Pei Shen1,2,3,4, Dahe Zhang1,2,3,4, Ahmed Abdelrehem5, Shan Jin1,2,3,4, Yi Luo1,2,3,4, Chi Yang6,7,8,9. 1. Department of Oral Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. 2. College of Stomatology, Shanghai Jiao Tong University, Shanghai, China. 3. National Center for Stomatology, Shanghai, China. 4. National Clinical Research Center for Oral Diseases, No. 639, Zhi Zao Ju Road, 200011, Shanghai, China. 5. Department of Craniomaxillofacial and Plastic Surgery, Faculty of Dentistry, Alexandria University, Alexandria, 21563, Egypt. 6. Department of Oral Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. yangchi63@hotmail.com. 7. College of Stomatology, Shanghai Jiao Tong University, Shanghai, China. yangchi63@hotmail.com. 8. National Center for Stomatology, Shanghai, China. yangchi63@hotmail.com. 9. National Clinical Research Center for Oral Diseases, No. 639, Zhi Zao Ju Road, 200011, Shanghai, China. yangchi63@hotmail.com.
Abstract
OBJECTIVES: To investigate the association between sexual maturation and anterior disc displacement (ADD) of temporomandibular joint (TMJ). MATERIALS AND METHODS: Adolescents aged 13-14 years old, attending the first grade of one private junior school, were recruited. Magnetic resonance imaging (MRI) was used to confirm ADD, in addition, the serum levels of sex hormones were tested. Secondary sex characteristics, psychological evaluations, oral health-related behaviors, and sociodemographic characteristics were also collected. RESULTS: A total of 440 teenagers were included, of which the prevalence of ADD was 17.7%. Subgroup analysis revealed that age at menarche in girls and nocturnal emission, laryngeal prominence, voice change, and facial hair in boys showed significant differences between the ADD group and the normal population (all p < 0.05). The serum levels of prolactin in girls (12.23 and 9.82 ng/ml) and testosterone in boys (3.65 and 2.48 ng/dl) were significantly higher in the ADD group compared to the normal population, respectively (both p < 0.05). CONCLUSIONS: This study suggested that sexual maturation has a significant association with ADD both in boys and girls. The increased serum levels of testosterone in boys and prolactin in girls might contribute to the occurrence of TMJ ADD. CLINICAL RELEVANCE: This study provides key data to support and inform longitudinal studies as well as to explain why ADD prefers in adolescents. Main findings can also be used to prevent the occurrence of ADD and secondary jaw deformities.
OBJECTIVES: To investigate the association between sexual maturation and anterior disc displacement (ADD) of temporomandibular joint (TMJ). MATERIALS AND METHODS: Adolescents aged 13-14 years old, attending the first grade of one private junior school, were recruited. Magnetic resonance imaging (MRI) was used to confirm ADD, in addition, the serum levels of sex hormones were tested. Secondary sex characteristics, psychological evaluations, oral health-related behaviors, and sociodemographic characteristics were also collected. RESULTS: A total of 440 teenagers were included, of which the prevalence of ADD was 17.7%. Subgroup analysis revealed that age at menarche in girls and nocturnal emission, laryngeal prominence, voice change, and facial hair in boys showed significant differences between the ADD group and the normal population (all p < 0.05). The serum levels of prolactin in girls (12.23 and 9.82 ng/ml) and testosterone in boys (3.65 and 2.48 ng/dl) were significantly higher in the ADD group compared to the normal population, respectively (both p < 0.05). CONCLUSIONS: This study suggested that sexual maturation has a significant association with ADD both in boys and girls. The increased serum levels of testosterone in boys and prolactin in girls might contribute to the occurrence of TMJ ADD. CLINICAL RELEVANCE: This study provides key data to support and inform longitudinal studies as well as to explain why ADD prefers in adolescents. Main findings can also be used to prevent the occurrence of ADD and secondary jaw deformities.