Chung Hyunsook, Kim Miri, Ko Hyunjung, Yang Wonkyung
Department of Conservative Dentistry, CHA Bundang Medical Center, CHA University, Gyeonggi-do, Korea.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011 Nov;112(5):e6-11. doi: 10.1016/j.tripleo.2011.04.005. Epub 2011 Jul 20.
This study examined whether 4-methacryloxyethyl trimellitate anhydride/methylmethacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin can be used with mineral trioxide aggregate (MTA) to overcome MTA's shortcomings. The biologic reactions of the mixture of MTA powder and 4-META/MMA-TBB resin (MTA/4-META) and its potential in clinical applications were also investigated.
MTA powder was mixed with 4-META/MMA-TBB resin instead of water at the appropriate proportions determined by a series of studies prior to this experiment. MTA powder mixed with sterile water was used as control. The setting time, compressive strength, pH, and dye leakage of MTA/4-META and MTA were assessed by Gilmore apparatus, universal mechanical testing machine, pH meter, and methylene blue penetration method, respectively. Cytotoxicity also was evaluated by MTT assay with MC3T3-E1 cells.
The setting time of MTA/4-META was significantly lower than that of MTA: 11.2 ± 0.8 minutes versus 318 ± 56.0 minutes, respectively (P < .05). The mean compressive strength of MTA/4-META after 24 hours was significantly higher than that of MTA: 57.4 ± 11.6 MPa versus 18.7 ± 3.0 MPa, respectively (P < .05). MTA/4-META showed significantly less leakage than MTA (P < .05). The initial pHs for MTA and MTA/4-META at 2 hours were 10.73 ± 0.95 and 10.08 ± 0.13, respectively, and reached plateaus of 10.92 ± 0.31 and 10.54 ± 0.39 at 24 hours, respectively. The pH of MTA was higher than that of MTA/4-META in the entire period, but the differences were only significant up to 48 hours (P < .05). MTA and MTA/4-META both showed no cytotoxicity.
4-META/MMA-TBB resin as a mixing vehicle of MTA powder can improve the setting and handling properties of MTA and may maintain or improve its other biophysical properties.
本研究探讨4-甲基丙烯酰氧乙基偏苯三酸酐/甲基丙烯酸甲酯-三正丁基硼烷(4-META/MMA-TBB)树脂是否可与矿物三氧化物凝聚体(MTA)配合使用以克服MTA的缺点。还研究了MTA粉末与4-META/MMA-TBB树脂混合物(MTA/4-META)的生物学反应及其在临床应用中的潜力。
在本实验之前通过一系列研究确定合适比例,将MTA粉末与4-META/MMA-TBB树脂混合而非与水混合。将MTA粉末与无菌水混合作为对照。分别用吉尔摩仪、万能材料试验机、pH计和亚甲蓝渗透法评估MTA/4-META和MTA的凝固时间、抗压强度、pH值和染料渗漏情况。还用MC3T3-E1细胞通过MTT法评估细胞毒性。
MTA/4-META的凝固时间显著低于MTA:分别为11.2±0.8分钟和318±56.0分钟(P<.05)。24小时后MTA/4-META的平均抗压强度显著高于MTA:分别为57.4±11.6MPa和18.7±3.0MPa(P<.05)。MTA/4-META的渗漏显著少于MTA(P<.05)。MTA和MTA/4-META在2小时时的初始pH值分别为10.73±0.95和10.08±0.13,在24小时时分别达到10.92±0.31和10.54±0.39的平稳值。在整个时间段内MTA的pH值高于MTA/4-META,但仅在48小时内差异显著(P<.05)。MTA和MTA/4-META均未显示细胞毒性。
4-META/MMA-TBB树脂作为MTA粉末的混合媒介可改善MTA的凝固和操作性能,并可能维持或改善其其他生物物理性能。