Supplementary zinc and vitamin D in management of symptomatic oral lichen planus: a three-arm randomized clinical trial.

Background: Oral lichen planus (OLP) is a chronic inflammatory disease affecting the oral mucosa, with immune mediated pathogenesis. Both zinc and vitamin D are essential micronutrients implicated in OLP pathogenesis, with zinc influencing epithelial growth, wound healing, and oxidative stress mitigation, while vitamin D modulates immune cell function, cytokine activity, and keratinocyte behavior. The current trial was conducted to assess the effect of topical corticosteroid supplemented with zinc or vitamin D compared to topical corticosteroid in management of symptomatic oral lichen planus.

Methods: Forty-two patients diagnosed with symptomatic oral lichen planus (atrophic, erosive, or bullous types) were included in the study, based on clinical examination and histopathological confirmation in accordance with the modified World Health Organization (WHO) criteria (2003). Participants were divided randomly into three parallel groups. Group I received topical corticosteroid; Group II received topical corticosteroid with systemic zinc; Group III received topical corticosteroid with systemic vitamin D. The outcome measures included pain intensity using Visual Analogue Scale and clinical improvement using Thongprasom et al. scoring system. Treatment lasted for 8 weeks; patients were clinically evaluated at baseline and on weekly basis.

Results: Intergroup comparisons revealed that by Week 3, pain scores were significantly lower in Groups II and III compared to Group I. Intragroup analysis showed significant reductions in pain scores over time for all groups, with Group II showing the most pronounced decrease from baseline to Week 7. Thongprasom scores decreased significantly in all groups, with Group II showing the most significant reduction by Week 8.

Conclusions: Systemic zinc supplementation combined with topical corticosteroid can be used as an adjunct therapy for OLP management. Topical corticosteroid supplemented with vitamin D has comparable effect to topical corticosteroid alone on pain and clinical improvement in symptomatic OLP.

Clinical trial registration: NCT04765267 (full protocol can be accessed). Date of Initial Clinical Trial Registration: 4 February 2021.