Comparative evaluation of skeletally anchored modified intermaxillary versus intramaxillary force systems for maxillary molar distalization: A randomized clinical trial

BACKGROUND: Distalization in orthodontics is one of the conservative modalities for gaining space in orthodontics. The skeletally anchored distalizers avoid the adverse effects of the dentally anchored ones. OBJECTIVE: The current study aimed to evaluate the effects of the skeletally anchored modified Leaf Expander, (Leaf Expander ® , Leone SpA, Sesto Fiorentino, Florence, Italy) (MLE) as a distalizer versus the skeletally anchored modified Carriere Motion Appliance (CMA) (Henry Schein Orthodontics (HSO), Australia). PATIENTS AND METHODS: Thirty orthodontic patients, aged 15 to 18, were involved in the present study. Group I comprised 15 patients who were treated with the skeletally anchored modified Leaf expander (MLE as a distalizer. Group ΙΙ involved 15 patients who were treated by the skeletally anchored modified Carriere Motion Appliance (CMA. Amount of molar distalization, molar tipping, Overjet, ANB (angle formed between A point, Nasion and B point), and vertical skeletal changes (FH–MP) (angle formed between the Frankfort plane and the mandibular plane), arch length, and transverse dimensions have been assessed by using digital models. All data were analyzed using SPSS version 20.0 (IBM Corp., USA). Normality was verified by the Shapiro–Wilk test. RESULTS: Upper first molar distalization (U6–VRL) (distance from mesiobuccal cusp of upper first molar to vertical reference line from S point; measures distal movement.) showed a highly significant difference ( P < 0.001, d = 5.96 – very large), with the MLE achieving almost double the distal movement of CMA (−7.65 ± 0.74 mm for MLE Group, −3.03 ± 1.84 for CMA). CONCLUSION: The skeletally anchored modified Leaf expander (MLE) as a distalizer produces a greater amount of maxillary molar distalization and less molar tipping than that produced by the skeletally anchored modified Carriere Motion Appliance (CMA).