Evaluation of the Dento-skeletal effects of Mini-implant Assisted Rapid Palatal Expansion in a sample of Adult Orthodontic Patients: A prospective clinical study

Abstract

Objective: to evaluate the dentoskeletal effects of maxillary skeletal expander (MSE) in adult orthodontic patients, using Cone Beam Computed Tomography (CBCT). Patients and Methods: The current study was conducted on 14 adult orthodontic patients (4 males and 10 females), with their age ranged from 18 to 21 years, treated with a special type mini-implant assisted rapid palatal expander called, MSE (Maxillary Skeletal Expander) to correct transverse maxillary deficiency. The CBCT images were performed before the start of the orthodontic expansion (T1) and 3 months after the last activation (T2). Paired t-test, and descriptive statistics were used to evaluate the amount and the pattern of the mid-palatal suture opening, the total amount of maxillary expansion and the change in the inter-molar distance and molar inclination. Results: Four patients were dropped-out for different reasons, so, the statistical analysis was performed only on 10 patients (3 males, 7 females). The midpalatal suture split by 2.96mm and 2.64mm at the anterior nasal spine (ANS) and the posterior nasal spine (PNS) respectively, with a ratio of 89% between the PNS and the ANS. The maxillary width showed increase by 2.99 mm between the right and left zygomaticomaxillary sutures. The inter-molar distance and the molar inclination showed increase by 5.3 mm and 5.4 o respectively. Conclusions: MSE is an efficient appliance for producing rapid palatal expansion and mid-palatal suture opening in adult orthodontic patients and can be used as an alternative to the surgically assisted rapid palatal expansion. MSE expansion affects the involved molars, causing increased inter-molar distance with limited buccal tipping.