Medication related osteonecrosis of the jaws (MRONJ) is a disorder with bone maturation that occurs as a result of taking certain medications (historically bisphosphonate drugs such as Fosamax; more recently with antiangiogenic drugs such as Denosumab; and mainly from injectable forms of these drugs used in chemotherapy such as Zometa) where dental related disease processes or dental procedures result in a dead-bone disease (osteonecrosis of the jaws). This disease process typically just affects the tooth bearing areas of the jaws, although I have seen cases involving the palate, sinuses, and nasal structures as well.

Simply put, these drugs cause a blockage of the natural re-uptake of bone in what would be the normal bone apposition and re-uptake process that our skeletons go through. The result is to get a net increase in bone mass. The technical problem is that the resultant bone is a buildup of “old bone” which may be more prone to healing problems.

The prescribers of these medications, especially the oncologists, are doing a much better job of dosing these than even 10 years ago. We saw the biggest problem in the first years of this century when less was known and greater doses were given. Fortunately it has become a rarer problem.

The oral surgery association here in America has put out a “white paper” on MRONJ which was last updated in 2014 suggesting that the disorder has not changed much in the past 5 years. I have put the link below and I recommend looking at this if you have an interest. I follow their guidelines in general when faced with these cases. Because these are now more-rare cases I might suggest referral to regional medical centers with oral surgery services such as oral surgery residency programs if that is available. This facilitates best-care practices and usually helps to add to the knowledge base in the study of these problems. Again, fortunately, improvement in the dosing regimens has reduced the number of cases we are seeing.