BaS analysis: suggesting a new cephalometric model in follow-up of patients with craniostenosis who underwent craniofacial advancement surgery after 1 year from the end of the distraction protocol

Orthodontic-Orthopedic-Surgical Treatment of Syndromic Third Class: Proposal of a New Craniofacial Cephalometric Method

The management of patients suffering from class III due to syndromic craniosynostosis requires a multidisciplinary team to prevent and correct the complex clinical features related to the syndrome. Among the main clinical features, the midface hypoplasia requires surgical advancement with a rigid external distraction device. The comparison of pre- and postdistraction lateral cephalometries is often difficult in these patients, because the craniofacial advancement mobilizes the landmarks routinely used in cephalometry. Aim of this study is to evaluate occlusal, maxillary, and facial changes obtained after the midface osteodistraction using as reference the PM plane, that does not undergo postsurgical spatial modifications.The before and after surgery lateral X-rays of 12 patients were compared to test the cephalometric protocol: 10 angles and 11 linear distances were evaluated.The cephalometric comparison before and after osteodistractions of syndromic class III, using as reference the Enlow's PM plane, has confirmed the data present in current literature, consisting in forward and downward movements of facial middle 3rd, with clockwise rotation of the splanchnocranium and increase of the facial heights. The use of the PM plane as reference could be the solution to problems that have been an obstacle for the study of occlusal and facial changes in patients affected by craniofacial dysostosis.

Corrected Cephalometric Analysis to Determine the Distance and Vector of Distraction Osteogenesis for Syndromic Craniosynostosis

Background:

The purpose of this study was to confirm the utility of a corrected cephalometric analysis to facilitate the planning of distraction osteogenesis with Le Fort III osteotomy for syndromic craniosynostosis.

Methods:

This prospective study involved 4 male and 2 female patients (mean patient age, 8 years 9 months; age range, 4 years 6 months to 13 years 2 months) with Crouzon syndrome who were treated with Le Fort III maxillary distraction using our previously described system of analysis of a corrected cephalogram and who underwent clinical follow-up. Lateral cephalograms were obtained immediately after device removal.

Results:

Distraction of orbitale moved the vector downward to the adult profile, but there was slightly less elongation than the adult profile for the distraction distance. The desired and real mean angles after distraction of point A were 29.2 ± 7.9° and 6.1 ± 8.5°, respectively, and the desired and the real mean distances after distraction of point A were 30.6 ± 12.7 mm and 29.4 ± 4.1 mm, respectively.

Conclusions:

Using the corrected cephalometric analysis, the distance and vector of distraction osteogenesis with Le Fort III osteotomy could be determined in patients with syndromic craniosynostosis. The distraction system brought the patients' facial bones to the planned position using controlling devices.