Comparative Evaluation of Effect of Surface Roughness on Microbial Adhesion to Milled, 3D‐Printed, and Conventional PMMA Denture Base Resin: An In Vitro Study
Jinsha Maji K., Sheejith M., Nivea Francis T.Purpose
This study investigates how surface roughness influences Candida albicans adhesion to denture base resins fabricated using milling, 3D printing, and heat polymerization.
Materials and Methods
Sixty polymethylmethacrylate (PMMA) disc specimens (10 mm diameter, 2 mm thickness) were prepared using three techniques: conventional heat‐cured PMMA, stereolithography (SLA)‐based 3D printing, and computer‐aided design and computer‐aided manufacturing (CAD‐CAM) milling ( n = 20 per group). Surface roughness (Ra, µm) was recorded using a contact profilometer at three points per specimen. C. albicans adherence was evaluated by applying a standardized fungal suspension and counting colony‐forming units (CFUs) after 24 h of incubation. Specimens were fixed in 3% glutaraldehyde and dehydrated in graded ethanol. Data were expressed as mean ± standard deviation and analyzed via one‐way ANOVA, with significance set at p ≤ 0.05.
Results
3D‐printed PMMA showed the highest roughness (Ra = 1.83 ± 0.428 µm), followed by conventional PMMA (Ra = 0.71 ± 0.111 µm), while milled PMMA had the lowest (Ra = 0.37 ± 0.060 µm). Differences were statistically significant ( p = 0.001). Similarly, C. albicans adhesion was highest on 3D‐printed PMMA (1321.5 ± 271.05 CFU/mL), followed by conventional PMMA (903.75 ± 70.02 CFU/mL), and lowest on milled PMMA (372.7 ± 184.50 CFU/mL), with significant intergroup differences ( p = 0.001). Post hoc LSD tests confirmed significance in all pairwise comparisons ( p < 0.05). These results suggest smoother surfaces—particularly from CAD‐CAM milling—reduce microbial colonization.
Conclusion
Fabrication method significantly influences C. albicans adhesion. CAD‐CAM milled PMMA demonstrated the least adherence due to its smoother surface, while 3D‐printed PMMA showed the highest due to surface irregularities. Surface roughness plays a crucial role, and CAD‐CAM milling appears most effective in minimizing fungal infection risk.