Extracting in a patient on antiresorptives

The risk of osteonecrosis of the jaw after an extraction in a patient on an antiresorptive is set mostly by how much of the drug the patient has received, and the gap between the two populations is large: an international consensus put the incidence at 1% to 15% in oncology patients and 0.001% to 0.01% in osteoporosis, and a survey-and-examination study of patients on oral bisphosphonates found 0.10%, so the figure that gets quoted depends heavily on the denominator and the method behind it. In cancer patients the risk rose with the number of infusions and the duration of treatment in cohort studies, and in three pooled phase III trials it was 1.3% with zoledronic acid and 1.8% with denosumab, a difference that was not significant there, although a later meta-analysis of 23 trials did find a higher incidence with denosumab. Denosumab differs from the bisphosphonates in that its effect wears off rather than residing in bone, and stopping it produces a rebound in bone turnover with multiple vertebral fractures in some patients, which makes an unplanned pause a medical decision rather than a dental one. Short drug holidays before extraction have not been shown to reduce the risk in the retrospective cohorts and meta-analyses that have tested them, in oncology and osteoporosis patients, though one large-animal study found a benefit, and serum CTX has performed poorly as a predictor in three systematic reviews. My own position is that the risk follows cumulative dose — duration times the amount given — rather than the timing within an infusion cycle; I refer patients above my comfort level so that post-operative complications are managed by someone equipped for them, I do not use CTX, and I usually give antibiotics after the extraction, though there is a fair argument for starting them before.