Microtomographic Evaluation of Canal Centralization and Dentine Removal after Canal Preparation with Two Rotary Systems: HyFlex EDM and ProTaper Next.

OBJECTIVE: This study compared the ProTaper Next (PTN; Dentsply Sirona, Tulsa, Oklahoma, United States) and HyFlex EDM (HEDM; Coltene/Whaledent AG, Alstätten, Switzerland) systems using micro-computed tomography (CT). MATERIALS AND METHODS: Twenty-one mesial roots classified as Vertucci's type IV from extracted mandibular first molars with curvatures between 20 and 40 degrees were selected. The teeth were scanned using a micro-CT before and after root canal preparation by both systems, applied to the same root, in alternating canals. The following parameters were analyzed: canal centering, apical transportation, root canal diameter/root diameter. RESULTS: No statistically significant differences between both systems were observed for any of the assessed morphological parameters (p > 0.05). All canals presented diameter enlargement of more than 40% in relation to root diameter in the cervical and middle segments. No statistically significant difference was noted between the HEDM and PTN groups. The wear percentage for the HEDM group in the cervical and middle thirds were 49.66 ± 8.65 and 46.48 ± 14.29, respectively, and 51.02 ± 11.81 and 45.48 ± 10.79 for the PTN group, respectively. CONCLUSION: Both systems displayed similar mandibular molar mesial canals preparation, with no differences noted for any of the assessed parameters. Both groups showed increased canal diameter in the cervical and middle thirds by more than 40%.

Análise da cor dos dentes naturais em pacientes idosos / Natural teeth color in older patients

Este estudo teve como objetivo avaliar o comportamento do método da cor da pele, bem como os principais grupos de cores dos dentes naturais entre 126 pacientes dentados com idade variando de 50 a 70 anos. Os resultados do trabalho mostraram que houve uma baixa coincidência entre o método da cor da pele e os indivíduos estudados (45,1 por cento) e que a grande maioria dos pacientes teve uma tendência para as cores claras e médias de dentes naturais, sendo que o grupo feminino mostrou uma incidência maior de cores claras (54 por cento, considerando o incisivi central). Outra conclusäo foi que nos pacientes com faixa etária mais avançada houve um aumento para os grupos de cores médias e escuras para os dentes naturais