Influence of ErCr : YSGG laser treatment on microtensile bond strength of adhesives to enamel

Cardoso M. V. , De Munck J., Coutinho E., Ermis R. B. , Van Landuyt K., De Carvalho R. C. R. , ...More

OPERATIVE DENTISTRY, vol.33, no.4, pp.448-455, 2008 (Peer-Reviewed Journal) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 4
  • Publication Date: 2008
  • Doi Number: 10.2341/07-124
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.448-455


The current trend towards minimum-intervention dentistry has introduced laser technology as an alternative technique for cavity preparation. This study assessed the null hypothesis that enamel prepared either by ErCr:YSGG laser or conventional diamond bur is equally receptive to adhesive procedures. The buccal and lingual surfaces of 35 sound human molars were prepared with ErCr:YSGG laser or a medium-grit diamond bur. One etch&rinse (OptiBond FL) and three self-etch adhesives (Adper Prompt L-Pop, Clearfil SE Bond and Clearfil S-3 Bond) were applied on laser-irradiated and bur-cut enamel, of Z100. The micro-tensile bond strength (mu TBS) was determined after 24 hours of storage in water at 37 degrees C. Prepared enamel surfaces and failure patterns were evaluated using a stereo-microscope and a field-emission-gun scanning electron microscope (Feg-SEM). The mu TBS to laser-irradiated enamel was significantly lower than to bur-cut enamel (p < 0.05), with the exception of Clearfil S-3 Bond, which bonded equally effectively to both substrates. The latter presented the highest mu TBS on laser-irradiated enamel, though it was not statistically different from the mu TBS of OptiBond FL. SEM analysis revealed significant morphological alterations of the laser-irradiated enamel surface, such as areas of melted and recrystalized hydroxyapatite and deep extensive micro-cracks. In conclusion, the bonding effectiveness of adhesives to laser-irradiated enamel depends not only on the structural substrate alterations induced by the laser, but also on the characteristics of the adhesive employed.followed by the application of a 5-6 mm build-up