Open Access
CC BY 4.0 · Eur J Dent 2023; 17(04): 1020-1028
DOI: 10.1055/s-0042-1757910
Original Article

Substrate Rigidity Effect on CAD/CAM Restorations at Different Thicknesses

1   Department of Restorative Dentistry, Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, Brazil
,
1   Department of Restorative Dentistry, Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, Brazil
,
1   Department of Restorative Dentistry, Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, Brazil
,
2   Department of Dentistry, Universidade Estadual do Oeste do Paraná (UNIOESTE), Cascavel, Brazil
,
3   Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands
,
3   Department of Dental Materials Science, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands
,
4   Department of Oral Regenerative Medicine, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands
› Institutsangaben
Preview

Abstract

Objectives This article evaluated the effect of substrates rigidities on the post-fatigue fracture resistance of adhesively cemented simplified restorations in lithium disilicate glass ceramic.

Methods Precrystalized computer-aided design/computer-aided manufacturing ceramic blocks were processed into disc-shaped specimens (n = 10, Ø = 10 mm), mimicking a simplified restoration at two thicknesses (0.5 and 1.0 mm). Thereafter, the discs were cemented onto different base substrates (dentin analogue [control], dentin analogue with a central core build-up of resin composite [RC], or glass ionomer cement [GIC]). The specimens were subjected to mechanical cycling in a chewing simulator (100 N, 1 × 106 cycles, 4 Hz) and then subjected to thermocycling aging (10,000 cycles, 5/37/55°C, 30 seconds). After the fatigue protocol, the specimens were loaded until failure (N) in a universal testing machine. Finite element analysis calculated the first principal stress at the center of the adhesive interface.

Results The results showed that “restoration thickness,” “type of substrate,” and their interaction were statistically significant (one-way analysis of variance; p < 0.001). Regardless the restoration thickness a higher fracture load was observed for specimens cemented to dentin analogue. Among the base materials, RC build-up presented the highest fracture load and lower stress magnitude for both restoration thicknesses in comparison with GIC build-up. The 0.5-mm restoration showed higher stress peak and lower fracture load when submitted to the compressive test.

Conclusion More flexible base material reduces the fracture load and increases the stress magnitude of adhesively cemented lithium disilicate restorations regardless the ceramic thickness. Therefore, more rigid substrates are suggested to be used to prevent restoration mechanical failures.

Authors' Contributions

C.R.P.: Conception and design, acquisition of data, analysis and interpretation of data, drafting the article, and final approval.


A.P.V.P.M.: Conception and design, acquisition of data, drafting the article, and final approval.


A.L.S.B.: Conception and design, acquisition of data, drafting the article, and final approval.


G.S.d.A.: Acquisition of data, drafting the article, revising the article, and final approval.


A.M.d.O.D.P.: Analysis and interpretation of data, drafting the article, revising the article, and final approval.


C.J.K.: Analysis and interpretation of data, drafting the article, revising the article, and final approval.


J.P.M.T.: Conception and design, acquisition of data, analysis and interpretation of data, drafting the article, revising the article, and final approval.




Publikationsverlauf

Artikel online veröffentlicht:
13. Dezember 2022

© 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India