Dental Ceramics — MFDS Part 1 MCQ

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ModerateDental MaterialsDental CeramicsMFDS Part 1

For a porcelain-veneered all-ceramic crown, which of the following dental ceramics provides the highest-strength core or framework?

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Correct answer: E — Yttria-stabilised zirconia

Yttria-stabilised zirconia is the correct answer. Its polycrystalline structure provides high flexural strength and fracture toughness. Stress-induced tetragonal-to-monoclinic transformation around a developing crack contributes to transformation toughening and resistance to crack propagation. It can therefore be used as the supporting framework for porcelain-veneered all-ceramic restorations. Feldspathic, leucite-reinforced and fluormica ceramics contain a substantial glass phase and offer useful optical properties but lower strength. Alumina-reinforced ceramic can also be used as a core material, making it the principal distractor, but it is less strong and tough than Y-TZP. A universal value of 900–1200 MPa should not be stated because zirconia strength varies with yttria content, processing, surface treatment and test method.

Reference: Bernauer SA et al. Flexural strength of translucent zirconia for single crowns and fixed dental prostheses—A systematic review. Journal of Prosthodontic Research. 2026. https://pubmed.ncbi.nlm.nih.gov/40738693/