Optical Properties of Novel Resin Matrix Ceramic Systems at Different Thicknesses

Translucency and colour masking ability of hybrid CAD/CAM materials with different thicknesses: in vitro study

OBJECTIVE

To evaluate effect of material thickness and translucency of two different hybrid CAD/CAM materials on their masking ability.

MATERIALS AND METHODS

40 rectangular-shaped specimens (12 × 14 mm) were obtained from Vita Enamic and Grandio blocks at 0.5 and 1 mm-thick (n = 10/group). Colour parameters of specimens were measured on PMMA tooth-coloured replica backgrounds (A2, C4) and black, white backings using dental spectrophotometer. Translucency parameter (TP) and masking ability (∆E00) values of tested materials with 0.5, and 1 mm thicknesses were calculated. Quantitative variables were compared between groups using student t-test.

RESULTS

TP and ∆E00 significantly decreased as thickness of tested materials increased. Grandio showed significantly higher TP values. There were significantly lower ΔE00 values for Vita Enamic compared to Grandio at 1 mm thickness and inversely insignificant at 0.5 mm. The 0.5 mm-thick ∆E00 of tested materials was above clinical acceptability threshold, whereas, 1 mm-thick did not exceed showing better masking properties.

CONCLUSIONS

Thickness is more effective for colour masking than translucency. In thin thickness, the masking ability is less effective, irrespective of tested materials. Translucency of tested materials was affected by their composition. Both hybrid CAD/CAM materials are promising alternatives for masking dark discolouration at 1 mm-thick.

Color Stability and Translucency of Polymer-Infiltrated Ceramic-Network Materials—A Systematic Review of the Literature

This systematic review aimed to compile information and report the color stability and translucency of polymer-infiltrated ceramic-network (PICN) materials for suitable clinical applications in dentistry. Original peer-reviewed articles in electronic databases including PubMed, MEDLINE, Scopus, and Web of Science were searched to identify relevant papers published between January 2013 and August 2020. The published papers were only in the English language and limited to in vitro studies, and experimental reports were considered. The data from nine studies were considered when reviewing the color stability and translucency of PICN in comparison to other commonly used restorative materials. Among the included studies, color stability assessment was performed in five studies, and the other four studies were involved in the combined assessment of both color stability and translucency. PICN materials are a comparatively newer class of restorative materials and are recommended to overcome the drawbacks of ceramics and resin composites. The outcomes of previous laboratory studies still do not provide convincing results regarding the optical properties of PICN materials. However, with existing sources and evidence, PICN materials exhibit less color stability than ceramics do but better color stability compared to that of resin nanoceramics (RNC) and resin composites. The translucency of PICN materials is low compared to that of ceramics, nanoceramics, and resin composites.