Advanced Prosthodontics, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90089, USA.
J Prosthet Dent. 2011 Mar;105(3):185-93. doi: 10.1016/S0022-3913(11)60027-9.
N-vinylcaprolactam (NVC)-containing glass ionomers are promising dental restorative materials with improved mechanical properties; however, little information is available on other physical characteristics of these types of modified glass ionomers, especially their surface properties. Understanding the surface characteristics and behavior of glass ionomers is important for understanding their clinical behavior and predictability as dental restorative materials.
The purpose of this study was to investigate the effect of NVC-containing terpolymers on the surface properties and bond strength to dentin of GIC (glass-ionomer cement), and to evaluate the effect of NVC-containing terpolymer as a dentin conditioner.
The terpolymer of acrylic acid (AA)-itaconic acid (IA)-N-vinylcaprolactam (NVC) with a molar ratio of 8:1:1 (AA:IA:NVC) was synthesized by free radical polymerization and characterized using nuclear magnetic resonance ((1)H-NMR) and Fourier transform infrared spectroscopy (FTIR). The synthesized terpolymer was used in glass-ionomer cement formulations (Fuji IX GP). Ten disc-shaped specimens (12 × 1 mm) were mixed and fabricated at room temperature. Surface properties (wettability) of modified cements were studied by contact angle measurements as a function of time. Work of adhesion values of different surfaces were also determined. The effect of NVC-modified polyacid on the bond strength of glass-ionomer cement to dentin was investigated. The mean data obtained from contact angle and bonding strength measurements were subjected to t test and 2-way ANOVA (α=.05).
NVC-modified glass-ionomer cements showed significantly (P<.05) lower contact angles (46 degrees) and higher work of adhesion (W(A)=60.33 erg/cm(2)) in comparison to commercially available Fuji IX GP (57 degrees and W(A)=53.01 erg/cm(2)). The wettability of dentin surfaces conditioned with NVC-containing terpolymer was significantly higher (P<.05) (22 degrees, WA=73.77 erg/cm(2)) than dentin conditioned with GC dentin conditioner (29 degrees, W(A)=70.52 erg/cm(2)). The experimental cement also showed significantly higher values for shear bond strength to dentin (8.7 ±0.15 MPa after 1 month) when compared to the control group (8.4 ±0.13 MPa after 1 month).
NVC-containing terpolymers may enhance the surface properties of GICs and increase their bond strength to the dentin. Furthermore, NVC-containing polyelectrolytes are better dentin conditioners than a commercially available dentin conditioner (GC dentin conditioner).
含 N-乙烯基己内酰胺（NVC）的玻璃离子体是一种有前途的牙科修复材料，具有改善的机械性能; 然而，关于这些类型的改性玻璃离子体的其他物理特性，特别是其表面特性的信息很少。了解玻璃离子体的表面特性和行为对于理解其作为牙科修复材料的临床行为和可预测性很重要。
本研究旨在研究含 NVC 的三元共聚物对玻璃离子体水泥（GIC）表面性能和对牙本质粘结强度的影响，并评估含 NVC 的三元共聚物作为牙本质调节剂的效果。
通过自由基聚合合成了摩尔比为 8:1:1（AA:IA:NVC）的丙烯酸（AA）-衣康酸（IA）-N-乙烯基己内酰胺（NVC）三元共聚物，并通过核磁共振（1H-NMR）和傅立叶变换红外光谱（FTIR）进行了表征。合成的三元共聚物用于玻璃离子体水泥配方（Fuji IX GP）。在室温下混合并制备了十个圆盘状试件（12×1mm）。通过接触角测量研究了改性水泥的表面性能（润湿性）随时间的变化。还确定了不同表面的粘附功值。研究了 NVC 改性聚酸对玻璃离子体水泥与牙本质粘结强度的影响。接触角和粘结强度测量得到的平均值数据进行 t 检验和 2 路方差分析（α=.05）。
与市售 Fuji IX GP（57 度和 W（A）=53.01 erg/cm2）相比，NVC 改性玻璃离子体水泥的接触角（46 度）和粘附功（W（A）=60.33 erg/cm2）明显降低（P<.05）。用含 NVC 的三元共聚物处理的牙本质表面的润湿性明显更高（P<.05）（22 度，WA=73.77 erg/cm2），而用 GC 牙本质调节剂处理的牙本质（29 度，WA=70.52 erg/cm2）。与对照组（1 个月后 8.4±0.13MPa）相比，实验水泥对牙本质的剪切粘结强度也明显更高（1 个月后 8.7±0.15MPa）。
含 NVC 的三元共聚物可增强 GIC 的表面性能并提高其与牙本质的粘结强度。此外，含 NVC 的聚电解质比市售牙本质调节剂（GC 牙本质调节剂）更适合作为牙本质调节剂。
