Helena Letícia Quirino Oliveira, DDS, MSc, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
Maria Tereza Hordones Ribeiro, DDS, MSc, PhD, Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.
Oper Dent. 2024 Mar 1;49(2):210-221. doi: 10.2341/22-112-L.
This study aimed to evaluate the optical and mechanical performance of two single-shade resin-based composites (RBCs) compared to those of a conventional RBC for restoring posterior teeth.
Two single-shade RBCs, Omnichroma (Tukoyama) and Vittra Unique APS (FGM), and a conventional RBC, Filtek Z350XT shade A2 (3M Oral Care), were evaluated in this study. The optical shade-matching performance was measured using a spectrophotometer. The light emitted by VALO Grand (Ultradent) and transmitted through the 2.0-mm RBC specimens was evaluated using beam profiling. Knoop hardness (KH, N/mm2), degree of conversion (DC, %) at the top and bottom, flexural strength (FS, MPa), elastic modulus (E, GPa), postgel shrinkage (Shr, %), and shrinkage stress (MPa) were evaluated. Scanning electron microscopy (SEM) was used to characterize the filler. Data for FS, E, and Shr were analyzed by one-way analysis of variance (ANOVA) and KH and DC by repeated one-way ANOVA measurement followed by Tukey test (α=0.05). The modified von Mises stress values, light transmission, and SEM images were analyzed qualitatively.
All single-shade RBCs exhibited higher chromatic adaptation than the Filtek Z350XT (p<0.001). Omnichroma exhibited less color difference than Vittra Unique APS, irrespective of the shade. The light transmitted through Omnichroma and Vittra Unique APS increased during polymerization. KH and DC values were significantly reduced from the top to the bottom of the specimens for all RBCs (p<0.001); however, the ratio values were always higher than 80%. In general, all RBCs demonstrated similar mechanical properties. All RBCs exhibited a similar FS (p=0.083) and Shr value (p=0.144). Filtek Z350XT exhibited significantly higher E (p<0.001) than both single-shade RBCs. All RBCs exhibited similar shrinkage stress during restoration and similar residual stress during occlusal loading.
Single-shade Omnichroma and Vittra Unique APS increased light transmission during light-activation, demonstrating better chromatic adaptation than conventional Filtek Z350XT. In general, Omnichroma and Vittra Unique APS exhibited similar mechanical properties and shrinkage stress distributions as Filtek Z350XT during light-activation and occlusal loading.
本研究旨在评估两种单色调树脂基复合材料（RBC）与传统 RBC 在后牙修复中的光学和机械性能。
本研究评估了两种单色调 RBC，即 Omnichroma（拓美）和 Vittra Unique APS（FGN），以及一种传统 RBC，Filtek Z350XT 色号 A2（3M 口腔护理）。使用分光光度计测量光学比色匹配性能。通过光束分析评估 VALO Grand（Ultradent）发出并通过 2.0-mm RBC 样本传输的光。评估了维氏硬度（KH，N/mm2）、顶部和底部的转化率（DC，%）、弯曲强度（FS，MPa）、弹性模量（E，GPa）、凝胶后收缩（Shr，%）和收缩应力（MPa）。使用扫描电子显微镜（SEM）来表征填料。FS、E 和 Shr 的数据采用单向方差分析（ANOVA）进行分析，KH 和 DC 采用重复单向方差测量，然后采用 Tukey 检验（α=0.05）。对改性 von Mises 应力值、透光率和 SEM 图像进行定性分析。
所有单色调 RBC 的比色适应能力均高于 Filtek Z350XT（p<0.001）。Omnichroma 表现出的色差比 Vittra Unique APS 小，与色调无关。Omnichroma 和 Vittra Unique APS 透过的光在聚合过程中增加。所有 RBC 样本的顶部和底部 KH 和 DC 值均显著降低（p<0.001）；然而，比值始终高于 80%。一般来说，所有 RBC 均表现出相似的机械性能。所有 RBC 的 FS（p=0.083）和 Shr 值（p=0.144）均相近。Filtek Z350XT 的 E 值显著高于两种单色调 RBC（p<0.001）。所有 RBC 在修复过程中表现出相似的收缩应力，在咬合加载时表现出相似的残余应力。
单色调 Omnichroma 和 Vittra Unique APS 在光激活过程中增加了光传输，表现出比传统 Filtek Z350XT 更好的比色适应能力。一般来说，在光激活和咬合加载过程中，Omnichroma 和 Vittra Unique APS 与 Filtek Z350XT 相比，表现出相似的机械性能和收缩应力分布。
Zotero 插件