Nd:YAG laser irradiation effect on apical intracanal dentin - a microleakage and SEM evaluation.
The purpose of this in vitro study was to evaluate the effect of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser irradiation on intracanal dentin surface by SEM analysis and its interference in the apical seal of filled canals. After endodontic treatment procedures, 34 maxillary human incisors were randomly assigned to 2 groups. In the negative control group (n=17), no additional treatment was performed and teeth were filled with vertically condensed gutta-percha; in the laser-treated group (n=17), the root canals were irradiated with Nd:YAG laser (1.5 W, 100 mJ, 15 Hz) before filling as described for the control group. Two specimens of each group were prepared for SEM analysis to evaluate the presence and extent of morphological changes and removal of debris; the other specimens were immersed in 0.5% methylene blue dye (pH 7.2) for 24 h for evaluation of the linear dye leakage at the apical third. SEM analysis of the laser-treated group showed dentin fusion and resolidification without smear layer or debris. The Student's t-test showed that the laser-treated group had significantly less leakage in apical third than the control group. Within the limitations of this study, it may be concluded that the morphological changes on the apical intraradicular dentin surface caused by Nd:YAG laser resulted in less linear dye apical leakage.
Department of Endodontics, Dental School, University of São Paulo, Brazil. caciomn@usp.br
Cacio
C
Moura-Netto
Camila de A B
Cde A
Guglielmi
Anna Carolina Volpi
AC
Mello-Moura
Renato Miotto
RM
Palo
Daniela Prócida
DP
Raggio
Celso Luiz
CL
Caldeira
D004396:Coloring Agents; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification*; D003786:Dental Pulp Cavity / Q000528:radiation effects* / Q000648:ultrastructure; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure; D004853:Epoxy Resins / Q000737:chemistry / Q000627:therapeutic use; D006171:Gutta-Percha / Q000737:chemistry / Q000627:therapeutic use; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008422:Materials Testing; D008751:Methylene Blue; D008855:Microscopy, Electron, Scanning; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012389:Root Canal Obturation / Q000379:methods; D018915:Root Canal Preparation / Q000379:methods; D016369:Smear Layer; D013997:Time Factors; D019227:Tooth Apex / Q000528:radiation effects* / Q000648:ultrastructure
D004396:Coloring Agents; D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C534916:epoxy resin-based root canal sealer; D006171:Gutta-Percha; D008751:Methylene Blue