Current Oral Health Reports

, Volume 5, Issue 3, pp 163–168 | Cite as

Fracture Toughness Testing of Dental Restoratives: a Critical Evaluation

  • Renan BelliEmail author
  • José Ignácio Zorzin
  • Ulrich Lohbauer
Dental Restorative Materials (M Özcan, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Dental Restorative Materials


Purpose of Review

We intend by this short critical review to highlight important aspects regarding the mechanical testing of fracture toughness. The final aim is to increase the awareness to the test sensitivity, ultimately increasing the quality and reliability of reported testing results.

Recent Findings

In a well-intended attempt to facilitate testing procedures or provide alternatives for testing material interfaces, authors are resorting to adaptation of testing methodologies without proper theoretical and experimental validation. The assumption of validity in such cases endangers the perpetration of testing strategies that are not safeguarded by sound theoretical bases. The use of improper statistical treatments based on extreme-value distributions further aggravates this scenario.


We supply here some directions for authors concerning method selection, interpretation of data scatter, statistical treatment, and possibilities for test validation.


Dental restorative materials Mechanical properties Fracture toughness Testing 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Renan Belli
    • 1
    Email author
  • José Ignácio Zorzin
    • 1
  • Ulrich Lohbauer
    • 1
  1. 1.Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Zahnklinik 1 – Zahnerhaltung und Parodontologie, Forschungslabor für dentale BiomaterialienErlangenGermany

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