ORIGINAL PAPER Mandibular alterations and facial lower third asymmetries in unicoronal synostosis Giulio Gasparini & Gianmarco Saponaro & Tito Matteo Marianetti & Gianpiero Tamburrini & Alessandro Moro & Concezio Di Rocco & Sandro Pelo Received: 5 September 2012 / Accepted: 7 December 2012 / Published online: 29 December 2012 # Springer-Verlag Berlin Heidelberg 2012 Abstract Purpose Maxillary and mandibular alterations in children affected by anterior synostotic plagiocephaly have, until today, received only scarce attention. The goal of this paper is to focus on the mandibular alterations, persisting after the early correction of anterior plagiocephaly during the first year of life. Methods Maxillary and mandibular metric measurements were performed on high resolution, thin slices CT scans; all images were reconstructed into 3D models which were used to perform the metrical assessments. Results Twelve patients were selected; all of them had been treated in early age with a neurosurgical interven- tion and had reached the end of maxillo-mandibular growth at the time of the evaluation. Significant dis- crepancies were documented between the two affected sides, with all measured distances being shorter on the synostotic side than the nonsynostotic one, the only exception being the vertical dimension of the mandibu- lar ramus. Discussion Mandibular alterations resulted to be character- ized by lower jaw hypoplasia on the side of the affected suture and anterior displacement of the glenoid fossa; these two entities compensated each other uncompletely, ending in a rotation of the mandibula towards the synostotic side. Keywords Plagiocephaly . Anterior plagiocephaly . Craniostenosis . Mandibular hypoplasia . Facial asymmetry Introduction Anterior synostotic plagiocephaly is a relatively rare form of craniostenosis, 0.4–1/1,000 live births incidence, due to the premature fusion of a half coronal suture. It results in a variable degree of cranial and facial bone asymmetry and distortion which can be distinguished in three main degrees of severity according to the Di Rocco and Velardi classification. The modifications of the frontal and nasal bone as well as those of the skull bones have received great attention, espe- cially when planning the surgical correction, the evaluation of the maxillary and mandibular regions were less deeper investigated. [1–4, 6–12] Generally maxillary and mandibular alterations have been taken into account in late phases of this patholog- ical condition in case they were so important to require additional maxillofacial treatment. The goal of this pa- per is to focus on the mandibular alterations, persisting after the early correction of the anterior plagiocephaly in the first months of life, caused by developmental hypo- plasia of the lower jaw on the side affected by the early fusion of one hemicoronal suture and partially compen- sated by the anterior displacement of the glenoid fossa, occurring during the postoperative facial growth. G. Gasparini (*) : G. Saponaro : T. M. Marianetti : S. Pelo Maxillo Facial Surgery Unit, Complesso Integrato Columbus, Catholic University Medical School, Via Giuseppe Moscati 31-33, 00168 Rome, Italy e-mail: giulio.gasparini@rm.unicatt.it G. Tamburrini : C. Di Rocco Pediatric Neurosurgery, Policlinico Universitario “A. Gemelli”, Catholic University Medical School, Largo A. Gemelli 8, 00168 Rome, Italy A. Moro Maxillo-Facial Surgery, Ospedale “S. Giovanni Battista”, Via Massimo Arcamone, 5-06034 Foligno, PG, Italy Childs Nerv Syst (2013) 29:665–671 DOI 10.1007/s00381-012-2002-7