Evaluation of insertion torque of different orthodontic miniscrews: An in vitro study


  • Hussein Ahmed Al- Obaidi Department of P.O.P, college of dentistry, university of Mosul, Mosul, Iraq.
  • Mangur Maghdid Nadir Department of P.O.P, college of dentistry, university of Mosul, Mosul, Iraq.




Miniscerw, Dentos min screws, 3M miniscrews, Torque insertion


Background and objective: The purpose of this study was to evaluate the torque insertion for drill and non drill techniques of two commercially available miniscrews. Methods: Eighty mini screws (forty Dentos miniscrews/Korea and forty 3M miniscrews/USA), having the same length and diameter, were divided into two groups for each type. Two techniques, non-drill and drill, were used. In drill techniques, manufacturer recommended drill was used. Two bovine tibias were obtained. The first technique used pre drill hole, which was made in the bone using the recommended bur (1.0 diameter). The mini-screw was placed at 9 mm manually, then the remaining 1 mm was inserted through digital torque meter. The same procedure was repeated but without a pilot hole. Results: 3M miniscerws gave high torque insertion in two techniques. Conclusion: The shape, thread design and tip geometry of miniscerw play an important role in the torque insertion.


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How to Cite

Al- Obaidi, H. A., & Nadir, M. M. (2016). Evaluation of insertion torque of different orthodontic miniscrews: An in vitro study. Zanco Journal of Medical Sciences (Zanco J Med Sci), 20(1), 1153_1159. https://doi.org/10.15218/zjms.2016.0003



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