RESUMO
OBJECTIVE: The use of chewing-gum and piercing has become common among adolescents and might result in increased oral muscle activity and overloading. Aim To investigate the frequency of oral piercing and parafunctions in relation to symptoms of temporomandibular disorders (TMD) among adolescents. MATERIALS AND METHODS: One hundred and twenty-four third level high school students, living either in a city or in a small town, enrolled in either science or media programmes, were included. The students completed a questionnaire regarding different parafunctions and symptoms of TMD. A clinical examination of the temporomandibular system and estimation of the tooth wear was performed in 116 students. RESULTS: Chewing-gum was used by 86% of the students (25% with a daily use) and 14% had an oral piercing. The science students used more chewing gum than the media students (p = 0.008), while the media students had more piercings (p < 0.001). Symptoms once a week or more were reported with 39% for headache, 18% for clicking, 7% for facial pain and 6% for difficulty to open wide. Girls reported more headaches (p = 0.007) and more severe symptoms (p = 0.003), had more medical consultations and used more analgesics (both p < 0.05) and had more clinical signs (p = 0.01) than boys. Girls had more oral piercings and used more chewing gum than boys (both p < 0.05). The media students had more sick leave (p < 0.01) than the science students. Chewing-gum use was associated with headache (p < 0.01), with difficulty to open wide (p < 0.05) and with tenderness of the temporomandibular joints and muscles (both p < 0.05). Oral piercing was associated with headache and muscle tenderness (both p < 0.05) and daily nail biting with headache (p < 0.05) and tooth wear (p = 0.004). CONCLUSIONS: There is an association between use of chewing gum, nail biting, oral piercing, and symptoms of TMD.