Fixed Functional Appliance Therapy With and Without Skeletal Anchorage in Class II Malocclusion: A Systematic Review of Randomized Controlled Trials

Abstract

For its synergistic effects in producing skeletal changes as well as to lessen the proclination of the lower incisors, which is a common negative result of mandibular advancement, fixed functional appliances with skeletal anchorage have recently been used. Objective was to evaluate the skeletal and dentoalveolar effects with fixed functional appliances with and without skeletal anchorage. Electronic database search and manual search were performed up to 2021, April in four databases namely The Cochrane Library, PubMed, Lilac, and Google Scholar. RCTs that employed the use of fixed functional appliances in Class II malocclusion with and without skeletal anchoring were collected. Two co-authors independently extracted the data, and a pre-designed template was followed during the data extraction process. Data including inclusion and exclusion criteria; study design, the year of publication; age and gender of the patients; type of fixed functional device; stage of skeletal maturation; size and site of mini-implant or miniplate placement, amount of force applied in grams or Newtons; method of study outcome assessment (2D or 3D); and follow up were collected. The skeletal and dentoalveolar parameters were extracted. The risk of bias was evaluated, and the SMD and 95% confidence intervals (CIs) were also calculated. Four RCTs were evaluated for qualitative and quantitative analysis. The review involved data of 179 Class II individuals. The results of a random-effects meta-analysis showed that the SNB differed significantly from the control group (SMD = 0.50 (95% CI –1.55 to –0.10)). No significant differences noted between the two groups in terms of lower incisor inclination and mandibular length changes [SMD = –0.04 (95% CI −2.06 to 1.98) and –1.33 (95% CI −3.28 to 0.62), respectively]. The studies under this were not able to provide enough data to draw any conclusions about the effects of using skeletal anchorage with FFA. According to the evidence that is currently available, using FFA coupled with skeletal anchorage does not appear to have any superior skeletal effects than those without skeletal anchorage.