Periapical microsurgery: an in vivo evaluation of endodontic root-end filling materials

The purpose of this study was to assess the healing of periapical tissues using three different materials (IRM [L.D. Caulk Inc, Dentsply International Inc, Milford, DE], Geristore [Den-Mat, Santa Maria, CA], and MTA [ProRoot MTA; Dentsply Tulsa Dental Specialties, Tulsa, OK]) after endodontic microsurgery in an animal model. Using beagle dogs as a study model, 48 bicuspids were accessed, instrumented, and intentionally infected. The surgical procedures were performed after 30 days following the radiographic confirmation of periapical radiolucencies. The root canals were still infected and had no disinfection procedure carried out. The root ends were resected, retrograde preparations were completed, and the experimental materials were placed under surgical operating microscopy. After a period of 6 months, digital radiographic images of the periradicular areas were taken. The samples were prepared for histologic evaluation. Although Geristore showed no radiographic difference when compared with the other groups, it showed the least favorable healing in the histologic evaluation. Our histologic and radiographic results showed no statistical difference between MTA and IRM.