Biomaterials bioceramics

Overview of bioceramics and related biomaterials incorporating fluoride ions 281... 

Fluorine is an essential element involved in several enzymatic reactions in various organs, it is present as a trace element in bone mineral, dentine and tooth enamel and is considered as one of the most efficient elements for the prophylaxis and treatment of dental caries. In addition to their direct effect on cell biology, fluoride ions can also modify the physico-chemical properties of materials (solubility, structure and microstructure, surface properties), resulting in indirect biological effects. The biological and physico-chemical roles of fluoride ions are the main reasons for their incorporation in biomaterials, with a pre-eminence for the biological role and often both in conjunction. This chapter focuses on fluoridated bioceramics and related materials, including cements. The specific role of fluorinated polymers and molecules will not be reviewed here. 

OVERVIEW OF BIOCERAMICS AND RELATED BIOMATERIALS INCORPORATING FLUORIDE IONS... 

Table 1. Applications of fluoridated bioceramics and related biomaterials...

Knowledge of the surface structure of CaHAP panicles is fundamentally needed not only in medical and dental sciences but also in application of synthetic CaHAP particles to bioceramics and adsorbents for biomaterials, because the affinity of CaHAP surface to biomaterials is an important factor in all the cases. The surface structure of CaHAP was investigated by various means including infrared (IR) (38,39), NMR (40). TPD (41), and XPS (42). Among these methods, IR spectroscopy is most appropriate for the surface characterization of CaHAP particles. 

As mentioned in paragraph 11.6.1 bioceramics are used to repair defects in the human body. Thus a material from outside the body is brought into direct contact with body tissue without any intermediate layer like the skin. These materials are called implants or biomaterials and can be defined in several ways. Two of these definitions are ... 

Ahn, E., Gleason, N. J., Nakahira, A., and Ying, X Y., Properties of nanostructured hydroxyapatite-based bioceramics. Proa Sixth World Biomaterials Congress 643 (2000). 

There have been significant advances in CBPC-based biomaterials in the last few years, particularly Ceramicrete-based dental cement and dahllite-based bioceramics. 

Regrettably, no biomaterial is known to date that is both mechanically stable and sufficiently osseoinductive classic bioceramics such as alumina or stabilised zirconia are strong but bioinert, osseoconductive hydroxyapatite is mechanically weak and essentially non-resorbable, whereas the even weaker osseoconductive tricalcium phosphate is resorbable (Figure 3.9). 

Zeng, H.T. and Lacefield, W.R. (2000) XPS, EDX and FTIR analysis of pulsed laser deposited calcium phosphate bioceramic coatings the effects of various process parameters. Biomaterials, 21 (1), 23-30. 

Kurzweg, H., Heimann, R.B., Troczynski, T., and Wayman, M.L. (1998) Development of plasma-sprayed bioceramic coatings with bond coats based on titania and zirconia. Biomaterials, 19, 1507—1511. 

Li, H.Y., Xue, K., Kong, N., Liu, K., and Chang, J. (2014) Silicate bioceramics enhanced vascularization and osteogenesis through stimulating interactions between endothelia cells and bone marrow stromal cells. Biomaterials, 35 (12), 3803-3818. 

Sahai, N. and Anseau, M. (2005) Cyclic silicate active site and stereochemical match for apatite nucleation on pseu-dowollastonite bioceramic-bone interfaces. Biomaterials, 26 (29), 5763-5770. 

Bohner M, Lemaitre J, van Landnyt P, Zambelli PY, Merkle HP, Gander B (1997) Gentamicin-loaded hydranUc calcium phosphate bone cement as antibiotic delivery system. J Pharmaceut Sci 86 565-572 Bonfield W, Grynpas MD, Tally AE, Bowman J, Abram J (1981) Hydroxylapatite reinforced polyethylene —a mechanically compatible implant material for bone replacement. Biomaterials 2 185-186 Bonyer E, Gitzhofer F, Bonlos MI (1997) The snspension plasma spraying of bioceramics by induction plasma. J Metals 58-62... 

Radin SR, Ducheyne P (1992) Plasma-spraying induced changes of calcium phosphate ceramic characteristics and the effect on in vitro stability. J Mater Sci Mater in Med 3 33-42 Ramires PA, Romito A, Cosentino F, Milella E (2001) The influence of titania/hydroxylapatite composite coatings on in vitro osteoblasts behaviour. Biomaterials 22 1467-1474 Ravaglioli A, Krajewski A (1992) Bioceramics Materials, Properties, Applications. Chapman and Hall, London... 

The development of contemporary medicine implies the necessity of improvements of biomaterials that have been already applied in medicine, as well as research on possibilities of the introduction of new materials, including, among others, bioceramics. 

B.F, Shahgaldi - Coral graft restoration of osteochondral defects, Biomaterials, 19, 205-213 (1998). J. Kotz, J, Bieniek and A, Bieniek, Application of porous bioceramics in experimental therapy in bone injuries. I Morphological and histological studies in the control animals, Arch. Immunol. Then Experim., 36, 89-96 (1988),... 

As to the biomaterial for human tissue replacement, it is necessary to demonstrate if the material has any effect on the biological properties of the tissue. Bioceramics exhibit some possible toxic reactions due to metal ions leaching from the ceramics, resulting in the tissue dying or heavy reactions. In this experiment, cytotoxicity test, hemolysis test as well as skin irritation were conducted to value the biocompatibility of the porous AI2O3 ceramics. 

Yoshimura HN, Pinto MM, Lima E, Cesar PF. Optical properties of dental bioceramics evaluated by Kubelka-Munk model. In Bose S (ed.) Biomaterials Science - Processing, Properties and Applications in. Hoboken John Wiley Sons 2013. p71-79. 

A bioceramic is defined as a ceramic used as a biomaterial (which is great if you know what a ceramic is). The... 

Chemically Bonded Bioceramics, CBBCs, are mainly found within phosphates, silicates, aluminates and sulphates, as well as combinations of these systems [2], The forming reaction is in most cases a hydration process, where the soUd part, the original powder, reacts with water. The CBBCs are an important but small part of the whole biomaterials field. In Fig. 1 is presented an overview of how the CBBCs can be classified as biomaterials. 

The chemistry including phases formed and the stmctures obtained with chemically bonded bioceramics in contact with hard tissue, facihtate and improve the connection between the biomaterial and biological tissue. In many cases a nano-stmctural integration occurs. Five or six reaction mechanisms have been identified which all contribute to a safe contact zone, chemically and physically [4]. 

The chemically bonded bioceramics exhibit several properties suitable for in-situ in vivo placement in hard tissues. This is based on the chemical, physical and biological features of the biomaterials [4, 5-8]. The chemically bonded bioceramics - especially the materials based on phosphates, aluminates and silicates - exhibit a general nanostructure related to both the crystals and the... 

For even more biological related nanostructural bioceramics, stem cell produced materials are expected. However, a restriction is the time before cells in the biomaterial can be used. That s why combination of nanostructural CBBCs and stem ceU activity is likely in the development of these third generation biomaterials, especially if load-bearing properties are required. 

Dorozhkin SV. Medical application of calcium orthophosphate bioceramics. Bio 2011 1 1-51. LeGeros R. Z. Properties of osteoconductive biomaterials calcium phosphates. Clin Oithop Rel... 

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