This study aimed to assess the combined effect of dismantling before sterilization and aging on the accuracy (±10% of the target torque) of spring-style mechanical torque devices (S-S MTDs).

Twenty new S-SMTDs from two different manufacturers (Nobel Biocare and Straumann: 10 of each type) were selected and divided into two groups, namely, case (group A) and control (group B). For sterilization, 100 cycles of autoclaving were performed in 100 sequences. In each sequence, 10 repetitions of peak torque values were registered for aging. To measure and assess the output of each device, a Tohnichi torque gauge was used ( P <0.05).

Before steam sterilization, all of the tested devices stayed within 10% of their target values. After 100 cycles of steam sterilization and aging with or without dismantling of the devices, the Nobel Biocare devices stayed within 10% of their target torque. In the Straumann devices, despite the significant difference between the peak torque and target torque values, the absolute error values stayed within 10% of their target torque.

Within the limitations of this study, there was no significant difference between the mean and absolute value of error between Nobel Biocare and Straumann S-S MTDs.