Early Class III Protraction Facemask Treatment Reduces the Need for Orthognathic Surgery: A Multi-centre, Two-arm Parallel Randomized, Controlled Trial. (September 2016)

• Record Type: Journal Article
• Authors: Mandall, Nicky; Cousley, Richard; DiBiase, Andrew; Dyer, Fiona; Littlewood, Simon; Mattick, Rye; Nute, Spencer J.; Doherty, Barbara; Stivaros, Nadia; McDowall, Ross; Shargill, Inderjit; Worthington, Helen V.
• Is Part Of: Journal of orthodontics. Volume 43:Number 3(2016:Sep.)
• Page Start: 164
• Page End: 175
• Publication Date: 2016-09
• Subjects: Class III -- interceptive treatment -- orthognathic surgery -- protraction facemask; Orthodontics -- Periodicals; 617.643005
• DOI: 10.1080/14653125.2016.1201302
• Languages: English
• ISSNs: 1465-3125

Abstract

Objective: To evaluate whether patients who had received early class III protraction facemask treatment were less likely to need orthognathic surgery compared with untreated controls. This paper is a 6-year follow-up of a previous clinical trial. Design: Multi-centre 2-arm parallel randomized controlled trial. Setting: Eight United Kingdom hospital orthodontic departments. Participants: Seventy three 7- to 9–year-old children. Method: Patients were randomly allocated, stratified for gender, into an early class III protraction facemask group (PFG) ( n = 35) and a control/no treatment group (CG) ( n = 38). The primary outcome, need for orthognathic surgery was assessed by panel consensus. Secondary outcomes were changed in skeletal pattern, overjet, Peer Assessment Rating (PAR), self-esteem and the oral aesthetic impact of malocclusion. The data were compared between baseline (DC1) and 6-year follow-up (DC4). A per-protocol analysis was carried out with n = 32 in the CG and n = 33 in the PFG. Result: Thirty six percent of the PFG needed orthognathic surgery, compared with 66% of the CG ( P = 0.027). The odds of needing surgery was 3.5 times more likely when protraction facemask treatment was not used (odds ratio = 3.34 95% CI 1.21–9.24). The PFG exhibited a clockwise rotation and the CG an anti-clockwise rotation in the maxilla (regression coefficient 8.24 (SE 0.75); 95% CI 6.73–9.75; P < 0.001) and the mandible (regression coefficient 6.72 (SE 0.73); 95% CI 5.27–8.18; P < 0.001). Sixty eight per cent of the PFG maintained a positive overjet at 6-year follow-up. There were no statistically significant differences between the PFG and CG for skeletal/occlusal improvement, self-esteem or oral aesthetic impact. Conclusions: Early class III protraction facemask treatment reduces the need for orthognathic surgery. However, this effect cannot be explained by the maintenance of skeletal cephalometric change.