Paravina Rade D, Westland Stephen, Kimura Mikio, Powers John M, Imai Francisco H
Department of Restorative Dentistry and Biomaterials, University of Texas Dental Branch at Houston, TX 77030-3402, USA.
Dent Mater. 2006 Oct;22(10):903-8. doi: 10.1016/j.dental.2005.11.018. Epub 2005 Dec 27.
To evaluate the in vitro blending effect (BE) of layered resin composites related to material, shade, and differences in color and translucency between compared materials.
Specimens made of two composites (2CS, n=5) consisted of the outer composite with an outer diameter of 10mm, 4mm thick and an inner diameter of 4mm, 2mm thick for the inner composite. Thus, the inner composite was encircled by a 3mm outer composite around its circumference and backed by a 2mm thick outer composite, to simulate a dental restoration surrounded by hard dental tissues. The outer composite was Palfique Estelite (PE, C2 shade, standard shade), while the inner composites were PE A2, B2 and C2 shades and corresponding shades of Point 4 (P4), Tetric Ceram (TC) and Filtek A110 (FA) composites (batch shades). Single-composite, disk-shaped specimens (1CS) of all five shades (D=10mm, 2mm thick, n=5) were made as well. Visual color assessments were done by six observers using a lightbooth and 1 (mismatch) to 5 (perfect match) scale. The BE was calculated as a difference in scores between corresponding 2CS and 1CS. Z-scores and corresponding BE values (BE(Z)) were calculated. 1CS were also evaluated using a spectrophotometer.
Blending effect ranged from -0.4 to 2.2, while BE(Z) ranged from -0.6 to 3.0. Mean visual scores for 1CS and 2CS were 1.8 (1.2) and 2.2 (1.3), respectively. BE increased with a decrease in color difference (r=0.41) and increase of translucency parameter (TP, r=0.77). High agreement was recorded among pairs of observers for both 1CS, r=0.95 (0.03) and 2CS, r=0.96 (0.02).
Blending effect is composite and shade dependent. Quantifying of blending potential of dental materials might provide useful clinical information for dental professionals.
评估分层树脂复合材料的体外融合效果（BE），该效果与材料、色度以及所比较材料之间的颜色和透明度差异有关。
由两种复合材料制成的标本（2CS，n = 5），外层复合材料外径为10mm，厚4mm，内层复合材料内径为4mm，厚2mm。因此，内层复合材料在其圆周周围被3mm厚的外层复合材料包围，并由2mm厚的外层复合材料支撑，以模拟被坚硬牙体组织包围的牙齿修复体。外层复合材料为Palfique Estelite（PE，C2色度，标准色度），而内层复合材料为PE A2、B2和C2色度以及Point 4（P4）、Tetric Ceram（TC）和Filtek A110（FA）复合材料的相应色度（批次色度）。还制作了所有五种色度的单复合材料圆盘形标本（1CS，直径D = 10mm，厚2mm，n = 5）。由六名观察者使用灯箱并以1（不匹配）至5（完美匹配）的量表进行视觉颜色评估。融合效果计算为相应的2CS和1CS之间的分数差异。计算Z分数和相应的融合效果值（BE(Z)）。还使用分光光度计对1CS进行评估。
融合效果范围为-0.4至2.2，而BE(Z)范围为-0.6至3.0。1CS和2CS的平均视觉评分为分别为1.8（1.2）和2.2（1.3）。融合效果随着色差的减小（r = 0.41）和透明度参数（TP，r = 0.77）的增加而增加。对于1CS（r = 0.95（0.03））和2CS（r = 0.96（0.02）），观察者之间的一致性都很高。
融合效果取决于复合材料和色度。量化牙科材料的融合潜力可能为牙科专业人员提供有用的临床信息。
