Autogenous Reconstructive Modalities of TMJ Ankylosis-A Retrospective Analysis of 45 Cases

Autogenous grafts for reconstruction arthroplasty in temporomandibular joint ankylosis: A systematic review and meta-analysis

Autogenous methods for reconstruction arthroplasty (RA) for the surgical management of the temporomandibular joint (TMJ) have been extensively reported. The present review was aimed to systematically review and pool data on clinical outcomes of autogenous grafts for RA in subjects with TMJ ankylosis. Major electronic databases and prominent subject-specific journals were searched up to December 2020. Randomised controlled trials (RCT), cohort studies, and retrospective studies reporting outcomes of autogenous grafts for RA in TMJ ankylosis were included. A total of 35 studies with 700 subjects was included. The most commonly employed grafts were costochondral grafts (CCG) and coronoid process grafts. Postoperative change in maximum incisor opening (MIO) was comparable amongst all grafts and was in the clinically acceptable range (27.21-31.38 mm). The recurrence rate was comparable for all grafts and was ≈ 8% except for coronoid grafts, where the recurrence rate was 2.98%. Growth assessment for CCG revealed that 55.89%, 30.89%, and 13.24% of subjects depicted optimal growth, overgrowth, and undergrowth, respectively. Within the limitations of the present review, the recurrence rate for all grafts was comparable except for coronoid graft, which depicted least recurrence rate and resultant postoperative change in MIO was in the clinically acceptable range.

Biomechanical analysis of costochondral graft fracture in temporomandibular joint replacement

This study is the first attempt to explore the reason of costochondral graft fracture after lengthy mandible advancement and bilateral coronoidectomy by combining finite element analysis and mechanical test. Eleven groups of models were established to simulate costochondral graft reconstruction in different degrees of mandible advancement, ranging from 0 to 20 mm, in 2 mm increment. Force and stress distribution in the rib-cartilage area were analyzed by finite element analysis. Mechanical test was used to evaluate the resistance of the rib-cartilage complex. Results showed a sharp increase in horizontal force between 8 and 10 mm mandible advancement, from 26.7 to 196.7 N in the left side, and continue increased after 10 mm, which was beyond bone-cartilage junction resistance according to mechanical test. Therefore, we concluded that bilateral reconstruction with coronoidectomy for lengthy mandible advancement (≥ 10 mm) may lead to prominent increase in shear force and result in a costal-cartilage junction fracture, in this situation, alloplastic prosthesis could be a better choice. We also suggested that coronoidectomy should be carefully considered unless necessary.

Functional Reconstruction of Temporomandibular Joint after Resection of Pigmented Villonodular Synovitis with Extension to Infratemporal Fossa and Skull Base: A Case Report

Introduction  Pigmented villonodular synovitis (PVNS) is a benign but aggressive lesion arising from sinovia. The temporomandibular joint (TMJ) is hardly ever involved.

Methods  We describe a case of PVNS arising in the left TMJ involving infratemporal fossa soft tissue and the skull base; we also present the reconstruction.

Results  A 37-year-old woman had progressive mandibular swelling for 6 months. Computed tomography of the skull revealed an osteolytic lesion in the left TMJ, involving the upper mandible, condyle, and glenoid fossa and extending to the infratemporal fossa and fossa media through a defect in temporal bone. Surgical management included a left pterional craniotomy to reach the temporal skull base and resect the intracranial tumor and a facial approach with partial left mandibulectomy and resection of left condyle, glenoid fossa, and tumor removal in infratemporal fossa. Mandible function was restored with prosthetic reconstruction of the condyle. She progressively started to eat solid foods after 3 months, becoming increasingly functional and asymptomatic. At 30 months' follow-up, she had no sign of tumoral recurrence and showed asymptomatic and normal TMJ function.

Conclusion  PVNS should be considered in the differential diagnosis of bone neoplasms affecting young patients. In such cases, radical excision is mandatory and TMJ prosthesis for local reconstruction may be used to preserve functionality.

Potential Indications for Tissue Engineering in Temporomandibular Joint Surgery

PURPOSE

Musculoskeletal tissue engineering has advanced to the stage where it has the capability to engineer temporomandibular joint (TMJ) anatomic components. Unfortunately, there is a paucity of literature identifying specific indications for the use of TMJ tissue engineering solutions. The objective of this study was to establish an initial set of indications and contraindications for the use of engineered tissues for replacement of TMJ anatomic components.

FINDINGS

There was consensus among the authors that the management of patients requiring TMJ reconstruction as the result of 1) irreparable condylar trauma, 2) developmental or acquired TMJ pathology in skeletally immature patients, 3) hyperplasia, and 4) documented metal hypersensitivities could be indications for bioengineered condyle and ramus TMJ components. There was consensus that Wilkes stage III internal derangement might be an indication for use of a bioengineered TMJ disc or possibly even a disc-like bioengineered "fossa liner." However, there was some controversy as to whether TMJ arthritic disease (e.g., osteoarthritis) and reconstruction after failed alloplastic devices should be indications. Further research is required to determine whether tissue-engineered TMJ components could be a viable option for such cases. Contraindications for the use of bioengineered TMJ components could include patients with TMJ disorders and multiple failed surgeries, parafunctional oral habits, persistent TMJ infection, TMJ rheumatoid arthritis, and ankylosis unless the underlying pathology can be resolved.

CONCLUSIONS

Biomedical engineers must appreciate the specific indications that might warrant TMJ bioengineered structures, so that they avoid developing technologies in search of problems that might not exist for patients and clinicians. Instead, they should focus on identifying and understanding the problems that need resolution and then tailor technologies to address those specific situations. The aforementioned indications and contraindications are designed to serve as a guide to the next generation of tissue engineers in their strategic development of technologies to address specific clinical issues.