Effect of Polishing on Surface Roughness and Bacterial Adhesion of Prefabricated Zirconia and Fiber Pediatric Crowns: An In vitro Study

OpenAlex · İngilizce

BACKGROUND: Prefabricated zirconia crowns (PZCs) and prefabricated fiber crowns (PFCs) are increasingly used as esthetic restorative options for extensively carious primary teeth, driven by rising esthetic demands. AIM: This study aimed to compare the surface roughness, topography, and biofilm formation of PZCs and PFCs before and after polishing procedures. MATERIALS AND METHODS: Sixty anterior crowns (24 PZCs, 36 PFCs) were sectioned into 5 mm × 5 mm samples, divided into five groups. Group 1: PFCs with no surface treatment; Group 2: PFCs roughened with a bur and polished using a one-step system; Group 3: PFCs polished with a multi-step disc system; Group 4: PZCs with no surface treatment; Group 5: PZCs polished using zirconia polishing rubbers. Surface roughness was evaluated using a profilometer, surface topography with an atomic force microscope, and micro-surface morphology with scanning electron microscopy. Polymicrobial biofilms were developed on the sample surfaces, and colony counts were performed for total bacteria, Streptococcus mutans , and Streptococcus mitis . RESULTS: PZCs exhibited significantly lower surface roughness values than PFCs ( P < 0.05). Roughness decreased after polishing in all groups. Bacterial adhesion correlated with roughness, with the lowest colony counts observed in polished PZCs. Polishing did not significantly alter PZCs, whereas PFCs showed a marked reduction in surface roughness. CONCLUSIONS: PZCs may provide clinical advantages due to their smoother surfaces and lower bacterial adhesion. Appropriate polishing protocols for PFCs can also reduce surface roughness and bacterial colonization, improving their clinical performance.