Internal derangement are the most common pathological conditions of the temporomandibular joint. The purpose of this study was to evaluate the success of arthroscopy in the treatment of internal disorders in a Chilean population, considering as parameters the increase in mouth opening and the decrease in pain perceived by the patient, in addition to determining if there were variables that influenced the results. A retrospective cohort study was carried out in which patients who received arthroscopy in one or both joints, performed by the same surgeon, were included. The sample included 67 patients operated on over a period of 2 years and 8 months, with a 1-month follow-up. The average increase in mouth opening at the month of control was 1.42 ± 8.4mm (p value = 0.172), with a relative percentage difference of 0.9 ± 0.3% and a statistically significant decrease in pain was observed in the VAS score. avera- ge (-2 ± 1.5 for the right side and -1.95 ± 1.7 for the left side; p value < 0.001). The pre-intervention pain level was the only variable that was associated with the degree of pain relief after surgery (OR=13.1 right side; OR=6.6 left side).