Title of article :
The effect of sterilization and number of use on the accuracy of friction-style mechanical torque limiting devices for dental implants
Author/Authors :
Fayaz, Ali Departments of Prosthodontics - Dental School - Shahid Beheshti University of Medical Sciences, Tehran , Mahshid, Minoo Departments of Prosthodontics - Dental School - Shahid Beheshti University of Medical Sciences, Tehran , Saboury, Aboulfazl Departments of Prosthodontics - Dental School - Shahid Beheshti University of Medical Sciences, Tehran , Sadr, Jalil Departments of Prosthodontics - Dental School - Shahid Beheshti University of Medical Sciences, Tehran , Ansari, Ghassem Shahid Beheshti University of Medical Sciences, Tehran
Abstract :
Background: Mechanical torque limiting devices (MTLDs) are necessary tools to control a peak
torque and achieving target values of screw component of dental implants. Due to probable effect
of autoclaving and number of use on the accuracy of these devices, this study aimed to evaluate
the effect of sterilization and number of use on the accuracy of friction-style mechanical torque
limiting devices (F-S MTLDs) in achieving their target torque values.
Materials and Methods: Peak torque measurements of 15 new F-S MTLDs from three different
manufacturers (Astra Tech, BioHorizons, Dr. Idhe) were measured ten times before and after 100
steam sterilization using a digital torque gauge. To simulate the clinical situation of aging (number
of use) target torque application process was repeated 10 times after each sterilization cycle and
the peak torque values were registered. Comparison of the mean differences with target torque
in each cycle was performed using one sample t test. Considering the type of MTLDs as inter
subject comparison, One-way repeated measure ANOVA was used to evaluate the absolute values
of differences between devices of each manufacturer in each group (α = 0.05).
Results: The results of this study in Dr. Idhe group showed that, mean of difference values
signifi cantly differed from the target torque (P = 0.002) until 75 cycles. In Astra Tech group, also
mean of difference values with under estimation trend, showed a signifi cant difference with the
target torque (P < 0.001). Mean of difference values signifi cantly differed from the target torque
with under estimation trend during all the 100 cycles in BioHorizons group (P < 0.05).
Conclusion: The torque output of each individual device stayed in 10% difference from target
torque values before 100 sterilization cycles, but more than 10% difference from the target torque
was seen in varying degrees during these consequent cycles.
Keywords :
Calibration , dental implants , equipment failure , torque
Journal title :
Astroparticle Physics
