A hereditary ectodermal dysplasia of the anhidrotic type is also called the Christ-Siemens-Touraine Syndrome. It is transmitted as an X-linked recessive trait. The typical case of the congenital anomaly is characterized with the triad of the absence of the sweat glands, anodontia, and sparseness of hair. The four-year-old boy affected with the Christ-Siemens-Touraine Syndrome wore a removable appliance. Nine months later, the findings of the dental survey of his masticatory function, were as follows.
1. Poor cooling of the body temperature due to the absence of the sweat glands.
2. Sparseness of the hair of the head and eyebrows.
3. Deformity of the external ear.
4. Congenital missing of _??__??__??_and conical shaped crowns of _??__??__??.
5. Difficulty in chewing.
6. Enhancement of mandibular jaw movement, masticatory muscle activity and masticatory force.