[Some phenolic compounds stimulate the proliferation of human pulpal fibroblasts]

Phenolic compounds are widely used in dental clinics especially for the treatment of inflammatory responses of the dental pulp. However, the role of these agents in the repair of pulpal connective tissue is unclear. In the present study, an effect has been identified in several phenolic compounds that can stimulate active proliferation of pulpal fibroblasts. Human pulpal fibroblasts (HPF) were obtained from subcultures of between 5 and 15 passages. HPF in tissue culture plates were incubated in serum-free medium with several phenolic compounds at concentrations of 10(-8) M to 10(-4) M for 4 days. After incubation, cells were fixed, stained in culture plates and the number of nuclei counted. Phenol (10(-8) M to 10(-4) M) stimulated proliferation in a quiescent population of HPF, and the number of cells increased 27-41% compared with unstimulated cells. When HPF were incubated with p-chlorophenol, guaiacol, thymol or eugenol, there was a significant activation of cell proliferation (5 to 22%). Moreover, cell viability of the HPF was not influenced at all, except in the cases of p-chlorophenol and eugenol at concentrations of 10(-4) M. These observations may contribute to an understanding of the relationship between the stimulative effects of phenolic compounds and pulpal tissue repair.