Does Mandibular Distraction Vector Influence the Rate of Temporomandibular Joint Ankylosis?

Implications of Distraction Osteogenesis in Ankylosis of Temporomandibular Joint

“…6 Therefore, it can be considered unlikely that the forces generated by the distraction process are high to generate harmful effects on human TMJs. 6,7 In her work Xiao (2019) addresses a theory about this difference which is related to the distraction vector; a vertical vector is more likely to lead to TMJ ankylosis because of the cranially driven pressure supported by TMJ during activation, in comparison with the horizontal or obliquely directed vector, the objective of this study was to retrospectively evaluate the medical records of patients submitted to mandibular distraction at the Children's Mercy Hospital from 1997 to 2015. All the operations were performed by 3 surgeons.…”

“…The authors concluded that vertical mandibular distraction carries a significantly increased risk of TMJ ankylosis and should be avoided. 9 The Nager syndrome, also known as the acrofacial dysostosis of Nager, patients usually have micrognathia, and a preventive tracheostomy is necessary when there are symptoms of upper airway obstruction. 10,11 In the study by Wu and collaborators the authors reported two patients with Nager syndrome suffering from TMJ ankylosis after mandibular distraction osteogenesis the authors state that multiple factors are related to ankylosis of the temporomandibular joints after mandibular distraction osteogenesis in patients with Nager syndrome.…”

“…Micrognathia, if not resolved, results in malocclusion, which may cause difficulties in feeding, dysfunction of the temporomandibular joint and aesthetic dissatisfaction, the main treatment of this disorder being distraction osteogenesis with the objective of performing the mandibular stretching. 9,10 The main cause of ankylosis is trauma, followed by local or systemic infection, such as ankylosing spondylitis and rheumatoid arthritis. Ankylosis can also be a result of a mandibular distraction surgery that was not successful.…”

“…Ankylosis can also be a result of a mandibular distraction surgery that was not successful. 4,9 The objective of this study was to verify in the literature the relationship between distraction osteogenesis and the ankylosis development of temporomandibular joint.…”

Management of Bilateral Temporomandibular Joint Ankylosis and Class 2 Malocclusion in a Patient With Nager Syndrome

“…When compared to oblique and horizontal advancements of the mandible, vertical distraction of the ramus-condyle unit into the glenoid fossa has been shown to greatly increase the risk of developing TMJ ankylosis with one study observing that 17% of patients developed osseous ankylosis postoperatively. 20 Craniomaxillofacial surgeons may also employ condylar offloading techniques during the procedure in order to minimize the force imposed on the TMJ apparatus. 12,21-23 Offloading devices have been demonstrated to be highly efficacious for preventing the development of TMJ ankylosis following MDO particularly when treating syndromic patients who often present with pre-existing TMJ disease.…”