One-sided gingival hyperplasia after treatment with diphenylhydantoin.

After treatment with diphenylhydantoin for 2 years because of post-infarct focal motor epileptic seizures, a 35-year-old woman was admitted to hospital because of symptoms of intoxication. Almost every sign of the previous left-sided paresis and hypaesthesia had disappeared. A pronounced gingival hyperplasia was found almost exclusively in the left side. The concentration of immunoglobulin A in serum was found far below normal. Admitting that she had not been careful brushing her teeth in the left side because of the strange feeling there (dysaesthesia), the patient had actually carried out a controlled trial proving that she, being predispposed to gingival hyperplasia with a low level of immunoglobulin A in serum, could almost prevent the gingival hyperplasia in the right side by brushing her teeth carefully there.