Melanocyte Response Following Depigmentation by Cryosurgery and Mucosal Excision: A Comparative Clinical and Histopathological Study.

AIMS

The main aim of this study was to evaluate the melanocyte response following depigmentation by cryosurgery and mucosal excision at both clinical and histopathological levels during 6 months.

SUBJECTS AND METHODS

A total of 15 individuals, aged 25-45 years with hyperpigmentation on the facial aspect of the gingiva present in the esthetic zone were included. A split-mouth approach was used, wherein one side received depigmentation by a scalpel and the other side received cryotherapy, with the choice of the therapy and side chosen by the spin of the coin. For determining the melanocyte assay, a small amount of gingival tissue that was excised was studied under a special staining technique, i.e., Masson-Fontana method for melanin, a histochemistry procedure which determines the activity of melanin both quantitatively and qualitatively. Clinical and histological observations for the intensity of pigmentation were recorded at baseline and 6 months after surgery.

STATISTICAL ANALYSIS USED

Paired and unpaired -test. Results: The mean value of the Dummett Oral Pigmentation Index (DOPI) was 2.44 ± 0.51 at baseline; following depigmentation with scalpel technique, the mean DOPI was 1.05 ± 0.23 at 6 months; and there was a statistically significant difference in the mean DOPI when compared with that of the baseline ( = 0.001). Following depigmentation with cryosurgery technique, the mean DOPI was 0.33 ± 0.48 at 6 months which also varied statistically significantly with that of the baseline ( = 0.001). The mean value of melanin histopathological count (MHC) was 95.53 ± 9.03 at baseline; following depigmentation with the scalpel technique, the mean DOPI was 89.49 ± 7.56 at 6 months, which was not statistically significant ( = 0.795). Following depigmentation with the cryosurgery technique, the mean MHC was 75.38 ± 5.63 at 6 months, which was not statistically significant ( = 0.285).

CONCLUSIONS

The mean histologic count of the melanocytes, which accounts for the re-pigmentation process has shown low recurrence values in cryosurgery over the scalpel technique even though the difference was not statistically significant.