Diagnostic Efficiency of Salivary Cortisol in Detecting Oral Lichen Planus: A Systematic Review

Introduction: Cortisol, the primary glucocorticoid in humans, is a well-established biomarker of psychological stress and anxiety. Because oral lichen planus (OLP) can develop or worsen during periods of heightened stress, salivary cortisol has been investigated as a potential indicator of disease activity. This review aimed to assess salivary cortisol concentrations in individuals with OLP compared with healthy controls. Salivary cortisol provides a noninvasive measure of biologically active free cortisol and reflects acute and chronic stress responses. As OLP is a chronic immune-mediated mucosal disorder with a recognized psychosomatic component, evaluating salivary cortisol may help clarify the role of stress in its onset, persistence, and severity. Materials and Methods: A systematic search of Web of Science, PubMed, and Google Scholar was conducted for English-language studies published from May 2004 to May 2024. Both MeSH terms and text words related to OLP and salivary cortisol were used. After screening and eligibility assessment, observational studies comparing salivary cortisol levels in OLP patients with healthy controls were critically appraised using the Joanna Briggs Institute (JBI) checklist. Results: Fifteen studies met the inclusion criteria, comprising a total of 1028 participants. Across the included studies, OLP patients consistently demonstrated higher salivary cortisol levels than controls. Most studies using enzyme-linked immunosorbent assay reported significant between-group differences, supporting an association between elevated cortisol and OLP. Similar trends were observed in studies using other immunoassay techniques. Conclusions: The available evidence indicates that OLP is frequently associated with elevated salivary cortisol levels, underscoring the influence of psychological stress on disease expression. Supportive psychological interventions, when used alongside conventional therapy, may help improve stress regulation and overall patient outcomes.