Clinical Paper Orthognathic Surgery Facial soft tissue changes after transverse palatal distraction in adult patients G. A. Ramieri, A. Nasi, A. Dell’Acqua, L. Verze ´: Facial soft tissue changes after transverse palatal distraction in adult patients. Int. J. Oral Maxillofac. Surg. 2008; 37: 810–818. # 2008 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. G. A. Ramieri 1 , A. Nasi 1 , A. Dell’Acqua 1 , L. Verze ´ 2 1 Department of Maxillofacial Surgery, University of Turin, Italy; 2 Department of Anatomy, University of Turin, Italy Abstract. This longitudinal study investigated the 3-D facial soft-tissue response to transverse palatal bone-anchored osteodistraction in 18 adult patients. Laser- scanned facial surface data were obtained for all patients before (T 0 ), 6 months (T 1 ) and 1 year (T 2 ) after transverse palatal distraction. The averaged facial morphologies at T 0 ,T 1 and T 2 were calculated and compared. Sagittal and vertical measurements were obtained from lateral cephalograms to evaluate skeletal and dental movements. Pre- and immediate post-distraction dental casts were used to investigate transverse maxillary movements. Cutaneous changes were mainly observed in the paranasal regions and cheeks, in the range 1–3 mm, reflecting the underlying increase in the maxillary width. A significant enlargement of the nasal base was also demonstrated. The absolute magnitude of these facial changes was limited but clinically relevant. Variable skeletal movements were observed. These were of low magnitude and no systematic tendency could be demonstrated statistically. Significant changes were documented only with regard to orthodontic repositioning of the upper and lower incisors. The mean transverse increases in the maxillary dental arch were 6.7 mm at the intercanine, 6.8 mm at the interpremolar, and 6.1 mm at the intermolar levels. Keywords: 3-D imaging; facial changes; orthognathic surgery; trans-palatal distraction. Accepted for publication 2 May 2008 Available online 25 June 2008 Surgically assisted rapid maxillary expan- sion (SARME) is frequently required in late adolescent or adult patients to correct a transverse inter-arch discrepancy or to resolve crowding without tooth extrac- tion 4,21,29,30,39 . This surgical treatment may be isolated or associated with subse- quent jaw repositioning to correct major vertical or sagittal anomalies. Recently, transverse palatal distraction (TPD) has been proposed as a refinement of the method, which should reduce skeletal relapse and periodontal side effects of treatment 12,24,32 . While many studies have evaluated dental and periodontal effects or the ske- letal responses to SARME 6,18,20 and TPD 28,32 , very limited information is available on the treatment-related long- term changes to the facial soft tissues. The only published studies have consid- ered SARME patients, and have used cephalometric soft-tissue profiles 11 or photographs 5 . Both methods provide very limited information and do not take into account the 3-D nature of facial soft-tissue changes. Morphological changes after orthodontics or facial surgery can be com- plex and involve a 3-D modification of shape and size. The major problem in analysing facial changes after treatment has been the inability to capture 3-D facial anatomical co-ordinates. Different Int. J. Oral Maxillofac. Surg. 2008; 37: 810–818 doi:10.1016/j.ijom.2008.05.006, available online at http://www.sciencedirect.com 0901-5027/090810 + 09 $30.00/0 # 2008 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.