Abstract
The aim of this study was to evaluate by three-dimensional finite element analysis (3D-FEA) the biomechanics involved in bar-framework system for overdentures. The studied factors were latero-lateral angulation in the right implant (-10, -5, 0, 5 and 10 degrees), and different bar cross-sections (circular, Hader and oval) presenting horizontal misfits (50 or 150 µm) on the opposite implant. Positive angulation (5 and 10 degrees) for implant inclination to mesial position, negative angulation (-5 and -10 degrees) for distal position, and zero degree for parallel implants. The von Mises stresses evaluated the bar, screw and the implant; maximum principal, minimum principal and shear stress analyses evaluated the peri-implant bone tissue. Parallel implants provide lower stress in alveolar bone tissue; mesial inclined bars showed the most negative effect on prosthetic structures and implants. In conclusion, bar cross-section showed no influence on stress distribution for peri-implant bone tissue, and circular bar provided better behavior to the prosthetic system. Higher stress concentration is provided to all system as the misfit increases.
Highlights
Rehabilitations associated to osseointegrated dental implants have been pointed as the best treatment choice for edentulous patients
The current study has shown that the increase of the horizontal misfit is directly related to the stress increase generated across the entire system, which is in agreement with a previous study [21]
When compared to the vertical misfit, the findings suggest that horizontal misfits may be more prejudicial for splinted implants
Summary
Rehabilitations associated to osseointegrated dental implants have been pointed as the best treatment choice for edentulous patients. Overdentures retained by two implants have been indicated as the minimum treatment to offer to edentulous patients [1,2]. This procedure stands out for having relatively lower cost when compared to fixed dentures [3] and superior results to conventional denture in various aspects, such as patient satisfaction, comfort, chewing ability, social activities, and quality of life [4]. Some of the commercially available retaining systems for overdentures are: O’ring attachment, bar-clip system, locators and telescopic crowns [6,7,8]. Bar-clip system has some biomechanical advantages due to the splinting of the implants, allowing better force distribution to all retaining components [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
