Influence Of Erbium Laser On Dentin Surface Of The Tooth

To compare the microleakage between the dentine surface and the composite after etching the dentine with orthophosphoric acid and Er,Cr:YSGG laser. 60 human third molars, on which two class V cavities were prepared, were randomly divided into two groups (n=30) following the dentine surface treatment (Group 1: Etching the dentine with 37.5% orthophosphoric acid; Group 2: Etching the dentine with the Er,Cr:YSGG laser with an average power of 4.5W, frequency of 50Hz, energy of 90mJ, pulse duration 60µs, 90% Water, 80% Air, 1 mm distance at a 40-60° angle). Both of the groups were further divided in to 2 subgroups: with and without thermocycling. Each subgroup contained the following three generations of adhesive systems IV, V and Universal adhesive system. All the specimens were immersed with methylene blue in order to evaluate the dye penetration. Statistical analyses were done using STATISTICA 6.0 software package from StatSoft Inc. Significant statistical differences were observed inside each group with and without thermocycling (р≤0,05). No statistically significant differences between orthophosphoric acid etched and Er,Cr:YSGG laser etched groups were observed. Er,Cr;YSGG laser may be used for etching the dentine since the results showed no statistical significant difference as compared to orthophosphoric acid etching. The 5th generation of the adhesive system on the dentine showed the lowest microleakage with both orthophosphoric acid etching and Er,Cr;YSGG laser surface modification.