RESUMO
Introduction: Laser technology is gaining increasing importance in dental practice and also in the field of Endodontics with its ability to promote disinfection and experimentally in the preparation of root canal. The action of different types of lasers results in changes representing the increase in permeability of dentinal tissue (Er: YAG) or sometimes by a decrease in melting and recrystallization of dentin (Nd: YAG). Objective: this study assessed through apical dye leakage, the influence of irradiation with two types of laser, regarding to the quality of apical sealing of endodontic fillings. Material and methods: Thirty-six single-rooted teeth were used after being prepared with the ProFile system up to size #40 instrument and then divided into four experimental and two control groups. The technique used previously to the filling was as follows: G1 - not irradiated; G2 - irradiated with Er: YAG; G3 - irradiated with Nd: YAG and G4 - irradiated with Er: YAG followed by Nd: YAG. After external waterproofing and dry, the specimens were filled with a cold vertical condensation technique, using AH Plus sealer, and immediately immersed into 0.5% methylene blue solution for subsequent cleavage. The linear values of apical marginal leakage were obtained with the aid of an optical microscope connected to a computer using the Image Lab® software. Results: Data analysis showed the non-existence of statistically significant (p = 0.05) differences between different groups. Conclusion: It was concluded that the laser does not have influence on the apical sealing.
RESUMO
O preparo do canal radicular pode sofrer limitações, frente à situação anatômica de canais com curvaturas acentuados, promovendo desgastes e deformações dos instrumentos usados nesta fase cirúrgica. O objetivo deste estudo foi avaliar, comparativamente, a topografia da superfície do terço cervical e apical de quatro diferentes sistemas rotatórios antes e depois do uso por doze vezes, em blocos de resina com canais simulados padronizados com curvatura de 45° e analisados através da microscopia de força atômica - MFA e microscopia eletrônica de varredura - MEV. Foram utilizados 144 blocos de resina com canais simulados e curvatura padronizada. Os blocos foram divididos em quatro grupos e preparados segundo recomendação dos fabricantes pela técnica coroa-ápice: Grupo 1 - K3@; Grupo 2 - Protaper Universal@; Grupo 3 - Twisted Files@ e o Grupo 4 - Biorace@. A cada preparo, os instrumentos foram lavados e autoclavados. Foram selecionados 24 instrumentos sendo, 3 instrumentos novos e 3 após o 12° uso, de cada grupo. Estes instrumentos foram analisados na MFA (análise quantitativa) e MEV (análise qualitativa)...
Root canal preparation may suffer limitations facing the anatomical situation of accentuated curved root canais,. promoting wear and deformation of surgical instruments used at this stage. The aim of this study was to evaluate, comparatively, the topography of the cervical third and apical surfaces of four different rotatory systems before and after use by twelve times, in blocks of resin with standardized simulated canais with 45 o curvature and analyzed by Atomic Force Microscopy ¬AFM and Scanning Electron Microscopy - SEM. 144 resin blocks with simulated canais and standardized curvature were used. The blocks were divided into four groups and prepared according to manufacturers I recommendation by Crown-Apex technique: Group 1 - K3@; Group 2 - Protaper@ Universal; Group 3 - Twisted Files@ and Group 4 - Biorace@. After each canal preparation, the instruments were washed and autoclaved. 24 instruments were selected being, 3 new instruments and 3 after the 12th use, for each group. These instruments were analyzed through AFM (quantitative analysis) and SEM (qualitative analysis). In quantitative evaluation, it was used the average of the Rms (Root mean square) values of the four experimental groups, analyzed through the AFM technique, only the specimens of cervical third...
