目的:评估光固化搪瓷贴面的颜色变化,双重固化树脂着色剂,或加热的树脂复合材料,以及评估这些剂的显微硬度和径向拉伸强度。
方法:对于颜色分析,使用RelyXUltimate(RU)或RelyX贴面(RV)树脂基着色剂,将0.5毫米厚的白云母增强玻璃陶瓷贴面(IPSEmpressCAD)粘合到40个牛牙块(n=10)上,或梯度直接(GD)和PalfiqueLx5(P)加热树脂复合材料。luting之后,样品进行热循环(10,000次循环)。在热循环之前和之后进行颜色分析(L*,a*,b*,ΔEab,ΔE)。对于显微硬度(努普)和径向拉伸强度测试,制作样品(Ø6x2mm)(RU,RV,GD,和P)。将样品细分为八组(n=10),并通过不同的陶瓷片(厚度为0.5mm或1.5mm)进行光固化。在显微硬度计中对顶表面进行努普显微硬度,以及在万能试验机上的径向拉伸强度。数据提交统计分析,使用双向方差分析,Tukey,和Kruskal-Wallis检验(α=0.05)。
结果:对于一般的颜色变化,两种材料之间没有统计学上的显著差异(ΔEab,P=0.57;ΔE00,P=0.50)。lutingagent和热循环之间没有相互作用,对于L*(P=0.87),a*(P=0.97)和b*(P=0.95)值。热循环仅显著影响L*值(P=0.047),周期后增加。对于显微硬度,考虑到着色剂和陶瓷厚度,差异有统计学意义(P<0.001)。GD加热树脂复合材料的显微硬度值明显低于所有其他材料,在两个陶瓷厚度。厚度为1.5mm时,RU水泥的显微硬度值高于RV和P材料。抗张强度的径向强度受影响显著(P=0.01),但不按陶瓷厚度(P=0.55)。GD树脂复合材料的径向拉伸强度高于RU,但是这两种材料都不与RV和P不同。
结论:加热树脂复合材料,用作遮光剂,显示出与光固化和双重固化树脂水泥相似的颜色稳定性,但其显微硬度受陶瓷厚度的影响。
OBJECTIVE: To evaluate color change in ceramic veneers luted to enamel with light-cured, dual-cured resin luting agents, or heated resin composites, as well as to evaluate microhardness and diametral tensile strength of these luting agents.
METHODS: For color analysis, 0.5 mm-thick leucite-reinforced glass ceramic veneers (IPS Empress CAD) were cemented onto 40 bovine dental blocks (n= 10) using RelyX Ultimate (RU) or RelyX Veneer (RV) resin-based luting agents, or Gradia Direct (GD) and Palfique Lx5 (P) heated resin composites. After luting, the specimens were subjected to thermocycling (10,000 cycles). Color analysis was performed before and after thermocycling (L*, a*, b*, ΔEab, ΔE₀₀). For the microhardness (Knoop) and diametral tensile strength tests, specimens (Ø 6 x 2 mm) were made (RU, RV, GD, and P). The specimens were subdivided into eight groups (n=10) and light-cured through different ceramic sheets (thicknesses of 0.5 mm or 1.5 mm). Knoop microhardness was performed on the top surface in a microhardness tester, and diametral tensile strength on a universal testing machine. Data were submitted to statistical analysis, using two-way ANOVA, Tukey, and Kruskal-Wallis tests (α= 0.05).
RESULTS: For the general color alteration, there was no statistically significant difference between the luting materials (ΔEab, P= 0.57; ΔE₀₀, P= 0.50). There was no interaction between luting agent and thermocycling, for L* (P= 0.87), a* (P= 0.97) and b* (P= 0.95) values. Thermocycling significantly affected only the L* values (P= 0.047), which increased after the cycles. For microhardness, there was a statistically significant difference considering luting agents and ceramic thickness (P< 0.001). GD heated resin composite presented significantly lower microhardness values than all other materials, at both ceramic thicknesses. At a thickness of 1.5 mm, RU cement had higher microhardness values than RV and P materials. Diametral tensile strength was significantly influenced by luting agent (P= 0.01), but not by ceramic thickness (P= 0.55). Diametral tensile strength of GD resin composite was higher than that of the RU, but neither of these two materials differed from RV and P.
CONCLUSIONS: Heated resin composite, used as luting agents, showed similar color stability to light-cured and dual-cure resin cements, however its microhardness was affected by ceramic thickness.