Modified internal mandibular distraction osteogenesis in the treatment of micrognathia secondary to temporomandibular joint ankylosis: 4-Year follow-up of a case

A systematic review of the clinical outcomes for various orthodontic and physiotherapy appliances used for the management of temporomandibular joint ankylosis

Ankylosis of the temporomandibular joint (TMJ) is associated with restricted mandibular movements, with deviation to the affected side. The management of TMJ ankylosis involves surgery to mitigate the effects of ankylosis, and adjunctive appliance therapy to supplement the results achieved through surgery. Several appliances have been used to help maintain jaw mobility postsurgery, but have been rarely documented in the literature. Our systematic review aimed to examine the clinical outcomes of various appliances for TMJ ankylosis management. A comprehensive electronic search of the literature was performed in July 2022 to identify eligible articles that had tested the use of orthodontic or physiotherapy appliances for the management of TMJ ankylosis. In total, 13 publications were included in the narrative synthesis. Both generic and custom-made appliances were used, with overall findings suggesting that using these appliances improved mouth opening and reduced chances of re-ankylosis. In this review no universally accepted appliance was found to be utilized, and the criteria used for appliance selection were unclear. The field of research in developing appliances for the treatment of TMJ ankylosis is open to advancement, and this review will help guide future research in this area.

Changes in occlusal relationships observed using an intraoral scanner in patients with an acquired open bite: A case report

PATIENTS

This case report describes a procedure for assessing changes in occlusal relationships in patients with acquired open bites due to temporomandibular joint disease using an intraoral scanner (IOS). A digital impression was made using the IOS at the initial visit. Subsequent impressions were made every 6 months using the IOS and magnetic resonance imaging (MRI) or computed tomography (CT). Standard triangulated language (STL) image files of two digital impressions at different points in time were superimposed, including the occlusal relationship with reference to the maxillary dentition. Finally, three-dimensional (3D) changes in the occlusal relationship over time were evaluated.

DISCUSSION

In Case 1, the superimposed STL image indicated almost no evident deviation of the mandible. Therefore, an orthodontic treatment was initiated. In contrast, in cases 2 and 3, where changes in the occlusal relationship continued, secondary treatment was postponed and patients continued to be monitored periodically. In case 3, even though left condyle resorption was progressive, the degree of open bite on the right side improved after 6 months. However, the open bite continued to progress for another 6 months despite the stability of the condyle.

CONCLUSIONS

Changes in the condylar shape observed using imaging may not always reflect changes in the occlusal relationship. In addition to changes in the condyles and eminences of the temporomandibular joint (TMJ), changes in the occlusal relationships of patients with acquired open bite should be evaluated using an intraoral scanner.

Arthroplasty Followed by Distraction Osteogenesis Versus Distraction Osteogenesis Followed by Arthroplasty in the Management of TMJ Ankylosis: A Comparative Study

Aim

To compare treatment outcome of arthroplasty followed by distraction osteogenesis (AFD) and distraction osteogenesis followed by arthroplasty (DFA) in the management of mandibular deficiencies in temporomandibular joint (TMJ) ankylosis.

Materials and methods

A total of 20 patients with TMJ Ankylosis were included in the study. Patients were randomly divided into two groups. Group 1 consisted of patients for whom arthroplasty was done prior to distraction osteogenesis (AFD) for the correction of deficient mandible. Group 2 included patients where distraction osteogenesis was performed prior to arthroplasty (DFA). The treatment outcome was assessed based on maximum interincisal distance, overjet, corpus length, ramus height, upper airway, lower airway, duration of the procedure and the complications for the treatment at the end of 3, 6 and 12 months.

Results

After the treatment was ended, the patients of both groups had increase in mouth opening and appearance was improved remarkably. There was general increase in all the parameters in both the groups. But at the end of 12 months, airway and the ramus height were more stable and the control of the proximal segment was superior in DFA group. Open bite was noticed in 2 cases of AFD group which was treated by elastics. There required additional surgery for the removal of distractors in the AFD Group. Establishing the airway during the surgery was easier in AFD group.

Conclusion

The study concludes that distraction followed by arthroplasty was a better procedure for the management of TMJ ankylosis owing to its stable results and less number of surgeries.

Formation of Condyle-Like Structure after Treatment of Temporomandibular Joint Ankylosis: Literature Review and Long-Term Follow-Up of Two Patients

Treatment of ankylosis is one of the greatest challenges in temporomandibular joint (TMJ) surgery. To provide a satisfactory mouth opening, as well as normal jaw function, and to prevent reankylosis in the long term are the most important principles in the treatment of TMJ ankylosis. These functions have been attained in both of the presented patients in the long term. It is known that heterotopic bone formation is rare in the maxillofacial area, but rapid bone regeneration which reconstitutes a new condyle is rarer. The purpose of the presented paper is to reveal the existence of an inherent capability of the mandible, rapid bone growth of the ramus mandible, and reformation of a previously nonexisting condyle after resection of the ramus in patients with TMJ ankylosis. In this paper, two unusual cases of unexpected condyle-like structure formation after treatment of ankylosis were presented.

A novel step osteotomy for correction of hemifacial microsomia - A case report

Facial asymmetry is one of the commonest facial anomalies, with reported incidence as high as 34%. Hemifacial microsomia (HFM) has an incidence of 1 in every 4000-5600 children and is one of the commonest causes of facial asymmetry. The standard treatment of HFM is orthognathic surgery by bilateral saggital split osteotomy (BSSO) or distraction osteogenesis (DO) of the mandible, both of which involve prolonged periods of occlusal adjustments by an orthodontist. Here, we present distraction of the mandible by means of a novel modified step osteotomy to correct the facial asymmetry in a case of hemifacial microsomia without disturbing the occlusion. This novel technique can prove to be a new tool in the maxillofacial surgeons armamentarium to treat facial asymmetry.

Simultaneous gap arthroplasty and intraoral distraction and secondary contouring surgery for unilateral temporomandibular joint ankylosis

Background

Temporomandibular joint (TMJ) ankylosis can be accompanied by various degrees of functional and esthetic problems. Adequate mouth opening, occlusal stability, and harmonious facial form are the main goals of treatment for ankylosis. Distraction osteogenesis has proven to be an excellent treatment for lengthening the ramus-condyle unit. However, various timings for distraction have been suggested, and there is no consensus on selection criteria for performing the procedure in stages or simultaneously with other treatments.

Case presentation

In this case report, concomitant intraoral distraction and gap arthroplasty was planned to treat TMJ ankylosis and associated facial asymmetry. After gap arthroplasty and 23 mm of distraction, the ramus-condyle segment was successfully lengthened and mouth opening range was significantly increased. The resultant interocclusal space was stably maintained with an occlusal splint for 4 months after distraction. Finally, good occlusion was achieved after prosthetic treatment. The remaining mandibular asymmetry was corrected with osseous contouring and augmentation surgery. The mouth-opening range was maintained at 35 mm 24 months after treatment.

Conclusion

Gap arthroplasty with intraoral distraction as a one-stage treatment and subsequent contouring surgery can be applied to correct ankylosis with moderate malocclusion and facial asymmetry.

Distraction osteogenesis for correction of post ankylosis mandibular deformities

Temporomandibular joint ankylosis, a debilitating disease mainly affecting children, is characterized by progressive restriction of mouth opening and maxilla-mandibular developmental deformities. Craniofacial distraction osteogenesis has been developed as a standard surgical strategy for rectification of craniofacial deformities. The purpose of this study was to assess mono-planar distraction devices for the correction of various mandibular asymmetries in patients with unilateral temporomandibular joint ankylosis who developed restricted mouth opening and mandibular retrognathia. All patients were treated using one-stage distraction osteogenesis followed by temporalis fascia interpositional arthroplasty under general anesthesia. A significant increase in mandibular ramus and base length was observed. Although an increase in anterior lower facial height was observed, it was not significant statistically. A decrease in posterior lower facial height and corpus was observed. Oblique distraction with angular osteotomy allowed lengthening of both the ramus and corpus, yielding satisfactory results and hence eliminating the need of secondary surgery. In conclusion, univector internal distractors are effective for correction of multi-planar mandibular deficiencies by optimizing its placement through meticulous planning.

Osteodistraction of mandibles with a small bone defect at the planned osteotomy site: a histological pilot study in dogs

AIM

To develop a treatment plan for cases in which a bone defect is located on the osteotomy line of mandibular osteodistraction (DO).

SUBJECTS AND METHODS

Bilateral DO was performed in 17 Mongrel dogs. Prior to surgery, the 34 hemi-mandibles were randomly allocated to three groups: C (n = 10; a standard DO was performed), D - G (n = 12; a bone defect was created on the DO osteotomy line), and D + G (n = 12; the bone defect on the osteotomy line was grafted). After one week of latency, 8 days of distraction, and 4 weeks of consolidation the animals were sacrificed, and the newly formed bone were examined.

RESULTS

In group C, two zones of immature trabecular bone originating from host bone margins were separated by a central fibrous zone. In group D + G uniform new bone formation of the entire distraction gap was observed. In group D - G the distraction gap was mainly filled with fibrous tissue. The values for the newly formed bone volume and trabecular thickness were not significantly different between groups D + G and C, but were higher than values in group D - G (p < 0.05).

CONCLUSION

When a mandibular defect is located at the site of distraction osteotomy, DO can be performed simultaneous with bone grafting of the defect.