Effect of airborne-particle abrasion of presintered zirconia on surface roughness and bacterial adhesion.
BACKGROUND
Factors associated with implant periodontal disease of zirconia restorations such as surface roughness remain largely unknown.


OBJECTIVE
The purpose of this study was to investigate how airborne-particle abrasion before sintering affects roughness and bacterial adhesion on the surface of zirconia.


METHODS
Thirty presintered zirconia specimens were divided into 6 groups of 5 after being polished with silicon carbide paper (1200 grit). A different surface treatment was applied to each group (no treatment [group Ct] and 120-μm alumina abrasion for 5, 8, 10, 12, and 15 seconds [A5s, A8s, A10s, A12s, and A15s]), and the specimens were then densely sintered. The mean centric linear roughness (Ra) was measured, and the 3D measurement of surface roughness (3D roughness) was determined. The number of colony forming units (CFUs) of Streptococcus mutans adhering to the surface was also examined. One-way ANOVA was used for data analysis (α=.05).


RESULTS
Airborne-particle abrasion before sintering significantly increased surface roughness. Group A8s, A10s, A12s, and A15s showed statistically significant higher CFU/mL than did group A5s (P<.05). No difference was found in CFU/mL between group Ct and A5s (P=.230).


CONCLUSIONS
Airborne-particle abrasion before sintering is a useful method of increasing the surface roughness of zirconia. Ra < 0.58 μm is necessary to inhibit the adherence of S. mutans to zirconia.
Postgraduate student, Capital Medical University School of Stomatology, Beijing, PR China.
Ming
M
Zhang
Professor, Capital Medical University School of Stomatology, Beijing, PR China.
Zutai
Z
Zhang
Technician, Capital Medical University School of Stomatology, Beijing, PR China.
Ning
N
Ding
Professor, Capital Medical University School of Stomatology, Beijing, PR China. Electronic address: zhengdxg@163.com.
Dongxiang
D
Zheng
D000537:Aluminum Oxide / Q000737:chemistry; D001422:Bacterial Adhesion / Q000502:physiology*; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D045662:Dental Etching / Q000379:methods*; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000379:methods; D006358:Hot Temperature; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008422:Materials Testing; D011312:Pressure; D017655:Silicon Compounds / Q000737:chemistry; D013295:Streptococcus mutans / Q000502:physiology*; D013499:Surface Properties; D013997:Time Factors; D015040:Zirconium / Q000737:chemistry*
D017554:Carbon Compounds, Inorganic; D003764:Dental Materials; D017655:Silicon Compounds; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide; C022088:silicon carbide