UV irradiation improves the bond strength of resin cement to fiber posts

Abstract

The purpose is to evaluate the effect of UV irradiation on the bond strength between epoxy-based glass fiber posts and resin cement. Twelve epoxy-based glass fiber posts were randomly divided into three groups. Group 1 (Cont.): No surface treatment. Group 2 (Low-UV): UV irradiation was conducted from a distance of 10 cm for 10 min. Group 3 (High-UV): UV irradiation was conducted from a distance of 1 cm for 3 min. A resin cement (CLEARFIL SA LUTING) was used for the post cementation to form resin slabs which contained fiber posts in the center. Microtensile bond strengths were tested and the mean bond strengths (MPa) were 18.81 for Cont. group, 23.65 for Low-UV group, 34.75 for High-UV group. UV irradiation had a significant effect on the bond strength (p<0.05). UV irradiation demonstrates its capability to improve the bond strength between epoxy-based glass fiber posts and resin cement.

Effect of ultraviolet light irradiation period on bond strengths between fiber-reinforced composite post and core build-up composite resin

“…The UV irradiation wavelength in the present study was similar to that in the previous study by Zhong et al 14) , but the distance between the UV lamp and FRC post, and the period of UV irradiation were different. Therefore, the bond strengths measured from 0 to 600 s in the present study might clarify the effects of the UV irradiation period.…”

“…Improving the bond strength by UV irradiation was discussed based on the amount of UV irradiated energy on the FRC post surface 14) . The irradiated surface energy (E) on the post surface is calculated as the function of distance and period using the following formula:…”

“…A short period of UV irradiation improved interfacial bonding strengths between composite resin artificial teeth and auto-polymerized resin 13) . Moreover, the bond strength between the FRC post and the core build-up resin was improved by UV irradiation 14) , which is considered to improve the surface characteristics of several dental appliances. However, the effects of UV irradiation on dental appliances might vary due not only to the types of irradiated materials but also the UV irradiation period.…”

“…Several studies reported the usage of UV irradiation for dental appliances, such as artificial teeth 13) , FRC posts 14) , and dental implants 21) . A short period of UV irradiation improved interfacial bonding strengths between composite resin artificial teeth and auto-polymerized resin 13) .…”

“…Several investigators have reported on effective surface treatments of FRC posts to improve the bonding, such as sandblasting treatment using Al 2O3 particles [6][7][8][9][10] , etching treatment with organic solvents containing dichloromethane 6,9) , etching treatment with acid solutions using hydrogen fluoride [7][8][9][10] , silane coupling treatment [7][8][9][10] , plasma irradiation [10][11][12] , and ultraviolet light (UV) irradiation 11,13,14) . The sandblasting and etching treatments increase the surface microroughness to create mechanical interlocking.…”