Keratocyst recurrences at intervals of more than 10 years: case reports.

The two cases reported here are of keratocysts which recurred after exceptionally long intervals. In the first case, the keratocyst recurred twice during the 37-year follow-up: 16 years after the initial operation and 21 years after the second. In the second case the recurrence occurred 14 years after surgical treatment. Recommendations for the duration of follow-up are discussed.