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Age estimation methods through developmental atlases are simplified by image comparison using radiographs. Atlas-based methods have been utilized to create population-specific charts addressing population diversity. To tackle the absence of a dedicated atlas for the Brazilian population, the objective of the present study was to create a new atlas for dental development in Brazil based on the London Atlas chart. The new atlas (RP Atlas) is based on the median of tooth development, eruption, and resorption in individuals aged 5 to 23. The sample (567 individuals) was divided between females (n = 290) and males (n = 277). The RP Atlas was handcrafted, scanned, colored, and clustered in two atlases divided by sex. The development of a specific atlas for the Brazilian population has the potential to enhance the accuracy of age estimation in forensic scenarios, notably in a mixed country like Brazil. Further research is needed to assess the suitability of the newly developed atlas for the Brazilian population.

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Among the living tetrapods, mammals present a unique tooth replacement pattern, diphyodonty. Therefore, studying the dentition of mammalian ancestors is relevant to a better understanding of how this remarkable feature evolved. However, little is known about the postcanine tooth replacement pattern among Triassic cynodonts. Here, we applied the nondestructive method of microcomputed tomography (microCT) to analyze the dentition of the enigmatic Upper Triassic sectorial-toothed cynodont Charruodon tetracuspidatus (MCP 3934 PV, holotype) from the Candelaria Sequence, Santa Maria Supersequence, Brazil. The microCT-scan data allowed visualization of the replacement dentition and roots of the functional teeth, which provided information to inform interpretations of the ontogenetic stage and taxonomy of the species. A combination of dental and mandibular traits, as well as the small size of the specimen MCP 3934 PV, suggest an early ontogenetic stage. Additionally, the specimen could potentially be an ontogenetically immature form of another taxon, or a yet unknown species of probainognathian cynodont. Therefore, Charruodon tetracuspidatus is here designated as a nomen dubium, given the challenges of maintaining the species as valid.

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El trasplante dentario es una opción terapéutica para reemplazar un órgano dental perdido, causado por un proceso carioso extenso, agenesia, trauma-tismos o iatrogenias. Este procedimiento quirúrgico traslada un órgano dental íntegro desde un alveolo donante hacia su lecho receptor; para lo cual debe poseer ciertas características que permitan tener un pronóstico favorable a largo plazo. El presente estudio describe la evolución de un trasplante dental autólogo realizado hace 14 años a una paciente que acudió a la consulta para valoración del órgano den-tal 4.7, el que presentó un pronóstico desfavorable, por lo cual se realizó exodoncia y trasplante inme-diato del diente vital 4.8 al alveolo del órgano dental 4.7. Tras la planificación quirúrgica se procedió con la intervención conservando la vitalidad pulpar del diente a ser trasplantado, se realizó control clínico y radiográfico a los 15 días, 30 días, 6 meses, 1 año, 5 años y 14 años, en el que se observó conservación del paquete vasculonervioso y ligamento periodontal del órgano dental; a su vez se pudo evidenciar rizo-génesis en el diente trasplantado y un aumento de la altura del proceso alveolar, mediante mediciones realizadas en Auto CAD 2023 (AU)

Tooth transplantation is a therapeutic option to re-place a lost dental organ, caused by an extensive carious process, agenesis, trauma or iatrogenesis. This surgical procedure transfers a complete den-tal organ from a donor alveolus to its recipient bed; for which it must have certain characteristics that allow it to have a favorable long-term prognosis. The present study describes the evolution of an autolo-gous dental transplant carried out 14 years ago to a female patient who attended the consultation for evaluation of the dental organ 4.7, the same one that presented an unfavorable prognosis, for which an extraction and immediate transplantation of the 4.8 vital tooth was performed to the alveolus of the den-tal organ 4.7. After surgical planning, the intervention was carried out preserving the pulpal vitality of the tooth to be transplanted; clinical and radiographic control was performed at 15 days, 30 days, 6 months, 1 year, 5 years and 14 years, in which preservation of the vascular-nervous bundle and periodontal liga-ment of the dental organ was observed; in turn, rhizo-genesis in the transplanted tooth and an increase in the height of the alveolar process could be evidenced, through measurements made in Auto CAD 2023 (AU)

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El objetivo de este estudio fue comparar el tiempo empleado al estimar la edad dental (ED) entre el método propuesto por Demirjian et al. y el cuadro integral del enfoque de Demirjian (DAEcc) utilizando radiografías panorámicas digitales de individuos peruanos de 5 a 13 años residentes en Lima. Se realizó un estudio no experimental, comparativo, transversal y retrospectivo. Se utilizaron 100 radiografías panorámicas digitales que presentaban siete dientes permanentes mandibulares izquierdos. Una odontóloga forense capacitada y calibrada determinó el tiempo utilizado en evaluar la maduración dental y la estimación de ED con dos métodos (Demirjian y DAEcc). La unidad de medida utilizada fue los minutos (min.). No hubo diferencias en el tiempo de evaluación del estadio de maduración dental entre ambos métodos (p<0,05). El tiempo para estimar ED fue estadísticamente inferior con DAEcc (2,09 min) que con Demirjian (4,19 min). La diferencia del tiempo total de evaluación resultó estadísticamente significativa entre ambos métodos (Δ2,1 min.; 2,05-2,11; p=0,000). La aplicación del DAEcc redujo en 50 % el tiempo empleado en estimar ED en comparación con los cuadros propuestos por Demirjian. Aunque la odontología forense se centra en el estudio de la eficacia de estimación de la edad, es necesario abordar también su uso práctico.

SUMMARY: The objective of this study was to compare the time used to estimate dental age (DA) between the method proposed by Demirjian et al., and the comprehensive chart for dental age estimation (DAEcc) using digital panoramic radiographs of Peruvian individuals aged 5 to 13 years residing in Lima. A non- experimental, comparative, cross-sectional and retrospective study was carried out. 100 digital panoramic radiographs showing seven mandibular left permanent teeth were used. A trained and calibrated forensic odontologist determined the time used to assess tooth maturation and DA estimation with two methods (Demirjian and DAEcc). The unit of measurement used was minutes (min.). There were no differences in the evaluation time of the dental maturation stage between both methods (p<0.05). The time spent to estimate DA was statistically less with DAEcc (2.09 min) than with Demirjian (4.19 min). The difference in total evaluation time was statistically significant between both methods (Δ2.1 min; 2.05-2.11; p=0.000).The application of DAEcc reduced by 50 % the time spent estimating DA compared to the method proposed by Demirjian. Although forensic odontology focuses on the study of the effectiveness of age estimation, its practical use needs to be addressed as well.

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To apply Demirjian's seven (1973, D7) and four (1976, D4) teeth methods in a sample of Brazilian children and compare their performances for age estimation. Panoramic radiographs of 1200 children (600 females and 600 males) were collected from Southeast Brazil. The children were equally distributed (n = 60 females and 60 males) between age intervals of 1 year between 6 and 15.9 (mean age = 10.9; standard deviation [SD]: 2.9) years. D7 and D4 dental age estimation methods were applied by two observers and were compared based on their error rates (error = estimated age-chronological age). Both methods overestimated the chronological age (p < 0.0001). D7 led to overestimations of 0.71 (p < 0.0001) in females and 0.83 (p < 0.0001) in males, while the overestimations with D4 were 0.14 (p = 0.0067) and 0.73 (p < 0.0001) for females and males, respectively. The mean age estimated by D7 was 11.7 (SD: 3.1) years, while for D4, it was 11.3 (SD: 3.3) years. Intra- and interobserver agreement was ≥ 0.98. D4 optimized the performance of radiographic dental age estimation compared to D7. Improvements were reflected in the total sample and separately for female and male children from Southeast Brazil.

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Aim: To compare the accuracy of the panoramic radiography with cone-beam computed tomography (CBCT) scans in measuring the distances between root apexes and the adjacent anatomical structures including the maxillary sinus and the mandibular canal. Material and Methods: A total of 200 CBCT scans (100 maxillary and 100 mandibular) from patients who also had corresponding panoramic radiography were selected. Linear measurements (in mm) presenting centralized image were made between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus, and between the apexes of the mandibular teeth and the superior border of the mandibular canal by using specific software for panoramic radiography and the measurements on the coronal sections in CBCT scans. Data were submitted to inferential statistical analysis and Student's t-test for comparison between measurements. Results: CBCT scans were significantly more accurate than panoramic radiography to measure the distances between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus (p<0.05) and between the apexes of the mandibular teeth and the superior border of the mandibular canal or mental foramen (p<0.05). Conclusion: CBCT scans present more accurate measurements than panoramic radiography.

Objetivo: Comparar la precisión de la radiografía panorámica con las exploraciones de la tomografía computarizada dental de haz en cónico (CBCT) para medir las distancias entre los vértices radiculares y las estructuras anatómicas adyacentes, incluidos el seno maxilar y el canal mandibular. Material y Métodos: Se seleccionaron un total de 200 tomografías CBCT (100 maxilares y 100 mandibulares) de pacientes que además tenían la correspondiente radiografía panorámica. Se realizaron mediciones lineales (en mm) que presentaban imagen centralizada entre los ápices de los dientes maxilares y la pared inferior del seno maxilar, y entre los ápices de los dientes mandibulares y el borde superior del canal mandibular mediante software específico para radiografía panorámica. y las mediciones en las secciones coronales en escaneos CBCT. Los datos se sometieron a análisis estadístico inferencial y prueba t de Student para comparación entre mediciones. Resultados: Las exploraciones CBCT fueron significativamente más precisas que la radiografía panorámica para medir las distancias entre los ápices de los dientes maxilares y la pared inferior del seno maxilar (p<0,05) y entre los ápices de los dientes mandibulares y el borde superior de los dientes mandibulares. canal o agujero mentoniano (p<0.05). Conclusión: Las exploraciones CBCT presentan mediciones más precisas que la radiografía panorámica.

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INTRODUCTION: Autotransplantation is defined as the surgical movement or transposition of a tooth from its original site to a recipient alveolus, in the same patient. It has high success rates when performed within predefined parameters. OBJECTIVE: This study aims to describe the advantages of a dental autotransplantation protocol based on a multidisciplinary approach and using cone beam computed tomography, computer-aided planning, and rapid prototyping of the donor tooth, enabling the preparation of a surgical guide and postoperative protective plate. This article discusses the indications and contraindications for autotransplantation, as well as the selection criteria for the tooth to be transplanted and the transoperative care essential for its success. The parameters for post-operative control are described, in addition to the variables of success and failure to be considered. CONCLUSIONS: When analyzing the treatment options available for children with anterior tooth loss and the psychosocial impact on these patients, autotransplantation is considered not only an alternative treatment, but the only viable option for their functional, aesthetic, and social reestablishment.

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SUMMARY: This study aims to extract teeth and alveolar bone structures in CBCT images automatically, which is a key step in CBCT image analysis in the field of stomatology. In this study, semantic segmentation was used for automatic segmentation. Five marked classes of CBCT images were input for U-net neural network training. Tooth hard tissue (including enamel, dentin, and cementum), dental pulp cavity, cortical bone, cancellous bone, and other tissues were marked manually in each class. The output data were from different regions of interest. The network configuration and training parameters were optimized and adjusted according to the prediction effect. This method can be used to segment teeth and peripheral bone structures using CBCT. The time of the automatic segmentation process for each CBCT was less than 13 min. The Dice of the evaluation reference image was 98 %. The U-net model combined with the watershed method can effectively segment the teeth, pulp cavity, and cortical bone in CBCT images. It can provide morphological information for clinical treatment.

RESUMEN: El objetivo del presente estudio fue extraer estructuras dentarias y óseas alveolares desde imágenes CBCT automáticamente, lo cual es un paso clave en el análisis de imágenes CBCT en el campo de la estomatología. En este estudio, se utilizó la segmentación de tipo emántica para la segmentación automática. Se ingresaron cinco clases de imágenes CBCT marcadas, para el entrenamiento de la red neuronal U-net. El tejido duro del diente (incluidos esmalte, dentina y cemento), la cavidad de la pulpa dentaria, hueso cortical, hueso esponjoso y otros tejidos se marcaron manualmente en cada clase. Los datos se obtuvieron de diferentes regiones de interés. La configuración de la red y los parámetros de entrenamiento se optimizaron y ajustaron de acuerdo con un análisis predictivo. Este método se puede utilizar para segmentar dientes y estructuras óseas periféricas mediante CBCT. El tiempo del proceso de segmentación automática para cada CBCT fue menor a 13 min. El "Dice" de evaluación de la imagen de referencia fue de 98 %. El modelo U-net combinado con el método "watershed"puede segmentar eficazmente los dientes, la cavidad pulpar y el hueso cortical en imágenes CBCT. Puede proporcionar información morfológica para el tratamiento clínico.

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Objetivo: El objetivo del presente estudio fue analizar el grado de concordancia entre alumnos y docentes de dife- rentes unidades académicas en la evaluación radiográfica de tratamientos endodónticos realizados en dientes humanos "ex vivo". Materiales y métodos: Un docente y un alumno de grado pertenecientes a siete unidades académicas, dos cáte- dras de Endodoncia de Argentina y una de México, Ecuador, España, Chile y Portugal evaluaron radiográficamente 357 tratamientos endodónticos realizados "ex vivo" por estu- diantes de grado. De acuerdo con su criterio individual, de- terminaron si cada uno de esos tratamientos podía ser con- siderado como correcto o incorrecto. El coeficiente Kappa fue utilizado para el análisis estadístico. Resultados: El valor de Kappa fue entre 0,04 y 0,30 considerado como indicador de escasa concordancia y varió según la unidad académica en la que se habían registrado los datos. Conclusión: El nivel de concordancia en la categoriza- ción del resultado de la evaluación radiográfica de tratamien- tos endodónticos varía entre alumnos de grado y docentes de las distintas unidades académicas (AU)

Aim: To analyse the degree of agreement between stu- dents and teachers at different academic units regarding the radiographic evaluation of endodontic treatments performed on human teeth "ex vivo". Materials and methods: One teacher and one student from seven Academic units, two Departments of Endodontics in Argentina and one each in Mexico, Ecuador, Spain, Chile and Portugal conducted a radiographic evaluation of 357 endodontic treatments performed by undergraduate students. According to their individual criteria, they determined wheth- er the treatments were adequate or inadequate. Kappa coeffi- cient was used for statistical analysis. Results: The Kappa value was between 0.04 and 0.30, considered as an indicator of poor agreement, and varied ac- cording to the academic institution where the data had been recorded. Conclusion: The level of agreement in classifying the re- sults of the radiographic evaluation of endodontic treatments varies between undergraduate students and teachers at the different academic units (AU)

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Polyphyodonty-multiple tooth generations-in Mesozoic birds has been confirmed since the nineteenth century. Their dental cycle had been assessed through sparse data from tooth roots revealed through broken jawbones and disattached teeth. However, detailed descriptions of their tooth cycling are lacking, and the specifics of their replacement patterns remain largely unknown. Here we present unprecedented µCT data from three enantiornithine specimens from the Upper Cretaceous of southeastern Brazil. The high resolution µCT data show an alternating dental replacement pattern in the premaxillae, consistent with the widespread pattern amongst extinct and extant reptiles. The dentary also reveals dental replacement at different stages. These results strongly suggest that an alternating pattern was typical of enantiornithine birds. µCT data show that new teeth start lingually within the alveoli, resorb roots of functional teeth and migrate labially into their pulp cavities at an early stage, similar to modern crocodilians. Our results imply that the control mechanism for tooth cycling is conserved during the transition between non-avian reptiles and birds. These first 3D reconstructions of enantiornithine dental replacement demonstrate that 3D data are essential to understand the evolution and deep homology of archosaurian tooth cycling.

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