Maxillary dento-skeletal outcomes after orthopedic forward (class III) and backward (class II) traction in growing subjects

BACKGROUND: This retrospective study investigated the treatment effects produced by two orthopedic appliances, an extraoral orthopedic traction on Stephenson plate (SP) in skeletal Class II malocclusion and Delaire Facial Mask (FM) in skeletal Class III malocclusion. METHODS: FM Group comprised 25 patients (13 males; 12 females, mean age 9.3 years, CS 1-2) undergoing Delaire Facial Mask therapy (mean treatment duration 1.5 years +/- 1.2, 700-800 gr per side). SP Group comprised 24 patients (9 males; 15 females, mean age 10.5 years +/- 1.9, CS 1-3) treated with extraoral orthopedic traction on Stephenson plate (mean treatment duration 1.6 years +/- 0.8, 700-900 gr per side). For all subjects lateral cephalograms before (T0) and after (T1) therapy were obtained and traced. Descriptive statistics, t-test and Shapiro-Wilks test were calculated for each variable. RESULTS: A mesial movement of the maxillary bone of 2.4 mm in the FM group and a distal movement in the PS group (0.4 mm) was found. SNA degrees was reduced 1.4 degrees after SP and increased 0.7 degrees after FM. The overjet decreased by 4 mm after SP, while it grew after FM by 2.4 mm, as well as molars relationships (4.5 vs. 0.8 mm). CONCLUSIONS: Facemask induced greater skeletal movements than extraoral traction on Stephenson plate. PS produced a limited downward movement of the whole maxilla together with notable incisors and molars back corrections. Based on our results, it could be speculated that orthopedic mesial traction of maxillary bone may result easier than the distal movement.