Korean J Orthod.  2009 Apr;39(2):95-104. 10.4041/kjod.2009.39.2.95.

Effect of cutting flute length and shape on insertion and removal torque of orthodontic mini-implants

  • 1Department of Orthodontics, School of Dentistry, Chosun University, Korea. shlim@chosun.ac.kr


The purpose of this study was to evaluate the effect of length and shape of cutting flute on mechanical properties of orthodontic mini-implants. METHODS: Three types of mini-implants with different flute patterns (Type A with 2.6 mm long flute, Type B with 3.9 mm long and straight flute, Type C with 3.9 mm long and helical flute) were inserted into the biomechanical test blocks (Sawbones Inc., USA) with 2 mm and 4 mm cortical bone thicknesses to test insertion and removal torque. RESULTS: In 4 mm cortical bone thickness, Type C mini-implants showed highest maximum insertion torque, then Type A and Type B in order. Type C also showed shortest total insertion time and highest maximum removal torque, but Type A and B didn't showed statistically significant difference in insertion time and removal torque. In 2 mm cortical bone thickness, there were no significant difference in total insertion time and maximum removal torque in three types of mini-implants, but maximum insertion torque of Type A was higher than two other Types of mini-implants. CONCLUSIONS: Consideration about length and shape of cutting flute of mini-implant is also required when the placement site has thick cortical bone.


Cutting flute; Total insertion time; Maximum insertion torque; Maximum removal torque
Full Text Links
  • KJOD
export Copy
  • Twitter
  • Facebook
Similar articles
Copyright © 2021 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr