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Nanopharmaceuticals in Alveolar Bone and Periodontal Regeneration
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Mark A. Reynolds, Zeqing Zhao, Michael D. Weir, Tao Ma, Jin Liu, Hockin H. K. Xu, Abraham Schneider
To address these problems, filler particles were added to bonding agents to increase the load-bearing ability of the adhesive resin, minimise the shrinkage due to polymerisation, and render a stronger resin-tooth interfacial bond (Belli et al. 2014; Hikita et al. 2007). Moreover, to make resins that have remineralisation ability, calcium phosphate fillers were added to the resins. The release of calcium (Ca) and phosphate (P) ions favoured hydroxyapatite (HA) precipitation and caused dental lesion remineralisation (Dunn 2007). Nanoparticles of amorphous calcium phosphate (NACP) were made using a spray-drying facility and loaded into dental resins (Xu et al. 2006). Notably, the NACP composite provided the releases of Ca and P ions that matched conventional CaP-resin composites; however, the NACP composite exhibited much greater load-bearing properties (Xu et al. 2010).
Pathogenesis: Molecular mechanisms of osteoporosis
Published in Peter V. Giannoudis, Thomas A. Einhorn, Surgical and Medical Treatment of Osteoporosis, 2020
Anastasia E. Markatseli, Theodora E. Markatseli, Alexandros A. Drosos
Individuals take calcium from food. Calcium is absorbed from the intestine, and the amount of calcium that is not used to rebalance its concentration in the blood moves to the bone. There, together with phosphorus, it is converted to either amorphous calcium phosphate available for every need or the crystalline form of hydroxyapatite. Calcium that is not absorbed from the intestine will be expelled from the feces. Furthermore, a percentage of calcium that will be filtered in the renal tubules will be reabsorbed. This process is primarily regulated by the concentration of plasma calcium. Since the skeleton retains approximately 99% of the total calcium in the body, the processes of bone formation and resorption are reflected in the variations seen in plasma calcium concentrations and in urine-excreted calcium levels (69–71). Calcium not retained in the skeleton (1% of the total body calcium) remains mainly in the extracellular fluid. It is found in active ionized form by approximately 45% when the concentration of plasma proteins is normal.
Chemical, Biochemical, and Medicinal Properties of the Diphosphonates
Published in Richard L. Hilderbrand, The Role of Phosphonates in Living Systems, 2018
Marion D. Francis, Raymond R. Martodam
Heterotopic ossification is also a frequent complication of spinal cord injury. Extensive involvement may cause a severe limitation of motion due to ankylosing of the joints. An inflammatory reaction precedes the deposition of amorphous calcium phosphate which is gradually replaced by enlarged hydroxyapatite crystals. HEDP is effective at reducing the number of patients who get heterotopic ossification and its severity following spinal cord injury (see Figure 9.)37 If HEDP is administered after there is radiographic evidence for heterotopic ossification, further ossification is retarded. One year after termination of treatment, a follow-up study showed that patients who had received HEDP still had significantly less heterotopic ossification than the placebo group.37 The best results are obtained if the drug is given before there is any evidence of heterotopic ossification.
Osteogenic and Angiogenic Synergy of Human Adipose Stem Cells and Human Umbilical Vein Endothelial Cells Cocultured in a Modified Perfusion Bioreactor
Published in Organogenesis, 2021
Fatemeh Mokhtari-Jafari, Ghasem Amoabediny, Mohammad Mehdi Dehghan, Sonia Abbasi Ravasjani, Massoumeh Jabbari Fakhr, Yasaman Zamani
All in all, static coculture significantly enhanced osteogenic and angiogenic differentiation at day 14 compared to static monoculture. Due to significant increase in ALP activity and enhanced expression of angiogenic markers, dynamic coculture is in preference to static coculture. Dynamic coculture has high priority compared with dynamic monoculture due to enhanced expression of angiogenic markers. Other studies have revealed other aspects of dynamic culture and reported that dynamic mechanical stimuli during the culture period improve the mechanical properties of the tissue-engineered vessels by more collagen and elastin expression within the extracellular matrix (ECM).61 In addition, fluid shear stress has a positive effect on the biomineralization process of tissue-engineered bone, as evidenced by the enhanced degree of collagen self-assembly and the accelerated speed of amorphous calcium phosphate formation and transition.62
Higher early proximal migration of hemispherical cups with electrochemically applied hydroxyapatite (BoneMaster) on a porous surface compared with porous surface alone: a randomized RSA study with 53 patients
Published in Acta Orthopaedica, 2020
Peter Bo Jørgensen, Henrik Daugaard, Stig Storgaard Jakobsen, Martin Lamm, Kjeld Søballe, Maiken Stilling
25 patients received a cementless Exceed cup (Exceed ABT RingLoc-x shell) size 50-62 mm, and a cementless Bi-Metric stem (Zimmer Biomet). Cup and stem were treated with plasma-spray porous titanium coating with a porosity of 45% and an average pore size of 250 µm (range, 100–1,000 µm), providing a scratch fit (Lindgren et al. 2018). Another 28 patients received similar porous coated Exceed cups (Exceed ABT RingLoc-x shell) size 50–62 mm and Bi-Metric stem (Zimmer Biomet), both with an additional electrochemically applied HA coating (BoneMaster, Zimmer Biomet). The BoneMaster coating consisted of 70% crystalline HA with a thickness of 5 µm and with a 2.0 Ca/P ratio. The amorphous phase in the coating was primarily amorphous calcium phosphate (ACP) but also β-tricalcium phosphate (TCP). All patients received cobalt-chromium-molybdenum modular femoral heads, size 36 mm (1 patient had a size 32), and an E1 highly cross-linked UHMWPE liner (Zimmer Biomet).
Effect of dentifrice containing fTCP, CPP-ACP and fluoride in the prevention of enamel demineralization
Published in Acta Odontologica Scandinavica, 2018
Suzana Carvalho Teixeira Pinto de Souza, Kaline Cassiano de Araújo, Joseane Ribeiro Barbosa, Viviane Cancio, Anderson Araújo Rocha, Mônica Almeida Tostes
Fluoride is the cornerstone of the non-invasive management of non-cavitated caries lesions, but its ability to promote net remineralization is limited by the availability of calcium and phosphate ions [1,2]. The combination of fluoride and a source of bioavailable calcium and phosphate ions have been proposed as an effective treatment for the early stages of caries disease [2,3]. The casein phosphopeptide, amorphous calcium phosphate, is reported to have topical anticariogenic effects due to its ability to stabilize calcium and phosphate in an amorphous state. CPP not only increased fluoride incorporation into plaque, but it also increased the incorporation of fluoride into subsurface enamel and substantially increased remineralization of subsurface lesions of enamel compared with fluoride alone [2,3]. Despite this, in vitro enamel remineralization models have been widely used for prediction of the anti-caries efficacy of CPP-ACP treatment, but the results remain inconsistent [4–11]. The combination of CPP-ACP and fluoride has demonstrated better results in demineralization prevention than CPP-ACP alone [5,8,10].