Hip Graft: How Long to Wait Before Placement of Implants in Maxilla?

2 months otherwise it'll start to resorb

For an onlay autograft you need to wait 6 months for complete healing. The danger at this time(2 months) is that you could very easily pop you graft right off when you drill your osteotomy. Big block grafts take much longer to turnover than a particulate graft in a socket. You will also expect to lose 20-30% of the original bone volume no matter what. Don't worry, wait the appropriate time. Ask the surgeon who placed the graft- I am assuming you did not harvest and place it, otherwise you would have already known the answers to your questions.

Personally, I would have whoever did the hip graft place the implants. Otherwise, if it fails - whose fault is it?...the guy who grafted the bone or the guy who placed the implant?

I have already bone graft from hip before 11 years ago for dental implants. the bone faded away and the implants failed. moreover, I still have pain in the hip since then. DOctors advised that best bone for implants are the jaw bone not the hip bone. I was adivsed to wait 3 months only before implants placement. Last time I waitied 6 months after hip bone graft and I lost a lot of bone.

Charles, Good answer.

Bone grafts from the hip for augmentation vary widely in results for several reasons. When travecular bone is used as the graft, resorption of 50% or more can be observed during the first 6 months. Therefore a barrier membrane should be used maintain the space. Cortical grafts from a femur resorb much less and volume reductions of 10% to 20% are common, although one quarter of the time less than 10% is observed. The harvested bone takes more than 1 year to become mature bone. Re-entry at 2 months is too early- it alters the blood supply are a critical time to the graft, the implant surgery does not stop the resorption (it will continue and the implant may become compromised) and a cortical graft may become destroyed during implant insertion.

Re-entry at 6 months is optimal, although experienced clinicians may be able to use a 4 month time frame. At 6 months most of the resorption is complete, so you can evaluate if additional augmentation is needed before or during the implant insertation is required and although the graft is not all mature bone, enough bone has turned over to insure the process will continue. The implants are usually allowed to integrate for 6 months which means its host bone is in place 1 year prior to loading. Since regrafting is possible at implant insertion, an experienced surgeon familiar with augmenting procedures is suggested for implant insertion. If not, a CT and longer time frames are beneficial.

The re-entry depends on the way of placement of the graft. We use now since more than 10 years mono-cortical stripes to create the outer contour and fill the spaces with compressed spongy bone. There is no need for any membrane or additonal grafting material. We do the implant placement at the time of screw removal two month after grafting and see also only a smal resorption of maximum 10 % of vertical height.

For over 10 years we performed autogenous iliac crest composite bone grafts with simultaneous Brånemark implant placement securing the graft. We had virtually no loss of implants or bone, except in one patient who was an addicted heavy smoker. We performed major grafting on about 30 patients. But, since the introduction of Zygoma implants in the U.S. in '97, which are highly predictable and both easier and faster for patients, we haven't done any iliac crest bone harvesting for resorption indications for over a decade. In that last 12 years, we've continued to follow our iliac bone-grafted patients and not one has lost their prosthesis or any implants.

I agree with Dr. Misch. Two months is too soon. The graft has not adequately remodeled and fused to the host bone. It is unlikely the graft would “pop off” in experienced hands. It just is still remodeling and needs more time. Four months is usually adequate especially for width augmentation cases (vs. vertical bone augmentation where six months may be preferred). You will notice bone resorption – all onlay bone grafts resorb to some degree. Resorption is a necessary and inherent aspect of graft incorporation. Cortical and corticocancellous bone grafts resorb less than cancellous bone grafts used for onlay grafting. The amount of autograft resorption can vary but usually is less than 30%. The surgeon will typically overbuild the site to account for some volume loss. Barrier membranes are not routinely needed for block grafts. Although the graft will remodel over the year the greatest volume change is in the first three months (according to CT scan studies by Nystrom). If you are worried about the bone volume for implant placement I recommend you have the surgeon that did the graft place the implants. The fact that you are asking how long to wait to place the implants leads me to believe you do not have a great deal of experience placing implants in grafted bone. It can be much different than native bone (especially hip bone grafts). This may be the best approach for your patient. Your patient has endured some discomfort, significant cost and time to get to this point. They deserve the best chance at a successful outcome and you will appreciate favorable implant placement (if you are restoring the case). The implant healing time will depend on the bone density but six months is a good reference point. With microtextured implant surfaces used today a four month healing period may be adequate for second stage surgery. Allowing the soft tissues to heal for an additional two months will meet the six month time frame Dr. Misch proposed. Good Luck

How many of you after hip bone graft and implant placement give walking stick free as a package or bill that at a discount.

Dr. Baliga, Your comment is welcomed as there are many misconceptions regarding the iliac bone graft donor site. Patients may require the use of crutches or a walker up to one week after surgery. This is due to the reflection of the muscles from the iliac crest and postoperative discomfort. However, with the use of a local anesthesia pain pump via a catheter (bupivicane pain pump) most patients have only mild to moderate pain well controlled with analgesics. The literature on iliac bone grafts shows minimal complications associated with gait but many dentists think this procedure affects their patient’s long term ability to return to normal activity. This is simply not the case and the current literature reflects this. Maybe things are different in India but in the US this procedure is performed as an outpatient surgery and patients go home the same day. The incidence of serious complications is very low and studies reveal most patients would repeat the surgery again. 1. Falkensammer et al Modified iliac bone harvesting--morbidity and patients' experience. J Oral Maxillofac Surg. 2009 Aug;67:1700-5 2. Kalk WW, Raghoebar GM, Jansma J, Boering G. Morbidity from iliac crest bone harvesting. J Oral Maxillofac Surg 1996;54:1424-9.) In fact the Kalk et al group found chin graft patients had more pain (rated by the patients) than iliac bone graft patients. The iliac crest donor site is reserved for cases requiring larger amounts of autogenous bone for ridge augmentation. The benefits far outweigh the risks of experienced surgeons harvesting bone from this donor site. I appreciate your comment but find it is indicative of the misinformation and lack of knowledge regarding this procedure. Until we have predictable alternatives to autogenous bone this procedure will continue to be invaluable in maxillofacial reconstruction.

Thank you very much for the comments, especially from Dr Misch & Dr C. Actually, an orthopaedic surgeon harvested the cortico-cancellous hip graft and I grafted it onto the labial/buccal of the maxillary ridge from 15(#4) to 23(#11) area. There is no vertical deficiency. The horizontal defect is down to 1mm width(from CT scan)of just cortical plate without any cancellous content,in the canine/incisors area.The main cortico-cancellous blocks were screwed down, the spaces were filled with crushed cancellous chips. Lyostypt bovine membrane was used to help stabilise the chips. Now, at two and a half months, the areas of the cancellous chips are resorbing rapidly whereas, tha cortical areas seems stable.What do you think of re-entry at 4 months, leaving the screws intact during drilling for implant placement, and not even removing them if they do not interfere with the implant position? I also plan to graft with BioOss any residual defects at implant placement. At the initial surgery I actually grossly overgrafted, and patient was complaining that she looked like a gorilla. She wanted so much for it to resorb down. So, there is no way I could have increased augmentation at that point in time. It was with great difficulty that I managed to obtain primary closure, but I did, and soft tissue healing is great. With the chin grafts, I've not noticed much resorption, even at re-entry at 6 months. Maybe, we normally don't take big chunks of chin, that's why less resorption?

Re-entry at four months sounds good in this case. As mentioned you can leave the fixation screws in during implant placement but I would remove them thereafter. If the screws are remote from the ridge crest access for implant placement you can make a small incision in the buccal mucosa over the screw head for retrieval. This will help maintain blood supply to the bone graft. You can perform additional grafting around the implants if needed using GBR techniques (bone substitute + collagen barrier membrane). It sounds like you overbulked the graft appropriately and were able to manage the flap closure. Graft resorption is not related to the gross size of the block. It is related to the microarchitecture. There is less resorption with chin bone grafts as they are dense cortical bone (D1, D2). Iliac bone grafts often have a thinner cortical layer and a larger cancellous portion (corticocancellous). As they are less dense (D2, D3) they typically exhibit more volume change upon incorporation. We can reduce graft resorption with hip bone grafts by using the thicker cortex from the iliac crest as the reconstructed ridge crest (L or J shaped graft over the residual ridge). Good Luck.

quatre mois, sans doute.

Monsieur Le Dr Jafri ecrire en Anglais sil vous plait. Merci

O.K.sir, the meaning is :four months and no doubt about it.

Hi, A hip graft to repair shin bone. Will the graft site ever heal to its original condition? Any complications in future?