Influence of orthodontic mini-implant penetration of the maxillary sinus in the infrazygomatic crest region

Am J Orthod Dentofacial Orthop. 2018 May;153(5):656-661. doi: 10.1016/j.ajodo.2017.08.021.


Introduction: Mini-implants are widely used for predictable tooth movements, but insertion is often restricted by anatomic structures. The aims of this study were to investigate the incidence of penetration of mini-implants into the sinus and the relationship between penetration depth and sinus tissue.

Methods: Data from 32 patients who received mini-implants in the infrazygomatic crest were collected from a data base. The success rate of mini-implants was determined by clinical retrospective analysis. The incidence of penetration, penetration depth, and sinus configuration were investigated and compared between cone-beam computed tomography scans obtained immediately after insertion and before mini-implant removal.

Results: The overall success rate of mini-implants in the infrazygomatic crest was 96.7%, and 78.3% penetrated into the sinus. In the group in which penetration exceeded 1 mm, the incidence of membrane thickening was 88.2%, and the mean value of thickening was 1.0 mm; however, the variable values of penetration in the 1-mm group were only 37.5% and 0.2 mm, respectively (P <0.05).

Conclusions: The incidence of penetration of infrazygomatic crest mini-implants into the sinus may be high. Penetration through double cortical bone plates with limitation of the penetration depth within 1 mm is recommended for infrazygomatic crest mini-implant anchorage.

MeSH terms

  • Adult
  • Female
  • Humans
  • Male
  • Maxillary Sinus* / injuries
  • Orthodontic Anchorage Procedures / adverse effects
  • Orthodontic Anchorage Procedures / methods*
  • Prosthesis Implantation / methods
  • Retrospective Studies
  • Zygoma