Effect of cutting flute length and shape on insertion and removal torque of orthodontic mini-implants.
10.4041/kjod.2009.39.2.95
- Author:
Soon Dong YUN
1
;
Sung Hoon LIM
Author Information
1. Department of Orthodontics, School of Dentistry, Chosun University, Korea. shlim@chosun.ac.kr
- Publication Type:Original Article
- Keywords:
Cutting flute;
Total insertion time;
Maximum insertion torque;
Maximum removal torque
- MeSH:
Torque
- From:Korean Journal of Orthodontics
2009;39(2):95-104
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVE: 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.
