Assessment of Fracture Resistance and Marginal Adaptation between two different Implant Hybrid Abutment materials.

Abstract

This in-vitro study was designed to evaluate the fracture resistance and marginal adaptation of hybrid implant abutments and crowns using two different materials, lithium disilicate (E.max) and high performance polymer (BioHPP).

Twenty-eight implant dummies were embedded perpendicularly in an auto polymerizing resin (techno vit). Twenty-eight hybrid implant abutments and crowns crown simulating a maxillary first premolar were designed and milled using CAD/CAM system then pressed. These hybrid abutments and crowns were divided into four main groups according to type of material of abutments and crowns.

Titanium bases were cemented to their respective abutments using self-curing resin cement after surface treatment of the bonding surfaces then crowns were cemented to their respective abutments using self etch / self adhesive dual cure resin cements. Titanium bases were surface treated using 50 µm aluminum-oxide while lithium disilicate ceramic restorations bonding surfaces were treated using 9.5% hydrofluoric acid to roughen the surfaces and increase surface area for bonding. Universal primer was applied to all bonding surfaces before cementation and BioHPP restorations surfaces were blasted using 50 µm aluminum-oxide, 2bar. All restorations were cemented to their respective Titanium bases using self-adhesive resin cement then screwed to their respective implant models. Screw access channels were sealed with Teflon and composite resin. A stereomicroscope was used to measure the marginal adaptation before loading samples to fracture in a universal testing machine.