Evaluation of effusion and articular disc positioning after two different arthrocentesis techniques in patients with temporomandibular joint disc displacement without reduction.

OBJECTIVE: To evaluate joint effusion and positioning of the articular disc through magnetic resonance imaging (MRI) before and after two different arthrocentesis techniques. METHODS: Twenty-six patients with dislocation of the articular disc without reduction (ADDwoR) were included and randomly divided into two groups: single needle arthrocentesis with distention of the upper compartment of the TMJ (A1) and conventional arthrocentesis with 2 needles (A2). RESULTS: A statistically significant difference was observed between the different effusion categories (p = 0.009). No differences were found comparing both treatment modalities concerning the position of the mandibular condyle and the articular disc. CONCLUSION: Conventional arthrocentesis was able to change the effusion variable, whereas the single needle arthrocentesis was not. Both techniques were responsible for altering the position of the mandibular head or the disc-head complex, projecting them to a more anterior position related to the increase in the final maximum interincisal distance.