Bond strength of sealants to enamel after different etching procedures

Methods: Forty extracted premolars with the roots sectioned 2 mm coronal to cemento-enamel junction were used in this study. All teeth were embedded in auto-polimerizing acryling resin with the labial surfaces facing up. Enamel surfaces were flattened and 2.5 mm diameter bonding area was demarcated. The specimens were then divided randomly into four groups. Group I: etched with acid(37 % phosphoric acid, SDI Super etch) and a sealant (Clinpro TM/3M ESPE) was placed without bonding agent, Group II: etched with acid and the sealant was placed with a bonding agent (Single Bond, 3M ESPE), Group III: etched with Er,Cr:YSGG laser (Waterlase MD/ Biolase) at 1.25W/10 Hz and sealant was placed without bonding agent, Group IV: etched with Er,Cr:YSGG laser at 1.25 W/10 Hz and sealant was placed with the bonding agent. After the sealed teeth were thermocycled (X1000, 5 and 55 C degrees ), shear bond strengths of samples were tested in a universal testing machine. The results were analysed by Kruskal Wallis multiple comparison test.

Results: There were no statistically significant differences among the shear bond strength of fissure sealants etched with acid and Er, Cr : YSGG laser and placed with or without bonding agent (p>0.05).

Conclusion: Based on these results and within the limitation of this in vitro study, bonding agent was not able to increase the effectiveness of bonding of fissure sealant to acid or Er, Cr : YSGG laser etched enamel.