Current Research in Dentistry

Total Occlusal Convergence and Margin Design in Relation to Survival of Glass-Ceramic Crowns: A Review

Janine Tiu, J. Neil Waddell, Basil Al-Amleh and Michael V. Swain

DOI : 10.3844/crdsp.2014.10.16

Current Research in Dentistry

Volume 5, Issue 2

Pages 10-16


This review aims to report on preparation geometryparameters and their relation to crown failures in complete glass-ceramicclinical studies. A review of the literature was conducted in MEDLINE/PubMedwith an additional manual search. The articles were screened through aninclusion and exclusion criteria and information regarding the Total OcclusalConvergence (TOC) angle and margin design was extracted along with itssurvivability. Nineteen articles were found, three were retrospective studiesand 16 were prospective. Three articles specified TOC and 16 articles specifiedtheir margin design. Eighty failures were reported but lack of informationbetween core and margin design and failures meant the relationship wasinconclusive. There were a limited number of long-term clinical studiesassessing glass-ceramic complete crowns. These studies provided insufficientinformation regarding the TOC angles of the prepared crowns and its potentialeffect on the survivability of glass-ceramic crowns. Further studies need to beconducted to determine how the TOC and margin design can affect the survivalrates of glass-ceramic complete crowns.


© 2014 Janine Tiu, J. Neil Waddell, Basil Al-Amleh and Michael V. Swain. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.