Effect of Adjunctive Systemic Vitamin E on Clinical Parameters and Salivary Total Antioxidant Capacity in Symptomatic Oral Lichen Planus Patients: Randomized-controlled Clinical Trial

The current study is a randomized-controlled clinical trial that follows CONSORT guideline. The current trial include 30 symptomatic OLP patients in two parallel groups (intervention - topical triamcinolone acetonide adhesive paste and Vitamin E capsule, control - topical triamcinolone acetonide adhesive paste and placebo capsule), with allocation ratio 1:1. Participants were recruited from the pool of the Diagnostic center and the Out-Patient Clinic of Oral Medicine and Periodontology Department, Faculty of Dentistry, Cairo University, Egypt between 2016 and 2017.

This clinical trial followed the principles of the Helsinki Declaration and was approved by the Research ethics committee of Faculty of Dentistry, Cairo University, Egypt (Code: 15733). Each participant was informed about the details of the study and signed a written consent.

Patients were diagnosed clinically and histopathologically (when required). Inclusion criteria included erosive and atrophic OLP patients who agreed to take supplied medications. Exclusion criteria included reticular OLP patients, patients receiving systemic treatment for OLP during the eight weeks prior to the study, patients receiving topical medications for OLP during the four weeks prior to the study, patients suffering from systemic disease; pregnant ladies and lactating ladies.

Interventions:

The intervention was 0.1% triamcinolone acetonide adhesive paste (Kenacort A Orabase - Dermapharm) and 400 mg Vitamin E capsule (Vitamin E 400 - Pharopharmaceuticles) for the experimental group and 0.1% triamcinolone acetonide adhesive paste (Kenacort A Orabase - Dermapharm) and identical placebo capsule for the control group.

Patients were instructed to apply triamcinolone acetonide regularly four times a day after meals and before sleeping for four weeks and to refrain eating and drinking for 30 minutes after the application. In addition, patients were asked to take one capsule (Vitamin E or placebo) once daily at morning.

Outcomes:

Pain intensity was evaluated using numerical rating scale (NRS) at baseline, daily during the first week, then weekly for four weeks. NRS ranges from 0 to 10, with 0 indicating "no pain" and 10 indicating "pain as bad as you can imagine".21 Clinical improvement of the oral lesions was scored using Thongprasom et al. scale at baseline and weekly for four weeks. In Thongprasom et al. scale, lesions are given score as follows: 0, no lesions, normal mucosa; 1, Mild white striae, no erythematous area; 2, White striae with atrophic area < 1 cm2; 3, White striae with atrophic area > 1 cm2; 4, White striae with erosive area < 1 cm2 and 5, White striae with erosive area > 1 cm2.22 Salivary level of TAC was evaluated using ELISA kit. Unstimulated whole saliva samples were used for determination of TAC using ImAnOx (TAS/TAC) Kit provided by Immun Diagnostik, Germany. Participants were asked to refrain eating, drinking or using saliva stimulators for one hour before sample collection. Participants were asked to swallow, then tilt their head forward and expectorate saliva into a centrifuge tubes for 5 minutes without swallowing. The saliva samples were frozen at -70°C, until analysis. The saliva samples were centrifuged at 4500 g for 15 minutes.