Title: Effect of bleaching agents on oral mucosa
Abstract:
Tooth bleaching is a common procedure in dentistry. Many controversies exist about the risk of tissue damage due to the contact of bleaching agents with the oral mucosa. The purpose of this study was to evaluate the effect of short-term topical application of carbamide peroxide and hydrogen peroxide on the oral mucosa of rats.
Methods: Fifty-six male Wistar rats were selected, and 10% carbamide peroxide and 35% hydrogen peroxide were topically applied to the gingival mucosa once a week for four consecutive weeks. On the control side, only distilled water was used. The animals were killed on days 7, 14, 21 and 28 after the last application. The gingival tissue was fixed in formalin for 24 hours and embedded in paraffin. Data were analyzed by the McNemar test. P<0.05 was considered significant.
Results: The results showed that the topical application of 10% hydrogen peroxide and 35% hydrogen peroxide increased dysplasia in the epithelial layer of the oral mucosa of rats. Kidney and liver histologic findings were normal. 14 rats exhibited intraepithelial vesicles.
Conclusion: This study showed that the local application of hydrogen peroxide and carbamide peroxide can cause mild to severe dysplasia changes in the mucosa of rats. In addition, these agents might cause pemphigus, according to the study results.
