Destruction of Osseointegration on Fitting Abutment by the Torque Wrench

-Part 1． The Special Quality of the Torque Wrench-

Abstract

Destruction in osseointegrated bone-implant interface occurred due to special torque wrench (STERI-OSS®) after five months reverse-torque failure.
The purpose of this study was to evaluate the wrench action with the torque measurement system. The results were as follows:
1. Measurement of torque wrench action revealed
1) to fast torque speed (0.7s/ratchet point) was 2.894 kgf・cm (28.38 Ncm).
2) to slow torque speed (2.3s/ratchet point) was 3.296 kgf・cm (32.30 Ncm)
2. Measurement of loading torque wrench revaled that slow torque speed was loading more powerful than fast.
The data of torque wrench in companies shows that power of torque wrench classified into three categories.
The most powerful group showed 3.059 kgf・cm (30Ncm) or more, second group showed 2.039～2.957kgf・cm(20～29 Ncm), and least powerful group showed 1.937 kgf・cm (19 Ncm)less.
In our experience, power of torque wrench indicated 3.568 kgf・cm (35 Ncm). The power corresponded to the most powerful group in the company data.
The user must be careful to use the torque wrench.