Abstract
Mini-implant-assisted rapid palatal expansion (MARPE) offers a non-surgical alternative for expanding the basal bone, increasing skeletal effects while minimizing undesirable dental side effects. This systematic review and meta-analysis evaluate the effectiveness of MARPE in terms of transverse skeletal development, dentoalveolar changes, and periodontal effects, with consideration of appliance design. A review was conducted across multiple databases, including PubMed, MEDLINE, Embase, Scopus, and Springer, covering studies published between 2005 and 2024. Randomized controlled trials involving MARPE, with specific attention to design variations (e.g., miniscrew type, number, diameter, length, position, and activation protocol), were selected. Transverse skeletal expansion, assessed via changes in the nasal width, was reported in six of seven studies, with an average increase ranging from 0.31 mm to 2.90 mm for MARPE, compared to 0.11 mm to 2.46 mm for conventional Hyrax expanders. Maxillary width expansion ranged from 2.89 mm to 9.08 mm with MARPE and from 2.59 mm to 8.51 mm with Hyrax. Periodontal changes were reported in six studies, although details were generally unclear. The use of four self-drilling miniscrews with once-daily activation over an extended period produced greater nasal width expansion, greater average skeletal expansion of the maxilla, and less dental inclination and dentoalveolar expansion compared to Hyrax. No significant differences were observed between short and long miniscrews, although wider miniscrews resulted in improved outcomes. The MARPE technique, especially when using a design with four self-drilling miniscrews and daily activation until the targeted expansion is reached, offers notable benefits compared to the conventional Hyrax appliance. This method improves both nasal and maxillary skeletal expansion, lessens dental inclination, and reduces negative effects relative to traditional approaches.