Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study

Objectives: To determine the effects of different stainless steel miniscrew implant lengths on maximum insertion torque and pull-out strength in a location with relatively low bone density and cortical bone thickness.

Materials and Methods: Thirty-six stainless steel miniscrew implants were evenly assigned to three groups (n=12) according to size: 2 mm x 8 mm, 2 mm x 10 mm, and 2 mm x 12 mm. The implants were wrenched into artificial bone blocks. The artificial bone blocks were made of two different densities, 20 pounds per cubic foot (pcf) and 10 pcf, to replicate the cortical and cancellous bone on the modified infrazygomatic crest area, respectively. The maximum insertion torque and pull-out strength were measured using a digital torque gauge and universal testing machine, respectively. One-way analysis of variance (ANOVA) and Tukey's multiple comparison test were performed. The significance level was determined at 5%.

Results: The 2 mm x 12 mm miniscrew implants had significantly greater maximum insertion torque (6.03 + 0.21 Ncm) than the 2 mm x 8 mm (4.91 + 0.20 Ncm) and 2 mm x 10 mm (4.88 + 0.18 Ncm) implants, whereas there was no significant difference between the 2 mm x 8 mm and the 2 mm x 10 mm implants. The pull-out strength of the 2 mm x 8 mm, 2 mm x 10 mm and 2 mm x 12 mm miniscrew implants were 76.49 + 1.54 N, 86.22 + 2.16 N and 108.91 + 2.88 N, respectively. The pull-out strength significantly increased in a length-dependent manner.

Conclusions: All groups provide appropriate maximum insertion torque for miniscrew implant placement in a location with relatively low bone density and cortical bone thickness.

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Damang T, Tripuwabhrut K, Jotikasthira D. Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study: Original articles. CM Dent J [Internet]. 2020 Sep 01 [cited 2024 Jul 15];41(3):23-30. Available from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=65

Damang, T., Tripuwabhrut, K. & Jotikasthira, D. (2020). Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study. CM Dent J, 41(3), 23-30. Retrieved from: https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=65

Damang, T., Tripuwabhrut Kanich and Jotikasthira Dhirawat. 2020. "Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study." CM Dent J, 41(3), 23-30. https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=65

Damang, T. et al. 2020. 'Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study', CM Dent J, 41(3), 23-30. Retrieved from https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=65

Damang, T., Tripuwabhrut, K. and Jotikasthira, D. "Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study", CM Dent J, vol.41, no. 3, pp. 23-30, Sep. 2020.

Damang Tonfon, Tripuwabhrut Kanich, Jotikasthira Dhirawat "Effects of Stainless Steel Miniscrew Length on Primary Stability: An in vitro Study." CM Dent J, vol.41, no. 3, Sep. 2020, pp. 23-30, https://www.dent.cmu.ac.th/cmdj/frontend/web/?r=site/viewarticle&id=65