Clinical Evaluation of CO Laser Vaporization Therapy for Oral Lichen Planus: A Single-Arm Intervention Study.

The purpose of this study is to evaluate the efficacy of CO laser vaporization therapy for oral lichen planus (OLP) refractory to conservative treatments. The study group comprised 16 patients with clinically and histologically diagnosed OLP. They underwent conservative treatment for 3 months using an adrenal cortex hormone ointment and azulene sulfonate sodium hydrate gargle. Patients who showed no improvement with conservative treatment underwent CO laser vaporization therapy (3 W, continuous-wave mode). The assessment was performed using the numerical rating scale (NRS) as a subjective indicator and the Thongprasom sign score (TSS) as an objective indicator of OLP. These two scales were recorded during examinations performed before treatment and then at 7 days, 1, 3, and 6 months, and 1 year after irradiation. Differences between preirradiation and each point of time after irradiation were tested by Wilcoxon's signed-rank tests. Laser irradiation was administered to 9 patients with 11 sites. The NRS score and TSS decreased at all 11 sites (100%) and 10 sites (90.9%) at 1 year after irradiation compared with preirradiation scores. The NRS score and TSS were statistically lower ( < 0.05) at 1 and 3 months (short-term) and 6 months and 1 year (mid-long-term) after irradiation than the preirradiation scores. There were no patients with malignant transformation during the study period. These single-arm clinical trial results show the efficacy of CO laser vaporization therapy for OLP refractory to conservative treatment.