A system for automatic classification of endodontic treatment quality in CBCT.

OBJECTIVES: An evaluation of the effectiveness of a new computational system proposed for automatic classification, developed based on a Siamese network combined with Convolutional Neural Networks (CNNs), is presented. It aims to identify endodontic technical errors using Cone Beam Computed Tomography (CBCT). The study also aims to compare the performance of the automatic classification system with that of dentists. METHODS: One thousand endodontically treated maxillary molars sagittal and coronal reconstructions were evaluated for the quality of the endodontic treatment and the presence of periapical hypodensities by three board-certified dentists and by an oral and maxillofacial radiologist. The proposed classification system was based on a Siamese network combined with EfficientNet B1 or EfficientNet B7 networks. Accuracy, sensivity, precision, specificity, and F1-score values were calculated for automated artificial systems and dentists. Chi-square tests were performed. RESULTS: The performances were obtained for EfficienteNet B1, EfficientNet B7 and dentists. Regarding accuracy, sensivity and specificity, the best results were obtained with EfficientNet B1. Concerning precision and F1-score, the best results were obtained with EfficientNet B7. The presence of periapical hypodensity lesions was associated with endodontic technical errors. In contrast, the absence of endodontic technical errors was associated with the absence of hypodensity. CONCLUSIONS: Quality evaluation of the endodontic treatment performed by dentists and by Siamese Network combined with EfficientNet B7 or EfficientNet B1 networks was comparable with a slight superiority for the Siamese Network. CLINICAL RELEVANCE: CNNs have the potential to be used as a support and standardization tool in assessing endodontic treatment quality in clinical practice.

Influence of the Milliamperage and Artifact Reduction Tool on the CBCT-Based Diagnosis of Buccal and Lingual Peri-implant Dehiscences: Comparison Between Two Types of Implants.

PURPOSE: To evaluate the influence of the milliamperage and artifact reduction (AR) tool on the diagnosis of buccal and lingual peri-implant dehiscences related to titanium-zirconia (Ti-Zr) and zirconia (Zr) implants using CBCT images. MATERIALS AND METHODS: Ti-Zr and Zr implants were alternately inserted in 20 sites in the posterior region of three human mandibles that presented intact cortical (control) bones or simulated buccal and/or lingual peri-implant dehiscences. CBCT images were acquired with an OP300 Maxio unit, varied milliamperage (5 and 8 mA), and the use of AR tool. Three oral radiologists assessed the presence of dehiscences using a 5-point scale. The area under the receiver operator characteristic curve (Az), sensitivity, and specificity of each group (control and dehiscence) were obtained and compared using multiway ANOVA (α = .05). RESULTS: The milliamperage and the AR tool did not influence the diagnosis of dehiscences, and there were no differences between the buccal and lingual cortices (P > .05). However, Zr implants showed a higher sensitivity (0.67 to 0.89) and lower specificity (0.26 to 0.44) than Ti-Zr implants (0.19 to 0.44 and 0.93 to 1.00, respectively; P < .05). Az values did not differ between the implant types (P > .05). CONCLUSIONS: Dehiscences were more detectable when related to Zr implants, while the absence of dehiscences was more correctly visualized adjacent to Ti-Zr implants. The use of varied milliamperages and the AR tool did not affect the diagnosis of peri-implant dehiscences, regardless of the involved cortical (buccal or lingual) bones.

Influence of kilovoltage-peak and the metal artifact reduction tool in cone-beam computed tomography on the detection of bone defects around titanium-zirconia and zirconia implants.

Purpose: The aim of this study was to assess the influence of kilovoltage-peak (kVp) and the metal artifact reduction (MAR) tool on the detection of buccal and lingual peri-implant dehiscence in the presence of titanium-zirconia (Ti-Zr) and zirconia (Zr) implants in cone-beam computed tomography (CBCT) images. Materials and Methods: Twenty implant sites were created in the posterior region of human mandibles, including control sites (without dehiscence) and experimental sites (with dehiscence). Individually, a Ti-Zr or Zr implant was placed in each implant site. CBCT scans were performed using a Picasso Trio device, with variation in the kVp setting (70 or 90 kVp) and whether the MAR tool was used. Three oral radiologists scored the detection of dehiscence using a 5-point scale. The area under the receiver operating characteristic (ROC) curve, sensitivity, and specificity were calculated and compared by multi-way analysis of variance (α=0.05). Results: The kVp, cortical plate involved (buccal or lingual cortices), and MAR did not influence any diagnostic values (P>0.05). The material of the implant did not influence the ROC curve values (P>0.05). In contrast, the sensitivity and specificity were statistically significantly influenced by the implant material (P<0.05) with Zr implants showing higher sensitivity values and lower specificity values than Ti-Zr implants. Conclusion: The detection of peri-implant dehiscence was not influenced by kVp, use of the MAR tool, or the cortical plate. Greater sensitivity and lower specificity were shown for the detection of peri-implant dehiscence in the presence of a Zr implant.

Automatic exposure compensation in intraoral digital radiography: effect on the gray values of dental tissues.

BACKGROUND: This study aimed to investigate the effect of automatic exposure compensation (AEC) of intraoral radiographic systems on the gray values of dental tissues in images acquired with or without high-density material in the exposed region using different exposure times and kilovoltages. The influence of the distance of the high-density material was also investigated. METHODS: Radiographs from the molar region of two mandibles were obtained using the RVG 6100 and the Express systems, operating at 60 and 70 kV and 0.06, 0.10, and 0.16 s. Subsequently, a titanium implant was inserted in the premolar's socket and other images were acquired. Using the ImageJ software, two regions of interest were determined on the enamel, coronary dentine, root dentine, and pulp of the first and second molars to obtain their gray values. RESULTS: In the RVG 6100, the implant did not affect the gray values (p > 0.05); the increase in kV decreased it in all tissues (p < 0.05), and the exposure time affected only the root dentine and pulp. In the Express, only enamel and coronary dentine values changed (p < 0.05), decreasing with the implant presence and/or with the increase in exposure factors. The distance of the implant did not affect the results (p > 0.05). CONCLUSIONS: AEC's performance varies between the radiographic systems. Its effect on the gray values depends not only on the presence or absence of high-density material but also on the kV and exposure time used.

Morphological Study of Root Canals of Maxillary Molars by Cone-Beam Computed Tomography.

The aim of this study was to evaluate the root canal morphology of permanent maxillary molars by cone-beam computed tomography (CBCT) using the classifications of Weine et al. and Vertucci and to correlate the findings with sex, age, position in the dental arch, and prevalence of a second canal in the mesiobuccal root (MB2). A total of 414 scans were evaluated, corresponding to 1,000 teeth. The assessment consisted of coronal, axial, and sagittal reconstructions using i-CAT Workstation®. Type 0 was assigned when neither classification could be applied. The data were entered into an Excel spreadsheet and analyzed using SPSS. The chi-squared test or Fisher's exact test was used to compare the distribution of root canal morphology classified using the two systems. Analysis of the distribution of Weine types showed a predominance of type III in mesiobuccal roots, while type 0 predominated in distobuccal and palatal roots. Vertucci type IV predominated in mesiobuccal and distobuccal roots and type VII in palatal roots. There was no difference in the distribution of morphological canal types in permanent maxillary molars evaluated by CBCT according to sex, age group, or position in the dental arch of the patients. MB2 canals were identified in 68.4% of the teeth evaluated.

Identifying misconceptions about oral radiology and medicine among dental students.

PURPOSE/OBJECTIVES: Misconceptions are learning deficiencies that can lead to inappropriate clinical decision-making in dental practice. Although misconceptions are common among students, they are rarely analyzed in dental education. Thus, this study aimed to identify and analyze students' misconceptions about oral radiology and medicine at a Brazilian dental school. METHODS: Between October 2019 and March 2020, a self-administered anonymous questionnaire was distributed to dental students at the Federal University of Pernambuco, Brazil, which comprised multiple-choice questions about oral radiology and medicine. The questions were divided into two groups: 10 knowledge-based questions (less demand for reasoning) and five scenario-based questions (higher demand for reasoning). The students' responses were assessed for correctness (correct or incorrect) and confidence (sure or unsure), while misconceptions were identified when a student was sure of an incorrect response. Pearson's chi-square test was used to analyze the variables (α = 0.05). RESULTS: A total of 1380 responses were collected. Misconceptions represented 24.3% (n = 336) of the total responses and 56.8% of the incorrect responses. The mean misconceptions per student were 3.7 (range, 0-8). Students who chose incorrect answers tended to have higher confidence levels (p < 0.001). Moreover, misconceptions were more frequent for scenario-based questions (25.7%) than for knowledge-based questions (23.7%) (p = 0.000). CONCLUSION: A large number of misconceptions existed among participants. Our findings will aid educators and students in identifying misconceptions and planning measures to prevent and correct them.

Radiographic diagnosis of proximal caries is not affected by exposure protocols and presence of high-density material on systems with automatic exposure compensation.

OBJECTIVES: To investigate the performance of radiographic systems with automatic exposure compensation (AEC) on the caries diagnosis in images acquired with different exposure parameters and in the presence of high-density material. Also, the image quality was assessed. METHODS: Forty posterior teeth (80 proximal surfaces) were radiographed using a phosphor plate and a CMOS system. Images were acquired with different exposure times (0.06, 0.10 and 0.16 s) and kilovoltages (60 and 70kVp), in the absence and presence of high-density material in the X-rayed region (control and high-density groups). Five radiologists assessed the caries using a 5-point scale. Diagnostic values were compared using two-way ANOVA. RESULTS: For both radiographic systems, there were no significant differences in the area under the ROC curve (0.60-0.73), sensitivity (0.79-0.87) and specificity (0.29-0.48) between the control and high-density groups, exposure times or kilovoltages (p > 0.05). For image quality, scores assigned to the control and high-density groups were similar in each exposure protocol in both systems. CONCLUSIONS: The presence of high-density material, exposure time and kilovoltage did not affect the caries diagnosis in any of the systems tested. It is recommended to use protocols with lower doses to reduce the patient's exposure.

Self-regulated learning perception of undergraduate dental students during the COVID-19 pandemic: A nationwide survey in Brazil.

BACKGROUND: This study aimed to evaluate the perception of self-regulated learning of Brazilian undergraduate dental students during the COVID-19 pandemic. MATERIAL AND METHODS: A nationwide cross-sectional survey was conducted. Data were collected in 2020, through an anonymous self-administered virtual questionnaire, which comprised an initial section related to the students' sociodemographic data, category of educational institution where they enrolled, and the possible impacts of COVID-19 pandemic on family income, teaching activities (maintained remotely or totally suspended), and self-perception of academic performance during e-learning. The second part comprising 31 questions related to the adapted Self-Regulated Learning Perception Scale (SRLPS). For statistical analysis, Student's t-test of independent samples, Kruskal-Wallis, and Mann-Whitney U test were used, considering a significance of 5%. RESULTS: From 779 students, 425 (54.6%) reported distance learning activities during the pandemic, and 354 (45.4%) experienced complete interruption of teaching activities. Students with good performance during e-learning were more skilled in self-regulated learning when compared to those who reported regular (p = 0.026), bad (p = 0.000), and very bad (p = 0.000) performance. In addition, students who stated a good performance during e-learning were more skilled in self-regulated learning than those with fully suspended teaching activities (p = 0.000). CONCLUSIONS: E-learning performance of undergraduate dental students during COVID-19 pandemic influenced the self-regulated learning perception. In addition, the pandemic negatively impacted the self-regulated learning of students who experimented full suspension of teaching activities. Changes in family's income did not affect their self-regulated learning. Key words:Dental education, community health, e-learning, learning, pandemics.

The impact of the COVID-19 pandemic on undergraduate and graduate dental courses in Brazil.

BACKGROUND: The COVID-19 pandemic has raised challenges in adapting to teaching and learning methods in dental education. OBJECTIVE: This study aimed to evaluate the impact of the COVID-19 pandemic on the academic activities of undergraduate (UDG) and graduate (GD) dental students in Brazil. Additionally, students' perceptions and attitudes toward teaching activities during this period were analyzed. METHODS: A nationwide cross-sectional survey was conducted with a sample of Brazilian UDG and GD dentistry students. Data were collected in 2020 through an online, self-administered, and anonymous questionnaire, which comprised 26 questions related to demographic data, activities of the college, family and individual student income, and attitudes and perceptions about e-learning during the pandemic. The data were tabulated and analyzed using descriptive statistics. RESULTS: The sample included 1,166 students (779 UDG and 387 GD). Among these, 425 (54.6%) UDG and 270 (69.8%) GD students remotely participated in teaching activities, of which 42.6% of the UDG considered their performance in e-learning to be bad or very bad and 49.8% of the GD regarded it as good or excellent. The survey also showed that 354 (45.4%) UDG and 102 (26.4%) GD expressed a desire to discontinue the course following the outbreak of the pandemic. Among the GD, 225 (58.4%) said that their experiments were completely interrupted. CONCLUSIONS: This study reveals the poor perception and performance of dental students regarding e-learning. Additionally, the findings suggest a negative impact of the pandemic on dental education in Brazil. Effective measures should be taken to mitigate these significant consequences.

Effect of the incorporation of silica blow spun nanofibers containing silver nanoparticles (SiO2/Ag) on the mechanical, physicochemical, and biological properties of a low-viscosity bulk-fill composite resin.

OBJECTIVE: This work aimed at producing silica-blow-spun nanofibers containing silver nanoparticles (SiO2/Ag) and investigating the effect of their incorporation in different proportions, with or without pre-treatment with a silane coupling agent, on the mechanical, physicochemical, and biological properties of a commercial composite low-viscosity bulk-fill resin. METHODS: The production of SiO2/Ag nanofibers was confirmed by transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDX). A portion of the produced nanofibers was silanized. Scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), contact angle measurements, and agar diffusion tests against Streptococcus mutans were used to verify the differences between silanized and non-silanized nanofibers. Different proportions (0.5 wt% and 1 wt%) of silanized (SiO2/Ag-0.5S and SiO2/Ag-1S) and non-silanized (SiO2/Ag-0.5NS and SiO2/Ag-1NS) nanofibers were incorporated into the bulk-fill composite (Opus Bulk Fill Flow, FGM). A commercial composite was used as the control. Evaluation of the color parameters (L*, a*, and b*), radiopacity, contact angle, antimicrobial activity, Vickers microhardness, surface roughness (Sa and Sq), flexural strength, and SEM of the fractured surfaces were performed. The data were analyzed using the Mann-Whitney U test (fiber morphology), Kruskal-Wallis tests, with Dunn's post hoc test (antimicrobial activity of the specimen against S. mutans), Student's t-test (disk diffusion), one-way ANOVA and Tukey (color, radiopacity, and contact angle), and two-way ANOVA and Tukey (microhardness, surface roughness, and flexural strength) tests. All statistical analyses were performed at a significance level of 1% (α = 0.01). RESULTS: Porous nanometric SiO2/Ag fibers were successfully produced. The silanization process, confirmed by FTIR, increased the diameter and contact angle and reduced the growth inhibition halos of the nanofibers (p < 0.01). After the incorporation of nanofibers into the dental composite, all color parameters were altered in all the experimental groups (p < 0.01). All the groups presented adequate radiopacity values. No statistical difference was observed in the contact angles of the experimental composites (p > 0.01). The lowest microbial counts were obtained in the SiO2/Ag-0.5S group; although no significant difference was observed with the control group (p < 0.01). The SiO2/Ag-1S, SiO2/Ag-0.5S, and SiO2/Ag-0.5NS groups exhibited higher microhardness after 30 d of immersion in water (p < 0.01). The surface roughness (Sa-µm) resembled that of the control at baseline, except for the SiO2/Ag-1NS group. For the baseline evaluation of flexural strength, all the experimental groups exhibited lower values than the control, except for SiO2/Ag-0.5NS and SiO2/Ag-0.5S, but after 30 d of immersion in water, there was no difference (p < 0.01). SIGNIFICANCE: The incorporation of 0.5% wt. of silanized nanofibers in the commercial composite (SiO2/Ag-0.5S) seemed to be promising, especially for its greater inhibition of S. mutans, adequate roughness, and flexural strength, in addition to high hardness, even after aging in water.

The effects of zoledronic acid on the progression of experimental periodontitis in rats: histological and microtomographic analyses.

PURPOSE: Periodontitis is considered a local risk factor for medication-related osteonecrosis of the jaws (MRONJ). However, little is known about the progression of periodontitis in the presence of zoledronic acid (ZOL). The aim of this study was to evaluate the effects of the systemic use of ZOL on the progression of experimental periodontitis (EP) in rats, as ZOL could modulate the progression of periodontitis and concomitantly cause MRONJ in individuals with periodontitis. METHODS: Forty-eight male Wistar rats were randomly distributed in 6 groups (n=8 each). To induce EP, ligatures were placed around the right first mandibular molars. Three groups were treated with ZOL (0.15 mg/kg/week, intraperitoneal), and 3 with 0.9% saline solution (controls). In the ZOL/Lig30 and ZOL/Lig 15 groups, after 4 weeks of treatment with ZOL, EP was induced and euthanasia was performed after 30 and 15 days of EP induction, respectively. In both groups, the animals continued to receive ZOL after EP until the end of the experiment. In the Lig/ZOL group, EP was induced first, and 15 days later, ZOL was administered for 8 weeks, with euthanasia 1 week after the last dose. After euthanasia, the mandibles were evaluated using micro-computed microtomography (micro-CT) and histomorphometry. Bone loss was measured, and the presence of osteonecrosis was evaluated histologically. The data were evaluated using the Student t-test and the Mann-Whitney test, with a significance level of 5%. RESULTS: In the Lig/ZOL group, micro-CT revealed less alveolar bone resorption in the distal root (P<0.01) than in the control group (Lig/Con). Histomorphometric analysis confirmed less alveolar bone resorption in the Lig/ZOL group (P=0.001). Histologically, osteonecrosis was more common in the ZOL groups. CONCLUSION: ZOL decreased alveolar bone resorption in rats with EP. However, it presented a higher risk for MRONJ.

Tobacco Use, Attitudes, Knowledge, and Perception About Smoking Cessation Counseling Among Brazilian Dental Students: a Cross-Sectional Study.

The aim of this study was to evaluate the prevalence of tobacco use, exposure to secondhand smoke, and knowledge and perception about smoking cessation counseling among dental students in Brazil. A cross-sectional study was performed at the School of Dentistry, Universidade Federal de Pernambuco, Brazil. The Global Health Professions Student Survey (GHPSS) research instrument was used. In the second half of 2017, students from the 5th to the 10th semester were recruited to answer the anonymous and self-administered survey in classrooms. The data were tabulated and analyzed, and information about the variables was presented using descriptive statistics. The association between the variables was determined through the Chi-square test and binary logistic regression. Two hundred and twenty-four students answered the survey. More than 40% of the students had tried cigarettes at least once and 8.9% were current smokers. About 28% of the participants reported having been exposed to secondhand smoke in their home and 57.1% in other environments. Most students recognized that they are role models for society and believed they should receive training in smoking cessation counseling. However, only 12.5% of the students reported having received some formal training in this subject. In conclusion, although dental students are aware of the harmful effects of tobacco, there is still a lack of training in smoking prevention and control among these future professionals.

Quality of information about oral cancer in Brazilian Portuguese available on Google, Youtube, and Instagram

BACKGROUND: To evaluate the quality of oral cancer information in Brazilian Portuguese on Google, YouTube, and Instagram. MATERIAL AND METHODS: The first 100 links of each platform characterized the initial sample. The websites and Instagram were evaluated using the JAMA benchmarks, the Discern instrument, and the Flesch readability index (Flesch Reading Ease). The existence of Health on the Net (HON) code was also registered on websites. The usefulness of each video on YouTube was classified as not useful, slightly useful, moderately useful, or very useful. RESULTS: Thirty-four websites, 39 Instagram posts, and 57 videos were evaluated, of which 18 (33.3%) websites and 19 (48.7%) Instagram posts covered only 2 of the 4 JAMA benchmarks. For the Discern instrument, 20 (37%) and 18 (33.3%) websites exhibited low and moderate reliability, respectively, while 26 (66.7%) Instagram posts were of low confidence. The level of intelligibility of both websites and Instagram was difficult. Only three websites exhibited the HONcode. Forty-one (71.9%) videos on YouTube were moderately useful. CONCLUSIONS: Information on oral cancer on the Internet in Brazilian Portuguese is of low quality. Thus, educational and governmental institutions have a responsibility to produce and indicate reliable sources of information for the population

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Positioning errors of dental implants and their associations with adjacent structures and anatomical variations: A CBCT-based study.

PURPOSE: The objective of the present study was to evaluate the prevalence of dental implants positioning errors and their associations with adjacent structures and anatomical variations by means of cone-beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT images of 207 patients (584 dental implants) were evaluated by 2 oral radiologists. The distance between the implant and the adjacent teeth/implants was measured and classified as adequate (≥1.5 mm and ≥3 mm, respectively) or inadequate. The presence of thread exposure, cortical perforation, implant dehiscence, implant penetration into adjacent structures, and anatomical variations was also recorded. The incisor canal diameter and the depth of the concavity of the submandibular fossa were measured in order to evaluate their correlations with the frequency of implant penetration in these structures. Descriptive analyses, the Fisher exact test, and Spearman correlation analysis were performed (α=0.05). RESULTS: The overall prevalence of positioning errors was 82.9%. The most common error was the inadequate distance between the implant and the adjacent teeth/implants. The presence of anatomical variations did not significantly influence the overall prevalence of errors (P>0.05). There was a positive correlation between the diameter of the incisor canal and the frequency of implant penetration in this structure (r=0.232, P<0.05). CONCLUSION: There was a high prevalence of dental implant positioning errors, and positioning errors were not associated with the presence of anatomical variations. Professionals should be aware of the space available for implant placement during the preoperative planning stage.

Knowledge and Attitudes of Primary Health Care Dentists Regarding Oral Cancer in Brazil.

OBJECTIVE: The aim of this study was to evaluate the knowledge and attitudes of dentists working in Primary Health Care Units from a Brazilian city, regarding oral cancer. MATERIALS AND METHODS: A prospective, cross-sectional, epidemiologic survey was performed. Seventy-one dentists from Primary Health Care Units were contacted at their workplace, and participated of the study. Data were collected through a self-administered questionnaire of 31 multiple-choice questions addressing the main clinical features and risk factors for oral cancer. The questionnaire was divided into two sections: questions related to general data and self-perception of the participants regarding personal knowledge of oral cancer, and objective questions related to general information on oral cancer (clinical features, characteristics, traits, and risk factors). The data were tabulated and analyzed by descriptive statistics. RESULTS: Participants were mostly females (81.5%), less than 40 years of age (57.7%), who underwent training 10-20 years ago (47.9%). Most respondents (66.2%) considered their level of knowledge about oral cancer to be satisfactory. However, only 26.8% of tem felt that they were able to carry out diagnostic procedures for oral cancer. Most of them (95.8%) were interested in participating in training courses on Oral Diagnostics; 56.3% of them reported not having received any training or guidance on how to conduct an examination to detect oral cancer during undergraduate training. CONCLUSIONS: These findings are consistent with previous reports and point to the need for new public policies to enable early diagnosis of oral cancer and a review of training in Oral Diagnostics in dental schools.

Myxoma of the mandibular condyle: Report of a rare case and review of the literature.

This report describes an extremely rare case of myxoma of the mandibular condyle. The tumor occurred in the left mandibular condyle of a 42-year-old woman, which was identified in a routine radiographic examination. The clinico-radiographic and histopathological features, and histogenesis of the lesion are discussed. A review of the literature and differential diagnosis of radiolucent condylar lesions are also presented.

Cemento-Osseous Dysplasias: Imaging Features Based on Cone Beam Computed Tomography Scans

Abstract Imaging exams have important role in diagnosis of cemento-osseous dysplasia (COD). Cone beam computed tomography (CBCT) stands out for allowing three-dimensional image evaluation. This study aimed to assess the prevalence of cases diagnosed as COD on CBCT scans, as well identify the main imaging features related to these lesions. An analysis was performed in a database containing 22,400 radiological reports, in which all cases showing some type of COD were initially selected. These CBCT exams were reevaluated to confirm the radiographic diagnosis and determine the prevalence and distribution of the types of COD with regard to gender, age and preferred location, while describing its most common imaging aspects. Data were presented using descriptive analyses. There were 82 cases diagnosed as COD in the CBCT images (prevalence of 0.4%). The distribution of patients was 11 (13.4%) male and 71 (86.6%) female, with a mean age of 49.8 years (age-range 17-85 years). There were 47 (57.3%) cases of periapical COD, 23 (28%) of focal COD and 12 (14.6%) of florid COD. The mandible was more affected than the maxilla. In most cases, the lesions were mixed or hyperdense. All COD had well-defined limits and there were no cases of tooth displacement. In conclusion, periapical COD was the most common type and the most affected bone was the mandible. Imaging evaluation is critical for diagnosis and dentists should bear in mind all possible radiographic presentations of COD in order to prevent misleading diagnoses and consequently, inadequate treatments.

Resumo Os exames por imagem têm papel importante no diagnóstico da displasia cemento-óssea (DCO). A tomografia computadorizada por feixe cônico (TCFC) se destaca por permitir a avaliação tridimensional da imagem. O objetivo neste estudo foi avaliar a prevalência de casos diagnosticados como DCO nos exames de TCFC, bem como identificar as principais características de imagem relacionadas a essas lesões. Uma análise foi realizada em um banco de dados contendo 22.400 laudos radiológicos, no qual todos os casos que apresentavam algum tipo de DCO foram inicialmente selecionados. Estes exames foram reavaliados para confirmar o diagnóstico radiográfico e determinar a prevalência e distribuição dos tipos de DCO em relação ao sexo, idade e localização preferencial, além de descrever seus aspectos imaginológicos mais comuns. Os dados foram apresentados por meio de análise descritiva. Oitenta e dois casos foram diagnosticados como DCO nas imagens de TCFC (prevalência de 0,4%). A distribuição dos pacientes foi de 11 (13,4%) homens e 71 (86,6%) mulheres, com idade média de 49,8 anos (faixa etária de 17 a 85 anos). Houve 47 (57,3%) casos de DCO periapical, 23 (28%) de DCO focal e 12 (14,6%) de DCO florida. A mandíbula foi mais afetada que a maxila. Na maioria dos casos, as lesões foram mistas ou hiperdensas. Todas as DCO apresentaram limites bem definidos e não houve casos de deslocamento dentário. Em conclusão, a DCO periapical foi o tipo mais comum e o osso mais afetado foi a mandíbula. A avaliação da imagem é crítica para o seu diagnóstico e os dentistas devem ter em mente todas as possíveis apresentações radiográficas da DCO, a fim de prevenir diagnósticos enganosos e, conseqüentemente, tratamentos inadequados.