Temporomandibular disc direction and shape: a cross-sectional study in adolescents

The aim of this retrospective cross-sectional study was to analyze the temporomandibular joint (TMJ) disc direction and shape among adolescents with temporomandibular disorders (TMD), and to evaluate its relationship with bilateality and with the capacity of reduction in mouth opening, through an evaluation of Magnetic Resonance Imaging (MRI), with the ultimate purpose of preventing the problem and identifying it early in case the pathology is already present in growing patients.MATERIALS AND METHODSBilateral TMJ MRI of 60 adolescents aged between 11 and 18 were evaluated. The sample was divided in two groups, that were and the patients who were under control group comprised of 15 no-The aim of this retrospective retrospectively selected from the pharmacological treatment were TMD patients (9 females and 6cross-sectional study was to ana- institutional database based on excluded from the sample. males) with a mean age oflyze the temporomandibular joint MRI and clinical data availability. In each TMJ, the position and 13.47±1.76 years old. In the(TMJ) disc direction and shape The patients in the control group shape of the disc in the closed study group, 73.3% were fromamong adolescents with temporo- did not present signs and symp- mouth and the reduction capacity the 15-18 age group, while in themandibular disorders (TMD), and toms of TMD and the resonance in the open mouth were evaluat- control group, 66.7% were from to evaluate its relationship with bi- images had been previously re- ed. The Chi2 test was used to per- the 11-14 age group.laterality and with the capacity of quested for ENT reasons, unrelat- form the statistical comparison. In the study group the bilateral reduction in mouth opening, ed to this study. The patients in the The level of significance was es- disc displacement was the most through an evaluation of Magnetic study group were diagnosed with tablished at p <0.05. frequent bilateral disc position Resonance Imaging (MRI), with the intra-articular TMD and MRI of the with anterior direction on bothultimate purpose of preventing the TMJ was prescribed by the treat- RESULTS sides (p = 0.003). When the dis-problem and identifying it early in ing physicians of the patients, to From a population of 102 pa- placement was unilateral the disccase the pathology is already pres- complete the diagnosis and not as tients, 60 adolescents between direction was anterior, there wereent in growing patients. part of this study. 11 and 18 years old who met the no cases of unilateral rotational Patients with systemic disease, inclusion criteria were included. displacement (p = 0.005). MATERIALS AND METHODS craniofacial syndromes or malfor- The study group consisted of 45 In DDwR the most common form Bilateral TMJ MRI of 60 adoles- mations, head and neck neo- patients with TMD (29 females was lengthened (0.035) while in cents aged between 11and 18 plasms, neurological disorders, and 16 males) with a mean age of DDwoR was folded (p = 0.040). In were evaluated. The sample was previous maxillofacial surgeries; 15.73±2.13 years old and the the unilateral displacement, on the side with the normal disc position, the shape of the disc was not biconcave, but itwas lengthened (p = 0.001). CONCLUSIONSBilateral displacement was frequent among adolescents with TMD presenting the same reducon capacity and the same direction of displacement in both TMJ. The anterior displacement was the most common direction associated with the folded disc shape in DDwoR. In patients with unilateral displacement, TMJ with normal disc position presented an alteration of the shape of the disc.CLINICAL SIGNIFICANCEThe results of this study suggest that in adolescent with intra-articular TMD both TMJs are affected together with different degrees of severity. TMD tends to increase with age and may be accompaniedby pain, so it must be detected early.