Comparison of the effects of mini-implant and traditional anchorage on patients with maxillary dentoalveolar protrusion

Objective: To compare the treatment effects of mini-implants as anchor units with conventional methods of anchorage reinforcement in maxillary dentoalveolar protrusion patients in terms of skeletal, dental, and soft tissue changes. Materials and Methods: We searched the databases of the Cochrane Library, PubMed, OVIDSP, CBM, VIP, WanFang Data, and CNKI covering December 1966 to March 2016 for randomized controlled trials (RCTs) and clinical controlled trials that compared the treatment effects of mini implants with conventional anchorage reinforcement in maxillary dentoalveolar protrusion patients. Literature filtering, data extraction, and methodological quality evaluation were finished independently by two researchers and disagreements were solved by discussion. Meta-analysis was performed when possible; otherwise descriptive assessment was done. Results: Through a predefined search strategy, we finally included 14 eligible studies. Eight outcomes were evaluated in this study: maxillary incisor retraction, maxillary molar movement, U1-SN, SNA, SN-MP, UL-E Plane, NLA and G-Sn-Pg. Conclusions: Mini-implant anchorage was more effective in retracting the anterior teeth, produced less anchorage loss, and had a greater effect on SN-MP for the high-angle patients than did traditional anchorage. Both mini-implants and traditional anchorage underwent decreases in on U1-SN and SNA. More qualified RCTs are required to make reliable recommendations about the anchorage capacity of mini-implant and traditional anchorage in patients with maxillary dentoalveolar protrusion, especially on the UL-E plane, NLA, and G-Sn-Pg.