Dentin Barrier Test With Er:YAG Laser Treated Dentin

Method: The cytotoxicity of  I Bond (Heraeus Kulzer),  G bond (GC Corporation) and Vitrebond (3M ESPE) (positive control) was analyzed in a dentin barrier test device using three-dimensional bovine pulp derived cell cultures. Cell cultures were placed in direct contact with the pulpal side of dentin discs. Test materials and negative control material were introduced into the cavity side of the Er:YAG laser treated and untreated dentin discs according to the manufacturer’s instructions.  Pulpal part of the perfusion chamber was perfused with cell culture medium (2ml/h). After an exposure period of 24 h, the cell survival was determined by the MTT assay. The mean values of control tissues were set to represent 100% viability. Data were analyzed using Kruskal-Wallis and Mann-Whitney U-test.

Result: G bond and Vitrebond was cytotoxic to the pulp derived cells (p<.05) and  I Bond was similar with the negative control group (p>.05) on untreated dentin. However all tested materials were not cytotoxic when they are applied on Er:YAG laser treated dentin (p>.05). 

Conclusion: Er:YAG laser treatment of dentin could protect the pulp cells from toxic substances of  tested materials. Taking into consideration the limitations of this vitro study, the Er:YAG laser treatment of dentin before restoration might be an option to  decrease the cytotoxic effects of the dental materials and further research is required for clinical applications.