Fibrous condylar dysplasia: Resection and reconstruction with a custom-made TMJ prosthesis using virtual surgical planning

Patient specific total temporomandibular joint reconstruction: A review of biomaterial, designs, fabrication and outcomes

Purpose

The aim of this article was to systematically review the available literature on patient specific total temporomandibular joint total joint replacement (PS-TMJR) implants for their biomaterial, designs, fabrication techniques and their outcomes.

Methods

A literature review was conducted using PubMed, and science direct databases using the key words three-dimensional printing, 3D printing, CAD CAM, computer aided designing, computer aided manufacturing, additive technology, custom made implants, patient specific implants in combination with Temporomandibular joint, TMJ surgery.

Results

The search revealed 2760 articles, of which 374 were in English and discussed TMJ reconstruction. Further filtering shortlisted 74 articles that discussed PS-TMJR. Duplicates were removed and additional added from article references. 39 articles describing biomaterial, designing and fabrication of PS-TMJR implants and their outcomes were selected for analysis.

Conclusions

Although PS-TMJR implants allow a better anatomical fit, improved fixation, and safeguard various structures such as the inferior alveolar nerve, they vary in designs, material and fabrication techniques. However, PS-TMJR printed with SLM and EBM technologies have yet to be compared with the conventional ones in terms of mechanical strength, and clinical outcome. With emerging bioprinting technologies, even newer biomaterials should be considered for 3D printing of PS-TMJR devices designed to achieve harmony in function between the joint device, bone and masticatory muscles.

Impact of technology in temporomandibular joint reconstruction surgeries: A systematic review

OBJECTIVES

The digital technologies, in recent years, have integrated with temporomandibular joint reconstruction surgeries (TRS). Therefore, a systematic study was conducted to assess the impact of digital technologies in TRS. Besides, a brief comparison between the CAD/CAM and 3D printing (3DP) technologies is presented.

MATERIALS & METHODS

We searched in PubMed, ProQuest and Science direct using PRISMA guidelines. Population = Patients undergoing TRS, Intervention=CAD/CAM or 3DP, Comparison= conventional TRS (cTRS) vs technology integrated TRS (tiTRS), Outcome= Advantages/disadvantages of technology and Subjective/objective symptoms, Study design= Type of study. The quality of observational study was assessed using ROBINS-1 Assessment tool.

RESULTS

Out of 632 articles, 30 articles for CAD/CAM and 3DP were included in the study. A majority of TRS were done for ankylosis (new or re-entry), earlier failed surgery, osteoarthritis and neoplastic cases. The articles were divided into two groups. Group I: CAD/CAM(n = 16), Group II: 3DP (n = 14).

DISCUSSION

tiTRS had definite advantages over cTRS with lesser surgery time, defined osteotomies, précised implant fitting and better final result outcome however, evidence for tiTRS in long-term follow-up is inconclusive. The cost, time, infrastructure and ethical/regulatory issues are the downsides of assisted surgeries. It was observed that 3DP technology is versatile and its adaptation in the fabrication of customized implants has outpaced CAD/CAM technology. However, literature data is feeble qualitatively and quantitatively.

CONCLUSION

The TRS has leveraged the flexibility and precision of assisted surgeries. In future, tiTRS could successfully replace cTRS, provided that shortcomings should be dealt so that the technology can benefit the masses.

Use of CAD-CAM Bridging Mandibular Prosthesis in Osteonecrosis of the Jaw: The Experience of Our School

Osteonecrosis of the jaw (ONJ) is a disease that affects the jaw. It is mainly related to radiation or bisphosphonates therapy, and the symptoms and signs consist of pain, bone exposure, inflammation of the surrounding soft tissue swelling, and secondary infection or drainage. In the case of advanced disease of the mandibular area, the treatment of choice is mandibular resection and reconstruction. In the present study, we report a case series of patients affected by ONJ and treated with a customised bridging mandibular prosthesis-only technique. From 2016 to 2018, we treated five consecutive patients affected by ONJ: three patients were affected by biphosphonate-related osteonecrosis of the mandible (BRONJ) and two were affected by osteoradionecrosis of the mandible (ORNJ). Three patients needed a soft tissue free flap to permit optimal wound closure, intra- and/or extraorally. All reconstructive procedures were carried out successfully, with no major or minor microvascular complication. The average postoperative follow-up was 24.8 (range 10–41) months. Considering that microvascular bone transfer is a high-risk procedure in BRONJ patients, we can conclude that the positioning of a customised bridging mandibular prosthesis (CBMP), whether or not associated with a microvascular soft tissue transfer, is a safe technique in terms of surgical outcome and feasibility.