Study: βTCP outperforms Allograft, Xenograft;authors describe Sclerotic Bone
All particulate grafts have only one purpose: to maintain volume and particulate bone grafts are equivalent for this purpose. Given that all particulate bone grafts (irrespective if they are synthetic or cadaver) maintain volume, this study moved past measuring ridges and set out to find the bone graft that produces the most bone and what kind of bone the different grafts produce. Most previous studies equate bone quality with the amount of new bone produced because the authors lack the ability to distinguish between normal healthy vital bone that has the ability to remodel and adapt, and bone that is pathologic and lacks the ability to remodel and adapt.
The three graft materials were implanted in the skull of a pig, including an ungrafted control, and harvested at 8 and 12 weeks.
- “It was obvious that βTCP granules were deconstructed to a sufficient degree, with signs of both dissolution of the βTCP particles and direct cellular resorption. These granules were predominantly embedded in the newly formed bone which was more interconnected than at 8 weeks, with signs of bone remodeling.”
- “In addition, the bovine and human allograft exhibited osseous integration with mature bone, …though particles seemed relatively intact, almost without evidence of absorption and bone substitution.”
Mellonig proposed the theories that allografts produce bone via osteogenesis, osteoinduction and osteoconduction. While all of these theories have been proven wrong, many professors and clinicians in the US still cling to the false narrative. What is amazing in the US is that while most professors and clinicians limit their research and clinical use to cadaver bone grafts, they still cannot describe how these materials produce bone and are unable to see that the bone produced by cadaver bone grafts is pathologic.
The authors in this study are different for two reasons:
First and foremost, one of the authors is a pathologist. A pathologist is trained to see and understand bone pathology and they see the bone pathology found in osteoarthritis and understand sclerotic bone. While there are hundreds of cadaver histologic studies virtually none of them accurately describe the bone produced because the authors lack the knowledge to understand what they are seeing. Dentists have no training in bone pathology and none of our professors or lectures can tell the difference between woven and sclerotic bone. We are aware of only two other instances where the quality of bone produced by cadaver bone grafts is accuracy described in the literature.
The first accurate description of the pathologic bone produced by cadaver bone grafts was made by none other than Marshall Urist, the orthopedic surgeon/scientist who discovered BMP. Urist was working with dentists at USC and published the following article:
- “The over-riding histologic characteristic of sites implanted with DFDBA or MFDBA was retention of non-vital graft particles within fibrous connective tissue.”
- “DFDBA and MFDBA are resorbed very slowly and apparently do not contribute to osteoinduction. Allografts apparently are not resorbed by osteoclasts and therefore their continued use around dental implants is questioned.”
The second reason why the authors of the current study were able to accurately describe the bone produced by cadaver bone grafts is because they have read our preprint articles on sclerotic bone. We know because they referenced one of our preprints.
Preprint articles were created for research that the established journals refuse to publish, but now many research articles are first published in preprint form to speed the dissemination of information and act as a placeholder for the introduction of ground-breaking knowledge. Our preprint articles were rejected by peer reviewers of mainstream journals, though not on scientific grounds as we only received angry rejection notices citing the audacity to attempt to publish something negative about cadaver bone grafts.
That was many years ago, but now that the profession is recognizing a higher failure rate in sites grafted with cadaver bone grafts and they are looking for an explanation. Well done studies are finding that the only statistically significant variable related to implant loss is grafting sockets with cadaver bone grafts.
However, with the publication of studies that find grafting with cadaver bone grafts are the only statistical significant variable for implant loss (Two Studies Find One Reason for Implant Failure) and the profession’s recognition that bone graft failure is real, when they look for answers they are finding our preprints:
- How Cadaver Bone Transplants Mineralize and Sclerotic Bone Fails has been viewed over 2300 times.
- After Mineralization, Mineralized Freeze-Dried Bone Allograft Particles are Exfoliated but not Resorbed as been viewed over 1300 times.
In the discussion, the authors provided a literature review to support their findings:
“A systematic review analyzed the outcomes of randomized controlled trials of socket grafting procedures performed with flapless extraction of teeth after a minimum healing period of 12 weeks. The mean histologic outcomes at or beyond the 12-week re-entry period revealed the highest vital bone content for sockets grafted with alloplasts, followed by sockets with no graft material, xenografts, and allografts.”
- Clinical and histologic outcomes of socket grafting after flapless tooth extraction: A systematic review of randomized controlled clinical trials.
- J. Prosthet. Dent. 2015, 113, 371–382.
- Jambhekar, S.; Kernen, F.; Bidra, A.S.
- Bone healing and graft resorption of autograft, anorganic bovine bone and beta-tricalcium phosphate. A histologic and histomorphometric study in the mandibles of minipigs.
- Clin. Oral Implants Res. 2006, 17, 237–243.
- Jensen, S.S.; Broggini, N.; Hjørting-Hansen, E.; Schenk, R.; Buser, D.
- Alterations in bone quality after socket preservation with grafting materials: A systematic review.
- Int. J. Oral Maxillofac. Implants 2013, 28, 710–720.
- Chan, H.L.; Lin, G.H.; Fu, J.H.; Wang, H.L.
- After Mineralization, Mineralized Freeze-Dried Bone Allograft Particles Are Exfoliated but not Resorbed.
- Steiner, G. Preprints 2019, 2019040271