Influence of Methodological Variables on Fracture Strength Test Results of Intact Premolars: an ex-vivo study

The present ex vivo study evaluated the influence of periodontal ligament simulation, load inclination, and tip morphology on fracture strength test results on intact premolars. Forty maxillary premolars were divided into four groups, Group 1, with a 90° load inclination, spherical tip with a diameter of 3mm and periodontal ligament simulation (PDL+); Group 2, with a 90° load inclination, flat tip with a diameter of 2mm, PDL+; Group 3, with a 45° load inclination, flat tip with 2mm of diameter, PDL+; Group 4, 90° load inclination, spherical tip with 3mm diameter, without periodontal ligament reproduction. Interactions among variables and intergroup significance were tested with Wilcoxon rank-sum and Kruskal Wallis’s tests (p≤0.05). Statistically significant differences were found between groups B and C, but they were not found for the others. A 90° load inclination significantly increases fracture strength, while periodontal ligament simulation and tip morphology did not significantly influence the results.