PhD student, Department of Operative Dentistry, Endodontic and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.
Post-Doctoral Researcher, Department of Operative Dentistry, Endodontic and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.
J Prosthet Dent. 2020 Nov;124(5):614.e1-614.e5. doi: 10.1016/j.prosdent.2020.03.029. Epub 2020 Jul 4.
Information related to the optical and surface properties, including health compatibility, surface roughness, and esthetics, of 3D-printed dental materials is scarce.
The purpose of this in vitro study was to compare the physical and surface properties of a 3D-printed resin with those of materials used for interim restorations.
A 3D-printed resin (PR) (NextDent C&B MFH; 3D Systems), an autopolymerizing interim material (BA) (Protemp 4; 3M ESPE), and a composite resin (Z350) (Filtek Z350XT; 3M ESPE) were tested for degree of color change (ΔE) (n=7) at different timepoints-24 hours after polishing/baseline (P0), 8 days after polishing (P1), and after artificial aging in water at 60 °C for 24 hours (P2)-by using a CIELab-based colorimeter; flexural strength (σ) (n=10) with a 3-point bend test; Knoop hardness (H) (n=8); and surface roughness (Ra) (n=7) with a profilometer. All specimens were polished 24 hours after polymerization, except for the additional group for surface roughness (BA) without polishing (BANP). A statistical analysis was performed by using 2-way repeated-measures ANOVA followed by the Fischer test for ΔE and 1-way ANOVA followed by the Fisher test for microhardness and surface roughness (α=.05).
The Z350 showed the highest values for σ and H, followed by PR. BA showed the lowest results for both tests (P<.05). Considering roughness, the Z350 showed similar values to those of BA but lower than PR; PR showed similar roughness when compared with BA. PR showed the highest color variation among the groups at all timepoints, followed by BA. The Z350 was the most color stable material at all timepoints.
The 3D-printed composite resin had adequate mechanical and surface properties for an interim restorative material. It has the potential to be a low-cost workflow in dentistry, although its color stability could be a concern for long-term use.
关于 3D 打印牙科材料的光学和表面特性，包括健康兼容性、表面粗糙度和美观度，相关信息很少。
本体外研究的目的是比较 3D 打印树脂与用于临时修复的材料的物理和表面特性。
测试了一种 3D 打印树脂（PR）（NextDent C&B MFH；3D Systems）、一种自聚物临时材料（BA）（Protemp 4；3M ESPE）和一种复合树脂（Z350）（Filtek Z350XT；3M ESPE）在不同时间点的颜色变化程度（ΔE）（n=7），分别为抛光/基线后 24 小时（P0）、抛光后 8 天（P1）和在 60°C 水中人工老化 24 小时后（P2），使用基于 CIELab 的比色计；弯曲强度（σ）（n=10），三点弯曲试验；维氏硬度（H）（n=8）；和表面粗糙度（Ra）（n=7），采用轮廓仪。除了用于表面粗糙度（BA）的额外无抛光组（BANP）外，所有样本均在聚合后 24 小时进行抛光。采用 2 因素重复测量方差分析，随后对 ΔE 进行 Fischer 检验，对微观硬度和表面粗糙度采用单因素方差分析，随后进行 Fisher 检验（α=.05）。
Z350 显示出最高的 σ 和 H 值，其次是 PR。BA 在这两项测试中的结果均最低（P<.05）。考虑到粗糙度，Z350 与 BA 的值相似，但低于 PR；PR 与 BA 的粗糙度相似。PR 在所有时间点的颜色变化最大，其次是 BA。Z350 是所有时间点最稳定的颜色材料。
3D 打印复合树脂具有作为临时修复材料的足够的机械和表面性能。它有可能成为牙科领域的低成本工作流程，尽管其颜色稳定性可能是长期使用的一个问题。
