To study the clinical efficacy of basic periodontal therapy combined with local medication for erosive oral lichen planus (OLP).

56 patients with erosive oral lichen planus and periodontitis were randomly divided into two groups: experimental group and control group. Experimental group received basic periodontal therapy and drug therapy. Control group received drug therapy only. For all patients, the clinical symptoms of OLP were examined at baseline, one month after therapy and six month after therapy.

One month after therapy, there was significant difference in the clinical effects of treatments between experimental group (92. 86%) and control group (67. 86%) (P ＜ 0. 05). Six month after therapy, there was significant difference in the clinical effects of treatments between experimental group (85. 71%) and control group (57. 14%) (P ＜ 0. 05).

Basic periodontal therapy can effectively relieve the clinical symptom of OLP in erosiveoral lichen planus patients with chronic periodontitis, indicating that periodontal intervention has positive therapeutic effect.