Manual maximum closing torque in three implant abutment systems

Background and Aims: Diferences whithin shape and size of hand wrenches in diferent systems could affect the torque applied. Therefore, evaluation of wrenches has been emphasized. The aim of the present study was to compare the torque values of the long and short torque wrenches in different implant systems including ITI, Implantium and Nobel Biocare. Materials and Methods: In this experimental trial, 5 dentists with at least 5 years of professional experience closed the abutment screw in different implants systems using the long and short manual wrenches while the wrench-induced torque values were calculated by digital torque-meter. Torque application was done for 3 times with 10-minutes resting time between each wrench uses in the habitual closing torque manner. Data were analyzed using two-way analysis of variance test in different implant systems, while the paired comparisons were done using Tukey post hoc test. Results: The maximum torque values of the long manual wrenches were 27.73±4.57 Ncm, 34.6±8.09 Ncm and 30.6±6.94 Ncm for the ITI, Implantium, and Nobel Biocare systems, respectively. While the values were reported to be 26.4±5.3 Ncm, 35.27±7.94 Ncm and 30.13±5.26 Ncm in the short manual wrenches for the ITI, Implantium and Nobel Biocare systems, respectively. Significant differences were found between ITI and Implantium (P<0.0001), and between Implantium and Nobel Biocare systems (P<0.021). However, no significant differences were observed between ITI and Nobel Biocare systems regarding wrench-induced torque values (P>0.05). Conclusion: From the results, the torque values obtained by different long and short manual wrenches were specific to different implant systems. These values were less in ITI and Nobel Biocare systems and higher in implantun than those range provided for the implant systems by the companies.