The effect of Er,Cr:YSGG laser application on the micropush-out bond strength of fiber posts to resin core material.

Objective: The aim of this study was to compare the effects of erbium, chromium: yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser application to different surface treatments on the micropush-out bond strengths between glass and quartz fiber posts and composite resin core material.

Background Data: Different types of lasers have been used as an alternative to airborne particle abrasion and other surface treatment methods to enhance the bond strength of dental materials. However, there is no study regarding the use of Er,Cr:YSGG laser as a surface treatment method for fiber posts in order to improve the bond strength.

Materials And Methods: Ninety-six quartz and 96 glass fiber posts with a coronal diameter of 1.8 mm were randomly divided into eight groups according the surface treatments applied. Gr 1 (control, no surface treatment), Gr 2 (sandblasting with 50 μm Al2O3), Gr 3 (9 % hydrofluoric acid for 1 min), Gr 4 (24% H2O2 for 1 min), Gr 5 (CH2Cl2 for 1 min), Gr 6 (1 W), Gr 7 (1.5 W), and Gr 8 (2 W) Er,Cr:YSGG laser irradiation. The resin core material was applied to each group, and then 1 mm thick discs (n=12) were obtained for the micropush-out test. Data were statistically analyzed.

Results: For the quartz fiber post group, all surface treatments showed significantly higher micropush-out bond strengths than the control group (p<0.05), except for the 2 W Er,Cr:YSGG laser group. For the glass fiber post group, H2O2, CH2Cl2, Al2O3, and laser application (1 W, 1.5 W) (p<0.05) enhanced the bond strength between the post and core material. However, the hydroflouric acid group showed the lowest bond strength values.

Conclusions: The type of post and surface treatment might affect the bond strength between fiber posts and resin core material; 1 W and 1.5 W Er,Cr:YSGG laser application improved adhesion at the post/core interface.