Study says there is no problem performing immediate placement of implants in sites with periapical infection
Even if you don't place implants, it is good to be able to educate your patients on what to expect when referring them to an oral surgeon. It is often that we see cases of a failed root canal in a non-restorable tooth. Up at the apex, there is a periapical radiolucency indicating the presence of infection or at best, chronic inflammation. If it is a single rooted tooth, the patient is often better served by removing the tooth and placing the implant the same day, allowing for a single phase of healing. But what about that lesion at the root tip? Can you still put the implant in without worry of failure?
Dr. Paul Fugazzotto published a retrospective study in the International Journal of Oral Maxillofacial Implants that looked to answer this question. Looking at 418 different sites over a 14 year period, he found that implant survival rates in cases with periodical pathology matched those placed in bone with no infection. Overall, he saw a 97.8% success rate. I don't think we could necessarily claim that for the average root canal.
See the abstract at PubMed.