Abutment screw loosening of dental implant is a major problem in the treatment of
dental implant.
The purpose of this study was to examine the effect on the prevention of screw loosening
according to tightening method and using of washer.
In the f...
Abutment screw loosening of dental implant is a major problem in the treatment of
dental implant.
The purpose of this study was to examine the effect on the prevention of screw loosening
according to tightening method and using of washer.
In the first experiment, using a implant fixture and precisely fabricated temporary cylinder,
the loosening torque was measured by tightening the screw 5 times repeatedly.
In the second experiment, the fabricated crown and implant fixture was tightened by
the screw that is attatched washer and then the loosening torque was measured after
loading it 1800’ 12600 times under the force of 150N.
The results were as follows.
1. The highest loosening torque appeared after tightening 3 times repeatedly(p<0.01).
2. When the washer was used, the loosening torque was increased significantly under the
loading 1800 tim es(p<0.0l),
3. When the washer was used, the loosening torque was increaed under the loading 12600
times, but it is statistically not significant(p〈0.01).
The first experiment results mean that 3 times repeated tightening screw is most effective
clinically. The second results mean that washer is effective in prevention screw loosening,
but the effect is decreased with increasing load.