Evaluation of Biomechanical and Stress Distribution of Different Dental Implant Designs: Primary Stability and Photoelastic Analysis

Objectives: This study aimed to evaluate and compare the stress distribution and primary stability of three different designs of dental implants. Material and Methods: 24 implants Neodent (R) were used (n = 8): G1 - Alvim CM; G2 - Drive CM; G3 - Facility, submitted to insertion torque (IT) and pullout test, on 20 PCF (0.24 g/cm(3)) and 40 PCF (0.64 g/cm(3)) polyurethane blocks. For the stress distribution, by means of photoelasticity, axial and oblique loads (model at 30 inclination) of 100 N were performed, for reading and quantifying the fringe orders. According to the distribution data, a parametric or non-parametric analysis was performed (alpha = 0.05). Results: The IT was lower in G3 (p < 0.05) compared to G1 and G2, in 20 and 40 PCF polyurethanes. In the pullout, no difference (p > 0.05) was observed between G1 and G2, in both 20 and 40 PCF polyurethanes. In the comparisons between polyurethanes, higher values (p < 0.05) were obtained in the 40 PCF for IT and pullout. In the axial loading, lower stresses were observed in the cervical third and higher stresses in the middle and apical third of the implants. With the oblique inclination of the models, higher stresses were generated in the opposite side of the load, in the cervical third of G1, followed by G3 and G2. Conclusion: The results allow to affirm that G1 and G2 exhibit high primary stability and satisfactory stress distribution. Although G3 generates stresses comparable to other implants, its indication is limited in low density bones. (c) 2021 AGBM. Published by Elsevier Masson SAS. All rights reserved.