Mandible customized distraction osteogenesis in Treacher Collins patient: Literature review, report of a case and post-distraction analysis

Introduction: Treacher-Collins syndrome is a rare genetic disorder with variable phenotypic expression. Related micrognathia can cause upper airway obstruction in neonatal patients because of posterior tongue displacement. Many approaches have been described to treat upper airway obstruction in such patients; the use of mandibular distraction to this purpose was first proposed in 1994. To our knowledge, only a few authors have employed customized devices to perform mandibular distraction in these syndromic patients. This paper presents a systematic review of the use of customized devices to perform mandibular distraction osteogenesis in patients affected by Treacher-Collins syndrome and upper airway obstruction. A case report of a Treacher-Collins syndrome patient treated in our institution is also presented. Results: Eight articles fulfilled the inclusion criteria and were included in this systematic review; demographic, clinical and surgical features of 13 cases were evaluated. Preoperative assessment, virtual surgical planning and a surgical protocol for a Treacher-Collins patient were performed and set-out in detail; a post-distraction 3D analysis workflow was developed and proposed. The patient had an airway obstruction resolution after the distractors removal and was progressively de-cannulated. The post-distraction 3D analysis revealed that the oropharynx and hypopharynx airway space acquired greater volumetric dimension in a more antero-superior position; this advancement was comparable to the antero-superior advancement of the distracted mandible. Conclusion: In the author's opinion, customized devices for mandibular distraction osteogenesis and post-distraction tridimensional analysis should be objected of further investigation in the light of their potential advantage in diagnosis and treatment of syndromic malformation.