EFFECT OF INCREASED CROWN-IMPLANT RATIO ON THE STRAIN DEVELOPED AROUND SHORT DENTAL IMPLANTS (IN VITRO STUDY)

Abstract

INTRODUCTION:Implants in atrophic posterior regions of the jaw often require short dental implants leading to increased crownimplant ratio and mechanical stress. Short and small diameter dental implants have been associated with higher risk of biomechanical complications and implant failure. However the use of short implants has become increasingly common due to anatomic limitations and need to avoid surgical rehabilitation of the reduced ridge. . OBJECTIVES: Evaluation of the effect of increased crown-implant ratio on the strain developed around short dental implants compared to conventional implants length. MATERIALS AND METHODS: A bounded saddle replica was simulated using polyurethane test blocks where fourteen dental implants have been placed. Specimens were divided into two parallel groups (n=7) according to implant length, Group (I) -implants of conventional length, Group (II) implants of short length. Strain gauges were connected to a strain meter to record the developed strain. A universal testing machine was used for load application up to 100 N. The data were statistically analyzed (p≤0.05). RESULTS: Group I exhibited the lower mean micro-strain values (512.26 ± 427.39µe) than Group II (804.05 ± 487.37µe). There was no statistically significant difference between both groups (p > 0.05). There was a statistical significance between oblique loads and vertical loads for each group. CONCLUSIONS: Increasing the crown implant ratio had no significant effect on the strains developed around dental implants.