Evaluation and comparison of mechanical properties between commercially available mini-implants: An in vitro study

Objective: The objective of this study is to evaluate the mechanical properties of different commercial brands of mini-implants by subjecting them to loads perpendicular to their long axis. Materials and Methods: A total of 120 mini-implants were divided into six groups (n = 20): Group 1A - 20 stainless steel (SS) mini-implants (SK Orthodontics, India), Group 1B - 20 SS mini-implants (BK Orthodontics, India), Group 1C - 20 SS mini-implants (JSV Surgicals, India), Group 2A - 20 titanium mini-implants (Koden surgical, India), Group 2B - 20 Titanium mini-implants (JSV Orthodontics, India), and Group 2C - 20 titanium mini-implants (Dentos, Korea) were used. The mini-implants were placed perpendicularly into 12 acrylic blocks and were submitted to mechanical tests using a standard universal testing machine (ACME, India. Model no. UNIT TEST-10). The different forces required to fracture mini-implants after undergoing 0.5, 1, 1.5, and 2 mm deformation was assessed. Results: Mini-implants in Group 2C (Titanium Dentos Korea) required the greatest force to deform and fracture, whereas Group 1C (JSV Surgicals, India) had the lowest fracture force. Statistically significant differences were seen when an intragroup comparison was done. Statistically significant differences were seen in the comparison between the SS and titanium groups (P < 0.05). The SS group required lower forces to deform and fracture as compared to the titanium group. Conclusions: SS mini-implants exhibited a high degree of resistance to deform and fracture, but they were inferior compared with titanium mini-implants. Titanium mini-implants required higher force values to deform and fracture.