Optical Properties of an Experimental Highly Aesthetic Composite Restorative

Objective:  It is well known that natural enamel has opalescent properties.  Opalescence is particularly evident in the incisal edge of a tooth.  It is also well known that dentin is fluorescent.  The fluorescent property of the dentin manifests itself under 365nm incident radiation.  The objective of this study is to demonstrate that an experimental highly aesthetic composite has opalescent properties in translucent (incisal) shades and good fluorescent properties in shade offerings of higher opacities.

Methods:  Filtek Supreme Clear Translucent (FSCT), Grandio Inscisal (GI), Vit-L-Esscence Translucent Amber (VLE), and an Experimental Clear Translucent (EXPCT), were compared for opalescence.  Disks were fabricated from each material.  Opalescence was measured using a spectrophotometer measuring CIELAB color in transmission mode, then in reflection mode.  The opalescence, designated Ca*b*, was calculated as the difference in the red-green coordinate (delta a*) and the blue-yellow coordinate (delta b*) between the reflected and transmitted colors of a 1mm thick disk.  

Esthet-X A3 (EXA3), Tetric EvoCeram A2 (TECA2), Grandio A2 (GA2), Premise A2 (PA2), and an Experimental A2 (EXPA2) composite were compared for fluorescence.  Materials were qualitatively compared using a Macbeth SpectraLight viewing box under diffuse 365nm incident light.

Results:

Means (standard deviations) of Ca*b* are listed in the table below along with p-values as compared to EXPCT at a 95% confidence interval (CI).

A qualitative visual comparison was made of fluorescence.  EXPA2 was similar to TECA2, GA2, and PA2.  EXPA2 was slightly brighter than EXA3.

Conclusions:  The opalescence character of EXPCT was equal to FSCT, and was greater than GI and VE.  The fluorescent character of EXPA2 was similar to TECA2, GA2, and PA2.  EXPA2 was slightly brighter than EXA3.