Diagnostic Infrared Thermography of the Tongue and Taste Perception in Patients with Oral Lichen Planus: Case-Control Study

Oral lichen planus (OLP) is a chronic inflammatory disease of autoimmune origin that affects the skin and mucous membranes. The aim of this study was to assess the effectiveness of infrared thermography (IRT) as a diagnostic tool in patients with oral lichen planus (OLP), as well as disturbances in taste perception, in cases with and without tongue involvement. A case-control study was carried out in a sample of 87 patients divided into three groups: healthy individuals (controls; n = 43), OLP patients without involvement of the tongue (n = 24), and OLP patients with involvement of the tongue (n = 20). The patient symptoms and the clinical characteristics of the lesions were assessed. Four thermal images of the tongue were obtained using IRT: dorsum, right and left lateral surface, and tip of the tongue. General taste perception capacity and subjective sweet, acid, salty, and bitter sensation were evaluated in all three groups. There were no statistically significant differences in the IRT values among the three groups (p >= 0.05). In the OLP patients with involvement of the tongue, significantly higher values were observed in the mixed forms of the disease (p = 0.032). The OLP patients with and without involvement of the tongue showed no significant alterations in taste sensation (p = 0.69). IRT may serve as a complementary tool for assessing the activity of OLP with involvement of the tongue. However, more research is needed in this field.