Preliminary Study of Standard Artificial Temporomandibular Joint Replacement With Preservation of Muscle Attachment

Purpose: To evaluate the effect of preserving the muscle attachments when performing standard artificial temporomandibular joint replacement (TJR).Patients and Methods: The clinical and radiological imaging data of patients who underwent standard artificial TJR with and without preservation of lateral pterygoid muscle (LPM) and masseter muscle attachments from January 2017 to December 2019 were collected. The maximum interincisal opening (MIO), lateral excursions and protrusion distances, visual analogue scale (VAS) scores of pain, diet, and quality of life (QoL) were recorded before the operation, and 1, 3, 6, and 12 months after the operation. The volumes of LPM and masseter muscles were measured and analyzed by computed tomography (CT) scans.Results: Twenty-seven patients with 36 joints were included in the study. Among them, 11 joints had muscle attachment preserved, and 25 had no muscle attachment preserved. After surgery, the MIO, lateral excursions, and scores of diet, pain, and QoL in the preserved muscle attachment group were significantly better than those in the unpreserved group (P <.05). The measurement volumes of LPM and masseter muscles in the preserved group were significantly larger than that in the unpreserved group (P <.05). Changes of lateral excursion from the TJR side with and without LPM preservation were statistically correlated with the LPM volume (P <.05).Conclusion: Preserving muscle attachment for the standard artificial TJR is beneficial to the recovery of postoperative mandibular function. (C) 2020 American Association of Oral and Maxillofacial Surgeons