The Precision of Mechanical Torque Wrenches Used for Implants in Dental Offices.
OBJECTIVE
This study aimed to investigate the precision of mechanical torque wrenches used for implants in dental offices.


METHODS
Mechanical torque wrenches (n = 138) with two functional designs and made by three manufacturers were tested by three groups of investigators. Potential influences on accuracy were tested. Relative deviations from targeted torque values and the precision of recorded torque values were analyzed.


RESULTS
Most abutment screws were tightened too tightly rather than too weakly. Differences were apparent in the influence of the functional design of torque wrenches on their precision. No significant correlation between absolute frequency of use and relative deviation or precision was detected. Investigators with different levels of experience exhibited significantly different deviations from targeted torque values.


CONCLUSIONS
Average deviation from intended torque values, and levels of imprecision, are evidently not major problems in implant prosthetics; however, high torque values are a cause for concern.
Lars
L
Steinebrunner
Sönke
S
Harder
Stefan
S
Wolfart
Sandra
S
Freitag-Wolf
Matthias
M
Kern
D002983:Clinical Competence; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000295:instrumentation* / Q000592:standards; D004867:Equipment Design; D006801:Humans; D008422:Materials Testing; D012016:Reference Values; D015203:Reproducibility of Results; D019415:Torque