Influence of laser irradiation on fiber post retention.
The purpose of this in vitro study was to compare the bond strength between fiber post and laser-treated root canals. Forty single-rooted bovine teeth were endodontically treated and randomly divided into four groups of equal size according to the root canal treatment: group 1 conventional treatment (without laser irradiation); group 2 Nd:YAG laser (1.5 W, 10 Hz, 100 mJ); group 3 Er,Cr:YSGG laser (0.75 W, 20 Hz); and group 4 Nd:YAG + Er,Cr:YSGG lasers. The fiber posts were cemented with an adhesive system + resin cement, in accordance with the manufacturer's instructions. A mini acrylic pipe was fixed on the coronal section of the post using a light-polymerized resin. Specimens were mounted on an acrylic pipe with a self-polymerized resin. Retention forces were determined using a universal testing machine (0.5 mm/min). Data were analyzed using one-way ANOVA and Tukey tests (p <0.05). The post retention force in group 2 was found to be lower than that in the other experimental groups. Fractures were observed at the interface between the dentin and the resin in all groups. High-intensity lasers can be used in conventional endodontic treatment; however, root canal surface irradiation using the Nd:YAG laser was shown to negatively affect the post retention force.
Department of Restorative Dentistry, University of São Paulo, São Paulo, SP, Brazil. dynagase@usp.br
Denis Y
DY
Nagase
Patricia M
PM
de Freitas
Susana
S
Morimoto
Margareth
M
Oda
Glauco F
GF
Vieira
D000818:Animals; D002417:Cattle; D001840:Dental Bonding; D003786:Dental Pulp Cavity / Q000528:radiation effects / Q000601:surgery; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents; D053844:Lasers, Solid-State / Q000009:adverse effects*; D011176:Post and Core Technique; D012390:Root Canal Therapy / Q000009:adverse effects*
D017220:Dentin-Bonding Agents