Distribution by age and sex of functional disturbances and diseases of the stomatognathic system in 7-18 year olds.

The investigation consisted of 749 randomly selected subjects between 7-18 years of age. The subjects were interviewed for symptoms and oral parafunctions and examined clinically for occlusal interferences, malocclusions and signs of functional disturbances and diseases in the stomatognathic system. The group with one or more symptoms indicated no sex difference but the symptoms showed a gradual increase with age. Recurrent headaches were evenly distributed between the ages, but more commonly reported among girls in the age range 7-14 years. Clickings increased by age and some sex differences were found in the age distribution. Grinding and clenching showed a negative correlation with age. Boys reported clenching more often than girls between 7-14 years of age. Lip-cheek-biting and nailbiting were frequently reported in all ages. Girls in the age group of 15-18 years reported lip-cheek-biting more often than boys of the same age group; who on the other hand reported nailbiting more often. A correlation was found between thumbsucking and anterior open bite.