Related Experiment Video
Updated: May 27, 2026

Measuring the Mechanical Properties of Glass Fiber Reinforcement Polymer Composite Laminates Obtained by Different Fabrication Processes
Published on: June 30, 2023
Influences of composite-composite join on light transmission characteristics of layered resin composites
Kanako Horie1, Masatoshi Nakajima, Keiichi Hosaka
1Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan.
Objectives:
The purposes of this study were: (1) to determine the light transmission characteristics (straight-line and diffusion transmission) of bulk-filled and layered resin composites, and (2) to evaluate the effect of layering filling on translucency and color appearance of resin composites.
Methods:
Three light-cured resin composites (EsteliteΣ, Tokuyama Dental; Beautifil II, Shofu and Clearfil Majesty, Kuraray Medical) in A2 and OA2 shades were used in this study. 2 mm-thick resin composite discs were prepared by two methods; bulk filling technique (2 mm filling at one time), layering technique (two layers each 1 mm thickness). The transmitted light intensity of each resin composite disc was measured using a goniophotometer, and diffusion factor (DF), an indicator for diffuse transmission property, and peak gain (G0) for straight-line transmission were calculated from the light distribution graphs. Color was measured according to the CIELAB color scale on a spectrophotometer, and the translucency parameter (TP) and color difference (ΔE(*)) between bulk-filled and layered specimens were calculated. The data were statistically analyzed using three-way ANOVA, and Dunnett's T3 and t-test for post-hoc test.
Results:
Three-way ANOVA revealed that the layered specimens had significantly lower G0 values and higher DF values than the bulk-filled specimens, and significantly reduced TP values. The color differences (ΔE(*)) ranged from 1.07 to 1.85 between the bulk-filled and layered specimens.
Significance:
Resin composite placed in layers exhibited reduced straight-line light transmission and increased diffusion transmission compared with bulk-filled resin composite. The layering technique affected the translucency and color rendition of resin composite.
More Related Videos
06:26Experimental Implementation of a New Composite Fabrication Method: Exposing Bare Fibers on the Composite Surface by the Soft Layer Method
Published on: October 6, 2017
07:04Confocal Time Lapse Imaging as an Efficient Method for the Cytocompatibility Evaluation of Dental Composites
Published on: November 9, 2014
Related Concept Videos
Composite Masonry Walls
Composite Bodies
Composite bodies have widespread applications in mechanical engineering, from automobiles to aircraft to rockets. For example, an automobile wheel comprises...
Bending of Members Made of Several Materials
Hooke's Law determines stress in each material, stating that stress is proportional to strain but varies due to each material's...
Fiber Reinforced Concrete