Although the research on using platelet-rich plasma (PRP) for temporomandibular joint osteoarthritis (TMJ-OA) has advanced, no unified standards exist for determining the joint use of arthrocentesis and the injection dose and frequency of PRP. This study aimed to compare the efficacy of 2 TMJ-OA treatment approaches, arthrocentesis plus platelet-rich plasma (A+PRP) and PRP alone, and attempted to provide another potential treatment option with a single injection of 2 mL of high-concentration and high-purity PRP.This retrospective matched cohort study enrolled 208 patients who were treated for temporomandibular disorders (TMDs) in the Department of Oral and Maxillofacial Surgery of Tainan Sin-Lau Hospital between August of 2013 and January of 2016, from which 90 patients were selected for the final analysis. The predictor variables were treatment outcome indicators, including joint crepitus sounds, TMD-associated headache, jaw range of motion <6 mm, myofascial pain with referral, temporomandibular joint (TMJ) arthralgia, pain when chewing most foods, and maximum assisted opening (MAO). The data were analyzed using χ tests, t tests, and multiple regression analyses.Among the 90 patients, 30 were assigned into the A+PRP group, and 60 were included in the PRP group. A matching method was used to ensure no statistically significant differences in the categorical and continuous variables between the 2 groups. After treatment, both the A+PRP and PRP groups showed improvements in TMJ-OA. The 2 treatment groups did not show statistically significant differences in the symptom improvement rates of joint crepitus sounds, reparative remodeling, and TMJ arthralgia. However, compared with PRP alone, the A+PRP treatment demonstrated superior performance in improving TMD-associated headache, jaw range of motion <6 mm, myofascial pain with referral, and pain when chewing most foods.Both A+PRP and PRP treatments can effectively improve multiple symptoms of TMJ-OA. Based on the results from this study, we recommend a single injection with 2 mL of high-concentration and high-purity PRP for TMJ-OA treatment. For patients with TMJ-OA accompanied by other clinical symptoms, including TMD-associated headache, jaw range of motion <6 mm, myofascial pain with referral, and pain when chewing most foods, a treatment approach using arthrocentesis prior to a PRP injection can achieve a higher efficacy.