Purpose: It is still unclear if modifications in prosthetic/implant interface and implant alloy could affect mechanical behavior of extra-narrow implants. The aim of this study was to evaluate the mechanical behavior of two types of 2.9mm in diameter dental implant, by using physical and virtual mechanical testing. Materials and methods: Two different Morse taper implant systems were evaluated in the current study: Facility implants (2.9mm diameter, 5° angulation of the internal conical portion) versus Narrow GM implants (2.9mm diameter, 16° angulation of the internal conical portion). Groups were evaluated, according to these methodologies: Strength to failure test, Fractographic analyses, Strain gauge test and Thermomechanical cycling test. Results: Statistical analysis revealed a significant distinction (p<0.001) between groups, the mechanical fracture efficiency of the Narrow group was 25% superior to Facility group. The examination using SEM revealed that all implants experienced fractures, with a tendency for these fractures to transpire in the area where there was a lack of continuity at the abutment/implant interface. There was no difference between groups considering the strain around the cervical region of the Morse taper implants tested (p=0.987). The survival rate of crowns and prosthetic connections was 100%. There was no crown loosening, prosthetic component detachment, or fracture of either. Conclusion: The proposed modifications for the new implant/abutment system had a positive impact on the mechanical behavior of the implant, with a 25% increased in fracture resistance and better stress distribution. Clinically, the GM Narrow system has become more resistant, but both systems can securely be used in restricted areas, with low masticatory effort, as upper lateral incisor and inferior incisors.
Keywords: biomechanics, FEA, single implant, extra narrow dental implant
