Consideration of median cleft lip with frenulum labii superior

Median cleft lip is usually divided into true and false when being discussed. Owing to recent developments of diagnostic imaging methods that have improved the accuracy, the presence of an intermediate type of median cleft lip, which cannot simply be divided into true and false, has been suggested. However, the simple method of classification is still clinically valuable. We have previously reported in this Journal a case of median cleft lip with 2 upper labial frenums. In the present study, based on our experience with false median cleft lip, we set forth a hypothesis that 2 upper labial frenums can be found in true median cleft lip, whereas no upper labial frenum is found in false median cleft lip. A review of the results of previous Japanese cases (7 true and 4 false cases) supported our hypothesis. We also reviewed one of our cases of right cleft lip accompanied by holoprosencephaly and discuss the case from the developmental perspective. The shape of the upper labial frenum may be a factor that can be used for clinically classifying intermediate median cleft lip into either true or false in cases that are otherwise difficult to classify.