247 453

Cited 2 times in

The comparison of torque values in two types of miniscrews placed in rabbits: tapered and cylindrical shapes: Preliminary study.

 Kyung-Ho Kim  ;  Chooryung Chung  ;  Hyun-Mi Yoo  ;  Dong-Sung Park  ;  In-Sung Jang  ;  Seung-Hyun Kyung 
 KOREAN JOURNAL OF ORTHODONTICS, Vol.41(4) : 280-287, 2011 
Journal Title
Issue Date
Tapered shape ; Torque ; Miniscrew ; Stability
OBJECTIVE: This study compared the stability of cylindrical miniscrews (Cy, 7 mm in length) with that of tapered miniscrews (Ta, 5 mm in length), using torque values to determine if the healing time before loading affects the stability of the miniscrew and if the insertion torque is associated with the removal torque measured after a few weeks of healing. METHODS: Ta and Cy with different thread lengths were placed in the tibias of 12 female New Zealand white rabbits (body weight: 3.0 - 3.5 kg), and the maximum insertion torque values (ITV) were measured. No orthodontic forces were applied so as to allow us to determine the pure effects of the different shapes. After 3 different healing periods (2, 4, and 6 weeks), maximum removal torque values (RTV) were measured immediately before the rabbits were sacrificed. RESULTS: No miniscrews were loosened. There were no significant differences in ITV or RTV between the Ta and Cy nor were there any significant differences in the ITV and RTV between the 3 groups, which had different healing periods. There was a correlation between the ITV and RTV. CONCLUSIONS: Shorter Ta showed similar stability as Cy, as determined by torque values. This result strongly suggests that the tapered shape is more advantageous than the cylindrical shape. The RTV did not increase significantly over time. It is recommended that a miniscrew be loaded immediately; waiting a few weeks before loading should be avoided. The correlation between the ITV and RTV suggests that the ITV can be used to estimate a screw's future stability.
Files in This Item:
T201103188.pdf Download
Appears in Collections:
2. College of Dentistry (치과대학) > Dept. of Orthodontics (교정과학교실) > 1. Journal Papers
Yonsei Authors
Kim, Kyung Ho(김경호) ORCID logo https://orcid.org/0000-0002-8154-2041
Chung, Chooryung J.(정주령) ORCID logo https://orcid.org/0000-0001-9399-7193
사서에게 알리기


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.