Description: Dilantin has been used for 50 years to control convulsive disorders. Approximately 50% of those who take it develop fibrous overgrowth of the gingiva. Within 2 weeks to 3 months after initiation of therapy, there is enlargement of the interdental papillae and marginal gingiva. This may progress to the point that the teeth are virtually submerged. Uncomplicated hyperplasia produces a firm pink growth; superimposed gingivitis or periodontitis may cause the gingiva to become boggy and red masking the true nature of the lesion. The anterior gingiva is more severely affected than are posterior and lingual areas. Gingival growth is most pronounced in the first year of therapy. Children and adults under 30 are more susceptible to the condition than are those who are past 30 when treatment begins. Most authors agree that unclean teeth may contribute to the enlargement and scrupulous dental hygiene is required to minimize the inflammatory component of the condition. The term Dilantin hyperplasia is an inappropriate term. Dilantin is the Parke-Davis Company's proprietary name for phenytoin.
Etiology: Phenytoin therapy. As stated above, the condition may become aggravated by superimposed gingivitis and periodontitis. There is evidence that phenytoin may impair the secretion of collagenase by gingival fibroblasts permitting the accumulation of excessive gingival collagen.
Treatment: The inflammatory component may be reduced by good dental hygiene. The fibrous overgrowth requires surgical removal. Discontinuance of phenytoin therapy may result in gradual regression of the overgrowth with i n one year.
Prognosis: Good
Differential diagnosis: Hereditary gingival fibromatosis, hyperplastic gingivitis from dental neglect, leukemic infiltrates of the gingiva, hyperplasia associated with cyclosporin A therapy and calcium channel blockers such as (verapamil [Calan, Isoptin], nifedipine [Procardia], diltiazem [Cardizem])