J Korean Acad Prosthodont.  2011 Jul;49(3):197-205.

A study on accuracy and application of the implant torque controller used in dental clinic

• Joo YH
• Lee JH

Abstract

PURPOSE
This study was to evaluate the accuracy of the implant torque controller used in dental clinics and to investigate whether it was applied appropriately.
MATERIALS AND METHODS
Fifty dentists who work in dental clinics were enrolled in this study. Dental (implant) practice career, experience frequency of implant screw loosening and fracture, education of implant torque controller application and infection control methods were included in the survey. 25 Ncm and 30 Ncm of the tightening torque applied to the implant screw were measured by 50 clinicians. After measuring the torque value by using the torque controller, the torque mean according to where education about the implant torque controller was received was analyzed with independent t-test at the significance level of 0.05.
RESULTS
The torque controller used in private dental clinics showed 4.78% error ratio. When 50 dentists applied 25 Ncm to the implant screw was 29.0 +/- 8.4 Ncm, and that in 30 Ncm was 34.3 +/- 9.1 Ncm. Statistical significance was found between the group that was educated about implant torque application and the group that was not educated.
CONCLUSION
During the prosthodontic treatment with implant, there was difference between actual applied torsion force and the amount torque controller indicated. Clinicians have to not only be well-informed about the accurate usage method of the torque controller, but also keep and manage the torque controller so as to maintain continuous and accurate torque values. Through this, it is considered to achieve clinical results to minimize problems of screw loosening or fracture.

Keyword

Implant torque controller; Screw loosening; Abutment screw

MeSH Terms

Dental Clinics
Dentists
Humans
Infection Control
Prosthodontics
Torque

Figure

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  Fig. 1. Torque controller (Torque Ratch Wrench, Hader SA, Switzerland).

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  Fig. 2. Tonichi Torque Gauge (Model 9BTG-N, Tonichi America, USA).

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  Fig. 3. Torque controller accuracy test (A: square insert in the jaws of the Tonichi Torque Gauge, B: torque controller under test condition, C: torque controller is rotated until the detent releases).

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  Fig. 4. Implant fixture, abutment, abutment screws used for this study.

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  Fig. 5. A: digital torque gauge (MGT-12, Mark-10 Corp., NY, USA), B: custom made torque gauge holding apparatus.

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  Fig. 6. Torque controller application test.

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  Fig. 7. Dental practice, implant practice career of experimental trier.

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  Fig. 8. Implant screw loosening frequency on clinical practice.

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  Fig. 9. Implant screw fracture frequency on clinical practice.

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  Fig. 10. Mean error ratio on torque controller (25 Ncm).

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  Fig. 11. Mean torque value of individual trier on 25 Ncm test.

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  Fig. 12. Mean torque value of individual trier on 30 Ncm test.

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  Fig. 13. Mean torque values and standard deviation on 25 Ncm, 30 Ncm test (A: education group, B: non education group).

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