PRF in orabase will be applied as a pack material on chronic oral ulcers of chronic multiple oral lesions compared to conventional topical steroid therapy with clobetasol propionate 0.05% in orabase. The outcomes measured are Pain alleviation as Primary outcome and Clinical improvement in terms of Ulcer size, Number and Mucositis score as Secondary outcomes. Time frame for outcomes assessment will be Daily for 7 Days regarding pain score and weekly for 2 weeks regarding clinical improvement.

The management of oral ulcers and mucositis specially the resistant types such as oral ulcers due to auto-immune diseases is a major concern by the dentists through all the world. Topical corticosteroids, analgesics, Laser bio modulation all have been proposed as treatments with limited efficacy in many cases. There are few number of clinical trials on Plasma preparation in management of oral mucositis and oral ulcers. Platelet rich fibrin (PRF) is one of the platelet concentrates. The preparation protocol of PRF is simple and easy, could be prepared autologous and immediately placed on the oral ulcers and mucositis.

Subjects and Methods: A non Randomized clinical trial will be conducted. Ten patients with different resistant oral ulcers and mucositis were enrolled. all with grade 4 WHO mucositis score. The initial numerical ratting score of pain is 10. For all patients 20 ml blood sample will obtained in plain blood vacutainer, centrifuged for 15 minutes on 3000 rpm. The resultant gel, obtained and squeezed to prepare a membrane, the membrane will be mixed with orabase and placed over the oral ulcers and mucositis over a piece of gauze. The patients will be instructed not to eat or drink for 2 hours after application. The remaining serum after squeezing was mixed with equal amount of orabase and used topically on the oral mucositis and ulcers.

Clobetasol Propionate 0.05% in orabase will be applied to 10 control patients 3 times per day for one week.

The steps will be repeated after one week if the patients' symptomatic scores for WHO and numerical rating score were not zero.

Inclusion Criteria:

• Patients with Oral ulcers due to Benin mucous membrane pemphioid, Pemphius vulgaris and Steven Johnson's Syndrome with mucositis score 4 and pain score 10

Exclusion Criteria:

• patients with any systemic other systemic condition

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