Osseous reaction to implanted ZOE retrograde filling materials in the tibia of rats

The osseous reaction of IRM and EBA cement were studied utilizing an intraosseous implant technique in rats. Samples of IRM, EBA cement, and amalgam were placed into polyethylene tubes and subsequently introduced surgically into rat tibias. Specimens of each were evaluated histologically after 7, 14, 21, 56, and 100 days. The IRM and amalgam samples demonstrated essentially complete healing at 56 days. The EBA cement samples displayed a slightly greater inflammatory response up to the 56-day interval; however, they also showed complete healing by 100 days. A favorable osseous reaction was seen with both of these zinc oxide-eugenol materials.