Comparison of skeletal anchorage distalizers effect in maxillary buccal segment: A systematic review

The aim of this systematic review was to evaluate and compare distalization effect in maxillary buccal segment between Palatal Skeletal Anchorage (PSA) and Zygoma Gear Appliance (ZGA) in evidence-based way.

Relevant studies published between January 2007 till December 2017 in PubMed, ScienceDirect, AJO-DO and Scopus electronic databases were identified. Inclusion criteria were: English language, study performed on humans, randomized or nonrandomized clinical trials, assessment of buccal segment distalization by Palatal or Zygomatic skeletal anchorage and patient's clinical preoperative and post-operative evaluation measured by cephalometric analysis. Quality assessment of included studies was performed.

A total of 357 scientific publications, articles, clinical trials related to the used keywords were identified during the search. Thirteen articles fulfilled our inclusion criteria. PSA system showed maxillary molar distalization distance range between 1.8 mm to 6 mm. ZGA presented molar distalization range from 4.37 mm to 5.31 mm. Results of maxillary buccal segment distal movement distance, treatment duration, adverse treatment effects or failure of mini-implants and the appliance were evaluated.

There was evidence that both of skeletal anchorage systems are effective nonextractive therapy for Angle Class II malocclusion and maxillary buccal segment distalization in greater than 3 mm space deficiency.