1997 Volume 39 Issue 2 Pages 217-225
To clarify the changes in cell proliferative ability of fibroblasts and the mechanism of nifedipine (NF) -induced gingival overgrowth, a representa-tive medication-induced gingival overgrowth, an immunohistochemical study was performed using anti-proliferating cell nuclear antigen (PCNA) antibody. The gingival tissues from patients on NF with gingival overgrowth (responder, R) were compared with those of patients on NF without overgrowth (non-responder, NR), non-drug taking patients with enlarged gingivae caused by dental plaque (ND) and healthy control subjects (Control) on the basis of distribution and density of PCNA positive cells in the tissues. Five patients in each group were randomly selected and biopsies were obtained during periodontal surgery or tooth extrac-tion, processed routinely in paraffin wax and seri-ally sectioned. These specimens were immunos-tained by mouse anti-PCNA monoclonal antibody. The fibroblasts and epithelial cells in each group contained the immunoreactive products. The den-sity of PCNA positive fibroblasts per unit area was highest in the R group and declined in the ND and NR groups. Statistically significant differences were found between the R and ND groups (p< 0.05), the R and NR groups (p<0.01), and the ND and NR groups (p<0.05), while no significant difference was seen between the NR and Control groups. Likewise, from comparisons of frequency in PCNA positive fibroblasts between highly and poorly cell-infiltrated areas in the connective tis-sues, a significant difference was seen only in gin-gival tissues of the NR group, while there were no differences in the areas of groups R and NR. These findings may suggest the possibility of enhan-cement in proliferative ability of fibroblasts in NF -induced gingival overgrowth, although the number of infiltrated inflammatory cells was not related to that of proliferating fibroblasts.
