Resistência a fratura de implantes de diâmetro extra-estreito

Abstract

The necessity to rehabilitate narrow mesio-distal spaces where surgeries for bone gain are not possible to be done, the company Neodent developed, in 2013, the extra-narrow implant called Facility with 2.9mm diameter, in grade 5 titanium and 5º prosthetic interface inclination, without internal screw; however, recurring prosthetic complications led the company to later develop the extra-narrow implant Narrow GM, with 2.9mm diameter, in grade 4 titanium and 16º prosthetic interface inclination, with internal screw. This study aimed to evaluate the biomechanical behavior of extra-narrow implants using a destructive method, analyzing the maximum yield strength of extra-narrow implants through a fracture resistance test. The tests were carried out using 10 implants from each group; the abutments were installed as recommended by the manufacturer and each abutment/implant assembly was positioned, 1 to 1, 4mm outside a metal stand, subjected to a 500kN load cell, with a speed of 0.5mm/min. A computer attached to the cell recorded the force exerted through force (N) x displacement (mm) curves. The results obtained were analyzed using the student t test, with a significance level of α=0.05, where was able to observe a mean force value until fracture for the Facility group of 225N, and for the Narrow group this value was 282N. Therefore, the Narrow GM implant was more resistant to fracture, due to the type of alloy in which it was manufactured, its prosthetic interface and macrogeometry, characterizing good mechanical behavior in terms of fracture resistance.