Lichen planus is the most common skin disease that affects the oral mucosa. Oral Lichen Planus is a T-cell-mediated autoimmune disorder. In the current study, for the first time, an oral cavity condition in skin patch tests with adding saliva is simulated. In addition, the patch results are compared with healthy subjects. Forty-one OLP patients and 63 healthy subjects were enrolled in the study. All participants were provided with patch tests, including allergens, in combination with saliva in chambers. Allergens from the European baseline (standard) series selected according to the most prevalent positive results in the previous study were applied. Positive results of Mercury and Cobalt tests were significantly higher in the case group. In this study, the differentiation of patients with lichen planus and lichenoid was identified according to the Van der Meij & Van der Waal criteria. The patch test was conducted for healthy individuals as well. The most important of all was the use of patients' saliva in the patch test, done for the first time in this field. In the case of OLP, a patch test can help identify positive reactions to dental materials; thus, the replacement of dental restorations may be needed.