Work

Evaluation of Orthodontic Mini-Implants’ Stability Based on Insertion and Removal Torques: An Experimental Study

Year: 2025

Type: article

Abstract: Orthodontic mini-implants (MIs) are excellent alternative skeletal anchorage devices. Their stability is important for their survival, requiring appropriate torque application during insertion and removal. Objective: This study aimed to evaluate the influences of the diameter and brand of MIs on their stability by measuring the maximum insertion and removal torques after they had been aged in a pH 7 artificial saliva for 4 weeks at 37 °C. Methods: Forty Ti6Al4V alloy MIs of two different brands and diameters were divided into four groups. They were placed in artificial bone blocks using the NSK® Surgic Pro coupled with a digital torque gauge (Centor Touch Star TH®) to measure the maximum insertion and removal torques. Results: After ageing, the Fatscrew (Fts) MIs were more stable when removed than the white brand (WB) MIs. The WB MIs lost stability over time, while the Fts MIs—especially the 2.0 mm ones—maintained good stability. Conclusions: The significant differences between the tested groups, especially the stability observed in the 2.0 mm Fts MIs compared to the other groups, highlight the importance of brand and diameter size in the effectiveness of MIs.

Source: Bioengineering

DOI: 10.3390/bioengineering12050549