RISK-FACTORS ASSOCIATED WITH TEMPOROMANDIBULAR-JOINT SOUNDS IN CHILDREN 6 TO 12 YEARS OF AGE

The relationship between temporomandibular joint (TMJ) sounds and a pe rson's dental and skeletal characteristics is poorly understood. In th is study, data were obtained from 3428 grade schoolchildren (mean age = 9.0 years, SD = 0.8, range 6 to 12 years), without a history of orth odontic treatment. Each child had been examined independently by one o f six orthodontists to assess: TMJ sounds (none, click, crepitus), gen der, age, race (white/black), skeletal relationships (convexity, maxil lary, and mandibular positions), malocclusion (molar class, overjet, o verbite, anterior crowding, posterior crossbite), maximum opening, chi n trauma (none, cut, scar), and history of lower facial trauma. Tempor omandibular joint sounds were present in 344 children (1 0.0% of the s ample); 276 (8.1%) had an isolated unilateral sound, 254 (7.4%) had un ilateral clicking, 50 (1.5%) had bilateral clicking, 22 (0.6%) had uni lateral crepitus, and 11 (0.3%) had bilateral crepitus. Univariate ana lyses compared children with and without sounds for each variable; log istic regression analyses examined the relationship between groups of variables and TMJ sounds. The prevalence of TMJ sounds was associated with examiner (chi2 = 23.4, df = 5, p < 0.001); increased prevalence o f TMJ sounds occurred in children with maxillary anterior crowding (t = 2.8, p < 0.006), mandibular anterior crowding (t = 3.0, p < 0.002), and increased maximum opening (t = 4.7, p < 0.001). In contrast to oth er reports on children, the prevalence of joint sounds was not associa ted with age, race, gender, or molar class. After accounting for exami ner differences and date of school examination, we concluded that thos e grade schoolchildren with larger maximum opening, increased anterior crowding, and deeper overbites had an increased risk for having a TMJ sound.