**1. Introduction**

Arthroscopy is a technique for direct visual inspection of internal joint structures, including biopsy and other surgical procedures performed under visual control. In 1918 Takagi first described arthroscopy of the knee joint examinations using cystoscope (Tag, 1939). Onishi in 1970 was the first to report arthroscopy of the human temporomandibular joint (TMJ) and the first results were published by him (Onishi*,* 1975, 1980). The progress in research and applications of TMJ arthroscopy in joint disease have led to the acceptance of small operative procedures as a safe, minimally invasive means of effectively treating a number of intra-articular and degenerative TMJ problems (McCain, 1992; Holmlund &Axelsson, 1996; Holmlund et al., 2001). Arthroscopic surgery has been an effective treatment for TMJ disorders refractory to nonsurgical treatments ( Ohnuki et al., 2003*;* Gonzalez-Garcia et al., 2008, Leibur et al., 2010). TMJ arthroscopy has been variously reported as successful in up to 80% of cases where outcome of arthroscopic surgery to the TMJ correlates with the stage of internal derangement (K. Murakami et al., 2000; Sanroman, 2004). Studies have been variable in their scientific method and some long-term outcomes studies have been completed where both quality of life and functional outcome have been assessed (Voog et al., 2003a; Undt et al., 2006; Jagur et al., 2011). For enabling direct comparison of the clinical results following arthroscopic surgery and open surgery a retrospective study comparing two centers´ results using the Jaw Pain and Function Questionnaire ( Clark et al., 1989) has been performed and these treatment results of open surgery were comparable with arthroscopic treatment results (Undt et al., 2006).
