Influence of chlorhexidine rinsing on the healing of oral mucosa and osseous lesions.

The influence of chlorhexidine rinsing on wound healing was studied using standardized, open mucosal-osseous wounds in the left side of the palate in Wistar rats. In five test groups, each containing 10 rats, rinsing was performed twice daily for 30 sec with 0.1, 0.2 and 0.5% chlorhexidine solution, chlorhexidine solution vehicle, and Ringer solution. A sixth test group (control) was not rinsed at all. Seven days postoperatively, wound healing was evaluated clinically (size of the defect) and histomorphometrically (percent composition of mature connective tissue, immature connective tissue, granulation tissue, fibrin with granulocytic infiltrate). Clinically it was clear that wound healing was best in those animals that rinsed with Ringer solution, and worst in those that rinsed with 0.5% chlorhexidine solution. Increasing concentration of chlorhexidine caused a delay in wound healing, which in the following cases resulted in significant differences: rinsing with Ringer solution and vehicle versus all concentrations of chlorhexidine, no rinsing versus 0.5% chlorhexidine. Intensive rinsing with high concentrations of chlorhexidine may, after oral surgical operations, especially surgery in which bone is exposed, result in delay and disturbance of wound healing in humans.