Xenogenous Block Graft Cracked: What Should I Do?

You have a problem my friend, after such a long time you shouldnt be able to see the block. greft should be pretty much solid bone now. I would need to know more about the patient to give some advise on what to do. Hiperbaric O2 is a very effective treatment aid in big grafts. Is there any movement in the block or heavy compression, is he/she a smoker?, is there indication of osteoporosis and if so is the patient taking allendronic acid or similar? Diabetes or crticoid use? any heavy anti hippertensive meds?Anti cloughting meds? let us know so we can give a most educated advise. best of luck

This is a problem with xenografts and xenograft blocks and allograft solid blocks. First they have unpredictable resorption, and fail to fully integrate. Autogenous cortical blocks incorporate more predictably. However, even their outcortical strut can sometimes be white and lack vascularity when prepping for implants. That being said, nothing works better for onlays than autogenous tissue. Allograft blocks and certainly xenograft blocks should IMHO be reserved for patients who cannot have autogenous harvest for some reason. Then it should be stated clearly, the probability of integration is as predictable as autogenous bone and resorption rates are higher.

you'll have to understand the basis of putting the graft... and that is you want bone to replace it after say 4-6 months of healing, if you could still see the graft, you should ideally wait for some more time or think of some more underlying causes, now since you've done the case you just have one option... and that is to wait and hope for the best.

Xenografts, from what I know, are more mineralized than autogenous bone and thus remodel quite slowly compared to autogenous bone. Autogenous bone grafts can remodel/resorb to a considerable degree (perhaps 30%) and quite quickly (within 4 months). So, I wouldn't be surprised if, 6 months later, a xeno block seemed morphologically unchanged. Additionally, autogenous block grafts can and do crack when implants are placed. There are a variety of ways to deal with this, including placing screws and also particulate grafting, using a membrane, as you did. Usually, if the implant is sufficiently anchored in native bone, if the block bleeds normally with osteotomy preparation and healing is uncomplicated, the result will be good.

The Xenograft materials are of a large particle size and are sintered at high heat. The sintering makes this acy like a ceramic. Ceramics are hard, brittle and do not resorb well. Due to the large particle size and slow resorption it is hard on the RES/immune system and you get incomplete resorption. To get a better understanding, I suggest you and others read "Bone Graft Substitutes" edited by Cato T. Laurencin, MD, PhD. This book gives on a good overview of the materials, without the commercial input. I have found "Osteogen" to be an excellent particulate synthetic bone graft material, that actually works in a predictable manner.