Orthognathic surgery may affect or cause temporomandibular joint (TMJ) complaints. This study evaluated the need for TMJ surgery after orthognathic surgery.A retrospective cohort study was carried out on 630 consecutive patients undergoing at least a Le Fort I or bilateral sagittal split osteotomy (BSSO). The mean follow-up time was 2,3 years. Clinical, surgical and radiographic findings were collected.Ten of the 630 patients (1.6%) had additional arthroscopic TMJ-surgery in one (9) or in both (1) joints because of internal derangement, resistant to conventional therapy. Only 4/10 patients had successful outcomes following arthroscopic surgery. One patient with unsuccessful outcome required multiple additional open TMJ-surgeries, all remaining ineffective to relieve pain and restricted mouth opening. If arthroscopy failed to relieve symptoms (5/10 patients), further conservative management was opted. Arthroscopy seemed effective mainly in patients without pre-existing TMJ complaints.A further five of the 630 patients (0.8%) required more treatment because of bilateral postoperative condylar resorption, but none of them required TMJ-surgery.In contrast to patients with bilateral condylar resorption where the skeletal relapse remained the issue of concern, patients with internal derangement/osteoarthrosis exhibited major occlusal changes in one patient only (1/10), leaving the TMJ complaints as the main concern. Keywords: Sagittal split osteotomy, Le Fort I osteotomy, Orthognathic surgery, Condylar remodelling, Condylar resorption, Osteoarthrosis, Internal derangement, Relapse, Arthroscopy