Calcium leaching from dentin and shear bond strength after etching with phosphoric acid of different concentrations.
Calcium leaching from dentin and shear bond strength after etching with phosphoric acid of different concentrations.
复制标题
牙本质钙的浸出及不同浓度磷酸酸蚀后的剪切结合强度。
DOI：
10.1034/j.1600-0722.2000.108003247.x
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Mondragon,E
中科院分区：
文献类型：
--
作者：
Jacobsen,T;Soderholm,KJ;Garcea,I;Mondragon,E
根据H2O-P2O5-CaO相图，我们假设27 wt%左右的磷酸浓度会浸出牙本质中的大部分钙。我们还假设粘结强度受树脂浸润的影响，当漏钙超过一定值时树脂浸润不完全。牙本质盘从人的磨牙上切下。制备了8种磷酸浓度（15.7 - 51.2% wt%）。每个酸组有4个蚀刻时间亚组（15、30、60和120 s）。牙本质盘在酸中蚀刻，在水中分别冲洗15 s、30 s、60 s和120 s。用原子吸收光谱法分析了钙的浓度。使用相同的蚀刻方法将复合圆柱体与牙齿的剩余部分结合，并确定剪切结合强度。29.2 wt%组钙浸出值最高，15.7 wt%组钙浸出值最低。尽管在较长的蚀刻时间内存在较低粘结强度的趋势，但仅在30秒和120秒之间发现了统计学上显著的差异。钙浸出与粘结强度无显著相关。结果支持已测试的假设，即最高浸出值约为27 wt%的磷酸。
Based on the H2O–P2O5–CaO phase diagram, we hypothesize that a phosphoric acid concentration around 27 wt% leaches most calcium from dentin. We also hypothesize that bond strength is affected by resin infiltration, and that resin infiltration becomes incomplete when calcium leakage exceeds a certain value. Dentin disks were cut from human molars. Eight phosphoric acid concentrations were prepared (15.7–51.2 wt%). For each acid group, there were four etch time subgroups (15, 30, 60 and 120 s). The dentin disks were etched in acid and rinsed in water for times corresponding to 15 s, 30 s, 60 s and 120 s. The calcium concentrations were analyzed using atomic absorption spectroscopy. Composite cylinders were bonded to the remaining parts of the teeth using the same etching protocol, and shear bond strength was determined. The 29.2 wt% group demonstrated the highest and the 15.7 wt% group the lowest calcium leaching value. Even though there were trends towards lower bond strength for longer etch times, a statistically significant difference was only found between 30 and 120 s. There was no significant correlation between calcium leaching and bond strength. The results support the tested hypothesis that the highest leaching value would be around 27 wt% phosphoric acid.