Effect of intracanal restorative material on the stiffness of endodontically treated teeth

This study compared the ability of various intracanal restorative materials to restore the stiffness of endodontically treated teeth. We randomly placed bovine central incisors into six groups. We did not instrument negative control teeth, and we instrumented, but did not restore, positive control teeth. We restored teeth in the experimental groups with resin-based composite, resin-based composite plus a fiberglass post, or resin-based composite plus a cemented metal post. We subjected all teeth to nondestructive, compressive testing and recorded the stiffness of each sample. Results indicated that performing endodontic access and instrumentation alone resulted in a 24% loss in tooth stiffness. Teeth restored using an intracanal resin bonding technique alone or in combination with a post regained the stiffness lost from access and instrumentation, and teeth that were restored with bonded resin and a metal post cemented with Panavia 21 cement were significantly stiffer than the untreated negative control group (p < 0.05). Our results suggest that intracanal resin bonding techniques may reduce the need for immediate crown placement after endodontic therapy.