Department of Conservative Dentistry and Periodontology, University Hospital, Ludwig-Maximilians-University, LMU Munich Goethestr. 70, 80336 Munich, Germany.
J Dent. 2022 Jan;116:103915. doi: 10.1016/j.jdent.2021.103915. Epub 2021 Dec 3.
The study aims to investigate the long-term mechanical characteristics, reliability, and light transmission of novel, one shade resin-based composites (RBC).
120 Specimens (n = 20) of three RBCs (Venus Diamond/VD, Venus Pearl/VP, Omnichroma/OC) were used in a three-point bending test, to determine flexural modulus (E) and flexural strength (σ). Testing ensued after 24 h or thermocycling (TC/10,000 cycles, 5/55 °C). Each fracture mechanism and filler system were documented, using light and scanning electron microscopy. A depth-sensing indentation test (n = 6) quantified the indentation modulus (Y), Martens/Vickers hardness (HM, HV) and creep (Cr). Incident (I) and transmitted irradiance (I) plus radiant exposure (RE) per RBC were measured employing a USB4000 spectrometer (n = 3) to calculate spectral absorbance. Data was tested for significant differences (α = 0.05) utilizing Student's t-tests, one- and multiple-way analysis of variance (ANOVA) and Tukey's post-hoc tests along with Pearson's correlational and Weibull analysis.
Initially, σ, E and Weibull modulus m were the highest for VP. After TC σ was comparable for VP and VD, E was higher for VD and m higher for VP. Maximum Y, HM, HV and Cr were always measured for VD. Inferior parameters, except Cr, were always recorded for OC. I, RE and absorbance differed marginally, with OC on top.
The variation in long-term mechanical stability and light transmission is significantly dependent on RBC formulation, most notably due to filler system and resin matrix.
One shade RBCs vary substantially in their material composition and characteristics, facilitating the diversity present in RBC direct restoratives.
本研究旨在探讨新型单色调树脂基复合材料（RBC）的长期力学特性、可靠性和透光率。
使用三点弯曲试验对三种 RBC（维纳斯钻石/VD、维纳斯珍珠/VP、全彩/OC）的 120 个样本（n=20）进行测试，以确定弯曲模量（E）和弯曲强度（σ）。在 24 小时后或热循环（TC/10,000 次循环，5/55°C）后进行测试。使用光镜和扫描电子显微镜记录每种断裂机制和填料系统。深度感应压痕试验（n=6）用于量化压痕模量（Y）、马氏体/维氏硬度（HM、HV）和蠕变（Cr）。采用 USB4000 分光光度计（n=3）测量每个 RBC 的入射（I）和透射辐照度（I）加辐射暴露（RE），以计算光谱吸收率。利用学生 t 检验、单因素和多因素方差分析（ANOVA）以及 Tukey 事后检验以及 Pearson 相关和威布尔分析对数据进行显著性差异检验（α=0.05）。
最初，VP 的 σ、E 和威布尔模数 m 最高。经过 TC 后，VP 和 VD 的 σ 相当，VD 的 E 更高，VP 的 m 更高。VD 的 Y、HM、HV 和 Cr 始终最大。OC 的参数除 Cr 外均较差。OC 的 I、RE 和吸收率略有差异，位居榜首。
长期机械稳定性和透光率的变化明显取决于 RBC 的配方，最显著的是由于填料系统和树脂基质。
单色调 RBC 在其材料组成和特性方面存在很大差异，这使得 RBC 直接修复体具有多样性。
