LAUSR

OBJECTIVE It is important to protect the patient's oral mucosa from injury caused by inappropriate oral care. We established anin vivo model of intraepithelial injury of the oral mucosa and assessed the effects of inappropriate dental apparatus use on inflammatory response of macrophages in rats. DESIGN Using this model, swabbing was performed to the labial mucosa of rats with the interdental brush, and the tissue samples were processed for histological evaluation. RESULTS CD 68-positive macrophage-like cells appeared only in the subepithelial region after intraepithelial injury in the presence and absence of antibiotics. After intraepithelial injury, interleukin-1β levels did not increase beyond those observed in intact rats. The number of bacteria in the lip increased slightly and decreased promptly. In the ear, intraepithelial injury caused an inflammatory response with macrophages infiltrating into the intraepithelial region as well as the subepithelial region, increased interleukin-1β production, and high bacterial levels around tissues. CONCLUSION Our results highlight the importance of protecting against the intraepithelial injury during oral care procedures, and these findings would contribute to oral care risk management in the future.