Oral habits among adolescent girls and their association with symptoms of temporomandibular disorders

Aim: To evaluate the contribution of certain parafunctional activities to the presence of temporomandibular disorder (TMD) symptoms among teenage girls, with special emphasis to gum chewing and jaw play. Methods: A total of 323 girls, aged 15-16 years, were randomly selected from a religious junior high school. The girls responded to a questionnaire on oral habits and TMD symptoms. Results: Gum chewing was a very prevalent habit (62-4%), performed daily (mean chewing time 3-95 h day^-1). Girls who chewed intensively (more than 4 h day^-1) showed associations with pain in the ear area during function and at rest, as well as with joint noises. Jaw play, although reported by only 14.3%, was significantly associated with pain in the ear area during function and at rest, feeling of tiredness of the jaw while chewing, joint noises, catch and lock. All oral parafunctions, except chewing gum, were associated with jaw play and with each other. Conclusions: Jaw play was the most detrimental habit in TMD; intensive gum chewing was a potentially contributing factor for joint noises and pain. Oral parafunctions (except chewing gum) were significantly associated between themselves and suggest a behavioural pattern of 'jaw hyperactivity'.