Orthodontic Treatment and Temporomandibular Joint Condylar Position Relationship with Disk Displacement (Magnetic Resonance Imaging Study)


Temporomandibular joint (TMJ) is a complex synovial articulation between the mandibular condyle and the glenoid fossa of temporal bone. The question of whether a relationship exists between orthodontic treatment, abnormal condyle and disk position, and temporomandibular disorders has been investigated for many years. Despite the abundance of studies, the question continues to trouble orthodontists.This study conducted to assess the relationship between orthodontic treatments, abnormal condyle and disk position, with temporomandibular disorders, and to study the disk- condyle relationship in term of presence or absence of anterior disk displacement. By mean of Magnetic Resonance Imaging a cross sectional investigation for the condyles of temporomandibular joints (TMJs) and disk position was conducted to 50 TMJs of 25 patients between 19-30 years of age who had undergone orthodontic treatment (by upper and lower fixed orthodontic appliances with extraction of maxillary first premolar only for treatment of class II division 1 malocclusion), and 50 TMJs of 25 patients who had not yet received orthodontic treatment from the same class and matched age group.The results of this study showed that 30% of pre-treatment group have anterior disk displacement in comparison to 26.0% of the post treatment group. The condyle position is more concentric in post treatment group than pre-treatment, and the position of the disk is not affected by orthodontic treatment. This conclude that condyle position of the TMJ may be affected by orthodontic treatment, but the disk position is not.