Classification and Anatomy
The cleft or craniofacial anomaly is usually classified during the initial examination of the infant. Craniofacial anomalies, other than clefts, are discussed in Section IV.
- Clefts of the lip and clefts of the palate can occur simultaneously or separately.
- The most common classification system for clefting uses the terms primary and secondary palate to define the cleft.
- The dividing point of the primary and secondary palate is the incisive foramen. The primary palate is anterior to this anatomic point and the secondary palate is posterior to it.
- The primary palate includes:
- Lip
- Alveolus
- The secondary palate includes:
- Hard palate
- Soft palate
- Uvula
- Any cleft of the primary or secondary palate may be complete or incomplete, depending on whether or not the cleft involves the entire anatomic structure.
- Any cleft of the primary or secondary palate may be unilateral or bilateral.
- Submucous clefts of the secondary palate may also occur. These can be detected by visual inspection, ultrasonography or radiography.