Distraction osteogenesis in the management of mandibular hypoplasia secondary to temporomandibular joint ankylosis. Long term follow up

Distraction osteogenesis promotes temporomandibular joint self-remodeling in the treatment of mandibular deviation caused by condylar ankylosis

Craniofacial deformity and malocclusion are primary concerns following temporomandibular joint ankylosis (TMJa) in growing patients, and they pose even greater challenges in adult patients. The treatment objectives always involve restoring proper jawbone structure, achieving stable occlusion, and attaining satisfactory joint mobility. This report presents a 4-year follow-up of an adult patient with TMJa-induced mandibular deviation, who underwent a combined treatment approach involving distraction osteogenesis (DO) and orthodontic-orthognathic surgery. Orthodontic treatment resulted in favorable occlusion and improved facial esthetics. A new condyle with a reconstructed glenoid fossa in a forward position was established after mandibular DO and the damaged TMJ experienced self-remodeling owing to functional improvement. Thus, this case demonstrates the efficacy of DO in promoting adaptive TMJ self-remodeling with long-term stability when treating mandibular deviation caused by condylar ankylosis in adult patients.

Role of Distraction Osteogenesis in the Management of Postankylotic Deformity

INTRODUCTION

Distraction osteogenesis (DO) has evolved in maxillofacial surgery and gained popularity due to the limitations of orthognathic surgery in gross asymmetry cases.

PURPOSE

The primary aim of the paper was to determine if the use of DO for the management of severe deformities of the mandible secondary to temporomandibular joint ankylosis can achieve optimal results, with or without genioplasty, based on cephalometric norms. The secondary aim of this study was to evaluate the complications associated with DO in this group of patients.

MATERIALS AND METHODS

Six patients with postankylotic deformity were included. Both internal and external devices were used for an average mandibular corpus lengthening of 15 mm with adjunctive procedure genioplasty.

RESULTS

All patients had excellent outcome in terms of profile, functional occlusion, and mouth opening without deviation. Two patients had primary genioplasty showed excellent compliance and 2 as secondary at the time of device removal. Complications noted were, difficulty in vector control during distraction, paresthesia, occlusal discrepancy, scarring, and relapse of 2 to 3 mm. Preorthodontics and postorthodontics were done in all patients to settle the occlusion, which was stable after 2-year follow-up.

CONCLUSIONS

Case series shows such gross deformities pose a greater challenge due to undergrowth, gross midline shift, and discrepancy between soft and hard tissue growth pattern and the desired results can be achieved by precise planning. Genioplasty at the time of device placement has definitive positive effect on patient compliance. Though orthognathic surgery has a definitive role in minor deformity, whereas in gross deformities DO with precise planning using 3-dimensional model and vector controlled technique offers excellent outcome.

A systematic review on the outcome of distraction osteogenesis in TMJ ankylosis

Introduction

TMJ ankylosis (TMJa) management by arthroplasty alone fails to address the deformity and the compromised airway. Distraction osteogenesis (DO) can offer a pragmatic solution to TMJa. The aim of the study was to generate evidence towards the role of DO in TMJa, evaluate its efficiency and develop an algorithm for use of DO in TMJa.

Material and methods

The research question was formulated using the PICOS statement for reporting guidelines in systematic reviews, where the efficiency of DO was evaluated in terms of mouth opening, correction of facial deformity and asymmetry, airway correction, and its long term effects.

Results

1130 articles reported DO as a treatment modality for TMJ ankylosis, of which 32 prospective studies, 16 retrospective and 2 RCTs were included in the study. DO was used for mandibular distraction in 45 studies and for simultaneous maxillamandibular distraction in only five studies. An algorithm for use of DO in TMJa was developed.

Conclusion

Although DO has proven its application in TMJ ankylosis cases, its best use is for correction of obstructive sleep apnoea. Relapse causing loss of posterior ramal height is a concern after transport DO. Prearthroplastic DO appears to best correct mandibular deformity. A maxillomandibular deformity requires simultaneous maxillomandibular distraction. However, a metanalysis is still awaited for effectiveness of DO in TMJ ankylosis.

Digitally designed, personalized bone cement spacer for staged TMJ and mandibular reconstruction - Introduction of a new technique

The aim of this paper is to introduce an innovative workflow for staged reconstruction of the mandible, including the temporomandibular joint (TMJ), using a temporary, patient-specific spacer. In cases of partial mandibular resection including disarticulation, sometimes needed to treat inflammatory bone disease, the spacer is intended to retain symmetry of the hard tissues, to preserve the soft tissues, and to act as a bactericidal agent. When complete healing of the affected surrounding tissues has occurred, final reconstruction using a patient-matched total TMJ endoprosthesis, in combination with an autogenous free bone flap, can be performed as a second-stage procedure. The crucial steps of the workflow are virtual surgical planning, manufacturing of a two-part silicone mold, and chairside manufacturing of the spacer using an established bone cement with gentamycin. The method was first introduced in two patients suffering from therapy-resistant chronic osteomyelitis. The presented protocol of staged surgery allows a much safer and predictable reconstruction compared with immediate reconstruction. The workflow also minimizes the potential risk of endoprosthesis infection - one of the major risks of implant failure.

Distraction Osteogenesis Plus Permanent Rigid Fixation for Mandibular Deformities in Nongrowing Patients: A Comparative Study

ABSTRACT

Distraction osteogenesis (DO) is a commonly used intervention of mandibular deformities. However, relapse of the newly constructed mandible is a significant concern. The present comparative study aimed to investigate use of rigid fixation in addition to DO in management of mandibular deformities. The present study included 20 patients with mandibular deformities indicated for DO. The study comprised 10 patients who agreed to perform rigid fixation (DO + RF) and other 10 patients who refused to perform the additional procedure (DO). All patients were subjected to standard mandibular DO. In patients subjected to additional RF with plate and screws, on the last day of distraction, the distractor is removed in the theatre under general anesthesia. Then by an intraoral incision on the previous scar, the distracted part is explored and the plate is applied in the lower part of the mandible to avoid destruction of the teeth roots. All patients are subjected to close observation and radiological evaluation for the appearance of any complication, signs of relapse at the intervals of 1 week and 6 months and 1 year. At the end of follow-up, 2 patients in the DO + RF group relapsed while all patients in the DO only group relapsed (P < 0.001). The relapsed distance was significantly greater in the DO group [(median (range): 0.3 (0.1-1.3) versus 0.0 (0.0-0.2), P ≤ 0.001]. DO + RF provided significantly lower rate and distance of relapse in nongrowing patients with mandibular deformities.

Controversies in the management of temporomandibular joint ankylosis using distraction osteogenesis - A systematic review

Background:

The three commonly employed sequences of distraction osteogenesis (DO) in the management of temporomandibular joint (TMJ) ankylosis with dentofacial deformities include post-arthroplastic distraction osteogenesis (PAD), simultaneous arthroplastic distraction osteogenesis (SAD), and pre-arthroplastic distraction osteogenesis (PrAD).

Objective:

The aim of this systematic review is to compare the effectiveness of various sequences of DO in the management of TMJ ankylosis with micrognathia/and obstructive sleep apnea syndrome (OSAS).

Data Sources:

A comprehensive online and manual search of English language literature with no date restrictions was done on March 2020.

Eligibility Criteria:

Inclusion criteria were case series and prospective and retrospective studies involving adult/paediatric human subjects with unilateral/bilateral TMJ ankylosis and micrognathia/OSAS treated with DO.

Study Appraisal and Synthesis Methods:

Of 73 studies identified, only 10 were included in the qualitative synthesis. The outcomes assessed were as follows: maximum mouth opening (MMO), posterior airway space (PAS), polysomnography variables, reankylosis, mandibular length, and chin and mandible position.

Results:

All the included studies showed high risk of bias. MMO and mandibular length increased, chin and mandibular position improved by the end of treatment in all the three sequences, and polysomnography variables and PAS significantly improved in PrAD compared to PAD and improved in SAD compared to baseline. Reankylosis was significantly less in PrAD.

Conclusion:

More well-designed studies comparing the three sequences of DO should be carried out to arrive at a consensus.