Chapter 37.1, Problem 1QC

Summary Introduction

To determine: The structures that are affected in cleft palate and cleft lip.

Concept introduction: Cleft palate and cleft lip are the most common oral and facial congenital abnormalities. Mostly, these defects take place during the embryonic development. Cleft palate is mostly seen in females, whereas cleft lip with or without cleft palate is more common in males.

Explanation of Solution

Cleft palate is associated with cleft lip. It may also take place without cleft lip. In the cleft palate, the split (cleft) affects only on the uvula and soft palate or may broaden further to the nostril and involve the hard palate and the maxillary alveolar ridge. The teeth present in the cleft palate may be absent or deformed.

Cleft lip occurs due to the incomplete fusion of the nasomedial or intermaxillary process. These processes start during the fourth week of embryonic development. Cleft lip mainly affects the lip. It causes the structures of the mouth and face to develop without the normal restraints of encircling lip muscles. The facial cleft can also affect the nasal cartilages, external nose, nasal septum, and alveolar processes.