In this research, the effects of torque tightening on the stress distribution in double lap simple bolted and hybrid (bolted-bonded) joints have been investigated numerically. In order to determine the bolt clamping force value due to tightening torque in simple bolted and hybrid joints, which is necessary in numerical simulation, an experimental approach has been proposed. To do so, two kinds ...

STATEMENT OF PROBLEM The cone-screw abutment has been shown to diminish micromovement by reducing the burden of component loosening and fracture. However, anecdotal concern for cold welding of cone-screw joints in implant design has been identified as a potential source for lack of retrievability. PURPOSE This comparative study evaluated the loosening torque, as a percentage of tightening tor...

The paper a nonlinear model of bolt joints structure in vibration environment is built, including the friction, contact and so on complex nonlinear factors. Structure Intensity (SI) of it is calculated by Finite Element Method (FEM) as an approach for the state identification of bolts joints structure in vibration environment. The plots of the structure intensity vector under different tighteni...

The tapered implant-abutment interface is becoming more popular due to the mechanical reliability of retention it provides. Consequently, understanding the mechanical properties of the tapered interface with or without a screw at the bottom has been the subject of a considerable amount of studies involving experiments and finite element (FE) analysis. This paper focuses on the tapered implant-a...

The use of power screwdrivers and drills for tapping and screw insertion in surgery is becoming more common. It has been established from clinical observations that the use of a small air drill for inserting self-tapping screws provides improved coaxial alignment and precision, and that the drill should be stopped before the screw head is completely seated on the plate, presumably to reduce the...

PURPOSE The purpose of this study was to evaluate the influence of tightening technique and the screw coating on the loosening torque of screws used for Universal Abutment fixation after cyclic loading. MATERIALS AND METHODS Forty implants (Titamax Ti Cortical, HE, Neodent) (n=10) were submerged in acrylic resin and four tightening techniques for Universal Abutment fixation were evaluated: A ...

Aims Bone fracture fixation in orthopaedic surgery occurs with the use of implants, such as bone screws. Screws are tightened, typically manually, with the level of tightening depending on surgeons’ manual feel. However, this subjective insertion torque control can lead to overtighening and screw stripping 1 . Previously our group has shown that stripping torque can be predicted based on the to...

in this research, the influence of bolt preload on the fatigue strength of 2024-t3 aluminium alloy double lap bolted joints has been studied experimentally and numerically. to do so, three sets of the specimens were prepared and each of them subjected to tightening torque of 1,2.5 and 5 n-m and then fatigue tests were conducted under various cyclic axial load levels. in the numerical method, th...

Implant-abutment assemblies are usually subject to long-term cyclic loading. To evaluate the dynamic fatigue performance of implant-abutment assemblies with different tightening torque values, thirty implant-abutment assemblies (Zimmer Dental, Carlsbad, CA, USA) were randomly assigned to three tightening groups (24 Ncm; 30 Ncm; 36 Ncm), each consisted of 10 implants. Five specimens from each gr...