Osteoinduction

The reconstruction of the periodontal tissue with chitosan was a prelude to the discovery of the osteoinductive properties of chitosan [331]. Surgical wounds from wisdom tooth avulsions were treated with freeze-dried methylpyrrolidinone chitosan that promoted bone regeneration. Methyl-pyrrolidinone chitosan was useful in apicoectomy as well. None of the patients reported adverse effects over three years of observation [332]. 

In spite of these investigations, many reports in the literature demonstrate that these nanoapatite ceramics are not always osteoinductive and, furthermore, do not possess mechanical properties similar enough to bone for sustained osseointegration (Muller-Mai el al., 1995 Doremus, 1992 Du et al., 1999 Weng et al., 1997), criteria necessary for increased orthopedic and dental implant efficacy. Moreover, mechanisms of osteoinduction of calcium phosphate ceramics are not clear and seem to depend on specific nanoapatite material properties (such as surface properties and crystallinity) and the animal tested (i.e., dog versus rabbit). Undoubtedly, the incidental cases of calcium phosphate biomaterial-induced osteogenesis indicate promise in... 

Ripamonti, U., Osteoinduction in porous hydroxyapatite implanted in heterotopic sites of different animal models. Biomaterials 17, 31-35 (1996). 

Yuan, H., Li, Y., Yang, Z., Feng, J., and Zhang, X., An investigation on the osteoinduction of synthetic porous phase-pure hydroxyapatite ceramic. Biomed. Eng. Appl. Bas. Com. 9, 274-278 (1997b). 

Pavlin D, Dove SB, Zadro R, Gluhak-Heinrich J. Mechanical loading stimulates differentiation of periodontal osteoblasts in a mouse osteoinduction model Effect on type I collagen and alkaline phosphatase genes. Calcif Tissue Int. 2000 67(2) 163-172. 

Krause U, Harris S, Green A et al (2010) Pharmaceutical modulation of canonical Wnt signaling in multipotent stromal cells for improved osteoinductive therapy. Proc Nad Acad Sci U S A 107 4147-4152... 

Figure 3.10 Mechanical loading capac- factor. bFGF basic fibroblast growth fac-ity vs. osteoinductive capacity of several tor rhBMP, recombinant human bone mor-...

A similar route was taken by Wang et al. (2014), using polydopamine films to induce the growth of hydroxyapatite on titanium alloy to enhance osteoconductiv-ity. BMP-2 was absorbed onto hydroxyapatite for improved osteoinductivity. The results showed that the conjunction of HAp and BMP-2 increases cell adhesion,... 

Normal bone remodeling processes occur around calcium phosphate cement with osteoclastic resorption removing bone followed by deposition of new bone directly on the resorption line (Yuan et al. 2000). Bone growth on pre-hardened cement situated in muscle tissue suggests that bone cement is osteoinductive. 

Additionally, bone deposition directly onto nonvital matrix provided unequivocal evidence of osteoinduction [31] (Fig. 2). 

A significant striking result is that the bone-inductive activity of TGF-y3 isoforms in the primate is site- and tissue-specific with rather substantial endochondral bone induction in the rectus abdominis muscle but absent osteoinductivity in orthotopic sites on day 30 and limited osteogenesis in orthotopic sites on day 90 (Fig. 4). 

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