Evaluation of two methods of tracings for implants in panoramic radiographs

In the last years, computer programs have appeared in order to help dental practitioners in implants planning. These programs aim to facilitate the acquisition of adequate measures in digitalized radiographs. The aims of this study were: to evaluate the intra-examiner agreement in the acquisition of measures using two methods (manual and computer program - Radioimp), comparing their performances. Three examiners analyzed twenty-one panoramic radiographs. They used the two methods in two occasions. In the manual method, the examiners made a tracing on a paper fixed to the images and measured nine regions with a caliper. The images were digitalized and showed in a computer screen to be analyzed in the computer program. The examiners acquired measures of the same regions by the manual method. Vertical measures of spheres in the images were acquired in order to discount the magnifying factor of the technique. Through statistics analysis (p=.05), it was possible to conclude that there were differences in intra-examiner agreement and the examiners had greater difficulty in reproducing the measures when they used the computer program; the measures acquired by the manual method were closer to the real ones.Nos últimos anos, surgiram, na Odontologia, programas de computador para auxiliar o profissional no planejamento de implantes. Esses programas visam facilitar a obtenção de medidas adequadas em exames radiográficos digitalizados. Os objetivos desse trabalho foram: avaliar a concordância intra-examinador na obtenção de medidas por dois métodos (o manual e o com um programa de computador - Radioimp); e comparar o desempenho dos dois métodos. Para isso, 21 radiografias panorâmicas foram analisadas por três avaliadores, pelos dois métodos, em duas ocasiões. No método manual, os avaliadores realizaram um traçado sobre papel acetato fixado às imagens, e, com um paquímetro, obtiveram medidas de nove regiões. Para a análise das imagens no programa de computador, essas foram digitalizadas e exibidas em uma tela de computador. Os avaliadores obtiveram medidas das mesmas regiões analisadas pelo método manual. Para desconto da ampliação inerente à técnica, foram obtidas medidas verticais de esferas presentes nas imagens. Os resultados foram submetidos à análise estatística (p=0.05). Houve diferenças entre os avaliadores na concordância intra-examinador, sendo que esses apresentaram maior dificuldade na reprodução das medidas, quando utilizaram o programa de computador; a maioria das medidas que apresentaram falta de exatidão foi obtida ao se utilizar o mesmo programa. Dessa forma, os programas destinados ao planejamento de implantes devem ser utilizados com cautela por pessoas treinadas

Comparison of automatic and visual methods used for image segmentation in Endodontics: a microCT study

To calculate root canal volume and surface area in microCT images, an image segmentation by selecting threshold values is required, which can be determined by visual or automatic methods. Visual determination is influenced by the operator's visual acuity, while the automatic method is done entirely by computer algorithms. Objective: To compare between visual and automatic segmentation, and to determine the influence of the operator's visual acuity on the reproducibility of root canal volume and area measurements. Material and methods: Images from 31 extracted human anterior teeth were scanned with a μCT scanner. Three experienced examiners performed visual image segmentation, and threshold values were recorded. Automatic segmentation was done using the “Automatic Threshold Tool” available in the dedicated software provided by the scanner's manufacturer. Volume and area measurements were performed using the threshold values determined both visually and automatically. Results: The paired Student's t-test showed no significant difference between visual and automatic segmentation methods regarding root canal volume measurements (p=0.93) and root canal surface (p=0.79). Conclusion: Although visual and automatic segmentation methods can be used to determine the threshold and calculate root canal volume and surface, the automatic method may be the most suitable for ensuring the reproducibility of threshold determination

Reprodutibilidade diagnóstica do alongamento do processo estilóide

The aim of this study was to estimate the reproducibility related to the presence and to the measurements of elongated styloid process (ESP), based on panoramic radiographs and the prevalence of ESP. Experimental design: one hundred sixty six panoramic radiographs were used, from edentulous patients from the Radiology Clinic files, at Araraquara Dental School, Unesp, during a four-year period. One hundred and twenty one were female and 45 were male. Two calibrated observers evaluated the radiographs. A caliper was used to measure, in mm, the ESP from the base of the temporal bone to the tip of the structure. The ESP was considered present when the measurements were 30mm or more. Kappa statistics (k ) and intra-class correlation coefficient (r ), were applied to estimate the reproducibility. The results showed that related to the presence of ESP, the interobserver agreement was k =0.85. Related to the measurements of ESP, the interobserver agreement was r =0.52. The prevalence of ESP was estimated in 12.6%. ESP distribution in females was similar to that for males. In conclusion, we found a greater level of agreement when observers evaluated the presence of ESP than when they did the measurement of ESP. The prevalence of ESP was 12.6%.O objetivo deste trabalho foi avaliar a reprodutibilidade relacionada à presença e às medidas do alongamento e a prevalência do processo estilóide (APE), utilizando radiografias panorâmicas. Foram utilizadas cento e sessenta e seis radiografias, do arquivo da Clínica de Radiologia, da Faculdade de Odontologia de Araraquara, Unesp, de pacientes desdentados, atendidos num período de quatro anos. Cento e vinte um pacientes eram do gênero feminino e quarenta e cinco do masculino. Dois examinadores calibrados avaliaram as radiografias. Foi utilizado um paquímetro para medir, em mm, o APE da base do osso temporal à extremidade da estrutura. O APE foi considerado presente quando as medidas ultrapassaram 30 mm. A reprodutibilidade foi avaliada utilizando a estatística Kappa (ê) e o coeficiente de correlação intra-classe (ñ). Os resultados mostraram que a concordância interexaminador foi ê=0,85, relativa à presença do APE e ñ=0,52 relativa às medidas do APE. A prevalência do APE foi 12,6%. A distribuição do APE no gênero feminino foi semelhante ao masculino. Concluindo, o nível de concordância entre os dois examinadores quanto à presença do APE foi maior do que quando eles mediram o APE. A prevalência do APE foi 12,6%

Prevalence of C-shaped root canal in a Brazilian subpopulation: a cone-beam computed tomography analysis

The aim of this study was to use cone-beam computed tomography (CBCT) images to evaluate the prevalence and configurations of C-shaped canals in permanent mandibular second molars among members of a Brazilian subpopulation. CBCT exams of 214 patients (406 teeth) were evaluated for: presence of C-shaped root canals, number of canals and direction of the root grooves (buccal or lingual). Of the 214 CBCT images examined, 192 showed intact bilateral molars, which were used to analyze the distribution of unilateral and bilateral occurrences of C-shaped canals. The prevalence of these canals was correlated with gender and age, and the number of canals was correlated with the direction of the root grooves using the chi-squared test (α = 0.05). The prevalence of C-shaped canals was 15.3%. This prevalence did not differ with gender or age. Most of the C-shaped molars had three (43.5%) or two (37.1%) canals; 69.4% of the C-shaped canals were grooved in the buccal direction; 68.3% of the C-shaped cases were unilateral. In conclusion, there was a significant prevalence of C-shaped canals in the mandibular second molars of the population studied; the C-shaped canal system varied in configuration, with a higher prevalence of three and two canals and unilateral occurrence; CBCT is a useful tool for endodontic diagnosis and treatment.The aim of this study was to use cone-beam computed tomography (CBCT) images to evaluate the prevalence and configurations of C-shaped canals in permanent mandibular second molars among members of a Brazilian subpopulation. CBCT exams of 214 patients (406 teeth) were evaluated for: presence of C-shaped root canals, number of canals and direction of the root grooves (buccal or lingual). Of the 214 CBCT images examined, 192 showed intact bilateral molars, which were used to analyze the distribution of unilateral and bilateral occurrences of C-shaped canals. The prevalence of these canals was correlated with gender and age, and the number of canals was correlated with the direction of the root grooves using the chi-squared test (α = 0.05). The prevalence of C-shaped canals was 15.3%. This prevalence did not differ with gender or age. Most of the C-shaped molars had three (43.5%) or two (37.1%) canals; 69.4% of the C-shaped canals were grooved in the buccal direction; 68.3% of the C-shaped cases were unilateral. In conclusion, there was a significant prevalence of C-shaped canals in the mandibular second molars of the population studied; the C-shaped canal system varied in configuration, with a higher prevalence of three and two canals and unilateral occurrence; CBCT is a useful tool for endodontic diagnosis and treatment281394

CBCT post-processing tools to manage the progression of invasive cervical resorption: a case report

This case report aimed to highlight the usefulness of cone beam computed tomography (CBCT) and its post-processing tools for the diagnosis, follow-up and treatment planning of invasive cervical resorption (ICR). A 16-year-old female patient was referred for periapical radiographic examination, which revealed an irregular but well demarcated radiolucency in the mandibular right central incisor. In addition, CBCT scanning was performed to distinguish between ICR and internal root resorption. After the diagnosis of ICR, the patient was advised to return shortly but did so only six years later. At that time, another CBCT scan was performed and CBCT registration and subtraction were done to document lesion progress. These imaging tools were able to show lesion progress and extent clearly and were fundamental for differential diagnosis and treatment decision.This case report aimed to highlight the usefulness of cone beam computed tomography (CBCT) and its post-processing tools for the diagnosis, follow-up and treatment planning of invasive cervical resorption (ICR). A 16-year-old female patient was referred f274476480sem informaçãosem informaçãoCom este relato de caso clínico objetiva-se enfatizar a contribuição das ferramentas de pós-processamento aplicadas às imagens de tomografia computadorizada de feixe cônico (TCFC) no diagnóstico, acompanhamento e decisão do tratamento de reabsorção cervi

More frequent detection of calcified carotid atherosclerotic plaques and mineralized laryngeal cartilages on digital than on film-based panoramic radiographs

To determine whether calcified carotid atherosclerotic plaques (CCAPs) and mineralized laryngeal cartilages (MLCs) were more frequently detected on digital or film-based panoramic radiographs. The clinical relevance of this question is that some radiopacities seen on digital radiographs may correspond to medium-density tissues that are not necessarily mineralized. Materials and Methods: Data were collected from panoramic radiographs and the respective reports issued by 2 private oral radiology centers. A total of 388 radiographs and reports were divided into film-based (group A) and digital (group D) radiographs. The frequencies of CCAPs and MLCs were analyzed using the Fisher exact test, and odds ratios were also calculated (alpha = 1%). Results: The mean age of patients whose reports and radiographs showed CCAPs and/or MLCs ranged from 50.1 to 54.1 years. There was a predominance of females. A higher frequency of CCAPs and MLCs was observed in group D than in group A at both centers (P < 0.01). CCAPs and MLCs were detected 4 times more frequently in group D than in group A at one of the centers. Conclusion: CCAPs and MLCs were more frequently detected on digital than on film-based panoramic radiographs. Further studies are needed to determine whether such radiopacities do indeed correspond to mineralized, rather than medium-density, tissues4916570sem informaçãosem informaçã

Accuracy of ITK-SNAP software for 3D analysis of a non-regular topography structure

To evaluate the accuracy of ITK-SNAP software for measuring volumes of a non-regular shape structure, using cone beam computed tomography (CBCT) scans, besides for developing a mathematical model to correct the software measurement error in case it existed. A phantom made by moulding a rubber duck’s head was filled with total (38,000 mm3) and partial volumes of water (7000 mm3, 14,000 mm3, 21,000 mm3, 28,000 mm3 and 35,000 mm3), which constituted the gold standards. The sound phantom and the phantom filled with different volumes of water were scanned in a Picasso Trio CBCT unit set at 80 kVp, 3.7 mA, 0.2 mm3 voxel and 12 × 8.5 cm field of view. Semi-automatic segmentation was performed with ITK-SNAP 3.0 software by two trained oral radiologists. Linear regression analyzed the relation between ITK-SNAP calculated volumes and the gold standard. Intraclass correlation coefficient was applied to analyze the reproducibility of the method. Significance level was set at 5%. Linear regression analysis showed a significant relationship between ITK-SNAP volumes and the gold standard (F = 22,537.3, p < 0.0001), with an R2 of 0.9993. The average error found was 4.7 (± 4.3) %. To minimize this error, a mathematical model was developed and provided a reduction of it. ICC revealed excellent intra-examiner agreements for both examiners 1 (ICC = 0.9991, p < 0.0001) and 2 (ICC = 0.9989, p < 0.0001). Likewise, inter-examiner agreement was excellent (ICC = 0.9991, p < 0.0001). The software showed to be accurate for evaluating non-regular shape structures. The mathematical model developed reduced an already small error on the software’s measurements36183189COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES00

Intra-sinusal third molar: Case report

Ectopic tooth eruption into an area other than the oral cavity is rare. Nasal septum, mandibular condyle, coronoid process and infratemporal fossa space have been reported as frequent locations for ectopic tooth eruption. Ectopic teeth located within the maxillary sinus may be asymptomatic, found only in routine examinations. Headache, sinusitis and nasal obstruction are some of the associated symptoms. The differential diagnosis includes foreign bodies (rhinolith), infections (syphilis and tuberculosis), benign lesions (hemangioma, osteoma, calcified polyp) and malign lesions (osteosarcoma). Upper third molars located within the maxillary sinus may be associated with the development of mucocele or dentigerous cyst. The aim of this paper was to describe the case of a 24-year old female patient with an ectopic right upper third molar in the maxillary sinus. A hyperdense area was observed with sinus obliteration, consistent with mucous material

Estimativa do sexo em Tomografias Computadorizadas da região sudeste brasileira / Gender estimation in Computerized Tomography of the brazilian southeast region

Verificar a presença de dimorfismo sexual por meio de medidas lineares de TCs cranianas, bem como, a criação de um modelo matemático para estimativa do sexo. Foram utilizados 200 Tomografias Computadorizadas (TCs) do Biobanco Osteológico e Tomográfico da região sudeste brasileira. Para a pesquisa foram realizadas seis medidas lineares (Porção anterior da sela turca a sutura naso-frontal, Porção anterior da sela turca ao bregma, Forame incisivo ao ponto básio, Porção anterior da sela turca a meato acústico externo (direito), Porção anterior da sela turca a meato acústico externo (esquerdo) e Porção anterior da sela turca a meato acústico externo (esquerdo) a porção anterior da sela turca a meato acústico externo (direito), utilizando o software OnDemand3D ™. Para a calibração foi utilizado o teste estatístico ICC, segundo Szklo e Nieto (2000) obtendo-se correlação FORTE e a análise dos dados foi utilizado o teste de Kolmogorov-Smirnov, teste t, Teste de Shapiro-Wilke e Levene e uma regressão logística pelo método de Stepwise-Forward (Wald), para analisar a distribuição e igualdade das variâncias. Foi constatado dimorfismo sexual em todas as medidas realizadas. Sendo possível criar um modelo de regressão logística [Logito= -41.7732 + 0.2636*PAST-SFN + 0.0601*PAST-B], onde foi obtido o valor de sensibilidade (80.2%), especificidade (70.2%) e uma acurácia de (76%). Conclui-se que o modelo obtido de regressão logística possibilita a estimativa do sexo de brasileiros, podendo ser utilizado como uma metodologia auxiliar no processo de identificação humana