJ radiological procedures should be performed with awareness and appropriateness due to sensitivity of the lens.

Avaliação do dimorfismo sexual por meio de medidas lineares entre os processos mastoides e a espinha nasal anterior em crânios secos humanos / Evaluation of the sexual dimorphism by linear measurements between the mastoid process and the anterior nasal spine in human dry skulls

Objetivo ­ Desenvolver um novo método para a estimativa do sexo a partir de medidas entre os processos mastoides e a espinha nasal anterior em crânios secos humanos. Métodos ­ A amostra foi composta por 299 crânios, sendo 181 masculinos e 118 femininos, todos de indivíduos com idades conhecidas. Em cada crânio foram realizadas medidas lineares através de pontos craniométricos selecionados previamente. Foram realizadas as seguintes medidas: N-ENA (distância entre o násio e a espinha nasal anterior); PIMD-ENA (distância entre o polo inferior do processo mastóide direito e espinha nasal anterior) e PIME-ENA (distância entre o polo inferior do processo mastóide esquerdo e espinha nasal anterior). A partir da obtenção das medidas lineares, também foi determinada a uma área triangular, delimitada pela distância da espinha nasal anterior aos polos inferiores dos processos mastóides. Resultados ­ Pode-se observar que todas as distâncias lineares foram maiores no sexo masculino que no feminino e, consequentemente, a área triangular também foi maior. Houveram diferenças estatisticamente significativas entre todas as medidas realizadas de acordo com o dimorfismo sexual, bem como em relação a área triangular (P<0.05). Conclusão ­ O método proposto neste estudo pode ser utilizado para a determinação do dimorfismo sexual, onde os homens possuem medidas lineares maiores que as mulheres.

Objective ­ To develop a new method in order to estimate the sex although measurements between the mastoid processes to the anterior nasal spine in human dry skulls. Methods ­ The sample was composed of 299 skulls, being 181 male and 118 female, all of the individuals with the knowledge age. In each skull was performed linear measurements in selected craniometric points. It was performed the follow measurements: N-ANE (distance between the nasium and the anterior nasal spine); IPRMP-ANE (distance between the inferior polo of the right mastoid process and the anterior nasal spine) and IPLMP-ANE (distance between the inferior polo of the left mastoid process and the anterior nasal spine). Based on the linear measurements, it was determined was well as the triangular area, delimited by the anterior nasal spine and both mastoid processes. Results ­ It was possible to observe that all linear distances were higher in males than in females and, consequently, the triangular area. Statistical significant differences were observed in all measurements according to sex dimorphism, as well as in relation to the triangular area (P<0.05). Conclusion ­ The proposed method in this study could be used in order to determinate the sexual dimorphism, being the measurements in male higher than in females

Evaluation of temporomandibular joint disk displacement and its correlation with pain and osseous abnormalities in symptomatic young patients with magnetic resonance imaging.

OBJECTIVE: To evaluate the occurrence of temporomandibular joint disk displacement and its correlation with pain and osseous abnormalities using magnetic resonance imaging (MRI) in patients under 21 years of age. STUDY DESIGN: MRI images in open- and closed-mouth positions from 102 patients, under 21 years of age (mean age 17 years), were studied retrospectively. Patients were divided into six groups according to the disk-condyle relationship. Chi-square, Marascuilo procedure, and Cochran-Mantel-Haenszel tests were used to evaluate the relationships among pain, abnormalities, and the groups. RESULTS: There was a statistically significant correlation between bilateral disk displacement without reduction and pain (P = .011), and osseous changes (P < .0001). There was no proven link between pain and osseous abnormality (P = .414). CONCLUSION: Young patients are susceptible to all stages of disk displacement. There was a strong correlation only between each variable (osseous abnormalities and pain) and the most severe stage of disk displacement (bilateral disk displacement without reduction).

Avaliação subjetiva da aceitabilidade das imagens de tomografia computadorizada de feixe cônico para o planejamento de implantes osteointegrados / Subjective assessment of the acceptability of cone beam computed tomography images for the planning of osseointegrated implants

Introdução: Para realização de mensurações precisas para implantes osteointegrados, é necessário que as imagens tomográficas apresentem uma qualidade mínima, que permita a visualização clara das estruturas anatômicas. Objetivo: Diante disso, avaliou-se, subjetivamente, a aceitabilidade das imagens de diferentes protocolos de tomografia computadorizada de feixe cônico (TCFC), para o planejamento de implantes osteointegrados. Material e método: Foram obtidas imagens de TCFC de dez hemimandíbulas maceradas no equipamento K9000 3D, sendo modificada apenas a miliamperagem (Grupo I: 2 mA; Grupo II: 8 mA e Grupo III: 15 mA). As aquisições foram feitas com 80 kV, FOV de 5 × 3,7 cm, matriz de 512 × 512 e voxel de 0,076 mm de espessura. Após as aquisições, três avaliadores analisaram as reconstruções ortogonais em três tamanhos de voxel, constituindo-se, assim, nove grupos experimentais. Após a realização das mensurações de altura e espessura óssea, os avaliadores atribuíram escores (sim ou não) para a aceitabilidade das imagens para mensurações. Resultado: Os grupos apresentaram qualidade de imagem aceitável para o planejamento de implantes, com exceção das imagens adquiridas com 2 mA e analisadas com voxel de 0,076 mm e 0,535 mm. Conclusão: O protocolo de 8 mA e voxel de 2,1 mm deve ser, preferencialmente, indicado na identificação do canal mandibular, já que a dose de radiação é menor do que nos protocolos de 15 mA e a qualidade de imagem é superior aos protocolos de 2 mA; além disso, voxel de 2,1 mm apresentou maior aceitabilidade das imagens. .

Introduction: Performing accurate measurements for osseointegrated implant requires that the tomographic images show a minimum quality to allow adequate visualization of anatomical structures. Objective: Therefore, the acceptability of images of different Cone-Beam Computed Tomography (CBCT) protocols was assessed subjectively for the planning of osseointegrated implants Material and method: CBCT images of ten hemimandibles macerated in K9000 3D system were obtained, and only mA was modified (Group I: 2mA, Group II: 8mA and Group III: 15mA). All acquisitions were made with 80kV, FOV of 5 × 3.7 cm, matrix: 512 × 512 and voxel thickness of 0.076 mm. After the acquisitions, the orthogonal reconstructions were analyzed in three voxel sizes by three evaluators, thus making up nine experimental groups . Following bone height and thickness measurements, the evaluators scored (as yes or no) the acceptability of the images to be measured. Result: The groups presented acceptable image quality for implant planning, with the exception of the images acquired with 2mA and analyzed with voxel of 0.076 mm and 0.535 mm. Conclusion: The 8mA and 2.1 mm voxel protocol should preferably be indicated in the identification of the mandibular canal, as the radiation dose is lower than 15mA protocols and image quality is higher than 2 mA protocols. Additionally, 2.1 mm voxel showed a higher acceptability of images. .

Temporomandibular joint disk adhesion: evidence from magnetic resonance images / Adesão do disco da articulação temporomandibular: evidências em ressonância magnética

This case report has the aim to present an adhesion of the temporomadibular disc to the articular eminence, diagnosed on magnetic resonance imaging images. A 37-year-old female patient with TMJ (temporomandibular joint) disk adhesion on the left side and complaining of bilateral otalgia over the last 2 years is reported in the present article. The patient did not complain of articular pain or clicking, or any other noises of any nature. Clinical observation showed that the patient had restricted jaw opening, with mandibular deviation the left side without correction during mandibular movement. Our diagnostic impression was of partial anterior disk displacement with reduction of the right side disc; and partial anterior disk displacement with reduction and disc disk adhesion with hypo-mobility of the condyle, on the left temporomandibular joint. The peculiarity of this reported case is the fact that besides the bilateral partial anterior disc displacement, there was also found an adhesion of the disc on the left side. In conclusion, the magnetic resonance imaging exam of the temporomandibular joint can be considered an exam of choice for the evaluation of disc positioning and its morphological alterations.

Este trabalho tem como objetivo apresentar um caso clínico de adesão do disco da articulação temporomandibular à eminência articular, diagnosticada através da ressonância magnética. Paciente de 37 anos de idade, sexo feminino, com queixa de crises ocasionais de otalgia bilateral, ao longo dos últimos 2 anos. A paciente não referia dor ou ruídos articulares de qualquer natureza. Clinicamente, apresentava limitação de abertura de boca, com desvio à esquerda sem correção da trajetória ao final do movimento mandibular. A impressão diagnóstica foi de deslocamento anterior parcial, com redução, do disco articular direito; e, para o lado esquerdo, deslocamento anterior parcial, com redução, e adesão do disco articular ao componente temporal, com hipomobilidade do côndilo. A particularidade do caso descrito está justamente no fato de que além do deslocamento parcial anterior, bilateral, existia, também, uma adesão do disco no lado esquerdo. Conclui-se que o exame de ressonância magnética da articulação temporomandibular pode ser considerado o método de escolha para avaliação do posicionamento do disco articular e suas alterações morfológicas.

Evaluation of condyle defects using different reconstruction protocols of cone-beam computed tomography

This study was conducted to investigate how well cone-beam computed tomography (CBCT) can detect simulated cavitary defects in condyles, and to test the influence of the reconstruction protocols. Defects were created with spherical diamond burs (numbers 1013, 1016, 3017) in superior and/or posterior surfaces of twenty condyles. The condyles were scanned, and cross-sectional reconstructions were performed with nine different protocols, based on slice thickness (0.2, 0.6, 1.0 mm) and on the filters (original image, Sharpen Mild, S9) used. Two observers evaluated the defects, determining their presence and location. Statistical analysis was carried out using simple Kappa coefficient and McNemar's test to check inter- and intra-rater reliability. The chi-square test was used to compare the rater accuracy. Analysis of variance (Tukey's test) assessed the effect of the protocols used. Kappa values for inter- and intra-rater reliability demonstrate almost perfect agreement. The proportion of correct answers was significantly higher than that of errors for cavitary defects on both condyle surfaces (p < 0.01). Only in identifying the defects located on the posterior surface was it possible to observe the influence of the 1.0 mm protocol thickness and no filter, which showed a significantly lower value. Based on the results of the current study, the technique used was valid for identifying the existence of cavities in the condyle surface. However, the protocol of a 1.0 mm-thick slice and no filter proved to be the worst method for identifying the defects on the posterior surface.

Evaluation of buccal bone coverage in the anterior region by cone-beam computed tomography.

INTRODUCTION: The purpose of this study was to compare the sensitivity of diagnoses of buccal bone coverage in anterior teeth between axial and sagittal reconstructions using cone-beam computed tomography. METHODS: Five dry skulls were clinically evaluated to detect bone defects in the anterior maxilla and mandible to establish a gold standard. The skulls were prepared and placed on a Kodak 9000 3-dimensional scanner (Trophy, Marne La Vallée, France) for image acquisition. The images were processed and reconstructed using Kodak Dental Imaging software 3-dimensional module (version 2.4; Kodak Dental Systems, Atlanta, Ga). All bone defects were identified and recorded. RESULTS: In the sagittal and axial reconstructions, regions without bone coverage were diagnosed in 91.03% of cases as "cortex not seen" or "minimum thickness, fine, without marrow bone." CONCLUSIONS: Cone-beam computed tomography can help in the diagnosis of lack of bone coverage on the buccal surfaces of anterior teeth. There was no difference in the performance of the axial and sagittal reconstructions.

Enhancement cone beam computed tomography filters improve in vitro periimplant dehiscence detection.

OBJECTIVE: To investigate whether cone beam computed tomography filters would improve periimplant dehiscence detection. STUDY DESIGN: A hundred titanium implants were placed in bovine ribs in which defects simulating periimplant dehiscence had previously been created. After images acquisition, three oral radiologists assessed them with and without the following filters: Angio Sharpen high 5 × 5, Shadow, Sharpen 3 × 3, Sharpen Mild, and Smooth. The McNemar test verified the disagreement between all images versus the reference standard and original images versus images with filters; P < .05 was considered statistically significant. RESULTS: Dehiscence detection using the original images and the Shadow filter disagreed from the reference standard (P < .05), as well as when using the filters instead of the original images (P < .05). CONCLUSION: All the filters tested, with the exception of the Shadow, improved periimplant dehiscence detection. The Sharpen 3 × 3 filter was considered best for this task.

Detection of periimplant fenestration and dehiscence with the use of two scan modes and the smallest voxel sizes of a cone-beam computed tomography device.

OBJECTIVE: To assess the accuracy of cone-beam computed tomography (CBCT) in periimplant fenestration and dehiscence detection, and to determine the effects of 2 voxel sizes and scan modes. STUDY DESIGN: One hundred titanium implants were placed in bovine ribs in which periimplant fenestration and dehiscence were simulated. CBCT images were acquired with the use of 3 protocols of the i-CAT NG unit: A) 0.2 mm voxel size half-scan (180°); B) 0.2 mm voxel size full-scan (360°); and C) 0.12 mm voxel size full scan (360°). Receiver operating characteristic curves and diagnostic values were obtained. The Az values were compared with the use of analysis of variance. RESULTS: The Az value for dehiscence in protocol A was significantly lower than those of B or C (P < .01). They did not statistically differ for fenestration (P > .05). CONCLUSIONS: Protocol B yielded the highest values. The voxel sizes did not affect fenestration and dehiscence detection, and for dehiscence full-scan performed better than half-scan.

Análise da distância intercanina em relação ao fenótipo cor da pele e sua aplicação na identificação e interpretação de marcas de mordida / Analysis of intercanine distance with reference to skin color phenotype and its application to the identification and interpretation of bite marks

Introdução- Dentre as várias funções do Odontolegista, está a identificação e interpretação de marcas de mordidas. O objetivo deste estudo foi analisar a distância intercanina com relação ao fenótipo cor da pele, além de avaliar o nível de acerto e segurança da metodologia utilizada. Materiais e métodos - A população eleita foi composta por 600 indivíduos adultos, sendo 200 leucodermas, 200 faiodermas e 200 melanodermas. Estas medidas foram realizadas em modelos de gesso, com auxílio de um paquímetro digitalde precisão, tendo como referência as pontas das cúspides dos caninos. Resultados - Os resultados demonstraram que os indivíduos leucodermas apresentaram média inferior aos faiodermas e aos melanodermas e, por meio da análise discriminante, foram demonstradastaxas de erros de 72,67% para indivíduos faiodermas, 46% para leucodermas e 57,33% para melanodermas, com porcentagem total de erros de 58,67%. A regressão logística demonstrou um índice de associação entre probabilidade estimada e resposta observada de aproximadamente 5%. A metodologia utilizada apresentou um índice de confiabilidade de 99,87%. Conclusões - Assim, concluiu-se que a discriminação do fenótipo cor da pele a partir da distância intercanina não é um procedimento confiável e que o métodode aferição da distância intercanina aqui apresentado é simples, de baixo custo e eficaz.

Introduction - Among various functions of Forensic Dentist are the identification and interpretation of human bite marks. The aim of this study was to analyze the intercanine distance in the relation to skin color phenotype.In addition, the studies aimed at assess the level of reliability and validity of the research methodology used. Material and methods - The eligible sample comprised 600 adults, 200 leucoderma individuals, 200 faiodermas e 200 melanodermas. These measurements were performed on dental casts and accurately measured with a caliper, using as the reference the tips of the cusps of the canines. Results - The results showed that the leucoderma individuals presented a lower measurement on average than the faioderma and melanoderma individuals, and by discriminant analysis, error rates of 72.67% for faioderma, 46% for leucoderma and 57.33% for melanoderma individuals were demonstrated, with a total percentage error of 58.67%. Logistic regression demonstrated an index of association between estimated probability and observed response of approximately 5%. The methodology presented a reliabilityrate of 99.87%. Conclusion - Thus, we concluded that the discrimination of skin color phenotype considering intercanine distance is not a reliable procedure, and that the method of measuring intercanine presented here is simple, inexpensive and effective.