The effects of combined skeletal anchor plates and removable TMA traction springs in growing patients with maxillary deficiency

Document Type : Original Article

Authors

1 Department of Orthodontics,Faculty of Dentistry, Misr University for Science and Technology.

2 Department of Orthodontics, Faculty of Dentistry, Suez Canal University.

Abstract

The purpose of this study was to evaluate the efficiency of bone anchored maxillary protraction (BAMP), using combined skeletal maxillary mini plates and a removable TMA traction spring appliance (TTSA), in patients with Class III malocclusion. Twenty cases (n=20) who were in prepubertal skeletal growth periods were used in the study. All subjects had skeletal and dental Class III malocclusions with maxillary deficiency, and anterior crossbite. The samples were categorized into two groups: Group A comprised 6 girls and 4 boys (n=10) (mean age, 11.91 years) received treatment using (BAMP). Three hundred fifty to 400 g of force per side was applied to the (TTSA) from the titanium miniplates (HUBIT, Korea) inserted in each infrazygomatic buttress of the maxilla. Total treatment time was 6.9±2.63 months. Group B comprised 7 girls and 3 boys (n=10) (mean age, 11.05 years) was the untreated control group. Lateral cephalometric films were obtained at the beginning (T1), at the end of treatment (T2) and at follow up 6 months later in both groups and analyzed with independent-sample t tests (P <0.05).The miniplates were able to withstand the orthopedic forces exerted during active treatment. Cephalometric findings showed significant sagittal measurements of the maxilla, as well as significant improvements in the mandibular skeletal measures at Point B, where SNA and SNB angles have improved significantly between T1 and T2 (p <0.001) without significant maxillary incisor movement. Statistically significant increases were observed in the vertical dimension, where rotation of the mandible and increased facial height were evident.Compared with growth of the untreated Class III subjects, it is suggested that this treatment approach can offer an advantage for correcting Class III patients with mild/moderate maxillary deficiency.