Clinical application of customized total temporomandibular joint prosthesis by 3D printing: a five-year follow-up study.

[OBJECTIVES] This study aims to evaluate the clinical efficacy and stability of customized total temporomandibular joint (TMJ) prosthesis by 3D printing from TMJ Yang's prosthesis system after five-years follow-up.

[MATERIALS AND METHODS] This prospective single-center case series study recruited patients required total TMJ prosthesis replacement from March 2016 to September 2022. Patient information was collected and followed up at 1 month, 3 months, 6 months, 1 year, 2 years and 5 years post-surgery. Using CT and panoramic scans to evaluate the prosthesis' position and bone integration. Pain, diet and mandibular function were evaluated by VAS score, and maximum interincisal opening, mouth opening deviation and mandibular maximum forward and lateral movement were recorded. Statistical analyses include descriptive statistics for demographic characteristics and paired t-tests and ANOVA for quantitative analysis.

[RESULTS] 49 consecutive patients with an average age of 52.88 ± 13.78 years were included. The mean follow-up time was 5.00 ± 1.88 years. There were no postoperative infections, and the wound healed well. Patients' postoperative facial shape and occlusion remained unchanged except for one patient improved the facial shape by second-stage genioplasty. The position of the prosthesis was stable and the bone integration was satisfactory. After surgery, pain, mandibular function, and diet improved significantly (P < 0.05) and remained stable 1 year later. The maximum interincisal opening increased (P < 0.05), with mouth opening deviation and movement on the affected side similar to preoperative levels, but movement on the unaffected side and forward movement decreased slightly.

[CONCLUSIONS] The customized total TMJ prosthesis by 3D printing from TMJ Yang's prosthesis system is safe, stable and effective during five years' clinical application.

[CLINICAL RELEVANCE] This study provides a new, safe and effective prosthesis option for temporomandibular joint reconstruction.