Miniplate-anchored maxillary protraction in adolescent patients with cleft lip and palate: A literature review of study design, type and protocol, and treatment outcomes

Objective: To review the study design, type, protocol, and treatment outcomes of miniplate-anchored maxillary protraction (MAMP) in adolescent patients with unilateral or bilateral cleft lip and palate. Setting/Sample population: Five retrospective and two prospective studies (n = 138 patients) were selected as per the inclusion criteria. Materials and Methods: The study design, type, protocol of MAMP and the amount of skeletodental change were investigated. Results: Two studies adopted type 1 (two miniplates at the infrazygomatic crest with a facemask), four studies adopted type 2 (four miniplates at the infrazygomatic crest and mandibular symphysis and use of intermaxillary elastics), and one study compared the two types. The mean start age was older than 10 years except one study. The mean duration was less than 1 year in two studies, between 1 and 2 years in three studies, and more than 2 years in two studies. The type 1 used 500 g/side for 12-14 h/d, and the type 2 used three increase methods (100, 200, 250 g/side; 75, 150, 250 g/side; 150, 200, and 250 g/side) for 24 h/d. The ranges of A point advancement were 0.5°-4.2° in ΔSNA and 1.7-5.6 mm in ΔA-vertical reference plane, respectively. The ranges of rotation of the palatal plane, occlusal plane, and mandibular plane were −1.5° to 2.0°, −2.0° to 2.0°, −1.5° to 3.2°, respectively. The increase of overjet was ranged from 2.3 to 5.8 mm. Conclusion: The MAMP therapy is effective for the correction of maxillary hypoplasia in adolescent cleft patients despite different types and protocols.