A Study on the Removal of the Gingival Melanin Pigmentation by CO2 Laser Irradiation

Abstract

The possibility about the removal of gingival melanin pigmentation with CO2 laser is confirmed by our previous researches which were carried out histopathologically using dog's gingival melanin pigmentation. Since then, we have been carrying out the clinical study of the removal of human melanin pigmentation by CO2 laser.For this study, 5 patients aged 20 to 49 years with gingival melanin pigmentation were used. CO2 laser was irradiated on the surface of the pigmented gingiva under the following conditions: output; 6-8 (W), time; 0.1-0.2 (S), defocused beam of spot size; 4mm. The irradiated gingiva was evaluated macroscopically and histopathologically. The histopathological changes were invested by hematoxylin-eosin staining and Masson staining for the differential diagnosis of melanin pigmentation cells. Immediately after irradiation, the gingiva surface showed white color and bulla-like appearance. No hemorrhage and no epidermal detachment were observed. The damege to the gingival tissue was slight in comparison with the conventional surgical method. One week after irradiation, it was revealed that the disappearance of melanin pigmentation on the lased gingiva was significant in all cases. Histologically, the pigmented-laden cells could not be found and no inflammatory cell infiltrati on was also observed.From the above clinical and histopathological results, we have concluded that it was possible to remove the human gingival melanin pigmentation by CO2 laser irradiation.