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Zameer S, Najmi AK, Vohora D, Akhtar M. Bisphosphonates: Future perspective for neurological disorders. Pharmacol Rep 2018; 70:900-907. [PMID: 30096489 DOI: 10.1016/j.pharep.2018.03.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/05/2018] [Accepted: 03/28/2018] [Indexed: 01/08/2023]
Abstract
Neurodegenerative disorders and osteoporosis share some common underlying pathological features including calcium overload, accumulation of toxic chemicals, inflammation and impaired protein prenylation by isoprenoids (farnesyl pyrophosphate and geranylgeranyl pyrophosphate) appear later stage of life. Substantial number of pre-clinical and clinical reports as well as in vitro data univocally acknowledged the negative impact of altered post-translational modification (prenylation) of proteins like small GTPases (Rffhes, Rho, Rac etc.) and cholesterol levels in both serum and brain on CNS integrity. Bisphosphonates (BPs), referred to as gold standard for osteoporosis treatment, have well established role in attenuation of bone resorption and osteoclast apoptosis by inhibition of farnesyl pyrophosphate synthase enzyme (FPPS) in mevalonate pathway. BPs mainly nitrogen containing BPs (NBPs) have potential to offer new therapeutic targets for neurological disorders and received increasing attention in recent years. A year back clinical and pre-clinical studies revealed that NBPs have the potential to alleviate the symptoms of neurological disorders like brain calcification, Alzheimer's disease and Huntington's disease by targeting mevalonate pathway. Though these drugs have well developed role in inhibition of isoprenoids synthesis, these were demonstrated to inhibit acetyl cholinesterase enzyme and cholesterol synthesis in brain that are considered as the critical factors for impairment of cognitive functions which is the hallmark of several neurological disorders. Still the current understanding of BPs' effect in CNS is limited due to lack of studies focusing the molecular and cellular mechanism. The present review aims to reveal the updated discussion on the mechanism contributing BPs' effect in CNS disorders.
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Affiliation(s)
- Saima Zameer
- Department of Pharmacology, School of Pharmaceutical Education and Research (Formerly: Faculty of Pharmacy), Jamia Hamdard (Hamdard University), New Delhi, India
| | - Abul Kalam Najmi
- Department of Pharmacology, School of Pharmaceutical Education and Research (Formerly: Faculty of Pharmacy), Jamia Hamdard (Hamdard University), New Delhi, India
| | - Divya Vohora
- Department of Pharmacology, School of Pharmaceutical Education and Research (Formerly: Faculty of Pharmacy), Jamia Hamdard (Hamdard University), New Delhi, India
| | - Mohd Akhtar
- Department of Pharmacology, School of Pharmaceutical Education and Research (Formerly: Faculty of Pharmacy), Jamia Hamdard (Hamdard University), New Delhi, India.
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Fan Y, Sun Z, Moradian-Oldak J. Effect of fluoride on the morphology of calcium phosphate crystals grown on acid-etched human enamel. Caries Res 2009; 43:132-6. [PMID: 19321991 PMCID: PMC2814026 DOI: 10.1159/000209346] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Accepted: 01/15/2009] [Indexed: 11/19/2022] Open
Abstract
The aim of this study was to examine the effect of fluoride ion concentration on the morphology of calcium phosphate crystals grown on acid-etched enamel as a model for tooth enamel erosion. Samples were immersed in calcification solution for 16 h and changes in crystal morphology were monitored by field emission scanning electron microscopy. Without fluoride, plate-like octacalcium phosphate crystals (20 nm thick, 2-10 microm wide) were formed. With 1-10 mg/l fluoride, arrays of denser needle-like nanocrystals (20-30 nm wide, >500 nm in length) were formed. We conclude that there is a minimal fluoride concentration (1 mg/l) that dramatically affects the morphology of calcium phosphate crystals grown on etched enamel in vitro.
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Affiliation(s)
- Y. Fan
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, Calif., and
- School of Dentistry, Louisiana State University Health Science Center, New Orleans, La., USA
| | - Z. Sun
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, Calif., and
| | - J. Moradian-Oldak
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, Calif., and
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Berger C, Horrocks B, Datta H. Application of ion-selective microelectrodes to the detection of calcium release during bone resorption. Electrochim Acta 1999. [DOI: 10.1016/s0013-4686(98)00366-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Leamy P, Brown PW, TenHuisen K, Randall C. Fluoride uptake by hydroxyapatite formed by the hydrolysis of alpha-tricalcium phosphate. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1998; 42:458-64. [PMID: 9788510 DOI: 10.1002/(sici)1097-4636(19981205)42:3<458::aid-jbm16>3.0.co;2-c] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Although there is interest in forming synthetic analogs of hard tissues at physiologic temperature, significant gaps in knowledge exist with respect to the mechanisms by which precursor solids convert to apatites and also with respect to the apatite compositions that may be formed. In this study calcium-deficient HAp [Ca9(HPO4)(PO4)5OH] was prepared by hydrolysis of tricalcium phosphate (TCP), alpha-Ca3(PO4)2. The kinetics of HAp formation were studied as a function of temperature by isothermal calorimetry. TCP hydrolyzed completely within about 12 h, and the hydrolysis reaction evolved 133 kJ/mol of HAp formed. Although the kinetics of hydrolysis exhibited a strong temperature dependence, the mechanistic path taken appeared independent of temperature. The fluoridation of hydroxyapatite compositions having Ca/P ratios higher than 1.59 previously has been investigated. However, little work has been done on the fluoridation of more calcium-deficient hydroxyapatite. Ca9(HPO4)(PO4)5OH was formed at temperatures between 37.4 degrees and 55 degrees C to vary its morphology. These preparations then were reacted in NaF solution and the kinetics of fluoride incorporation studied. Solution chemical analyses were used to determine the amounts of fluoride incorporated. The extent of hydroxyl replacement by fluoride ranged from 17 to 72% and correlated with the surface area of the parent HAp.
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Affiliation(s)
- P Leamy
- Department of Materials Science and Engineering, Penn State University, University Park, Pennsylvania 16802, USA
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Abstract
The iron-containing fluoridated hydroxyapatites Fe-FeFAp and FeF-FeAp were synthesized heterogeneously in the presence of ferrous ions at 80 degrees C and pH 7.4 in two different types of solution, i.e. fluoride-free solution during the initial half of the experimental period and fluoride-containing solution during the second half, in the latter of which the fluoride concentration was equivalent to that of fluorapatite. Another experiment was carried out under the opposite conditions. The total fluoride contents of both heterogeneous iron-containing fluoridated apatites were almost the same (0.83 +/- 0.01 and 0.89 +/- 0.02 mmol g-1, respectively). Their X-ray diffraction patterns were not significantly different. However, scanning electron microscopy showed that Fe-FeFAp was composed of clusters of rod-like crystals and FeF-FeAp of bundles of many thin needle-like crystals. Energy dispersive spectroscopy coupled with scanning electron microscopy estimated that the fluoride intensity of Fe-FeFAp was higher than that of FeF-FeAp. The apparent solubility of the former (Ca = 8.83 +/- 0.20, P = 4.27 +/- 0.13 mmol l-1) was less than that of the latter (Ca = 10.8 +/- 0.4, P = 5.56 +/- 0.09 mmol l-1) at 37 degrees C and pH 4.0. These results suggest that two different types of heterogeneous iron-containing fluoridated apatites may be formed.
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Affiliation(s)
- M Okazaki
- Department of Dental Materials Science and Technology, Osaka University, Faculty of Dentistry, Japan
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Wiers BH, Francis MD, Hovancik K, Ritchie CK, Baylink DJ. Theoretical physical chemical studies of the cause of fluoride-induced osteomalacia. J Bone Miner Res 1990; 5 Suppl 1:S63-70. [PMID: 2339638 DOI: 10.1002/jbmr.5650051390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In this study we investigated the possibility of the formation of a calcium fluoride surface film on the new bone matrix in patients undergoing fluoride treatment for osteoporosis. This calcium fluoride film could interfere with the normal mineralization process and lead to hyperosteoidosis (osteomalacia), a well-documented complication seen in fluoride-treated patients. During treatment, fluoride circulating in the blood and extracellular fluid of patients, could interact with the components of the serum, but particularly calcium and magnesium ions. The interrelationships among serum components in the presence of fluoride ion may result, at thermodynamic equilibrium, in deposition on the apatitic bone surface of phases such as calcium fluoride, fluorapatite, or fluorhydroxyapatite. Differences in the phase deposited among patients could result in differences in response to fluoride treatment. A computer program based on equilibrium thermodynamic data was utilized to study the physicochemical calcium, fluoride, and phosphate interrelationships in serum. In all the computer calculations, fluorhydroxyapatite (FHAP), alone or in combination with hydroxyapatite (HAP), was determined to be the thermodynamically stable precipitating surface phase. These data strongly suggest that calcium fluoride surface film is not the reason for the delay of mineralization of fluoride-stimulated new bone. Based on these calculations, we now advance the hypothesis that the effect of fluoride to cause osteomalacia is due to an effect on osteoblasts and also on osteocytes.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- B H Wiers
- Miami Valley Laboratories, Procter and Gamble Co., Cincinnati, OH 45239-8707
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Thomann J, Voegel J, Gumper M, Gramain P. Dissolution kinetics of human enamel powder. J Colloid Interface Sci 1989. [DOI: 10.1016/0021-9797(89)90255-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Gramain P, Thomann J, Gumpper M, Voegel J. Dissolution kinetics of human enamel powder. J Colloid Interface Sci 1989. [DOI: 10.1016/0021-9797(89)90351-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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White DJ, Bowman WD, Faller RV, Mobley MJ, Wolfgang RA, Yesinowski JP. 19F MAS-NMR and solution chemical characterization of the reactions of fluoride with hydroxyapatite and powdered enamel. Acta Odontol Scand 1988; 46:375-89. [PMID: 3213446 DOI: 10.3109/00016358809004791] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Solution chemical and 19F magic angle spinning-nuclear magnetic resonance (MAS-NMR) methods have been utilized to study the effects of fluoride dose, fluoridating pH, and mineral surface area on the dynamics of fluoride reactivity with hydroxyapatite and powdered human dental enamel in vitro. Both solution chemical fluoride uptake and NMR measurements demonstrated that the reaction products of ionic fluoride with apatite include mixtures of FAP, FHAP, and CaF2, with increased amounts of CaF2 promoted by increased F concentration or decreased pH. NMR analysis showed FAP or FHAP as a reaction product of fluoride uptake under all conditions, regardless of whether CaF2 was formed, unambiguously demonstrating fluorite as an additive rather than substitute form of F reactivity. pH stat measurements demonstrated the release of OH- during F reactivity with apatites corresponding to ion exchange formation of FAP/FHAP or dissolution/reprecipitation formation of CaF2. Phosphate release into solution accompanied fluoride uptake under all conditions, including regions where ion exchange predominated. Whereas powdered dental enamel demonstrated fluoride uptake behavior similar to that of synthetic apatite, the resulting reaction products differed as analyzed by 19F MAS-NMR.
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Affiliation(s)
- D J White
- Sharon Woods Technical Center, Procter & Gamble Company, Cincinnati, Ohio 45241
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Surface properties and equilibrium kinetics of hydroxyapatite powder near the solubility equilibrium. J Colloid Interface Sci 1987. [DOI: 10.1016/0021-9797(87)90443-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Okazaki M, Takahashi J, Kimura H. Crystallinity and solubility behavior of iron-containing fluoridated hydroxyapatites. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1986; 20:879-86. [PMID: 3760004 DOI: 10.1002/jbm.820200703] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Iron-containing fluoridated hydroxyapatites with various fluoride contents were synthesized at 80 degrees C and pH 7.4 using FeCl2 X nH2O as a source of iron. The Fe2+ uptake of fluoridated apatites was independent of fluoride concentration in the solution. a-Axis dimensions of Fe-containing apatites decreased with the degree of fluoridation in addition to the decrease related to the substitution of Fe2+ ions. All Fe-containing fluoridated apatites were less well crystallized than Fe-free fluoridated apatites previously reported, although with increasing degree of fluoridation, the crystallinity behavior of the former apatites appeared analogous to that of the latter apatites. In contrast to this inhibited crystallinity behavior, the apparent solubility of Fe-containing fluoridated apatites decreased more than that of Fe-free fluoridated apatites at low fluoride content.
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Okazaki M, Ophaug RH, Singer L. Promotion of bone dissolution by excessive fluoride in acidic buffer solution. Biomaterials 1985; 6:277-80. [PMID: 4052542 DOI: 10.1016/0142-9612(85)90026-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In order to quantitatively examine fluoride uptake by bone and the effect on its chemical and physical properties, rat bone was incubated in acidic buffer solutions (pH 5) with fluoride concentrations of 0-1000 ppm F. After 1 wk incubation, there was a substantial increase in the crystallinity of the bone mineral with increasing fluoride concentration in the solution. The calcium concentration in the solutions used for incubation decreased dramatically, with increased levels of fluoride in the solution, approaching a plateau. The phosphate concentration initially decreased, with increasing levels of fluoride in proportion to the decrease of calcium concentration, and then increased when the fluoride concentration of the solution was above 200-300 ppm. These phenomena, when considered with X-ray diffraction data, reflected the formation of CaF2. The increase of the phosphate concentration in the solution suggests that the presence of excessive fluoride in the acidic buffer solution may promote the dissolution of soluble bone apatites, in spite of the dissolution-preventive activity of fluoride.
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Jarcho M, Dombrowski LJ, Salsbury RL, Bondley BA. Fluoride uptake and dissolution behavior of a synthetic dental enamel-like substrate. J Dent Res 1978; 57:917-21. [PMID: 281369 DOI: 10.1177/00220345780570091801] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A new ceramic form of hydroxylapatite and enamel were found to behave similarly in regard to their acid dissolution behavior in the presence and absence of topically applied fluoride. Discrepancies between the two materials can be explained by morphological differences between the rough enamel and smooth ceramic particles.
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Johnson AR. The effects of inorganic ions situated at the enamel surface on the adsorption and activity of acid phosphatase. J Dent Res 1977; 56:1173-8. [PMID: 272376 DOI: 10.1177/00220345770560100901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This study has demonstrated, first, that the affinity of the enamel surface for a biologically active protein-in this case, acid phosphatase-may be modified by first impregnating the mineral with particular inorganic ions. Second, enzymic activity is altered as a function of the inorganic ion incorporated into the enamel surface. Third, strong inhibition of acid phosphatase is demonstrated by ions expected to be released during the carious process which contradicts the postulation that phosphatases are actively hydrolyzing enamel matrix-bound phosphate during the carious attack. Fourth, these results suggest that by incorporating a particular ion into the enamel mineral, a surface with assigned properties may be created which offers some degree of control over subsequent adsorption of organic matter. Thus, it is apparent that by proper selection of inorganic ions and organic macromolecules, both structural properties and biological activities at the enamel-oral fluid interface may be predictably modified.
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Francis MD, Slough CL, Briner WW, Oertel RP. An in vitro and in vivo investigation of mellitate and ethane-1-hydroxy-1,1-diphosphonate in calcium phosphate systems. CALCIFIED TISSUE RESEARCH 1977; 23:53-60. [PMID: 19135 DOI: 10.1007/bf02012766] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Comparisons of mellitate (MA) and ethane-1-hydroxy-1,1-diphosphonate (EHDP) have been carried out in studies of enamel etching, calcium phosphate crystal growth and animal calculus deposition. In enamel etch studies at pH 5, 6, or 7 and after treatment times of 5 or 170 min, EHDP was less damaging to enamel surfaces than MA as determined by scanning electron microscopy, grazing angle electron diffraction, and quantitative etch solution analyses. Both MA and EHDP inhibited hydroxyapatite crystal growth, although EHDP was more effective than MA. The formation of a tricalcium mellitate surface phase is suggested as the basis of the MA crystal growth effect on apatite. Both MA and EHDP also inhibited rat calculus formation, but EHDP was more effective than MA. The relation between crystal growth inhibition, surface phase solubility, and anti-calculus activity is discussed and a generalized principal for determining an effective inhibitor of calculus is suggested.
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Abstract
One of the major successes of nuclear medicine in recent years has been the clinical utility of the 99mTc-labeled bone-imaging agents. This article is concerned with the evidence available for the mechanisms by which these and other such radiopharmaceuticals localize at sites in the skeleton.
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Misra D, Bowen R, Wallace B. Adhesive bonding of various materials to hard tooth tissues. VIII. Nickel and copper ions on hydroxyapatite; role of ion exchange and surface nucleation. J Colloid Interface Sci 1975. [DOI: 10.1016/0021-9797(75)90080-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Smith A, Posner A, Quirk J. Incongruent dissolution and surface complexes of hydroxyapatite. J Colloid Interface Sci 1974. [DOI: 10.1016/0021-9797(74)90188-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Jung A, Bisaz S, Bartholdi P, Fleisch H. Influence of pyrophosphate on the exchange of calcium and phosphate ions on hydroxyapatite. CALCIFIED TISSUE RESEARCH 1973; 13:27-40. [PMID: 4356313 DOI: 10.1007/bf02015393] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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22
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Robertson WG. Factors affecting the precipitation of calcium phosphate in vitro. CALCIFIED TISSUE RESEARCH 1973; 11:311-22. [PMID: 4350499 DOI: 10.1007/bf02547230] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Gonzalez M, Jeansonne BG, Feagin FF. Trimetaphosphate and fluoride actions on mineralization at the enamel-solution interface. J Dent Res 1973; 52:261-6. [PMID: 4511307 DOI: 10.1177/00220345730520021301] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The presence of trimetaphosphate ions (TMP) in calcium phosphate solutions inhibited the rehardening of softened enamel surfaces. TMP decreased, whereas fluoride increased, the rates of calcium, phosphate, and fluoride reactions with etched enamel surfaces. The mechanisms of action of TMP and fluoride were independent of each other and possibly synergistic.
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Jeansonne BG, Feagin FF. Reactions of enamel surfaces and neutral calcium phosphate solutions after combinations of topical APF and SnF 2 . J Dent Res 1973; 52:348-51. [PMID: 4511318 DOI: 10.1177/00220345730520022601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Etched enamel surfaces were treated topically with combinations of acid phosphate fluoride and stannous fluoride solutions, and then exposed to constantly recirculated neutral calcium phosphate solutions. The calcium, phosphate, fluoride, and hydrogen ion reactions with the variously treated surfaces were compared. Results showed concurrent dissolution of calcium fluoride and diffusion of hydrogen fluoride from the surfaces, and indicated concurrent deposition of apatitic mineral into the surfaces.
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Feagin FF, Gonzalez M, Jeansonne BG. Kinetic reactions of calcium, phosphate, and fluoride ions at the enamel surface-solution interface. CALCIFIED TISSUE RESEARCH 1972; 10:113-27. [PMID: 5083911 DOI: 10.1007/bf02012541] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Gwinnett AJ, Buonocore MG, Sheykholeslam Z. Effect of fluoride on etched human and bovine tooth enamel surfaces as demonstrated by scanning electron microscopy. Arch Oral Biol 1972; 17:271-8. [PMID: 4552623 DOI: 10.1016/0003-9969(72)90210-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Abstract
lnfrared internal reflection spectroscopy (IRS) was used to investigate chemical changes of enamel surface during in vitro remineralization. Specimens were demineralized and exposed either to calcium phosphate-fluoride solutions or to acidulated fluorophosphate. The former showed amorphous phosphate remineralization, and the latter showed surface precipitate interpreted to be calcium fluoride. The significance of previous demineralization time to both forms of remineralization is discussed.
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Francis MD, Webb NC. Hydroxyapatite formation from a hydrated calcium monohydrogen phosphate precursor. CALCIFIED TISSUE RESEARCH 1970; 6:335-42. [PMID: 5553333 DOI: 10.1007/bf02196214] [Citation(s) in RCA: 112] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Koulourides T, Dimitriadis A. Increase in resistance of human enamel to softening by exposure to acid buffers containing calcium and phosphate. Arch Oral Biol 1970; 15:1079-88. [PMID: 5275863 DOI: 10.1016/0003-9969(70)90120-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Newesely H. Factors controlling apatite crystallization, with particular reference to the effect of fluoride and accompanying ions. ADVANCES IN ORAL BIOLOGY 1970; 4:11-42. [PMID: 4914035 DOI: 10.1016/b978-0-12-030504-9.50009-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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