Dimitriadi Maria, Petropoulou Aikaterini, Papathanasiou Ioannis, Zinelis Spiros, Eliades George
Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
Department of Prosthodontics, School of Dentistry, National and Kapodistrian University of Athens, 115 27 Athens, Greece.
Materials (Basel). 2025 Aug 8;18(16):3721. doi: 10.3390/ma18163721.
The aim of this study was to evaluate (a) the degree of conversion (DC%), (b) film thickness, and (c) the effect of film thickness on DC% in modern light-cured resin composite restoratives [Filtek Universal (F), Clearfil Majesty ES 2 Universal (M), Tetric EvoCeram (T) and Viscalor (V)] used for luting composite onlays before/after preheating. For (a), the luting composites placed at 150 μm film thickness under the onlays (4 mm thickness, 2.9% transmittance) were light-cured for 120 s (3 × 40 s top, buccal, lingual sites) before and after preheating (54 °C/5 min-F,M,T and 65 °C/30 s-V). The DC% was measured at central, middle and side locations along the median in-length axis by ATR-FTIR spectroscopy. Specimens polymerized without onlays (40 s, top) served as controls. For (b), film thickness was measured employing a modified ISO 4049 standard (37 °C plate temperature, 5 N load) before and after preheating, using a dual-cured resin luting agent as control. For (c), onlays were luted with preheated T at 150 and 350 μm film thickness and light-cured for 2 × (3 × 40) s and 3 × (3 × 40) s, employing directly irradiated specimens (60 s, 120 s) as controls. For (a), significant differences were found in F and T before and after preheating. Before preheating, significant differences were registered between F-T, F-M, F-V and V-T, whereas after they were registered between F-M, F-T and F-V. All these values were significantly lower than the controls. For (b), significantly lower film thickness was recorded after preheating (-16.1--33.3%, highest in V), with a ranking of F, M > V > T (before) and F, M > T, V (after). All values were significantly higher than the control. For (c), increased exposure improved DC% in the greater spacer group, with the controls providing superior values. It can be concluded that the use of modern highly filled composites as luting agents for low translucency onlays may result in suboptimal polymerization and film thickness, warranting caution.
本研究的目的是评估（a）转化率（DC%）、（b）薄膜厚度以及（c）在预热前后用于粘结复合高嵌体的现代光固化树脂复合材料修复体[Filtek Universal（F）、Clearfil Majesty ES 2 Universal（M）、Tetric EvoCeram（T）和Viscalor（V）]中薄膜厚度对DC%的影响。对于（a），在高嵌体（4mm厚，2.9%透光率）下方以150μm薄膜厚度放置的粘结复合材料，在预热（54°C/5分钟 - F、M、T和65°C/30秒 - V）前后进行120秒的光固化（顶部、颊侧、舌侧部位各3×40秒）。通过ATR - FTIR光谱法在沿长度中轴线的中央、中间和侧面位置测量DC%。未放置高嵌体进行聚合的试样（40秒，顶部）用作对照。对于（b），在预热前后采用改良的ISO 4049标准（平板温度37°C，负载5N）测量薄膜厚度，使用双固化树脂粘结剂作为对照。对于（c），使用预热后的T以150μm和350μm的薄膜厚度粘结高嵌体，并分别进行2×（3×40）秒和3×（3×40）秒的光固化，以直接照射的试样（60秒，120秒）作为对照。对于（a），发现F和T在预热前后存在显著差异。预热前，F - T、F - M、F - V和V - T之间存在显著差异，而预热后，F - M、F - T和F - V之间存在显著差异。所有这些值均显著低于对照。对于（b），预热后记录到薄膜厚度显著降低（-16.1% - -33.3%，V中降幅最大），排序为F、M > V > T（预热前）以及F、M > T、V（预热后）。所有值均显著高于对照。对于（c），在较大间隔组中增加照射时间可提高DC%，但对照提供的数值更优。可以得出结论，使用现代高填充复合材料作为低透明度高嵌体的粘结剂可能会导致聚合效果和薄膜厚度不理想，需谨慎使用。
