Radiopacity and cytotoxicity of Portland cement containing zirconia doped bismuth oxide radiopacifiers.
BACKGROUND
This study evaluates the radiopacity and cytotoxicity of Portland cements containing a radiopacifier of bismuth oxide (Bi2O3) with yttria-stabilized zirconia (YSZ) dopant.


METHODS
Various radiopacifier powders of Bi2O3 with 0%, 15%, 30%, and 100% YSZ dopant were prepared by solid-state reaction at 700°C for 12 hours and characterized by x-ray diffraction. Portland cement/radiopacifier/calcium sulfate (75/20/5) were mixed and set by deionized water. Changes in radiopacity and in vitro cell viability of the hydrated cements were assessed. An average of 6 measured equivalent thickness of aluminum (N = 6) capable of producing similar radiographic density was recorded. The cytotoxicity of each material was determined in MC3T3 E1 cell-based methyl-thiazol-tetrazolium assay.


RESULTS
The x-ray diffraction patterns of YSZ doped Bi2O3 are different from those of pure Bi2O3 and YSZ. The cement-containing radiopacifier of Bi2O3/YSZ (85/15) presented significantly greater radiopacity (P < .05) compared with pure Bi2O3. The mouse osteoblastic cell (MC3T3-E1) viabilities of these 2 groups were statistically similar (P < .05).


CONCLUSIONS
The radiopacifier of Bi2O3/YSZ (85/15) reveals higher radiopacity but similar cell viability when compared with pure Bi2O3. It shows potential use as an alternative radiopacifier in root-end filling materials.
Division of Plastic Surgery, Department of Surgery, Taipei Medical University-Wan Fang Hospital, Taipei; Department of General Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei; Evidence-Based Medicine Center, Taipei Medical University-Wan Fang Hospital, Taipei; Center for Evidence-Based Medicine, Taipei Medical University, Taipei.
Chiehfeng
C
Chen
School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei.
Sung-Chih
SC
Hsieh
School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei.
Nai-Chia
NC
Teng
School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei.
Chih-Kuo
CK
Kao
School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei; Dental Department, Wan-Fang Hospital, Taipei Medical University, Taipei, Taiwan.
Sheng-Yang
SY
Lee
School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei. Electronic address: chungkweilin@gmail.com.
Chung-Kwei
CK
Lin
School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei. Electronic address: Yang820065@tmu.edu.tw.
Jen-Chang
JC
Yang
D016475:3T3 Cells; D017607:Aluminum Compounds / Q000737:chemistry* / Q000633:toxicity; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000633:toxicity; D001729:Bismuth / Q000737:chemistry* / Q000633:toxicity; D017610:Calcium Compounds / Q000737:chemistry* / Q000633:toxicity; D002133:Calcium Sulfate / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D002516:Ceramics / Q000737:chemistry; D004396:Coloring Agents; D003287:Contrast Media / Q000737:chemistry*; D004338:Drug Combinations; D006358:Hot Temperature; D008422:Materials Testing; D051379:Mice; D010006:Osteoblasts / Q000187:drug effects; D010087:Oxides / Q000737:chemistry* / Q000633:toxicity; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000633:toxicity; D017640:Silicates / Q000737:chemistry* / Q000633:toxicity; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry* / Q000633:toxicity; D015040:Zirconium / Q000737:chemistry* / Q000633:toxicity
D017607:Aluminum Compounds; D001672:Biocompatible Materials; D017610:Calcium Compounds; D004396:Coloring Agents; D003287:Contrast Media; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; D013778:Tetrazolium Salts; D013844:Thiazoles; C086631:mineral trioxide aggregate; C499362:yttria stabilized tetragonal zirconia; D015019:Yttrium; C033301:bismuth oxide; D015040:Zirconium; C022616:thiazolyl blue; D001729:Bismuth; D002133:Calcium Sulfate
Biocompatibility; mineral trioxide aggregate-like cement; radiopacity