Research/Technical Note | | Peer-Reviewed

Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study

Received: 19 May 2025     Accepted: 30 May 2025     Published: 30 January 2026
Views:       Downloads:
Abstract

Introduction: For a long time now, the majority of conventional complete denture bases have been made from acrylic resins. Conventional PMMA-based acrylic resins have remained firmly established in our practice because of their many qualities. Dentistry's entry into the era of computer-assisted design and manufacture (CAD/CAM) has offered prosthetic solutions adapted to a wide range of situations and has led to gains in precision, reproducibility and time. This work is an experimental study that investigates the microscopic structure and mechanical behaviour of two groups of acrylic resin intended for the manufacture of total dentures, while focusing on the salivary action on both types. Materials & Methods: The experiment was carried out in 3 successive stages: The first stage involved analysing the samples under a scanning electron microscope and evaluating their mechanical behaviour in terms of hardness and tensile strength. The second stage consisted of soaking the samples in artificial saliva according to a protocol described in the literature. The third stage involved carrying out the same types of analysis (SEM and mechanical) on the soaked samples. Results: Scanning electron microscope images of conventional PMMA were marked by the presence of black dots of different intensities and diameters ranging from 1 to 10 μm. They are of considerable number and occupy a large surface area in the observed sample. The image revealed spots of high opacity in places. The images were clustered and the domains are randomly oriented. The CAD/CAM images were characterised by the presence of a few black dots of varying intensities, most of which were no more than 3 μm in diameter. Other scattered dots show high opacity with band-like texturing. In the mechanical tensile test, we can say that PMMA - Conventional has better elongation and better plastic deformation, and is therefore better able to absorb external stresses, due to its high elongation capacity. On the other hand, the mechanical strength is lower than that of PMMA - CAD/CAM. The latter has higher mechanical strength but low elongation. Conclusion: This study highlights the potential benefits of CAD/CAM resins in terms of microscopic quality and mechanical strength, suggesting their advantageous use in dental prosthetics. However, long-term clinical studies are needed to validate their clinical suitability and durability.

Published in American Journal of Health Research (Volume 14, Issue 1)
DOI 10.11648/j.ajhr.20261401.16
Page(s) 40-47
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2026. Published by Science Publishing Group

Keywords

PMMA CAD-CAM, PMMA-conventional, Microscopy, Mechanical Properties

References
[1] Mubaraki MQ, Moaleem MMA, Alzahrani AH, Shariff M, Alqahtani SM, Porwal A, et al. Assessment of Conventionally and Digitally Fabricated Complete Dentures: A Comprehensive Review. Materials. 28 mai 2022; 15(11): 3868.
[2] Banerjee S, Jha S, Singh R, Shahi H, Arya A, Raj R. Flexural Strength of Different Commercially Available Auto-Polymerizing Acrylic Resins: An In Vitro Study. Cureus. 16(10): e71905.
[3] Zafar MS. Prosthodontic Applications of Polymethyl Methacrylate (PMMA): An Update. Polymers. 8 oct 2020; 12(10): 2299.
[4] Gad MM, Alshehri SZ, Alhamid SA, Albarrak A, Khan SQ, Alshahrani FA, et al. Water Sorption, Solubility, and Translucency of 3D-Printed Denture Base Resins. Dent J. 9 mars 2022; 10(3): 42.
[5] Helal MA, Fadl-Alah A, Baraka YM, Gad MM, Emam ANM. In-vitro Comparative Evaluation for the Surface Properties and Impact Strength of CAD/CAM Milled, 3D Printed, and Polyamide Denture Base Resins. J Int Soc Prev Community Dent. 29 janv 2022; 12(1): 126‑31.
[6] De Sá J, Vieira F, Aroso CM, Cardoso M, Mendes JM, Silva AS. The Influence of Saliva pH on the Fracture Resistance of Three Complete Denture Base Acrylic Resins. Int J Dent. 1 nov 2020; 2020: 8941876.
[7] Onwubu SC, Mdluli PS. Comparative Analysis of Abrasive Materials and Polishing System on the Surface Roughness of Heat-Polymerized Acrylic Resins. Eur J Dent. 10 déc. 2021; 16(3): 573‑9.
[8] Alzaid M, AlToraibily F, Al-Qarni FD, Al-Thobity AM, Akhtar S, Ali S, et al. The Effect of Salivary pH on the Flexural Strength and Surface Properties of CAD/CAM Denture Base Materials. Eur J Dent. 12 juill 2022; 17(1): 234‑41.
[9] Wang H, Li Y, Song D, Lin M, Guo X, Shi X. Mechanism and Model Analysis of Ultralow-Temperature Fluid Fracturing in Low-Permeability Reservoir: Insights from Liquid Nitrogen Fracturing. Processes. Juin 2024; 12(6): 1117.
[10] Gad MM, Fouda SM, Abualsaud R, Alshahrani FA, Al-Thobity AM, Khan SQ, et al. Strength and Surface Properties of a 3D-Printed Denture Base Polymer. J Prosthodont Off J Am Coll Prosthodont. Juin 2022; 31(5): 412‑8.
[11] Fiore AD, Meneghello R, Brun P, Rosso S, Gattazzo A, Stellini E, et al. Comparison of the flexural and surface properties of milled, 3D-printed, and heat polymerized PMMA resins for denture bases: An in vitro study. J Prosthodont Res. 30 juill 2022; 66(3): 502‑8.
[12] Fouda SM, Gad MM, Abualsaud R, Ellakany P, AlRumaih HS, Khan SQ, et al. Flexural Properties and Hardness of CAD-CAM Denture Base Materials. J Prosthodont Off J Am Coll Prosthodont. Avr 2023; 32(4): 318‑24.
[13] Baciu ER, Savin CN, Tatarciuc M, Mârțu I, Butnaru OM, Aungurencei AE, et al. Experimental Study on Mechanical Properties of Different Resins Used in Oral Environments. Medicina (Mex). 28 mai 2023; 59(6): 1042.
[14] Palacios T, Tarancón S, Abad C, Pastor JY. Saliva Influence on the Mechanical Properties of Advanced CAD/CAM Composites for Indirect Dental Restorations. Polymers. 6 mars 2021; 13(5): 808.
[15] Belli R, Wendler M, de Ligny D, Cicconi MR, Petschelt A, Peterlik H, et al. Chairside CAD/CAM materials. Part 1: Measurement of elastic constants and microstructural characterization. Dent Mater Off Publ Acad Dent Mater. Janv 2017; 33(1): 84‑98.
[16] Brożek R, Pałka K, Koczorowski R, Dorocka-Bobkowska B. Effect of artificial saliva on the mechanical properties of a polymer material reinforced with fiber, used in esthetic tooth restorations. Dent Med Probl. 2020; 57(3): 261-7.
[17] Srinivasan M, Kamnoedboon P, McKenna G, Angst L, Schimmel M, Özcan M, et al. CAD-CAM removable complete dentures: A systematic review and meta-analysis of trueness of fit, biocompatibility, mechanical properties, surface characteristics, color stability, time-cost analysis, clinical and patient-reported outcomes. J Dent. 1 Oct. 2021; 113: 103777.
Cite This Article
  • APA Style

    Hatim, A., Keita, M., Ghazi, H., Amadou, B. A., Mohaddib, F., et al. (2026). Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study. American Journal of Health Research, 14(1), 40-47. https://doi.org/10.11648/j.ajhr.20261401.16

    Copy | Download

    ACS Style

    Hatim, A.; Keita, M.; Ghazi, H.; Amadou, B. A.; Mohaddib, F., et al. Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study. Am. J. Health Res. 2026, 14(1), 40-47. doi: 10.11648/j.ajhr.20261401.16

    Copy | Download

    AMA Style

    Hatim A, Keita M, Ghazi H, Amadou BA, Mohaddib F, et al. Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study. Am J Health Res. 2026;14(1):40-47. doi: 10.11648/j.ajhr.20261401.16

    Copy | Download

  • @article{10.11648/j.ajhr.20261401.16,
      author = {Asmaa Hatim and Mory Keita and Hourya Ghazi and Barry Alpha Amadou and Fatima Mohaddib and Hassan Hannach},
      title = {Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study},
      journal = {American Journal of Health Research},
      volume = {14},
      number = {1},
      pages = {40-47},
      doi = {10.11648/j.ajhr.20261401.16},
      url = {https://doi.org/10.11648/j.ajhr.20261401.16},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajhr.20261401.16},
      abstract = {Introduction: For a long time now, the majority of conventional complete denture bases have been made from acrylic resins. Conventional PMMA-based acrylic resins have remained firmly established in our practice because of their many qualities. Dentistry's entry into the era of computer-assisted design and manufacture (CAD/CAM) has offered prosthetic solutions adapted to a wide range of situations and has led to gains in precision, reproducibility and time. This work is an experimental study that investigates the microscopic structure and mechanical behaviour of two groups of acrylic resin intended for the manufacture of total dentures, while focusing on the salivary action on both types. Materials & Methods: The experiment was carried out in 3 successive stages: The first stage involved analysing the samples under a scanning electron microscope and evaluating their mechanical behaviour in terms of hardness and tensile strength. The second stage consisted of soaking the samples in artificial saliva according to a protocol described in the literature. The third stage involved carrying out the same types of analysis (SEM and mechanical) on the soaked samples. Results: Scanning electron microscope images of conventional PMMA were marked by the presence of black dots of different intensities and diameters ranging from 1 to 10 μm. They are of considerable number and occupy a large surface area in the observed sample. The image revealed spots of high opacity in places. The images were clustered and the domains are randomly oriented. The CAD/CAM images were characterised by the presence of a few black dots of varying intensities, most of which were no more than 3 μm in diameter. Other scattered dots show high opacity with band-like texturing. In the mechanical tensile test, we can say that PMMA - Conventional has better elongation and better plastic deformation, and is therefore better able to absorb external stresses, due to its high elongation capacity. On the other hand, the mechanical strength is lower than that of PMMA - CAD/CAM. The latter has higher mechanical strength but low elongation. Conclusion: This study highlights the potential benefits of CAD/CAM resins in terms of microscopic quality and mechanical strength, suggesting their advantageous use in dental prosthetics. However, long-term clinical studies are needed to validate their clinical suitability and durability.},
     year = {2026}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Comparison of the Effect of Saliva on the Mechanical Properties and Microscopic Profile of Cad/Cam and Conventional Resins: Experimental Study
    AU  - Asmaa Hatim
    AU  - Mory Keita
    AU  - Hourya Ghazi
    AU  - Barry Alpha Amadou
    AU  - Fatima Mohaddib
    AU  - Hassan Hannach
    Y1  - 2026/01/30
    PY  - 2026
    N1  - https://doi.org/10.11648/j.ajhr.20261401.16
    DO  - 10.11648/j.ajhr.20261401.16
    T2  - American Journal of Health Research
    JF  - American Journal of Health Research
    JO  - American Journal of Health Research
    SP  - 40
    EP  - 47
    PB  - Science Publishing Group
    SN  - 2330-8796
    UR  - https://doi.org/10.11648/j.ajhr.20261401.16
    AB  - Introduction: For a long time now, the majority of conventional complete denture bases have been made from acrylic resins. Conventional PMMA-based acrylic resins have remained firmly established in our practice because of their many qualities. Dentistry's entry into the era of computer-assisted design and manufacture (CAD/CAM) has offered prosthetic solutions adapted to a wide range of situations and has led to gains in precision, reproducibility and time. This work is an experimental study that investigates the microscopic structure and mechanical behaviour of two groups of acrylic resin intended for the manufacture of total dentures, while focusing on the salivary action on both types. Materials & Methods: The experiment was carried out in 3 successive stages: The first stage involved analysing the samples under a scanning electron microscope and evaluating their mechanical behaviour in terms of hardness and tensile strength. The second stage consisted of soaking the samples in artificial saliva according to a protocol described in the literature. The third stage involved carrying out the same types of analysis (SEM and mechanical) on the soaked samples. Results: Scanning electron microscope images of conventional PMMA were marked by the presence of black dots of different intensities and diameters ranging from 1 to 10 μm. They are of considerable number and occupy a large surface area in the observed sample. The image revealed spots of high opacity in places. The images were clustered and the domains are randomly oriented. The CAD/CAM images were characterised by the presence of a few black dots of varying intensities, most of which were no more than 3 μm in diameter. Other scattered dots show high opacity with band-like texturing. In the mechanical tensile test, we can say that PMMA - Conventional has better elongation and better plastic deformation, and is therefore better able to absorb external stresses, due to its high elongation capacity. On the other hand, the mechanical strength is lower than that of PMMA - CAD/CAM. The latter has higher mechanical strength but low elongation. Conclusion: This study highlights the potential benefits of CAD/CAM resins in terms of microscopic quality and mechanical strength, suggesting their advantageous use in dental prosthetics. However, long-term clinical studies are needed to validate their clinical suitability and durability.
    VL  - 14
    IS  - 1
    ER  - 

    Copy | Download

Author Information
  • Departement of Removable Prosthodontics, Mohammed VI University of Sciences and Health, Casablanca, Morocco;Dental Sciences Research Laboratory, Mohammed VI University of Sciences and Health, Casablanca, Morocco

  • Departement of Removable Prosthodontics, Mohammed VI University of Sciences and Health, Casablanca, Morocco;Dental Sciences Research Laboratory, Mohammed VI University of Sciences and Health, Casablanca, Morocco

  • Departement of Removable Prosthodontics, Mohammed VI University of Sciences and Health, Casablanca, Morocco;Dental Sciences Research Laboratory, Mohammed VI University of Sciences and Health, Casablanca, Morocco

  • Departement of Removable Prosthodontics, Mohammed VI University of Sciences and Health, Casablanca, Morocco;Dental Sciences Research Laboratory, Mohammed VI University of Sciences and Health, Casablanca, Morocco

  • Private Practitioner, Casablanca, Morocco

  • Department of Materials Science, Energy, and Nanotechnology, Mohammed VI Polytechnic University, Benguerir, Morocco

  • Sections