SimuCrown: Simulation of functional aging – towards failure prediction of dental restorations

• Applicants: Professor Dr. Florian Beuer; Professorin Dr.-Ing. Claudia Fleck; Dr. Andreas Kupsch, since 6/2023; Professor Dr. Paul Zaslansky
• Subject Area: Dentistry, Oral Surgery
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 511983950

Full-coverage dental crowns are clinically recommended for restoring teeth with significant tissue loss and are the most common indirect dental restoration in Germany. The cementation of the dental crown restoration establishes a crown-cement-tooth-complex (CCTC), containing a cement interphase between the internal surface of the artificial crown and the tooth abutment. The interactions between clinically observed complications, e.g. decementation, crown fracture or need for endodontic treatment, and how material aging processes due to clinical use affect teeth restored with dental crowns are poorly understood. Dynamic changes within the cement layer and degradation near the abutment interfaces internally or near crown materials externally are mostly unknown. We hypothesise that changes to the integrity of the cement layer due to aging are the major reason for failures of crown restorations. Using artificial tooth abutments produced by CAD/CAM procedures, large-scale series of specimen with a CCTC will be created. It is the aim to investigate how temporal changes in the cement layer structure influence the mechanical compliance and endurance of crown restorations. One focus is to determine to what extent cement layer dimensions and properties influence the loading capability of the CCTC. For this purpose, the CCTC will be imaged by non-destructive high-resolution and high-contrast absorption μCT. Furthermore, we intend to identify local mechanical strains and stresses within the cement interzone in relation to failure mechanisms of the CCTC. Finite element techniques will be used to determine the local mechanical strains within cement layer under simulated masticatory conditions. In a further working package, microstructural changes due to both thermal cycling and mechanical loading in a chewing simulator will be studied by using non-destructive imaging with high-resolution μCT. Finite element computer models will be converted into dynamic simulations of cement aging processes to account for changes in the structural and/or material properties of the cement layer. In conclusion, the purposeful combination of in vitro and in silico methods with non-destructive imaging by using μCT and 3D reconstruction software will allow us to explore the CCTC and to relate its time-dependent changes with failure scenarios.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Bernd Randolf Müller, until 6/2023