Using Spectroscopy to Evaluate the Degradation of Dental Resin Composites

A recent study explored how Raman spectroscopy and Fourier transform infrared (FT-IR) can be used to study the structural integrity of dental resin composites. This study, which was published in the peer-reviewed journal Medicina, tested how some of the most popular acidic beverages can weaken dental resin composites (1). The findings of the study reveal important considerations for both clinicians and patients regarding the durability and longevity of dental treatments.

Dental resin composites are used in a variety of dental procedures. Besides cavity fillings, they can also be used to repair chipped or broken teeth (2). Dental resin composites could also match the coloring of a patient’s teeth, making them unnoticeable to the naked eye (2).

Wide view of dentist applying composite filling to a lower premolar of a female patient wearing protective glasses during treatment. | Image Credit: © Mdv Edwards - stock.adobe.com

In this study, the research team examined two widely used resin composites: G-ænial A’CHORD and Omnichroma. These materials are favored in restorative dentistry for their strong mechanical properties and aesthetic qualities (1). However, their long-term clinical performance is known to be influenced by exposure to dietary and environmental stressors. The research team investigated how sustained contact with acidic and pigmented beverages alters the microhardness and molecular stability of these composites (1).

As part of the experimental procedure, the team created 40 disk-shaped specimens, 20 of each composite. They divided them into four groups: control, coffee, red wine, and Coca-Cola. The specimens were immersed in their respective solutions for ten days. Following immersion, the samples were analyzed using Raman spectroscopy, FT-IR spectroscopy, and Vickers microhardness testing to measure chemical and mechanical changes (1).

The results indicated that both composites erode under consistent exposure to acidic and staining beverages. Omnichroma was found to be more vulnerable than G-ænial A’CHORD, displaying a greater susceptibility to softening under prolonged exposure (1). Red wine and coffee produced the most pronounced deterioration, suggesting that polyphenolic compounds and acidity strongly interact with the polymer–filler network of the composites (1).

The importance of using Raman and FT-IR spectroscopy was apparent in the study. By noticing the molecular-level changes, the researchers were able to point to alterations in polymer–matrix interactions and filler composition, supporting the observed reduction in mechanical hardness (1).

However, several limitations need to be mentioned. For one, this experiment was in vitro. This designation means that the controlled immersion conditions cannot fully replicate the complex oral environment, where saliva, bacterial biofilms, mastication forces, and temperature fluctuations all influence material degradation (1). The absence of saliva simulation in particular limits the applicability of the findings, as saliva naturally buffers pH changes and could modify beverage-induced effects (1).

The 10-day immersion period is also a limitation. Although 10 days could help indicate early-stage degradation, the fact remains that this short period does not fully reflect long-term exposure scenarios (1). Therefore, future work should look at extending the duration of testing and incorporating artificial aging processes to uncover more information about how these composites perform over time. The authors also called for expanding future studies to include a broader range of dental composites, such as nanocomposites, bulk-fill materials, and bioactive formulations, as well as testing with other beverages like fruit juices, energy drinks, and spirits (1).

As a result, this study highlights the importance of material selection in ensuring long-term restorative success. Understanding how different composites respond to dietary challenges can help clinicians make informed choices that extend the lifespan and aesthetics of restorations (1). Although resin composites offer significant aesthetic and functional advantages, their durability is not immune to everyday dietary habits (1).

Ultimately, the results from this study could help propel further research forward in building more resilient dental materials capable of withstanding the chemical and mechanical stresses of modern diets.

References

1. Dumitrescu, R.; Anghel, I.-M.; Opris, C.; et al. Investigating the Effect of Staining Beverages on the Structural and Mechanical Integrity of Dental Composites Using Raman, Fourier Transform Infrared (FTIR) Spectroscopy, and Microhardness Analysis. Medicina 2025, 61 (4), 590. DOI: 10.3390/medicina61040590
2. Larson, J. What You Should Know About Composite Fillings. Healthline. Available at: https://www.healthline.com/health/dental-and-oral-health/composite-fillings#:~:text=VIEW%20GALLERY4-,Takeaway,reviewed%20on%20July%2016%2C%202021 (accessed 2025-08-18).