Efficacy of liquid nitrogen and electrocautery assisted gingival depigmentation in term of patient's perception, histological wound healing - A randomized triple blind clinical trial

BACKGROUND: Hyper-melanin pigmentation of the gingiva (GMP) is one of the imperative contributory factors for smile-sensitive individuals. Numerous gingival depigmentation (GD) procedures have been attempted in the literature to evaluate the clinical outcome mostly. Hence, a randomized clinical-histopathological triple-blinded trial was planned to evaluate the pain experienced by the patient, gingival wound healing, and density of melanocytes following liquid nitrogen-assisted GD (LNAGD) and electrocautery-assisted GD (ECAGD) procedures. MATERIALS AND METHODS: Thirty-two arches with bilateral physiologic labial/buccal GMP extending from distal aspect tooth #14–24 and #34–44 in 16 healthy individuals were selected and were equally treated with LNAGD and ECAGD techniques. Dummett oral pigmentation index and Hedin melanin index were evaluated at baseline and 3 months' postoperatively (PO). The visual analog scale was utilized for the intensity of pain assessment at baseline (immediately after treatment) and 1(st) day and 7(th) day PO. Histological wound healing and density of melanocytes were evaluated using Gal et al.'s wound-healing assessment index and Patsakas et al.'s criterion, at baseline (0), 8, 24, 72, and 96 h; 1(st), 2(nd), 3(rd), and 4(th) week; and 3 months and at 0 and 3 months' PO, respectively. Statistical analysis was done using one-way ANOVA, post hoc Tukey, unpaired, and paired “t” test. RESULTS: Both groups showed a statistically significant influence on the parameters evaluated. CONCLUSION: The LNAGD had a substantial superior result in terms of early wound healing, reduction in density of melanocytes, reduction in pain experienced by the patient, with reduction and delay in the recurrence of GMP.