d e n t a l m a t e r i a l s 2 9 ( 2 0 1 3 ) 626–634 Available online at www.sciencedirect.com jo ur nal ho me pag e: www.intl.elsevierhealth.com/journals/dema Endodontic access cavity simulation in ceramic dental crowns Mitchell Cuddihy a , Catherine M. Gorman b , Francis M. Burke c , Noel J. Ray c , Denis Kelliher d,∗ a Department of Materials, Royal School of Mines, Imperial College London, London SW7 2AZ, United Kingdom b Restorative Dentistry and Periodontology, Trinity College Dublin, Dublin 2, Ireland c Restorative Dentistry, Cork University Dental School and Hospital, University College Cork, Ireland d Department of Civil and Environmental Engineering, University College Cork, Ireland a r t i c l e i n f o Article history: Received 28 March 2012 Received in revised form 14 December 2012 Accepted 4 March 2013 Keywords: Finite element analysis Simulation Endodontics Restorative dentistry a b s t r a c t Objectives. It is proposed that a non-uniform rational B-spline (NURBS) based solid geometric model of a ceramic crown would be a flexible and quick approach to virtually simulate root canal access cavities. The computation of strain components orthogonal to surface flaws generated during the drilling would be an appropriate way of comparing different access cavity configurations. Methods. A CT scan is used to develop a full 3D NURBS geometric solid model of a ceramic crown. Three different access cavity configurations are created virtually in the geometric model and there are then imported into proprietary finite element software. A linear analysis of the each crown is carried out under appropriate in vivo loading and the results are post- processed to carry out a quantitative comparison of the three configurations Results. The geometric model is shown to be a flexible and quick way of simulation access cavities. Preliminary indications are that post processed strain results from the finite ele- ment analysis are good comparators of competing access cavity configurations. Significance. The generation of geometric solid models of dental crowns from CT scans is a flexible and efficient methodology to simulate a number of access cavity configura- tions. Furthermore, advanced post-processing of the primary finite element analysis results is worthwhile as preliminary results indicate that improved quantitative comparisons between different access cavity configurations are possible. © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. 1. Introduction Classical structural mechanics fails to produce an adequate elucidation of the stresses and strains developed in a system as geometrically complex as a grinding tooth. Naturally, the boundary of such a surface cannot be described by a singu- lar component such as a beam or a plate, and therefore a ∗ Corresponding author. Tel.: +353 21 490 2308. E-mail address: d.kelliher@ucc.ie (D. Kelliher). computer simulation must be carried out. All physical phenomena are modeled mathematically as partial differen- tial equations. It is rare that the solutions for these partial differential equations are trivial [1], but since the development of the computer, numerical solutions are now mainstream. For boundary value field problems, including structural mechan- ics, the finite element method (FEM) is the standard numerical approach. The ability of the FEM to accurately compute stress 0109-5641/$ – see front matter © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.dental.2013.03.001