The effect of a plaque control program on the development of phenytoin-induced gingival overgrowth. A 2-year longitudinal study.

The effect of a plaque control program on the development of phenytoin(PHT)-induced gingival overgrowth was studied in 16 epileptic children, 8-16 years of age during a 2-year longitudinal study. The parameters studied were: visible plaque index (VPI), gingival bleeding index (GBI), probing depth and gingival overgrowth. A preventive program was instituted before the start of the PHT-medication and included oral hygiene instruction and frequent professional tooth cleaning during the observation period. When gingival overgrowth was evaluated on the basis of probing depth, no patients on PHT therapy for 2 years developed pseudopockets (greater than or equal to 4 mm). During the 2-year observation period, there was a statistically significant increase (p less than 0.01) in the thickness of the marginal gingiva bucco-lingually in all patients. This gingival enlargement was already evident (p less than 0.01) after 1 month. The degree of gingival enlargement in this patient group did not increase significantly after the 1st year of PHT-medication and was not significantly correlated to the plasma concentration of PHT. The results of this study show that the development of PHT-induced gingival overgrowth could not be prevented by this specific plaque control program.