Objective To investigate the effectiveness of modified temporomandibular joint disc reduction and suture with tragus incision assisted by arthroscopy for temporomandibular joint anterior disc displacement (ADD). Methods A clinical data of 30 patients (45 sides) with temporomandibular joint ADD, who met selective criteria and were admitted between September 2022 and February 2024, was retrospectively analyzed. Among them, 15 patients (23 sides) were treated with temporomandibular joint disc reduction and suture via small incision (open operation group), and 15 patients (22 sides) with modified temporomandibular joint disc reduction and suture with tragus incision assisted by arthroscopy (arthroscopy group). There was no significant difference in gender, age, disease duration, affected side, Wilkes-Bronstein stage, preoperative visual analogue scale (VAS) score, maximal interincisal opening (MIO), and temporomandibular joint dysfunction index (DI), craniomandibular index (CMI), palpation index (PI), and other baseline data between groups (P>0.05). VAS score, MIO, and temporomandibular joint function indicators (PI, DI, CMI) of patients were recorded at 3 months after operation, and the difference (change value) of the above indicators between pre- and post-operation was calculated. At 1 week after operation, MRI was performed to evaluate the reduction of the articular disc compared to the preoperative image. The results were classified as excellent, good, and poor, with excellent and good being considered effective reduction. The condition of condyle process repair was observed by cone beam CT (CBCT) at 3 months after operation. Results All incisions healed by first intention in the two groups. All patients were followed up 3-18 months (mean, 8.2 months). Facial nerve injury occurred in 3 cases in the open operation group and 1 case in the arthroscopy group, all of which returned to normal after physiotherapy and drug treatment. At 3 months after operation, MIO and VAS scores of both groups significantly improved when compared with those before operation (P<0.05), and temporomandibular joint function indicators (PI, DI, CMI) significantly decreased (P<0.05). The change values of MIO and temporomandibular joint function indicators in arthroscopy group were significantly higher than those in open operation group (P<0.05). There was no significant difference in the change value of VAS score between groups (P>0.05). There was no recurrence during follow-up. Postoperative MRI review showed that the effective reduction rate of joint disc was 95.65% (22/23) in the open operation group and 95.45% (21/22) in the arthroscopy group, with no significant difference between groups (P>0.05). Postoperative CBCT found that early and timely effective reduction of joint disc was conducive to condyle process repair and reconstruction. Conclusion Modified temporomandibular joint disc reduction and suture with tragus incision assisted by arthroscopy has a clear effect in the treatment of ADD, with less trauma, fewer postoperative complications, and good early effectiveness.