The study on the removal torque of the diamond like carbon coated titanium abutment screws.
- Author:
Jai young KOAK
1
;
Seong Joo HEO
;
Ik Tae CHANG
;
Soon Ho YIM
;
Jong Yeop LEE
;
Kwang Ryeol LEE
Author Information
1. Department of Prosthodontics, Collage of dentistry, Seoul National University, Korea. heosj@plaza.snu.ac.kr
- Publication Type:Original Article
- Keywords:
Removal torque;
Abutment screw;
Diamond Like Carbon;
Friction coefficient
- MeSH:
Carbon*;
Diamond*;
Friction;
Hardness;
Prosthodontics;
Titanium*;
Torque*
- From:The Journal of Korean Academy of Prosthodontics
2003;41(2):128-135
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
STATEMENT OF PROBLEM: Implant screw loosening remains a problem in implant prosthodontics. Some abutment screws with treated surfaces were introduced to prevent screw loosening and to increase preload. DLC(Diamond Like Carbon) film has similar properties on hardness, wear resistance, chemical stability, biocompatibility as real diamond materials. PURPOSE: The purpose of this study was to investigate the effect of lubricant layer on abutment screw and to discriminate more effective method between soft lubricant and hard lubricant to prevent screw loosening. MATERIAL AND METHOD: In this study, 1mum thickness DLC was used as protective, lubricating layer of titanium screws and 3 times removal torque was measured on the abutment screws to investigate the difference in 10 coated and 10 non-coated abutment screws. RESULTS: The results indicated that the implants with DLC coating group were not more resistant to the applied force in screw loosening. At 32Ncm, the 3 times removal torque in DLC group were 27.7+/-2.89, 25.85+/-2.35 and 26.2+/-2.57. The removal torque in no-coated abutment screws were 27.85+/-4.23, 27.35+/-2.81 and 27.9+/-2.31, respectively. CONCLUSION: The lubricant layer used in this study was Diamond Like Carbon(DLC) and it have a properties of hard and stable layer. The DLC coating layer was hard enough to prevent distortion of screws in the repeated unscrewing procedure in clinical situation. The reduced friction coefficient in hard DLC layer was not effective to prevent screw loosening.
