Radiopacity of Dental Materials: An Overview

Context: This study aimed to provide an overview of the literature on the radiopacity of dental materials in order to emphasize its importance. Evidence Acquisition: English-language literature was investigated using manual and electronic searches for the terms "radiopacity," "dental material," "cement," "composite," "ceramic," "endodontic root canal sealer," "bone graft," and "acrylic resin" in the databases of Medline, google scholar, and Scopus up to April ۲۰۱۶. Seventy-nine selected publications, including review articles, original articles, and books, were evaluated. Results: The radiopacity of different dental materials may be lower or higher than that of the replaced tissue depending on the restorative material used. The research revealed that highly-radiopaque materials should not be used in dental restorations, except as bone graft and endodontic root canal filling materials. For most of the dental restorative materials, moderate radiopacity within the range of the replaced dental tissue is recommended. However, the lower radiopacity of polymer-based restorative or prosthetic dental materials is still a significant clinical problem. Conclusions: The author recommends using highly-radiopaque materials whenever possible for treatment of bone defects and root canals. For dental materials that replace clinical crowns, the radiopacity should be within the range of that of the replaced tooth structure (dentin or enamel). The radiopacity of dental cements should be much higher than that of the enamel in order to facilitate detection of the thin cement remnants.