Investigastion of the bonding mechanisms between veneering and framework material of all-ceramic dental restorations

• Applicants: Professor Dr. Bernd Breidenstein; Professorin Dr. Meike Stiesch
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering ; Dentistry, Oral Surgery
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 272425256

All-ceramic dental prosthesis offers outstanding biocompatibility, excellent mechanical properties and aesthetic appearance. Regarding the mechanical and optical properties, a restoration made of yttria stabilized tetragonal zirconia (framework material) and porcelain (veneering material) matches the natural tooth closer than any available alternative. Due to the wide range of indications, all-ceramic restorations have the potential to replace metal-ceramic prosthesis as the standard therapy. So far, the failure rate of ceramic frameworks is higher compared to conventionell restorations with a metal framework, due to a lower bond strength between the components. Understanding the bonding mechanisms between yttria stabilized tetragonal zirconia and porcelain bears the potential for targeted improvement regarding tooth fracture by generating matched subsurface properties of both ceramics. The research objective is the investigation of the bonding mechanisms and the failure mechanisms determined by the manufacturing chain, while producing all-ceramic restorations. The influence of the components material properties on the bond strength will be evaluated. Following the chain of production, the effects and interactions of the production processes on the surface and subsurface properties of both bonding partners will be determined. Concluding, an empirical model is build. After validity of the model the results are transferred to stylized restorations. The empirical model describes the bond strength of the system based on material properties and parameters of the production process. Following the manufacturing and machining strategy will by adapted to increase the lifetime of all-ceramic restorations.

• DFG Programme: Research Grants