Optical Properties of CAD/CAM Interpenetrating Phase Composites — An Overview

This review presents various interpenetrating phase composite (IPC) materials currently used in computer-aided design/computer-aided manufacturing (CAD/CAM) systems and to evaluates how the optical properties of those materials are affected by various factors. In the field of dentistry, selecting materials compatible with dental tissues is key to clinical success of restorative materials. Understanding the optical properties of a restorative material aids in material selection and provides insights into the material’s clinical performance and esthetic longevity. Such knowledge can in turn help clinicians select the best treatment option for their patients. Interpenetrating phase composite materials combine the optical and mechanical properties of ceramics and composite resins; they are often used in direct/indirect restorative options such as inlays, onlays, veneers, single crowns, implant-supported crowns, and short-span fixed partial dentures with esthetically favorable outcomes. The color of a material, which plays an essential role in the esthetic outcome, can change over time depending on different intrinsic and extrinsic factors. Those intrinsic factors include chemical composition, resin-matrix structure, and filler particle sizes; extrinsic factors include surface treatment protocols, the patient’s smoking status, and the consumption of beverages such as coffee, tea, red wine, fruit juice, cola, etc. To fabricate restorations that complement a person’s natural teeth, it is essential to determine the color properties of these materials (e.g., translucence, hue, chroma, and opalescence).