TMD is an umbrella term that refers to a variety of clinical conditions involving the masticatory muscle, the temporomandibular joint (TMJ), and adjacent structures (Hentschel et al., 2005).

Some authors believe that internal derangement of the TMJ is the result of lateral pterygoid muscle hyperactivity or hypoactivity, poor coordination between its two heads, a disturbance in the normal role of the muscle in the control or stabilization of the TMJ (Mehndiratta et al., 2019).

Indeed, numerous surgical and conservative treatments have centered on repositioning or recapturing the disc over the last 35 years, including mouth repositioning devices, mandibular manipulation, and disc repositioning operations (Goncalves et al., 2015).

Different arthroscopic procedures and surgical instruments have been reported for the treatment of internal derangement of TMJ. Of interest are those dedicated explicitly to the repositioning of the disc, myotomy of lateral pterygoid, and scarification of retrodiscal tissue in cases with anterior disc displacement without reduction or chronic closed lock. However, clinical improvements concerning mouth opening might be due to disc repositioning over the condyle or the disc complex's increased mobility. In practice, the decision to operate and the choice of the method seems to be a matter of the individual surgeon's training, experience, and attitude toward the arthroscopic-assisted management of TMJ disorders (Sanders, 1986).

Based on these facts, the purpose of this study was to compare arthroscopic-assisted release of lateral pterygoid contrary to scarification of retrodiscal tissues in the treatment of TMJ internal derangement.