Accuracy of Dental Calcification Stages in Predicting the Peak Pubertal Stage of Females.

Objective: This study aimed to evaluate the accuracy of dental calcification stages in predicting the peak pubertal stage. Methods: This retrospective study was conducted on panoramic and lateral cephalometric images of 406 female patients aged 9-14 years. The skeletal maturity and calcification stages of the mandibular canines, first premolars, second premolars, and second molars were determined using the Hassel-Farman and Demirjian (DI) methods, respectively. The prediction accuracy of the peak pubertal stage with the studied teeth was assessed using a receiver operating characteristic curve and the area under the curve (AUC). The DI stage of H was designated as the reference level, and Bayesian logistic regression analysis was used to assess the coinciding chance of each DI stage and peak pubertal stage. Results: The AUC range of studied teeth was 0.84-0.92 in predicting peak pubertal stage (all p<0.001). In the canines and first premolars, the coinciding chance of peak pubertal stage and stage H was significantly higher than that in other stages [p<0.05, odds ratio (OR) ≤0.14]. In the second premolars and second molars, the chance of peak pubertal stage coinciding with stages H and G did not significantly differ (p>0.05); however, the chance of stage G coinciding with peak pubertal stage in the second molars was higher than in stage H (OR=4.59). Conclusion: Stage H in all studied teeth and stage G in the second premolars and second molars predict peak pubertal stage with high accuracy. Considering that stage H is the end of tooth calcification stages and the accuracy of predicting stage G of second molar teeth is higher than the above stage, estimating the peak pubertal stage is recommended by the second case.

Volumetric Evaluation of Maxillary Lateral Incisor Root Resorption due to Positional Variations of Impacted Canine.

Introduction: The purpose of this study was to investigate the relationship of the volume of lateral incisor resorption and impacted canine features. Materials and Methods: This study consisted of CBCT images of 47 samples with unilateral impacted maxillary canine (13 males and 34 females). The volume of lateral incisors in impacted side and nonimpacted side was calculated with the Mimics 10.01 software. Canine and lateral incisor angulations were measured in panoramic reformatted images. The canine cusp tip distance from midpalatal suture was measured in axial cross-section images. Results: The difference between two sides volume was considered as the mean volume of resorption (MVR) that was statistically significant (P < 0.001). MVR was not statistically significant between two sexes (P=0.95), in buccopalatal and mesiodistal positions of impacted canine, and in different angulations or distances of the impacted canine to midline (P > 0.05). The concurrent effect of the canine distance to the midline and the angle of the canine with the lateral incisor on the MVR were statistically significant (P=0.049). Conclusion: The maximum rate of lateral root resorption is when the distance from the canine to the midline is less than 5 mm and the angle of the canine to the lateral incisor is 30-60 degrees.

Age estimation by pulp/tooth area and width ratios in panoramic images of upper and lower canines among the Iranian population / Estimativa da idade por área de polpa/dente e relações de largura em imagens panorâmicas de caninos superiores e inferiores entre a população iraniana

Objective: One of the techniques of estimating age in forensic medicine, which is associated with the least trauma in both living individuals and corpses, is to use teeth. Accordingly, the present study aims to determine the relationship between chronological age and pulp-to-tooth area ratio and pulp-to-root width ratio in maxillary and mandibular canines on panoramic radiographs among the Iranian population. Material and Methods: A total of 162 panoramic radiographs were evaluated in the present study. Selected patients were of verified age with the age range of 15-45 years. The pulp-to-tooth area ratio (PTR) and the pulp-to-root width ratio were calculated with AutoCAD 2016 software program in maxillary and mandibular canines at two points of the root. The two points include cemento-enamel Junction (CEJ) and pulp/root width at the quarter of a distance between CEJ and end point of root-canal, which was named WA, WB respectively. The patients' age was also estimated with the use of linear regression equation. Then each patient's chronological age and the age estimated using this technique was compared. Results: The relationship between PTR in both canines and WB variable in maxilla with chronological age was inverse and significant (P < 0.05); However, there was no strong correlation coefficient (r≤- o.37). Gender had no effect on the results of the study. The mean difference between predicted age and actual age with combined PTR and WB formula was lower than 1 year. When the mean of PTR or WB variables was considered as a predictor, significant results were obtained (P < 0.05), showing a decrease in Standard error of estimation (SEE). The results were not significant when variables of upper PTR and lower PTR and the interaction between them were included in the linear regression model (p > 0.05). Same results were obtained with the variable of WB. Conclusion: Combining the variables of PTR and WB gives better results than using variables alone. Estimation of age with the mean of each variable shows less error than their combination. (AU)

Objetivo: Uma das técnicas de estimativa da idade na medicina legal, que está associada ao menor trauma em indivíduos vivos e cadáveres, é usar os dentes. Nesse sentido, o presente estudo tem como objetivo determinar a relação entre a idade cronológica e a relação área polpa-dente e relação largura-polpa-raiz em caninos superiores e inferiores em radiografias panorâmicas na população iraniana. Material e Métodos: Um total de 162 radiografias panorâmicas são avaliadas no presente estudo. Os pacientes selecionados são da idade verificada com a faixa etária de 15-45 anos. A relação de área polpa-dente (PTR) e a relação largura-polpa-raiz são calculadas com o programa de software AutoCAD 2016 em caninos superiores e inferiores em dois pontos da raiz. Os dois pontos incluem a junção cemento-esmalte (CEJ) e a largura da polpa / raiz no quarto de distância entre a CEJ e o ponto final do canal radicular, que é denominado WA, WB. A idade dos pacientes também é estimada com o uso da equação de regressão linear. Em seguida, a idade cronológica de cada paciente e a idade estimada usando esta técnica são comparadas. Resultados: A relação entre a PTR em ambos os caninos e a variável WB na maxila com a idade cronológica é inversa e significativa (P <0,05); No entanto, não existe um coeficiente de correlação forte (r≤- o.37). O gênero não tem efeito nos resultados do estudo. A diferença média entre a idade prevista e a idade real com a combinação de PTR e fórmula WB é inferior a 1 ano. Quando a média das variáveis PTR ou WB é considerada como preditora, resultados significativos são obtidos (P <0,05), mostrando uma diminuição no SEE. Os resultados não são significativos quando as variáveis de PTR superior e PTR inferior e a interação entre elas são incluídas no modelo de regressão linear p> 0,05). Os mesmos resultados são obtidos com a variável de WB. Conclusão: Combinar as variáveis de PTR e WB dá melhores resultados do que usar variáveis sozinhas. A estimativa da idade com a média de cada variável apresenta menos erros do que sua combinação. (AU)

In vitro comparison of two photostimulable phosphor plate systems for early detection of occlusal dentin caries with and without a sharpening filter.

Background. Dental caries is the most important reason for tooth loss. Clinical examination is the most commonly used technique for occlusal caries diagnosis. The diagnostic power of digital systems is a matter of controversy in this field. The present study aimed to determine the diagnostic accuracy of two photostimulable phosphor plate (PSP) systems for early occlusal dentin caries in vitro. Methods. Sixty-nine extracted molar and premolar teeth were used in this study. The teeth were mounted in triple blocks, and standard radiographs were taken by the Digora and Acteon digital radiographic systems. The original and filter 1-enhanced radiographs were evaluated by two experienced observers twice at an interval of two weeks, and dentin caries was recorded in Tables prepared for the study. The teeth were then sectioned in a buccolingual direction and evaluated under a stereomicroscope. The observers' reports were compared with microscopic findings as the gold standard. SPSS 23 was used to calculate the kappa coefficient, sensitivity, specificity, and area under the ROC curve (AUC). Statistical significance was set at P<0.05. Results. The internal and the external agreements in both imaging systems were good to excellent. The means of sensitivity, specificity, and AUC in the Acteon system were 34.1, 92.9, and 0.674, with 30.8, 94.8, and 0.659, respectively, in the Digora system. Conclusion. The accuracy of early occlusal caries diagnosis was poor on both systems, and no significant difference was observed between the two systems at a 95% confidence interval. Although the AUC was slightly higher in the original images, there was no significant difference between them; however, due to their high specificity, they can prevent unnecessary treatments in the clinic.

Accuracy of Cone Beam Computed Tomography, Photostimulable Phosphor Plate Digital Radiography and Conventional Radiography for Detection of Artificial Cancellous Bone Defects.

OBJECTIVES: The optimal goal of radiography is to provide high-quality diagnostic images with the least patient radiation dose. The aim of this study was to evaluate the accuracy of cone-beam computed tomography (CBCT) and intraoral photostimulable phosphor plate (PSP) digital and film-based conventional radiography for detection of artificial cancellous bone defects. MATERIALS AND METHODS: Five dry human mandibles were used in this study. The mandibles were placed inside a water bath made of plexiglass plates; then PSP and CBCT scans were obtained. The mandibles were cut by a coping saw in buccolingual dimension and oval defects measuring 6.1×6.1 mm, 3×6.1 mm and 4×4 mm were created by a milling machine in the spongy bone. After fixing the two parts together (buccal and lingual), radiographs were repeated. Presence or absence of defects on images was evaluated and recorded by the two observers. Using SPSS 16, compatibility level, sensitivity, specificity and receiver operating curve (ROC) analysis were determined for each observer. RESULTS: The intraobserver agreement in all three imaging modalities was low to moderate (kappa≤0.613). The inter-observer agreement in all the three imaging modalities was moderate (kappa=0.406). The area under the curve (AUC) of the imaging modalities in each observation was not significantly different. The area under the curve based on defect size for the two observers was not significantly different either. CONCLUSION: Defects confined to spongy bone can be identified on film and PSP radiographs and CBCT scans. However, interpretation of PSP images and CBCT scans needs greater expertise and skills.