Factors affecting success and failure of orthodontic mini-implants: A retrospective review.

Objective: To determine the factors associated with success and failure of orthodontic mini-implant (MI) in orthodontic patients. Study Design: Retrospective Review. Setting: Department of Orthodontic, Sharif Medical and Dental College. Period: September-November 2021. Material & Methods: The files and records of all patients from last 3 years fulfilling the selection criteria were reviewed by an orthodontic consultant and two post-graduate residents and data was recorded in a predesigned proforma. All mini-implants were inserted by a single operator (orthodontic consultant) with a hand driven autoclaved screwdriver compatible with Dentaurum Mini-Implant (Tomas Pin©). Length and Diameter of all mini-implants were chosen to be constant with 8mm length and 1.5mm diameter. All patient-related and location-related factors related to success of mini-implant were assessed. Results: The success rate in females (85.9%) was higher than in males (69.5%) and there was significant difference between male and females (p=0.023). The TADS inserted in higher bone quality (Q1=95.8%, Q2=94.4%) showed a significant difference (p=0.001) in success rate than those inserted in lower bone quality (Q3=38.1%, Q4=23.1%). Conclusion: Bone quality and gender were significant factors, which impact the clinical performance of orthodontic mini-implants. Other patient-related and location-related factors did not significantly impact the success rate of orthodontic mini-implants.