Digital advancements have transformed the fabrication of dental prostheses. Specifically, 3D printing offers speed and accuracy for denture bases. However, practitioners must understand that 3D printing orientation alters the surface topography of the final product. Recent evidence suggests that the angle of layer deposition directly affects how easily bacteria and fungi can colonize the material.

Surface Properties and Microbial Adhesion

The study evaluated FotoDent® resin at three printing angles: 0°, 45°, and 90°. Interestingly, the results showed that microbial counts for Candida albicans, Porphyromonas gingivalis, and Streptococcus mutans decreased as the print angle increased. Specifically, the 90-degree angle demonstrated the lowest microbial adhesion across all species. In contrast, the 0-degree orientation produced the highest surface roughness. Furthermore, these 3D-printed specimens generally outperformed conventional cold-cured resins in resisting microbial colonization.

Advantages of 90-degree 3D Printing Orientation

Using a 90-degree 3D printing orientation provides a smoother surface finish compared to horizontal printing. This smoother texture minimizes the niches available for microbial entrapment. Consequently, dentures printed at this angle may lower the risk of denture stomatitis and periodontal issues. Therefore, clinicians should specify optimal printing parameters when ordering digitally fabricated prostheses. Additionally, this choice helps maintain long-term oral health by simplifying the cleaning process for the patient.

Clinical Recommendations for Digital Dentures

While 3D printing is efficient, the technical settings dictate the biological response of the oral tissues. Practitioners should favor orientations that reduce areal surface roughness. Moreover, the study indicates that surface free energy components change with the printing angle. This variation impacts how the material interacts with saliva and oral microbes. Ultimately, selecting the 90-degree orientation offers a superior balance of surface smoothness and reduced microbial load.

Frequently Asked Questions

Which printing orientation is best for denture hygiene?

A 90-degree printing orientation is superior because it produces the smoothest surface and significantly reduces microbial adhesion compared to 0-degree and 45-degree angles.

How does the printing angle affect surface roughness?

The 0-degree printing orientation typically yields the highest surface roughness. As the angle increases toward 90 degrees, the surface becomes smoother, which limits biofilm formation.

Are 3D-printed resins better than conventional cold-cured resins?

Yes, the study found that FotoDent® 3D-printed resin generally exhibited lower microbial counts than conventional cold-cured ProBase® resins, suggesting better biological performance.

Disclaimer: This content is for informational and educational purposes only. It does not constitute medical advice or a professional endorsement. Clinicians should use their professional judgment and consider individual patient factors when making treatment decisions. Refer to the latest local and national guidelines for clinical practice.

References

Akbar JH et al. Impact of Printing Orientation on the Surface Properties and Microbial Biofilm Formation of 3D-Printed Denture Resins. Int J Prosthodont. 2026 Jun 02. doi: 10.11607/ijp.9754. PMID: 42234481.

Al-Haj Husain N et al. Effect of printing orientation on the surface and mechanical properties of 3D-printed denture base resins: A systematic review. J Prosthet Dent. 2023.