Sintered Xenograft over Allograft?

The article “Use of Sintered Xenograft Over Allograft for Ridge Augmentation: Technique Note” (J Oral Maxillofac Surg. 2014 Mar;72(3):496-502. Block MS, et al.), describes using sintered xenograft (bovine) over an allograft which decreases resorption of the layered graft because “the sintering process increases the crystallinity of the bone particles, it may not clinically resorb and often will be present years after placement”.

I have a patient that has a cosmetic defect (high smile line) above an upper canine that is replace with a fixed bridge. She asked me to fill in the defect for cosmetic purposes. I feel the sintered graft approach mentioned in the article will offer a long lasting result. Any thoughts on the technique of Sintered Xenograft Over Allograft mentioned in the article? Which sintered xenograft did you use?

28 thoughts on: Sintered Xenograft over Allograft?

  1. docphil says:

    I could be wrong, but I believe that “sintered” simply refers to a manufacturing process using heat, whereby the organic material is removed from the bovine bone. As such, Bio-Oss is a type of sintered xenograft (probably the most famous), as is BioXen. Both of these products are produced by the removal of organic material from bovine bone (i.e. sintering), so either could be used. As for the technique itself of using bovine xenograft over an allograft, I’d have to let others chime in, as I’m not familiar with that approach.

  2. Dr. T says:

    Bio-oss is not sintered. Sintering means using heat (1000 degrees plus) to remove organic components. This alters the crystalline structure making the xenograft look less like human bone. Bio-oss has a proprietary method of removing these organic components leaving the structure of the bone to look like hunan bone. More natural.
    The contour augmentation technique by buser uses bio-oss over autogenous bone to protect from premature resorption.

    • docphil says:

      Thank you for the clarification, I stand corrected. Neither of the 2 xenografts, I mentioned are sintered. I was not aware the temperature is 1000 degrees plus. Out of curiosity how is Bio Oss actually removing the organic components? Have they ever revealed anything about their methods? Just using chemicals?

      • docphil says:

        Just looked at some other xenografts on the market, it looks like Endobon from Zimmer Biomet is sintered. Again I could be wrong (please let me know), but their brochure seems to imply that a two-step high temperature process is used, which sounds like sintering.

    • greg steiner says:

      Dr. T Good comment but Bio-Oss is full of organic material. The heating process for Bio-Oss removes the soft tissue stroma but does not remove the organic matrix in the mineralized component. It is the remaining organic proteins that cause the intense inflammation that results in a more dense mineralization found with BioOss.

  3. Amit Binderman says:

    Sintered or not sintered, xenograft will never “look” like bone since it will never really integrate with the patient’s natural bone. Xenograft is a great space filler. It will be encapsulated with thick cementum and will remain there as an island of foreign substance pretty much forever. Allograft will at least resorb and hopefully will be replaced by new bone if the patient is young and in good health. Optimally autologous cortical bone or autologous dentin graft will provide the best of both worlds. Integrate with the natural bone, or even ankylose to the alveolar bone, then slowly resorb and assist remodeling of new bone.

    • Craig Misch says:

      There are some incorrect statements that should be clarified. A xenograft, like BioOss, will “integrate” with the patient’s own bone – not “cementum”.. This is well documented in numerous histologic studies. Bovine bone mineral is a highly biocompatible and osteoconductive material that allows for deposition of vital bone directly on the surface of the xenograft particles. As such, the particles become integrated into the bone matrix and natural physiologic remodeling process. It is resistant to resorption so it will remain for years in the bone matrix. Allograft particles typically resorb more than xenograft (although cortical allograft particles resorb slower). There is no evidence that allografts would be a better choice than a xenograft for this layered grafting concept. The use of bovine bone mineral for contour grafting is well documented as well as its use to decrease resorption of other graft materials.

      Orsini G, Scarano A, Degidi M, Caputi S, Iezzi G, Piattelli A. Histological and ultrastructural evaluation of bone around Bio-Oss particles in sinus augmentation. Oral Dis. 2007;13:586-593.

      Piattelli M, Favero GA, Scarano A, Orsini G, Piattelli A. Bone reactions to anorganic bovine bone (Bio-Oss) used in sinus augmentation procedures: a histologic long-term report of 20 cases in humans. Int J Oral Maxillofac Implants. 1999;14:835-840.

  4. Andrew W says:

    I believe Bio/oss undergoes several steps to completely de-protinize the bone. Chemical, gamma irradiation, temperature controlled cleaning. Endo In is a sintered bone. The crystalline structure is compromised.
    Bio-oss is actually very similar in shape, size and porosity to human bone under a microscope. That’s what makes it different than other xenografts. If you look at some histologies it incorporates very well with the native bone and helps maintain the volume and structure you need. I combine it with autogenous bone if I can scape some. This helps turn over a little quicker but stops the premature resorption.


    Bio oss is a good space maintainer. It is as far as I know alkaline/heat deproteinized bovine bone keeping a good macro and micro architecture that allows new bone ingrow and aposition over the bio- oss particle.
    As any xenogenic biomaterial it first unchains a mild foreign body reaction mediated by multinucleated giant cells thought earlier to be osteoclasts.
    Due to the cristallinity of it main component hidroxiapatite, it resorbs very slowly therefore the regeneration obtained with Bio-Oss or any similar product is a composite Bone-Biomaterial suitable for most dental implant procedures and as space maintener.
    There are many other biomaterials that can be used for regenerative pourposses such as sinthetic Hidroxiapatite Ha, Tricalcium phosphate Tcp, human derived bone mineral (LDHB), matrix (LHB) or autologous bone or dentin.
    Autologous dentin is a promising source of autologous bone substitute material with good clinical and histological performance.
    Sinthetic calcium sulfate /Tcp Ha composite biomaterials such as Ethoss also perform very nicely.

      • Alex says:

        A clinical histologic study of bovine hydroxyapatite in combination with autogenous bone and fibrin glue for maxillary sinus floor augmentation
        Results after 6 to 8 months of healing

        Mats Hallman,
        Andreas Cederlund,
        Sven Lindskog,
        Stefan Lundgren,
        Lars Sennerby
        First published: April 2001


        Biopsies were taken from 16 out of 20 consecutive referral patients 6 to 8 months after maxillary sinus floor augmentation with a mixture of bovine hydroxyapatite (BH), autogenous bone particles and fibrin glue. Four days prior to biopsy retrieval the patients were given a single dose of tetracyclin to label bone forming sites. Fluorescence microscopy of 100 μm thick sections revealed active bone formation in conjunction with the BH particles in 14 of 15 specimens analysed.

        Light microscopy and morphometry of ground sections from 16 patients showed various amounts of mineralised bone tissue in all except one specimen. In the latter case, the BH particles were encapsulated by a dense fibrous connective tissue. Sections from the augmented areas were occupied by non-mineralized tissue (54.1+12.6%), lamellar bone (21.2+24.5%), BH particles (14.5+10.3%) and woven bone (10.2+13.4%). The non-mineralized tissue seen in bone forming areas consisted of a loose connective tissue, rich of vessels and cells, and in the periphery of a more dense fibrous connective tissue. Woven bone with large and scattered osteocyte lacunae was bridging between the BH particles and the lamellar trabecular bone.

        There were no signs of resorption of the BH particles.

        The lamellar bone appeared to have originated from the recipient site and was seldom in contact with the BH particles. It is concluded that the tested implant material has bone conducting properties. The bone associated with the BH particles after 6 to 8 months of healing was mainly woven.

  6. Peter Fairbairn says:

    Yes there is a lot a sales material driven stuff in Dentistry …. “xenograft looks like human Bone ” …….. when my Histologist ( Professor with 35 years experience in Orthopedics ) first saw a xenograft in a core from us , he was shocked and had to ask what it was . He simply had never seen it before . I through my research get to see a little histology and it is simply not what I have seen .
    As I always say EthOss ( yes I have an involvement , so lets state that up front ) and other synthetics and xenografts are completely different materials . They are , as David alludes to Bone regeneration materials with a high Osteo-inductive potential ( over 200 published papers , most high impact ones ( over 6 , some are 12 ) in Pubmed although will not list them it includes PNAS ) whereas the Xenografts are space fillers which while may offer support to tissues , logically will significantly reduce the amount of true host bone in the site HL Chan HL WAng Systematic Review JOMI ) . So we often evaluate the graft site with a set of calipers but do not assess the more important aspect the Quality of the regenerated hard tissue to assess how much is in fact host bone , so histo-morphometry is the only tool for true success .
    Patients coming to us want to be healed in other words returned bak to a state of health they were in prior to the pathology that caused the bone loss .
    We make these decisions for our patients for the long term hence I prefer our approach of fully bio-absorbed material with osteo-inductive potential to help the host regenerate true host bone . Regards Peter

  7. greg steiner says:

    I agree with Peter. In the case mentioned if it is just esthetics I would advise sintered hydroxyapatite. It is never resorbed so it will maintain shape and is biocompatible so it will not be exfoliated like allografts.

  8. Alex says:

    Cow bone “Bio-Oss” is unresorbable and you can find bovine proteins in it.

    Histologic Findings in Sinus Augmentation with Autogenous Bone Chips Versus a Bovine Bone Substitute.
    Source: International Journal of Oral & Maxillofacial Implants . Jan/Feb2003, Vol. 18 Issue 1, p53-58. 6p. 4 Color Photographs, 2 Black and White Photographs, 1 Diagram, 1 Graph.
    Author(s): Schlegel, Karl Andreas; Fichtner, Gabriele; Schultze-Mosgau, Stefan; Wiltfang, Jörg
    Purpose: The aim of this study was to compare a bovine bone substitute (Bio-Oss) to autogenous bone with respect to its value as a material for sinus augmentation. Materials and Methods: In 10 beagle dogs 12 months of age, the 3 maxillary premolars were extracted on both sides. Six weeks later, 2 cavities of predefined size were produced in the region of the nasal cavity. The antral window was 25 mm long and had a vertical extension of 7 mm. Two Frialit-2 implants (3×8 mm) were placed in each bone defect (n = 20). Every implant was primarily stable because of fixation in native bone. In each maxilla, 1 bone defect was filled with autogenous bone harvested from the mandible and 1 was filled with Bio-Oss (material selected at random). The animals were sacrificed at 90 and 180 days, and histologic specimens were examined and the results subjected to statistical analysis by the Wilcoxon test for paired observations. Results: No healing problems were observed. Histologically, after 90 days the volume of the augmentation showed a reduction of 14.6 ± 4.4% within the Bio-Oss group and 3.8 ± 2.5% in the group with autogenous bone. Bone-implant contact of 52.16 ± 13.15% in the Bio-Oss group and 60.21 ± 11.46% in the autogenous bone group was observed. At 180 days, the Bio-Oss group showed bony in growth of the substitute, whereas in the autogenous group a differentiation from original bone could no longer be made. The volume reduction was 16.5 ± 8.67% in the Bio-Oss group and 39.8 ± 16.14% in the autogenous group. Bone-implant contact of 63.43 ± 19.56% in the Bio-Oss group and 42.22 ± 12.80% in the autogenous bone group was measured. Discussion and Conclusion: The results indicated that because of the nonresorptive properties of the bone substitute Bio-Oss, regeneration of the defects is achievable. It was demonstrated that the bone substitute seemed to behave as a permanent implant. The volume of the area augmented by autogenous bone decreased over the observation period.
    Copyright of International Journal of Oral & Maxillofacial Implants is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder’s express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.

    • Amit Binderman says:

      If the graft doesn’t resorb over time, then you definitely want it to be as close to natural bone as possible. That’s not the case with Xenograft. We too see autologous bone resorb too quickly to maintain mature lamelar bone. That’s why our group advocates tooth graft which is Dentin + enamel (75:25) which offers ALL the qualities of autologous bone, but resorbs very slowly over a few years and absolutely supports formation of mature bone, implant contact and site stability. Tooth graft or dentin graft is tougher than cortical bone and sustains itelf for longer. The results of ankylosis of the dentin graft in the first couple of years will results in excellent bone interface and the longer replacement resorption results will be even better.

      • greg steiner says:

        I have seen histology of dentin grafts and I did not see any resorption of the material. Root tips don’t resorb so why would it resorb when ground up. Do you have any histologic studies showing resorption?

        • Amit Binderman says:

          Hi Greg,
          It could be that the histology that you’ve looked at is too short term. As I’ve said previously, dentin resorbs very slowly. We do have histology that shows that and recently did a small study with Dr. Robert Horowitz on the topic. As for root tips, you are correct that these rarely resorb. However root tips and dentin graft prepared from ground up teeth are two different things. The root tip typically maintains the lining cells / periodontal ligament which inhibits osteoclasts bindings and therefore inhibits resorption. The dentin graft obviously isn’t covered with lining cells due to its processing and therefore it will be attacked by osteoclasts and will exhibit resorption. I think that on the Smart Dentin Graft User Group on facebook there are a few cases that show this process, but I’ll have to search for them.

        • Amit Binderman says:

          Hi Louis. For full disclosure, I am associated with a company, KometaBio Inc., that developed a protocol for converting extracted teeth into tooth graft that contains approximately 85% dentin and 15% enamel. We introduced a device that facilitates this conversion in an easy, safe and predictable manner within 15 minutes chairside. It works amazingly well for short term as well as the long term results. As for the enamel, it is basically Hardened HA and as such it is completely biocompatible, not to mention that it acts as an excellent scaffold with very nice enamel to bone interface. The enamel part of the graft (15%) will not resorb, but will integrate nicely. For articles, studies and research on the topic I can direct you to

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