Oral lichen planus (OLP) is a chronic disease without any definitive treatment. Local corticosteroids are often prescribed, but their efficacy has been questioned by many studies. The purpose of this study was to investigate the effect of nano‑based triamcinolone acetonide gel (NT) and compare it with conventional triamcinolone gel (CT) on OLP.

In this triple‑blind randomized clinical trial study, 40 patients with Erosive OLP were divided into two groups receiving (CT) and (NT). The patients were requested to apply them four times a day for 2 weeks. The severity of pain was evaluated through visual analog scale, the size of lesions was measured with paper lace, and the appearance of lesions was examined adopting Thongprasom scale . Findings will be significant via independent t‑test or Chi‑square test with P < 0.05.

The severity of pain in NT group was 4.9 ± 0.7 cm before the treatment and 1.5 ± 0.9 after that, whereas in CT group, it was 4.9 ± 0.8 and 1.8 ± 0.9, respectively . The mean size of the lesions in NT group was 2.1 ± 1.1 cm before the treatment and 0.8 ± 1.1 afterward, whereas in CT group, was 2.2 ± 1.1 and 1.3 ± 1.1, respectively. The OLP appearance before and after the study in NT group was 4.5 ± 0.5 and 0.8 ± 0.6, respectively, whereas in CT group was 4.6 ± 0.5 and 0.9 ± 0.7 (P = 0.3). Among these variables, only Thongprasom scale on the 6th and 14th days had a significant reduction in NT group in comparison with CT group.

NT has a better impact on OLP in comparison with CT, but this difference is not statistically significant.