Long term results of mandibular distraction

Abstract

Mandibular distraction osteogenesis has become a popular surgical modality due to its many advantages over conventional orthognathic surgical procedures. However, in spite of the technique having been used for over 15 years, no concrete long term results are available regarding the stability of results. We discuss the various studies which have reported either in favour or against the stablility of results after distraction. We report a series of 6 cases (3 unilateral and 3 bilateral distraction) where distraction was carried out before puberty and followed them up to seven years after removal of distractors. This case series shows that results achieved by distraction osteogenesis are unstable or best unpredictable with respect to producing a permanent size increase in the mandible. The role of the distraction osteogenesis in overcoming the pterygomassetric sling is questionable. We suggest a multicenter study with adequate patient numbers treated with a similar protocol and documented after growth cessation to have meaningful conclusions on the debate of distraction osteogenesis versus orthognathic surgery.

Comparison of mandibular vertical growth in hemifacial microsomia patients treated with early distraction or not treated: Follow up till the completion of growth

“…Selecting only the unilateral cases, described in detail in that paper, with a follow-up of more than 3 years: their "return" varied from 51% to more than 100% within 42e92 months of follow-up (data extrapolated from the raw data published by the author). Other papers with 6 and 7 years of follow-up, even though they did not follow patients until the completion of growth, have shown the same tendency (Meazzini et al, 2005;Batra et al, 2006;Gürsoy et al, 2008).…”

Mandibular Distraction in Hemifacial Microsomia Is Not a Permanent Treatment

“…Other articles documenting 6 and 7 years of follow-up, even though they did not follow up patients until the completion of growth, have shown the same tendency. 4,11,12 Given this multisourced but consistent follow-up data, longer patient follow-up might be recommended.…”

No Evidence for Long-Term Effectiveness of Early Osteodistraction in Hemifacial Microsomia ‘Outcomes Article’

“…2,15,17,19,22 One study 13 included three-dimensional measurements and provided quantitative results on volumetric changes of the skeletal and soft-tissue structures. 2,15,17,19,22 One study 13 included three-dimensional measurements and provided quantitative results on volumetric changes of the skeletal and soft-tissue structures.…”

“…15,17,20 The mean number of patients with genuine hemifacial microsomia in the individual studies was 8.8 Ϯ 7.6, varying between 1 and 28. 15,17,20 The mean number of patients with genuine hemifacial microsomia in the individual studies was 8.8 Ϯ 7.6, varying between 1 and 28.…”

“…Three studies did not provide the Pruzansky-Kaban type of the deformity 15,16,23,24 ; three included patients of the same type. 12,17,20 All other studies included a mixed series, with the majority being type IIa ( Table 2).…”