Younger Age Raised Complication Risk in 1,196-Miniplate BAMP Cohort

Edited by Orthotown staff

Younger patients faced higher odds of miniplate complications, removal, and replacement during bone-anchored maxillary protraction, according to a retrospective cohort study of 299 growing patients published Aug. 7 in the American Journal of Orthodontics and Dentofacial Orthopedics.

Younger age at surgery was independently associated with a higher likelihood of complications, at an odds ratio of 0.70 with a 95% confidence interval of 0.51 to 0.96, of miniplate removal, at 0.68, and of replacement, at 0.62. Patient sex showed no significant association with any outcome.

Placement site was the other significant factor. Complications occurred substantially more often in the maxilla than the mandible, at an odds ratio of 3.09 with a confidence interval of 1.70 to 5.61 and P less than .001.

Against those risk patterns, overall performance was strong. Bollard-modified miniplate anchorage achieved a 96.5% success rate across 1,196 miniplates placed in patients with maxillary hypoplasia and Class III malocclusion between January 2007 and December 2019. Mean follow-up ran 4.2 years.

Failures were uncommon and often recoverable. Fifty miniplates, or 4.2%, developed mobility or inflammation during orthodontic loading. After conservative management, 18 regained stability, 24 were removed and successfully replaced, and eight were removed and not replaced. The authors noted that treating mobility or inflammation early helped preserve stability.

They concluded that Bollard-modified miniplates are a reliable skeletal anchorage system for bone-anchored maxillary protraction in children and adolescents, with complications more frequent in the maxilla and in younger patients.

Lieselotte De Bruyn, Veronica Scocca, Araceli Diez-Fraile, and Gwen R.J. Swennen conducted the study, which was approved by the ethics committee at AZ Sint-Jan Brugge in Belgium and received no specific funding.

All 1,196 miniplates were placed by a single surgeon at one institution, and the design was retrospective. Outcomes tied closely to surgical technique and case selection may not transfer directly to other operators.

Sources:
American Journal of Orthodontics and Dentofacial Orthopedics, “Success rate and complications of Bollard-modified miniplates for bone-anchored maxillary protraction in growing patients: A single-surgeon retrospective cohort study,” published online Aug. 7, 2026: sciencedirect.com/science/article/pii/S0889540626003483
DOI: doi.org/10.1016/j.ajodo.2026.06.017