Decrease in Radiodensity at Graft Site: Doomed to Failure?

Dear Dr N OPG is not a very good diagnostic tool for measuring radioopacity.In case you want to see the grafted material try to do a periapical or a CT which will give you immediately the answer you are looking for.What kind of grafting material have you used?This could be the answer for the changes in radioopacity.Was it a resorbable material? I suggest doing a CT before Implant placement.

Dear Dr N, I think what you seeing there 3 weeks post op is the normal biology of bone graft resorption by the host tissue (which normally starts with increased osteoclastic activity 14 days after bone graft placement). If you wait 2-3 months you will see increasing radio-opacity with time which corresponds to bone substitution by host osteoblast and subsequent bony maturation. Even a Panoramic radiograph will pick the above sequence up and you will not need a CT scan or other fancy diagnostic modalities. This is normal biology of bone healing.

I' m pretty astonished by Dr. N's question: you have performed a lateral sinus lift and don't you even know the normal biology of a bone graft? Oh my God!

What was the material used?

The material used was pure phase beta tri calcium phosphate mixed with natural crystal hydroxyapatite and collgen fibres.

With respect for Don Callan question, i don't think that graft material should be the focusing problem; i mean that nowadys there is a consensus about the use of bone substitutes in sinus lift procedures. We have seen how bovine HA(ie. papers by Froum, Testori, Wallace) or pure beta phase TCP or any other material can promote osteoconduction and that there' s no statistically significative difference with respect to those sinuses grafted with autologus bone in hystomorfometry at 6 and 12 months. This is of a paramount importance because we can avoid grafting procedures from intra or extra oral sites and for this reason we can also reduce morbidity of our sinus lift procedures.

TCP or tricalcium phosphate is originally one of the osteoconductive materials which are fairly utilized in implant surgery to provide a scaffold or framework onto which new bone can grow. These materials act passively; providing no intrinsic bone growth function, which must be provided by the adjacent decorticated bony surface. These kinds of materials are more commonly utilized as a bone graft extenders. Bone graft extenders by definition allow a given amount of autogenous bone graft to be used across a greater surface area. These are combined with osteoinductive materials such as autograft or BMP which provide the osteogenic cells or biologic factors that impart the ability to differentiate primitive mesenchymal cells into osteoblasts. The most commonly used osteoconductive material is an allograft. Extensive clinical experience using allograft combined with autograft has demonstrated its efficacy in achieving newly formed bone. Therefore, allograft should only be used as a graft extender unless there is no other available autograft source or other osteoinductive material. Tricalcium phosphate, hydroxyapatite, and calcium sulfate are ceramics that have been widely used as osteoconductive materials. These materials are approved by the US Food and Drugs Administration (FDA) as bone fillers. Hydroxyapatite, the key mineral component of bone, is an essential element in the ossification pathway leading to new bone formation. Although it may take years to resorb following implantation, hydroxyapatite is biocompatible and exhibits the proper porosity to allow for osteoblastic ingrowth to achieve effective bony healing. Tricalcium phosphate (TCP) is another bone graft material that is biocompatible with the advantage of rapid resorption. This characteristic allows for a more accurate radiographic evaluation of the bony mass. Calcium sulfate is another commercially available bone graft material that has been successfully used as bone void filler. As with other ceramics, calcium sulfate is osteoconductive, providing scaffolding for new bone ingrowth. It has no osteoinductive properties, with a resorption rate of 4–6 weeks, making it an ideal carrier for antibiotics in bone infections. It is this short resorption time that makes calcium sulfate less than ideal material for bone formation attempts in oral and maxillofacial surgery. Osteoinductive scaffolding needs to be present for at least 6 months to allow for sufficient bony ingrowth and it is currently recommended only as a bone graft extender and not a bone graft substitute. By combining different ceramics which have unique proprietary formulations, bone graft materials with different rates of resorption, different pore sizes and handling characteristics can be engineered to improve handling characteristics, bioreabsorption rates, and osteoinductive agent binding efficacy.

For what it is worth. The material to use should be something that will to form bone. The HA and calcium sulfates only allows bone to form on it and has NO osteoinductive ability. The body needs help to form the new living bone The major function or the body after an injury is TISSUE REPAIR and not tissue regeneration.

Calcium phosphate (CaPO4) materials have been suggested to possess several interesting properties in the context of bone forming materials: •Similarity in composition to bone mineral. •The ability to form carbonate hydroxyapatite on their surfaces. •The ability to promote cellular function and expression leading to formation of a strong bone–CaPO4 biomaterial interface. •Provision of an appropriate scaffold for bone formation. •The ability to bind and concentrate endogenous bone morphogenetic proteins. Chemical analyses have shown that the biological apatites in enamel, dentin, and bone are not pure hydroxyapatite but contain ions such as CO , HPO , F , Cl , Mg2+, Na+, or K+ and some trace elements (Sr, Zn). The bone mineral known as calcium hydroxyapatite, [Ca10(PO4)6(OH)2] is indeed a carbonate hydroxyapatite by the formula: (Ca, Mg,Na)10(PO4HPO4CO3)6(OH)2. Incorporation of different ions is associated with changes in morphological features of crystal size and shape and in the dissolution properties of the apatite. Thus, substituted ions, such as Mg2+ and CO , are suggested to cause reduction in the crystal size of the apatite with enhanced dissolution rate of the apatite. Hydroxyapatite and glass ceramics are considered as bioactive materials. Bioactivity is referred to as the 'characteristic of an implant material which allows it to form a bond with living tissues' .Bioactive materials are suggested to be osteopromotive (class A) or osteoconductive (class B). While the former have been suggested to allow colonization of their surfaces by osteogenic stem cells at the implantation site subsequent to insertion, the latter allow only bone ongrowth. According to this classification the synthetic hydroxyapatite is designated as a class B bioactive material and glass-ceramic is designated a class A material. Bioactivity has been associated with materials allowing the formation of carbonate hydroxyapatite on their surfaces when immersed in simulated body fluid .Microcrystals identified as carbonate hydroxyapatite have also been observed in conjunction with CaPO4 materials which have been implanted in bone as well as in soft tissues .Bioactive biomaterials develop direct, adherent, and strong bonding with the bone tissue. A number of interfacial bonding mechanisms have been proposed for CaPO4 ceramics such as epitaxial crystal growth, chemical bonds, and mechanical interlocking of resorbable CaPO4 ceramics with bone. A serious aspect of these materials is the propensity of them to contribute to established infection.

Anyone with a good knowledge of the literature should know that B-TCP is garbage. Most people are throwing the TCP out and not using it in Gem 21. They are mixing the PDGF with real bone graft material rather then the TCP. Most of the literature shows that TCP is: An inert biocompatible fill material which serves as a nidus or scaffold for bone formation TCP resorbs very slowly and unpredictably over a period of years rather then months. TCP for defect fill next to a tooth usually results in a mixture of bone, osteoid, and fibrous encapsulation and not true regeneration as seen in the Bowers DFDBA study's TCP usually results in healing by a long junctional epithelium. My advice to anyone doing sinus lifting review Wallace or Delfabrio articles (Meta-analysis). In my practice I use mineralized products for sinus lifting which is either Lifenet FDBA, Puros, regereform, or Bio-oss. I even had great success with C-graft with great histo, not sure why C-graft has fallen out of favor. If you want to live a nightmare wait till one of your TCP/sinus grafts goes bad. Dr. T

Sir, will you please kindly read the interview with Dr. Robert Horowitz on this site (http://www.osseonews.com/bone-augmenation-and-ridge-preservation/).I guess that he is one of the scientific leaders of your specialty.By the way, TCP resorbs much more quickly in comparison with other calcium phosphate ceramics.Thank you.

Dear Dr. Jafari, I am familiar with Dr Horowitz work and know that he is a big fan of B-TCP. I fully respect Dr. Horowitz work. But take a poll on most Periodontist researchers in the field and they will tell you TCP is garbarge. Even Mellonig, who was involved in the Gem 21 studys, will tell you that people throw the TCP out in the Gem 21 and just use PDGF with a better bone graft material. I have used TCP and found it not to do what you say. It certainly doesnt resorb quickly. That brings me to your comment on the interview you wanted me to read. That interview Horowitz is talking about is mostly on SOCKET PRESERVATION not sinus surgery or ridge augmentation. Anyone who reads the studys knows that a socket model is not a good model to test a graft material because anyone can grow bone in a socket. Becker tried the same augument once using a socket model on DFDBA and was REFUTED by both Towle and Bowers for it or was it Mellonig I cant remember :). Dont take my word on it do a pub med search on the point/counterpoint its entertaining. Using TCP in a Socket is not a good model to prove the efficacy of a graft material. If you also read his interview with an astute eye you will take notice that he mixed the tcp with Calforma (calcium sulfate) so I question how much tcp is used, and by the why he covered it with a membrane. Calforma by itself in a socket will form bone. A membrane by itself over a socket will form bone. A Socket by itself will form bone. Get my point...once again a Socket model is a bad model to prove the efficacy of a graft material. Here a study with TCP in the sinus: Horch HH, Sader R, Pautke C, Neff A, Deppe H, Kolk A. Department of Oral and Cranio-Maxillofacial Surgery, Technical University of Munich, Klinikum rechts der Isar, Ismaninger Strasse 22, D-81675 Munich, Germany. horch@mkg.med.tu-muenchen.de The aim of this study was to investigate the long-term effect of the ceramic beta-tricalcium phosphate (beta-TCP) at different sites of alveolar reconstruction and to evaluate its properties. From 1997 to 2002, beta-TCP was implanted as bone substitute in 152 patients using a standardized study protocol. Main indications were the filling of large mandibular cysts (n=52), secondary and tertiary alveolar cleft grafting (n=38), periodontal defects (n=24) and maxillary sinus floor augmentation (n=16). For defects exceeding 2cm in diameter, beta-TCP was combined with autologous bone taken from the retromolar area, the maxillary tuberosity or the chin region. A radiological, clinical and ultrasonographical examination was carried out 4, 12 and 52 weeks postoperative. In 16 cases, biopsies were taken after 12 months indicating complete bony regeneration. While wound-healing disturbances occurred in 9.2% of cases, partial loss of the bone substitute material was found in 5.9%, while total loss occurred in only 2%. Complete radiological replacement of beta-TCP by autologous bone was found after approximately 12 months, indicating its osteoconductive properties. Because of its versatility, low complication rate and good long-term results, synthetic, pure-phase beta-TCP is a suitable material for the filling of bone defects in the alveolar region. Sounds great but: Wound healing distubances 9.2% Loss of bone substitute 5.9% Complete loss 2% Hmmmmm thats alot of % problems.....Oh and I love this one "Complete radiographic replacement of the B-tcp in 12 months." How can you tell by a radiograph that the TCP is replaced by bone? Lets do a bilateral sinus study comparing TCP alone vs FDBA alone? I doubt you will see the % problems on the FDBA side. I stand by my original statement: "Most of the literature shows that TCP is: An inert biocompatible fill material which serves as a nidus or scaffold for bone formation TCP resorbs very slowly and unpredictably over a period of years rather then months. TCP for defect fill next to a tooth usually results in a mixture of bone, osteoid, and fibrous encapsulation and not true regeneration as seen in the Bowers DFDBA study’s TCP usually results in healing by a long junctional epithelium." Thanks for pointing out the interview.

While some of the preceding statements have an element of truth to them, they reflect a lack of understanding of the range of calcium phosphate materials. First, most of the TCP materials are either not completely TCP or are not phase pure. Some will contain HA and others will contain both alpha- and beta- forms of TCP. This will wildy alter the resorption rates and biological response. One of the only true pure phase beta TCPs available is from Curasan (Cerasorb, Cerasorb M). I was a part of the socket protocol with Dr. Horowitz (just submitted for publication) and I can relate that my experience using the faster resorbing Cerasorb M has been outstanding. As with any graft material, the number of walls in a defect and rate of angiogenesis will determine the rate of new bone growth. The problem remains; clinicians who use these materials must know the indications, chemistry, rate of resorption, and biology of the defect before the product can be used predictably and consistently. We are now doing the clinical trials with new TCP blocks of varying porosity. We are hopeful that, ultimately, we will be able to do away with autogenous block grafts for a more minimally invasive methodology (including CAD-CAM milling for ideal architecture - presented Academy of Osseointegration, March 2006)

I am a big believer of academic discussion since it will bring answer to questions and it takes us back to the review of protocols. But I dont respect using heavy language or being rude since we are colleagues! 1. In this blog I see some people using their names and being corteous and see other people using nicknames and calling an excellent High tech material "Garbage". I have been using BTCP for the last three years in different applications in implant dentistry, I have used a great deal of materials in my practice and I happen to do my homework! I take cores with my trephine and send it to the histology lab! I have done that with Puros, with grafton, with Bio Oss, Osseo, BTCP (the material in question) but specifically Cerasorb, a pure phase BTCP, etc. An I have got mixed results. I have done it in sockets and I have done it in sinus areas. As of today I use cerasorb in sinus areas, the results are excellent, clinically and histollogically, I dare any of you to use the material following the indications and do the cores and then speak, but speak with facts not just with theory gathered from papers, do your own homework!!. We have an ethical obligation to use this blog for academic growth and not for vendettas again companies or among ourself! I would encourage you MR Piezo to use your name, just like I did, or Dr Miller did or Dr Callan. You can call a material garbage, you used the same word in front of me at a meeting while we were talking to some Drs after a lecture and I told you it wasnt right to do that! that is why you have so many problems right now with many of your colleagues! I encourage all of you to go back to the original question of the case of Dr N and try to encourage him to give more clinical information about the case in question so he can grow academically which is the idea of this blog! then we go from there and will advice him in the way that he should go when doing an specific procedure or using an specific material. And please, use your names, what are you afraid of?

Correction I mean Dr Perioplastic surgeon!!

What I have seen histologically in pure phase BTCP is really nice, I have seen new bone formation from the inside of the material and a very nice progressive resrption of the material as the bone is being formed, I cant say the same of some other materials since they remain on site longer than needed. As a clinician, I want my graft material to get there, support the site (maintaining de space)and be there for as long as needed, then resorb! what I want is the site to be replaced by bone, so I can place my implants; I dont want any remnants in the area, I want the site to look nice and clean with living bone! iF PURE PHASE BTCP is doing it for me, then I use it! there are new materials in the horizon, but in the mean time, my sinuses, specially in supracrestal technique are being performed with pure phase BTCP. Do whatever you want or feel right, but in the process of trying new materials, get your 2mm core, just like Bob Horowits does and do your own homework! If the Drs that ask the questions are call ignorants because they dont know what you know or because they are in that learning curve that we all were at some point, then we kill the whole purpose of the blog which is encouraging people to grow academically and clinically in implant dentistry. Yes, we need to know biology, and physiology etc, but it all takes time, and we need to mentor this people, we cant scare them! please be more inviting and nice among ourself!

thanks a ton Alvaro Ordonez , for your encouraging commnents, that is the way i also feel so, that blogs are not made to critesise or penalise collegues but to instead encourage them , and grow together in this noble profesion.

Dear Dr. Ordonez, Last I checked we lived in a free country that entitles free speech. I am not paid by the company nor do I have research interest in the product so I can speak freely as to what the published literature has showed on TCP and from my own personal experience with the product. I to take plenty of cores and speak from experience. I apologize if I seemed somewhat harsh but it seems some of us on these boards try to push products that they have research or financial interest in (Which I am not saying you do and I do appreciate your comments). People can benefit from these board by seeing both sides of the fence so to speak. Just telling one side of what you think is great "High tech material" may not be everyones experience and is narrow sited. Not to say that TCP doesnt work great in your hands, it may not work great in others. But to say, " I dare any of you to use the material following the indications and do the cores and then speak, but speak with facts not just with theory gathered from papers, do your own homework." The above statement goes against everything that EVIDENCE BASED DENTISTRY IS ABOUT. Evidence based dentistry is exactly what you are saying not to do. You dont gather your evidence by what someone tells you they got in a core from a blog site. You pull evidence from Published peer reviewed papers showing the data and do the "Homework" from the published evidence. If your cores are what you say they are I look forward to the published article. Until that time I will stand by what the evidence shows about TCP: An inert biocompatible fill material which serves as a nidus or scaffold for bone formation TCP resorbs very slowly and unpredictably over a period of years rather then months. TCP for defect fill next to a tooth usually results in a mixture of bone, osteoid, and fibrous encapsulation and not true regeneration as seen in the Bowers DFDBA study’s TCP usually results in healing by a long junctional epithelium. Once again I apologize for coming off nasty and will tone it down. Look forward to better debates in the future and more courteous commentary, as I agree with Dr. Ordonez we can all grow academically from this site.

Sir, I am not sure if whom you are mentioning, but if it is me, then I would like you to know that I live and practice in a third world country. As far as I know, none of the scholars belonging to the third world countries are considered as "scientist" or "researcher" in highly developed industrial societies. At the best circumstances, we are all looked at as "good consumers" of the products of Hi-Tech companies, and of course, nobody pays a consumer, even a good one, for propagation. My best regards and appreciations.

It seems some of our colleagues went out of proportions.I am a believer in evidence based dentistry yet one has to digest the huge data which is out there and learn about the structure and indications for using each material.Talking on BTCP one has to know that there are big differences between different TCP's.The pure BTCP Cerasorb is different than his successor the CERasorb-M.Most of you have read my sinus studies done with various grafting materials-I have done more than 100sinuses with pure BTCP with high satisfactory results the same as Dr Ordonez and Dr Miller.Histology show remodelling with graft resorption and new bone formation.

Having used only Tcp products in all my grafts (including sinus grafts) for the last 4 years (2 or 3 times a week) I can assure you these materials have moved on and are the future.Although I have only placed implants for 17 years my collegue has done so since 1964 and has seen it all. These newer products ( ever growing range) do resorb in less than 6 months in some patients are very well tolerated and provide an exelent stable enviroment for the body to do its job. I have over 2,000 case photographs of cases using these materials ,in some extreme situations (no buccal bone to the last thread )and the only remarkble thing is the great sucess. In sinus grafts the most notable aspect is absolutely no post op pain not even one ibuprofen needed, why , no foriegn body response a stable sealed lateral window possibly. Things move on these are not the type of TCP used in the 80s and 90s ,a lot has been learnt about them. There is and 5 year study recently done at Liverpool University (Mcgee et al) on a bilateral Sunis graft, one TCP and One Allograft and the core sample of the TCP graft is substantially better than the allograft. Bottom line is what would you have if you needed the graft on yourself,from my experience I know what I would have. Sure the Bmps(BMP2) are a big future but there are issues all we are doing is helping the body to heal and suppling the stable conditions and the nutrients for it to do so.

Sorry as to the original question, do not worry as the radio opacity can decrease at the 2 to 4 or 5 week timescale but will increase again.Again not sure of the type of material so things could vary. A major issue in these materials is they are operator sensitive and must be used according to manufacturer recomendations.

Here is the bottom line. Start with the end in site. Do you want a graft material that looks good on xray, one that resorbs and is replaced by vital, remodelable, alveolar bone, or one that is simply a scaffold on which new bone can form, potentially interfering with resorption of the inital graft material? My suggestion to you is to do what many of us "researchers" do. Take some samples of the material that you have placed at the time of implant placement. Send them to Dr. Michael Rohrer and his staff at the Hard Tissue Research Lab at the U. of Minnesota and see what results you get. The studies that Dr. Mazor, Dr. Miller and I have done and are continuing to do give us valuable research on the materials we use in the way we use them. Our criteria, as has been stated by other "bloggers" is vital bone. After all, if the resulting conglomerate has a non-vital, non-resorbing material in it and there are no osteoclasts visible on histologic analysis, can the "bone" resorb and remodel to the body's stresses placed upon the system during function and/or parafunction? Again, determine your criteria for successful grafting and then study what you are doing. As far as the dentist in a "third world country" the only difference between a consumer and a researcher is the level of analysis put upon the result. As far as throwing out the TCP in Gem 21S, that is personal preference as to which carrier the surgeon wishes to use. More studies are needed on this and future "growth factors" to determine the mode of action which will determine the ideal carrier for each. Unfortunately, those steps are limited by the companies funding (or not) research and the FDA's control. Sincerely, Bob Horowitz

I truly accept your apologies Dr Perioplastic surgeon, and hopefully we will continue this discussion as colleagues and I am looking forward to meet you! you seem a knowleadgeable smart guy! I am a believer in evidence, and I am a user! I am a user that wants to see the evidence! but you and me know (if you have been involved in research) that a great deal of info is bias by the industry! thats why after reading the evidence and deciding that the evidence makes sense that then I go ahead and double check myself if what I read and or heard at the lecture is true! (since I am an skeptic reader/ listener/ user) in the process of doing that, we double check the evidence and we create new evidence! it is called clinical research! it is more difficult and as important as basic research! I believe that what is coming next is some of you that are skeptic of the material in mention to try it! wait a few month, take a core, read the sample and get back to this same site! and we talk about it again! As for potential infections in the sinuses, of course I have had three or four minor infections in the sinuses, anyone who hasnt have one, then he hasnt done enough sinuses. and I have had it with different materials, for whatever reason, call it learning curve (trying different techniques), call it case management and selection, call it infection control. It happens and it will most likely happen again! I will continue using Pure Phase Beta TCP, and also DFDB, and autogenous etc because they are great materials, specially in the sinuses; I do a great deal of crestal sinus approach (ISM) and for that purpose radiographic visualization of the material is specially good to asses not only containment of the graft material but also evolution of the "maturity" of the graft itself. For that purpose I like the resorbability of the pure phase BTCP and the histological results that by the way look similar to the results of smiler, horowitz, miller etc, what a coincidence that we all in different parts of the world are getting the same results clinically and histologically. I have to admit in a humble manner that in my learning curve of using Pure phase BTCP I did condense the material in one oportunity and had a complication! it wasnt the material that failed, it was me condensing a material that is hollowed microscopically and that its not made and intended to be condensed, it has to be carried in to the surgical area pasively without altering the constitution of the material. with this one, I say good by to all of you, and wish that we treat each other in a very nice and friendly way even if we screw up! eventually I will bring myself a complication asking for help and you will guide me into the solution, instead of making me feel worst than how I would be feeling! Or sometimes asking questions can be a little embarrasing! so dont spank me in the process of answering, please guide me as friends, brothers and colleagues so I can learn from your knowleadge. sincerely Dr Ordonez

Thank you for all the comment and interaction in response to Dr N`s inquiries.I would encourage him to persist in asking questions and not be intimidated. I am also practising in a 3rd world situation and have been using Synthograft in my lateral sinus lifts.This is a pure phase beta TCP and works very well in a multi-walled situation. As with everything imported and subject to foreign exchange rates,it is costly for the patient.Is there no way of obtaining large volumes of REASONABLY PRICED pure phase betaTCP?

Pieter, you may try ordering medical grade from a pharmacy. Make sure it has brushite as a component.