This study defines a methodological procedure for the design and manufacturing of a prosthetic implant for the reconstruction of a midsagittal bony-deficiency of the skull due to the Apert congenital disorder. Conventional techniques for craniofacial defects reconstruction rely on the mirrored-image technique. When the cranial lesion extends over the midline or in case of bilateral defects, other approaches based on thin plate spline interpolation or constrained anatomical deformation are applied.

The proposed method uses the anthropometric theory of cranial landmarks identification for the retrieval of a template healthy skull, useful as a guide in the successive implant design. Then, anatomical deformation of the region of interest and free-form modelling allow to get the customized shape of the implant. A full bulk and a porous implant have been provided according to the surgeon advises.

The models have been 3D printed for a pre-surgical analysis and further treatment plan. They fulfilled the expectancies of the surgeon thus positive results are predictable.

This methodology results to be reproducible to any other craniofacial defect spanning over the entire skull.

Background: Apert syndrome is one of the craniosynostosis syndromes, with abirth prevalence estimated to be between 9.9 and 15.5/million, and accounts for 4.5 per cent ofcraniosynostoses. Although conductive hearing loss is common in Apert syndrome there are contradicting reports regarding the cause of this hearing loss. There is also no detailed informationavailable on the management of hearing loss in Apert syndrome.

Materials and methods: A retrospective analysis of case notes of Apert syndrome patients seen between 1970 and 2003 at Great Ormond Street Children’s Hospital, London, was undertaken.

Results: Seventy case notes were obtained. The incidence of congenital hearing impairment was between 3 and 6 per cent. Almost all patients had otitis media with effusion (glue ear), which tended to persist into adult life. More than 56 per cent of cases developed permanent conductive hearing loss by 10–20 years. Repeated grommet insertion was common; even though 35 per cent had trouble with ear discharge and persistent conductive hearing loss. Statistically, grommets made no difference to the risk of developing permanent hearing loss.

Conclusion:This study, of the largest number of Apert syndrome cases assembled to date, showed that early optimization of hearing with possible hearing aids needs to be considered. Repeated grommet insertion does not help in optimizing hearing, especially if ear discharge complicates the picture.