ORIGINAL

Ultrastructural demonstration of rat myofibroblasts in phenytoin-induced gingival overgrowth

Abstract

This ultrastructural study of phenytoin-induced gingival overgrowth in rats demonstrates a statistically significant increase in myofibroblasts (18.5 cells/1×10⁴μm² area; control, 5.7;p<0.01, Wilcoxon test). The increased presence of these cells may be interpreted by either of two mechanisms: 1) phenytoin, along with the promotional influence of inflammation, elicits excessive repair (overgrowth) similar to that of wounds where myofibroblasts play an important role, or 2) this lesion reacts like tumor or other active proliferative conditions where myofibrolasts represent one form of host-tissue response.