Abstract: Microform cleft lip is the mildest type of cleft lip. Its pathological characteristics are aneretic orbicularis oris muscle and disrupted nasolabial muscle tension line. So the paramount significance of microform cleft lip repair is to rebuild the continuity of orbicularis oris muscle and to reconstruct the nasolabial muscle tension line. Conventional repair of microform cleft lip leads to obvious labial scars, so repair operation has gradually transformed to intraoral approaches. Nowadays, the individualized repair is popular, which should complete the functional correction without obvious labial scars.

Key words: Microform cleft lip, Orbicularis oris muscle, Nasolabial muscle tension line