Mandibular symphyseal distraction osteogenesis: 20 years of experience treating transverse deficiencies with an internal hybrid device

Abstract Introduction Transverse mandibular deficiency has been traditionally managed by orthodontic compensation. However, without resolving the underlying skeletal hypoplasia it leads to high relapse rates. Few studies have reviewed the long-term experience and potential complications of mandibular symphyseal distraction osteogenesis (MSDO) as an alternative treatment method. Materials and method A retrospective review of 20 patients (range: 4–19 years; mean: 11.9 years) treated with a hybrid MSDO device over the period of 1996–2017 was conducted. Epidemiological data, medical and dental history as well as photographic and cephalometric analyses were carried out. Furthermore, pre-operative and long-term post-operative status including dental occlusion and tooth-jaw discrepancies were recorded. Results The distraction amount ranged from 3 mm to 15 mm (mean: 10 mm) with an average distraction period of 30.9 days. In long-term follow-up (mean: 7.3 years), 14 patients presented a class I and 6 patients presented a class II relationship. Correction of overjet, tooth jaw discrepancy and arch length discrepancy were obtained in 18, 20 and 17 cases respectively. A device malfunction was experienced in 6 patients. Conclusion Mandibular widening using a hybrid MSDO device can be efficiently and safely performed in a paediatric population. Further studies confirming our results and analysing facial aesthetic outcomes are warranted.