We are using cookies to implement functions like login, shopping cart or language selection for this website. Furthermore we use Google Analytics to create anonymized statistical reports of the usage which creates Cookies too. You will find more information in our privacy policy.
OK, I agree I do not want Google Analytics-Cookies
The International Journal of Prosthodontics



Forgotten password?


Int J Prosthodont 28 (2015), No. 4     28. July 2015
Int J Prosthodont 28 (2015), No. 4  (28.07.2015)

Page 357-359, doi:10.11607/ijp.4191, PubMed:26218016

The Effects of Margin Curvature on Load at Fracture of Ceramic Crowns
Øilo, Marit / Kvam, Ketil / Reisegg, Kjetil / Gjerdet, Nils Roar
Purpose: Despite the high fracture strength of modern dental core ceramics, fractures are a common cause of clinical failures. The aim of this study was to use a clinically relevant test method to evaluate the effect of the curvature of the cervical crown margins on load at fracture.
Materials and Methods: Thirty zirconia crowns and 30 glass-ceramic crowns were produced for three premolar preparations with variation in the approximal crown margin curvature: low curvature (r = 12 mm), moderate curvature (r = 2.5 mm), and high curvature (r = 1.5). The crowns were loaded until fracture with a method that mimics clinical fracture modes.
Results: Statistically significant differences were found among both crown margin curvature and material groups (P < .001). Most fractures originated from pre-existing flaws.
Conclusion: A moderate to low curvature of the crown margins increases crown strength compared with a high curvature.