NIFEDIPINE-INDUCED GINGIVAL OVERGROWTH IN RATS - BRIEF REVIEW AND EXPERIMENTAL-STUDY

The first case report of gingival overgrowth induced by nifedipine (NI F), a calcium-beta blocker, was in 1984. However, the association betw een gingival alterations and the drug therapy of sodium diphenyl hydan toinate was initially described in 1939. The purpose of the experiment al study was to examine the effect of NIF on gingival morphology in an animal model. Forty-five male Sprague-Dawley rats were randomly divid ed into 3 groups. Animals in each group daily received NIF in dimethyl sulfoxide by gastric feeding at a dosage of 0 (control), 30, or 50 mg /kg body weight for 9 weeks. Gingival gross morphology was assessed tr i-weekly from stone models obtained from the mandibular incisal region . Animals were sacrificed at the end of study and tissue blocks were p rocessed for histopathologic and histometric evaluation. Histometric a nalysis was performed at 5 selected tissue levels. Macro-and microscop ic significantly increased gingival dimensions were demonstrated in NI F-treated animals compared to control. Although a fibrovascular tissue was observed in the tooth-gingiva interface for both NIF-treated and control animals, it was thicker and appeared earlier in NIF-treated an imals. The results of the present study suggest that gingival overgrow th can be induced by NIF in rats and that the gingival overgrowth appe ars dose dependent.