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. 2025 May 25;25(1):793.
doi: 10.1186/s12903-025-05889-4.

Marginal fit and fracture resistance of CAD/CAM glass ceramic occlusal veneers with different preparation designs

Suad M Hassan  1 , Ayat G Montaser  1 , Zinab R El Sharkawy  1 , Nevin A Gad  2 , Shaimaa A Alrafee  3 , Zahraa A Gabal  1
Affiliations

Marginal fit and fracture resistance of CAD/CAM glass ceramic occlusal veneers with different preparation designs

Suad M Hassan et al. BMC Oral Health. .

Abstract

Background: To assess marginal fit and fracture resistance of CAD/CAM glass ceramic occlusal veneers with different preparation designs.

Methods: First premolar typodont maxillary was chosen. Standard IPS E.max CAD occlusal veneer preparations were carried out using Exocad software using three distinct designs: the first design involved a minimally invasive preparation (butt joint"BJ"group); the second design involved an occlusal veneer preparation with a circumferential hollow chamfer finish line"HC"group; and the third design involved a deep chamfer finish line"DC"group. To create a total of 24 epoxy resin replicas, each prepared design was reproduced eight times ("n = 8"for each prepared design). Every sample was made using IPS E.max CAD ceramics. Every occlusal veneer was firmly attached to the matching epoxy resin using adhesive resin cement. A computerized stereomicroscope was used to measure the vertical marginal gap. Ultimately, the fracture resistance was measured using a universal testing apparatus.

Results: Deep chamfer occlusal veneer design, group"DC", registered statistically significant the highest mean value of vertical marginal gap (118.38 ± 10.43 μm) as well as the lowest mean value of failure load (549.97 ± 56.66 N). While butt joint occlusal veneer design"BJ"registered a statistically significant lowest mean value of vertical marginal gap (99.2 ± 7.15 μm) as well as the highest mean value of failure load (1107.25 ± 93.09 N).

Conclusions: Although different preparation designs of IPS E.max CAD occlusal veneer restorations would significantly affect the marginal fit and fracture resistance, all groups were within the clinically accepted range.

Keywords: Different preparation designs; Fracture resistance; IP E.max CAD; Marginal fit; Occlusal veneer.

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Conflict of interest statement

Declarations. Ethics approval and consent to participate: The Research Ethics Committee (REC) et al.-Azhar University's Faculty of Dental Medicine for Girls gave its approval to this study under Code (P-PD- 24–13). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Occlusal veneer preparation designs; a Butt joint design. b Hollow chamfer design. c Proposed modified design
Fig. 2
Fig. 2
Manufacturing and duplication of epoxy resin dies; A Prepared 3D-printed butt joint design embedded in epoxy resin. B Prepared 3D-printed hollow chamfer design embedded in epoxy resin. C Prepared 3D-printed proposed modified design embedded in epoxy resin. D Epoxy resin dies for butt joint design. E Epoxy resin dies for hollow chamfer design. F Epoxy resin dies for proposed modified design
Fig. 3
Fig. 3
Bar chart illustrating mean marginal fit in different preparation designs used for the fabrication of occlusal veneers
Fig. 4
Fig. 4
Digital microscopic images of vertical marginal gap distance at different occlusal veneer designs; A Butt joint design. B Hollow chamfer design. C Proposed modified design
Fig. 5
Fig. 5
Bar chart illustrating mean fracture resistance in different preparation designs used for the fabrication of occlusal veneers
Fig. 6
Fig. 6
Failure mode; A Occlusal veneer fracture through midline (half of the veneer is displaced or lost) (Code III). B Fracture of more than half of the occlusal veneers (Code IV). C, D Sever fracture of epoxy resin die or occlusal veneer (Code V)
Fig. 7
Fig. 7
Bar chart illustrating mode of failure between groups
Fig. 8
Fig. 8
Scatter plot showing correlation between fracture resistance and marginal fit
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References

    1. Falahchai M, Babaee Y, Neshandar H, Rezaei E. Effect of tooth preparation design on fracture resistance of zirconia-reinforced lithium silicate overlays. Prosthodont J. 2020;29:617–22. - PubMed
    1. Kasem A, Sakrana A, Ellayeh M, Özcan M. Evaluation of zirconia and zirconia-reinforced glass ceramic systems fabricated for minimal invasive preparations using a novel standardization method. Esthet Restor Dent J. 2020;32:560–8. - PubMed
    1. Salah M, Halim CH, Nabil O. Marginal accuracy of CAD/CAM occlusal veneers fabricated from glass and hybrid ceramics with two preparation designs: An in vitro study. Int J Appl Dent Sci. 2023;9:93–100.
    1. Sirous S, Navadeh A, Ebrahimgol S, Atri F. Effect of preparation design on marginal adaptation and fracture strength of ceramic occlusal veneers: a systematic review. Clin Exp Dent Res J. 2022;8:1391–403. - PMC - PubMed
    1. Hashem R. Marginal fit and fracture resistance of advanced lithium disilicate occlusal veneer with different preparation designs. Egy Dent J. 2023;69:2115–25.

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