Clinical outcomes of skeletal anchorage versus conventional anchorage in the class III orthopaedic treatment in growing patients: a systematic review and meta-analysis

The aim of this systematic review was to evaluate the clinical outcomes of skeletal anchorage, compared to conventional anchorage, in the treatment of skeletal Class III malocclusion in growing patients. A systematic review was conducted following PRISMA guidelines. A specific search strategy was developed for PubMed, Web of Science, Embase, and Cochrane searching for randomized controlled trials and non-randomized clinical trials. Eleven interventions were assessed, three employing conventional anchorage (group A) and eight skeletal anchorage (group B). Nine pre-treatment (T0) and post-treatment (T1) mean cephalometric outcomes were statistically polled (SNA, SNB, ANB, Wits, Overjet, Overbite, SNMP, IMPA, U1PP). In total, 196 studies were identified, 17 studies were included in the qualitative and quantitative analysis. In the skeletal anchorage group, a greater increase in both ANB (+2.511°) and Wits (+4.691 mm) were observed and the increase in SNMP resulted well-controlled (+0.758°). The conventional anchorage group showed higher dentoalveolar side effects: increase in U1PP (+5.624°), decrease in IMPA (-0.866°) and increase in overjet (+5.255 mm). Treatments exploiting skeletal anchorage determined a better correction of skeletal Class III, thanks to a combination of greater advancement of the maxilla and more enhanced retrusion of the mandible. In all treatment protocols exploiting dental anchorage, the increase in the inclination of the central incisor resulted significantly greater. Further longitudinal studies are required to evaluate the long-term effects of skeletal anchorage in growing patients.