IMMEDIATE IMPLANTS PLACED INTO INFECTED SITES - A HISTOMORPHOMETRIC STUDY IN DOGS

To study the effect of chronically infected sites on the immediate pla cement of implants, periapical lesions were induced in the third and f ourth premolars of four dogs and the contralateral teeth were used as controls. Nine months after the induction of periapical lesions, exper imental and control teeth were extracted, and 28 IMZ implants were imm ediately placed. After a healing period of 12 weeks, the animals were sacrificed, the hemi-mandibles were removed, and specimens were prepar ed to be hard-sectioned and stained with toluidine blue. All areas hea led without inflammation or exudation and all implants were clinically immobile and were radiographically determined to be surrounded by nor mal-appearing bone. Histologically, there were no signs of infection, and the histomorphometric analyses revealed that 28.6% and 38.7% had o sseointegrated for the experimental and control implants, respectively . The difference was not statistically significant. It was concluded t hat chronically infected sites, such as those showing signs of periapi cal pathosis, may not be a contraindication for immediate implants, if certain clinical measures and preoperative and postoperative care are taken.