Dataset for Assessment of the prosthetic retention of a frictional implant system with different mechanical testing methods
Different from screw implant systems, in which the fixation of the prosthetic abutment is verified during screwing using a torque ratchet, frictional implant systems do not present specific devices or methods to verify the fixation of the prosthetic component, which may cause component loosening when fixed incorrectly. This study aims to assess a new method to verify the stability of the prosthetic connection between frictional implants and abutments with a torsion test, directly comparing it with a tensile test. It also analyzes the influence on the mechanical response, for both tests, to the number of activations applied to the prosthetic components. An implant system with a frictional connection was selected for the study. The prosthetic abutments were attached to the implants and connected with an activation device of the system. The connection was performed at four different activation levels: 1, 3, 6, and 10 impacts caused by the device, forming four different assessment groups. For each group, half the samples were referred to tensile tests, and the other half was subjected to torsion assessments. The data obtained (avaliable on .xlsx and .bio files - BioEstat 5.3 software file) were subjected to one-way analysis of variance (one-way ANOVA), followed by Tukey's multiple comparison test (=0.05), to indicate which groups presented statistically significant differences. Lastly, Pearson's test was applied to assess whether there was a correlation between the values obtained in both mechanical tests. Both mechanical assessment methods showed that increasing the number of prosthetic activations increases the retention between implants and abutments. However, the difference of increased retention tends to decrease with the number of activations. The tensile test results show that the difference of maximum force values obtained is significantly different only when highly differing from the number of impacts. The torsion assessment presented statistically significant differences also for groups that highly differed from the number of impacts, and there was a difference between 1 and 3 activations. When correlated, the methods statistically present a moderate and positive relationship, meaning they show a growing tendency of torque and force values as the number of activations on the component increases. The study showed that the higher the number of activations performed on frictional abutments, the higher the retention of the implant connection. However, this retention tends to stabilize as the number of impacts increases. Both mechanical tests may assess the retention of frictional components, but the torsion test showed higher sensitivity. The torsion method is practical, simple, and closer to the dynamics of multidirectional movements of the forces applied to teeth.
Steps to reproduce
This study used 80 frictional Morse taper implants (Arcsys Dental Implant, FGM Dental Group, Joinville, Brazil) with 3.8 mm of diameter and 13 mm of length. Eighty prosthetic abutments of the same implant system were also used, in the Arcsys foldable abutment for the screw-retained restoration model, with 3.5 mm of transmucosal height. The implant-component set was connected with a device developed by the manufacturer of the implant system, called the Abutment Placement tool. Aiming to simulate a clinical condition closer to the impact produced by prosthetic activation, an apparatus was assembled consisting of two polymer plates for biomechanical tests (Polyurethane Sawbones™ solid foam, 40 PCF, USA), with dimensions of 40 mm x 80 mm x 20 mm and a bench lathe. Initially, the blocks were joined by the bench lathe, and 10 perforations were made with an Arcsys drill, with 3.4 mm of diameter and 13 mm of depth. The implants were placed in the cavities right after the perforations. The abutments were activated on the implants with the Abutment Placement tool. At this stage, each group of 20 samples received a defined number of activations (TAPS) with 1, 3, 6, and 10 impacts. After activation, the polyurethane plates were loosened from the bench lathe and separated, releasing the sets activated. Each group activated by the hammer with 1, 3, 6, and 10 TAPS were randomly divided into two groups for the tensile and torsion mechanical tests, resulting in 40 units for each test. For the tensile test, each implant-abutment (IA) set of subgroups 1TE, 3TE, 6TE, and 10TE was attached to an universal testing machine, model EMIC DL 3000, with a cell load of 50 kgf. The tensile test was performed at a speed of 1 mm/min, recording the maximum force value achieved, which was defined as the force required to cause this disconnection. The torsion test used a LUTRON digital torque meter, model TQ-8800, and a socket wrench for abutment extraction for screw-retained restorations, which is a device to remove intra-oral abutments. Each IA set of subgroups 1TO, 3TO, 6TO, and 10TO was first attached to the extraction wrench and then connected to the mandrel of the digital torque meter, in the implant region. A manual rotary movement was performed in the extraction wrench, in which the digital torque meter recorded the maximum torque value obtained to rupture the mechanical overlap between the surfaces of abutment and implant. The data obtained in the tensile and torsion mechanical tests were subjected to one-way analysis of variance (one-way ANOVA) to assess whether there were differences between the groups, followed by Tukey's multiple comparison post-hoc test to indicate which groups showed statistically significant differences. Lastly, Pearson's test was applied to assess whether there was a correlation between the values obtained in both mechanical tests. The BioEstat 5.3 software was used for the statistical analysis at a 5% significance level (=0.05).