THE SAGITTAL ARCH DEVELOPER APPLIANCE: A Clinical and Radiographic Evaluation By El Hendawy F*, Khatab A .M., Abdelwareth A., Tanta University, College of Dentistry,Pediatric Dentistry; Orthodontic Department, Tanta ,Egypt S keletal class III malocclusion is a growth related facial deformity which increases if left untreated. 1 In many cases a developing class III is due to an anterior maxillary deficiency that needs orthope-dic management very early. For many practitioners child cooperation is a problem that postpones the use of a face mask so upper sagittal arch developer can be used easily as it doesn’t depend on patient cooperation. 2 The effectiveness of maxillary expansion and face –mask therapy in children with class III malocclusion was studied in a sample of 46 subjects in mixed denti-tion and compared with a control sample of 32 subjects with untreated class III malocclusion. The results indi-cated that the combination of a bonded maxillary expander and face-mask therapy is more effective in early mixed dentition than in late mixed dentition, specially with regard to the magnitude of the protusion effects on the maxillary structures. 3 A study was done by Kim et al (1999) to examine the effectiveness of maxillary protraction with orthopedic appliances in class III patients. A meta-analysis of relevant literature was performed to determine whether a consensus exists regarding controversial issues such as the timing of treatment and the use of adjunctive intraoral devices. The results indicated that protractive face-mask therapy is effec-tive in patients who are growing, but to a lesser degree in patients who are older than 10 years. 4 The skeletal, dental and soft tissue effects of face –mask /expansion therapy was determined by Kapust el al (1998 ) 5 and the effect of age on the treatment was also examinated. The results demonstrated that face mask /expansion therapy produces dentofacial changes that combine to improve the class III maloc-clusion, they also noted that face –mask therapy can provide a viable option for older children as well. Kama et al (2006) 6 examined the cephalometric changes in subjects with class III malocclusion after rapid palatal expansion (RPE) and facemask treat-ment. A Wilcoxon test was used to determine significant differences before and after treatment and a Mann-Whitney U-test was used to analyze differences between the treatment and control groups. Managing developing class III malocclu-sions with (RPE) and maxillary protraction presents favorable results, such as vertical and sagittal displacement of point A. Rapid maxillary expansion was performed by DeFigueiredo el al(2007)(7 ) by using Hyrax appli-ance, petit orthopedic face mask, high-pull chin cap an bioprogressive fixed mechanics. The results were satisfactory from both esthetic and functional stand-points, providing adequate overjet and overbite, and with stability at 5 years post treatment. 16 November/December 2011 JAOS
Journal of the American Orthodontic Society November-December 2011: Page 16
