The effect of low-level laser therapy on complications after crown lengthening surgery-A double-blind clinical trial

Background & aim: The formation and persistence of surgical wounds can cause a variety of complications, including pain, swelling, inflammation, re-infection, dysfunction, delay in the healing process and aesthetic problems. So far, various methods have been proposed to reduce these complications, one of which is the use of low-level lasers. The aim of this study was to investigate the effect of low-level laser on complications such as edema, discoloration and pain after crown-lengthening surgery. Methods: In this double-blind split-mouth clinical trial, 12 people who needed to receive crown-lengthening surgery on two bilateral premolars were studied. Immediately after surgery, as well as on the first and third days after surgery, each volunteer randomly received laser radiation on one side of the jaw. Despite placing the tube in the mouth, no irradiation was performed on the other side. Tissue edema and tissue color were assessed on the first, third and seventh days after surgery. Pain intensity was measured 24, 48 and 72 hours after surgery. The data were entered into SPSS software version 22. Kendall’s test was used to assess tissue edema and tissue color and Friedman and Mann-Whitney tests were used to assess pain intensity. Results: The improvement of tissue edema in the irradiated group was significant compared to the non-irradiated group during the first week, but the improvement of tissue color did not show a significant difference between the two groups. The difference in pain intensity between the groups at 24, 48 and 72 hours post- surgery was not statistically significant either, And the improvement of pain intensity during consecutive days was not significant in the irradiated group. Conclusion: In the present study, low-level laser had no significant effects on the improvement of tissue color and the reduction of postoperative pain after crown-lengthening surgery in the case group compared with the control group, But it was effective in improving tissue edema after surgery.