Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet Laser for Root Conditioning and Reduction of Postoperative Morbidity in the Treatment of Gingival Recession Defects: A Randomized Controlled Clinical Trial.

Objective: This clinical trial evaluates the effect of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) root surface biomodification and laser harvesting of de-epithelialized gingival graft (DGG) on root coverage clinical outcomes and postoperative morbidity, and compares this to the conventional blade-harvested DGG method without Er,Cr:YSGG root surface biomodification in treatment of Miller's class I, II gingival recessions (GR). Background: The application of laser technology to enhance tooth root coverage clinical outcomes as well as the impact of laser on postoperative morbidity after harvesting autogenous soft tissue grafts requires further research. Methods: This study is a randomized, single-blinded controlled trial, including 24 volunteers with isolated GR defects. They were allocated into three treatment groups to receive one of the following three interventions: blade-harvested DGG (control group: B-DGG); Er,Cr:YSGG-harvested DGG and root surface biomodified [test 1 group: L-laser-harvested DGG (L-DGG)/laser root biomodification (LRB)]; and B-DGG and Er,Cr:YSGG root surface biomodification (test 2 group: B-DGG/LRB). Clinical and radiographic parameters were recorded at baseline (1 week before surgery) and 3, 6, and 9 months postoperatively. Results: Root coverage did not show a statistically significant difference between control and test groups. Statistically significant differences were found for Visual Analog Scale on the day of surgery and day 3 and 4 postoperatively, as well as pain medication on the day of surgery favoring the L-DGG group. Conclusions: The use of Er,Cr:YSGG laser in root surface biomodification improved root coverage outcomes at 9 months. Even these changes were not statistically significant from the control group; the L-DGG technique was associated with decreased postoperative morbidity in the palatal donor site.

Comparative study between laser and conventional techniques for class V cavity preparation in gamma-irradiated teeth (in vitro study).

OBJECTIVE: The purpose of this study was to compare laser with conventional techniques in class V cavity preparation in gamma-irradiated teeth. METHODS: Forty extracted human teeth with no carious lesions were used for this study and were divided into two main groups: Group I (n = 20) was not subjected to gamma radiation (control) and Group II (n=20) was subjected to gamma radiation of 60 Gray. Standard class V preparation was performed in buccal and lingual sides of each tooth in both groups. Buccal surfaces were prepared by the Er,Cr:YSGG laser (Waterlase iPlus) 2780 nm, using the gold handpiece with MZ10 Tip in non-contact and the "H" mode, following parameters of cavity preparation - power 6 W, frequency 50 Hz, 90% water and 70% air, then shifting to surface treatment laser parameters - power 4.5 W, frequency 50 Hz, 80% water and 50% air. Lingual surfaces were prepared by the conventional high-speed turbine using round diamond bur. Teeth were then sectioned mesio-distally, resulting in 80 specimens: 40 of which were buccal laser-treated (20 control and 20 gamma-irradiated specimens) and 40 were lingual conventional high-speed bur specimens (20 control and 20 gamma-irradiated specimens). RESULTS: Microleakage analysis revealed higher scores in both gamma groups compared with control groups. Chi-square test revealed no significant difference between both control groups and gamma groups (p=1, 0.819, respectively). A significant difference was revealed between all 4 groups (p=0.00018). CONCLUSION: Both laser and conventional high-speed turbine bur show good bond strength in control (non-gamma) group, while microleakage is evident in gamma group, indicating that gamma radiation had a dramatic negative effect on the bond strength in both laser and bur-treated teeth.