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  • 1
    Electronic Resource
    Electronic Resource
    Effects of Bicarbonate on Remineralization of Enamel (1977)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of oral pathology & medicine 6 (1977), S. 0 
    Details
    ISSN: 1600-0714
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Enamel surfaces were demineralized in acetic acid and remineralized in solutions that contained 1.5 nM calcium, 1.0 nM phosphate, and 0.0, 5, 15, and 25 mM NaHCO3, and 0.00 or 5.0 mM NaF at pH 7.0. NaF in CO2-free solutions increased the rates of calcium and phosphate uptake during remineralization. Bicarbonate in NaF-free solutions caused small increases of calcium and phosphate uptake. Bicarbonate with NaF in solutions synergistically increased calcium uptake, but did not affect phosphate uptake. Bicarbonate reduced fluoride uptake by about 50 % during remineralization, and increased the Ca/P ratios of deposited minerals from about 1 (dicalcium phosphate) to approach and exceed the ratios of apatites.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0714.1977.tb01798.x
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  • 2
    Electronic Resource
    Electronic Resource
    Electron microscopic appearance of dentin after decalcification and recalcification in vitro (1974)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of oral pathology & medicine 3 (1974), S. 0 
    Details
    ISSN: 1600-0714
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract. Cross-sections of bovine incisor root dentin, 0.2 mm thick, were decalcified by ethylenediaminetetracetate at pH 7.4. After 2-day immersion in recalcifying solution (3.75 mM Ca, 1.67 mM P, 22 mM CO3, 155–160 mM NaCl, pH 7.2, and 28°C) the previously decalcified dentin contained 32 % of the calcium phosphate of natural adult bovine dentin. Electron micrographs showed the deposition of minerals in the previously decalcified dentin matrix after immersion in the recalcifying solution. The matrix near the cemental surface appeared recalcified. Globular appearing mineral deposits occurred in the uncalcified matrix. The mineral deposits in the intertubular matrix apparently indicate sites of nucleation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0714.1974.tb01702.x
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  • 3
    Electronic Resource
    Electronic Resource
    A method of semi-quantitative microradiographic analysis of root surface lesion remineralization (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of oral pathology & medicine 17 (1988), S. 0 
    Details
    ISSN: 1600-0714
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The purpose of this study was to present a modified photometer based digital analysis system for image enhanced microradiographic semi-quantitation of reactions of demineralization and remineralization of root surface lesions. The system was used to determine effects of fluoride on abraded root surface dentin in vitro. Lesions of 30–40 μm depth were produced during 18 h exposure of 180 μm thick single sections in solution of 3 mM Ca (Ca/P 1.67) and 30 mM lactic acid at pH 5.1. Mean mineral content of the lesions was 32% relative to adjacent sound dentin. Exposure of 20 h in the same acid with 5 mM Ca (Ca/P 1.67) and 0.12 mM NaF at pH 6.1 restored the mean mineral content to 76% of normal and increased the resistance of the lesions to demineralization. Remineralization and subsequent demineralization characteristics indicated the growth of fluorapatites on residual minerals in the dentin lesions. The microradiographic analysis system proved to be sensitive and critical in these studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0714.1988.tb01532.x
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  • 4
    Electronic Resource
    Electronic Resource
    On the physicochemistry of plaque calcification and the phase composition of dental calculus (1985)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of periodontal research 20 (1985), S. 0 
    Details
    ISSN: 1600-0765
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The main constituents of human dental calculus are a carbonate containing apatite and a Mg and Zn containing Whitlockite. A third important component is octocalcium phosphate. If the salivary pH is low enough, human dental calculus can also contain dicalcium phosphate dehydrate. According to the physicochemical model of calculus formation, dental calculus must contain calcite as the main component in animals having a high salivary pH.This hypothesis appeared to be valid for a salivary pH of 8 or higher (dogs, miniature pigs, domestic pigs). The physicochemical model implies that resting plaque has certain periods in which it has a higher pH than the saliva and the crevicular fluid in which it is bathed. Literature data provide evidence of such a higher pH, probably caused by proteolysis resulting in the formation of urea, ammonia, and amines by the plaque bacteria. The importance of this mechanism is supported by the fact that protease activity in saliva and dental calculus index are correlated positively (Watanabe et al. 1982). Finally, the importance of saliva as a source of urea and the application of urea rinses in dentistry are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0765.1985.tb00442.x
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  • 5
    Electronic Resource
    Electronic Resource
    Mineral flux of surface enamel and root surfaces in acidified gelatin gels (1984)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of oral pathology & medicine 13 (1984), S. 0 
    Details
    ISSN: 1600-0714
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Gels of crude gelatin were dialyzed to eliminate fluoride, and then acidified with 75 mM lactic and 25 mM acetic acid at pH 4.2 and interfaced with enamel and root surfaces in gel-surface ratio of 0.2 ml/0.15 cm2. Enamel and root surface to gel mineral flux was reduced by initial inclusion of 0.5 and 1.0 mM fluoride with 2.5 mM calcium and 1.5 mM phosphate in gels at pH 4.2. Inclusion of 0.25 mM fluoride in the gels without added mineral ions had no effect in the first 22-day interface. The 0.25, 0.5 and 1.0 mM fluoride remarkably increased remineralization in a second 12-day interface. This indicated that the first fluoride exposure initiated formation of fluorapalites in the enamel which required a lower degree of gel saturation for enhanced remineralization in the second acid exposure. Fluoride had the same effect, but greater effectiveness on enamel than root-surface remineralization. Gels of crude gelatin may contain sufficient mineral ions to alter remineralization-demineralization of enamel and root surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0714.1984.tb01450.x
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  • 6
    Electronic Resource
    Electronic Resource
    Effect of fluoride on ion exchange, remineralization and acid resistance of surface enamel (1979)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of oral pathology & medicine 8 (1979), S. 0 
    Details
    ISSN: 1600-0714
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract. In a system of constant ion activities the rates of F− exchange in enamel, under conditions of exchange alone and remineralization, depended on the concentration of F− in solutions. Acid resistance of surface minerals resulted from exchange of F− for OH− in the enamel at pH 7.0 and 4.5 The leve lof 0.5 mM NaF, compared to 0.05 and 5.0 mM, caused maximum rates of isotopic exchange of 45Ca and maximum acid resistance of enamel. Similarly low levels of F− may be feasible for use in caries prevention in the absence and presence of remineralization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-0714.1979.tb01836.x
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  • 7
    Electronic Resource
    Electronic Resource
    Kinetic reactions of calcium, phosphate, and fluoride ions at the enamel surface-solution interface (1972)
    Springer
    Calcified tissue international 10 (1972), S. 113-127 
    Details
    ISSN: 1432-0827
    Keywords: Calcium ; Phosphate ; Fluoride ; Tooth ; Enamel ; Kinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les surfaces d'émail dentaire sont confrontées avec des solutions de calcium et phosphate, qui y recirculent. Les réactions cinétiques au niveau des surfaces en calcium, phosphate, fluorure et ions hydrogène sont déterminées dans des solutions à concentrations en ions fluor constantes (0.012, 0.025, 0.050, 0.250 ou 0.500 mM/l) et/ou à pH constant (6.8, 7.0, 7.2 ou 7.4). Les vitesses de réactions des ions calcium, phosphate, hydrogène et fluorures augmentent dans les conditions suivantes: 1) augmentation de la surface d'émail, 2) augmentation des vitesses d'écoulement au niveau des surfaces, 3) augmentation du pH de la solution et 4) augmentation de la concentration en ion fluorure. Les vitesses presque proportionnelles des réactions mesurées simultanément indiquent la formation de minéraux apatitiques à la surface de l'émail pendant tout le temps de contact solide-solution.
    Abstract: Zusammenfassung Oberflächen von Zahnschmelz wurden mit konstant zirkulierenden Lösungen, welche Calcium und Phosphate enthielten, equilibriert. Die kinetischen Oberflächenreaktionen von Calcium-, Phosphat-, Fluori- und Wasserstoff-Ionen wurden in Lösungen mit konstanten Fluoridkonzentrationen (0,012, 0,025, 0,050, 0,250 oder 0,500 mM/l) und/oder konstantem pH (6,8, 7,0, 7,2 oder 7,4) bestimmt. Die Reaktionsgeschwindigkeiten dieser Ionen an der Grenze zwischen fester und flüssiger Phase erhöhten sich unter folgenden Bedingungen: 1. Vergrößerung der Schmelzoberfläche; 2. Erhöhung der Geschwindigkeit der der Oberfläche zugeführten Lösungen; 3. Erhöhung des pH der Lösung; 4. Erhöhung der Fluoridionenkonzentration in der Lösung. Die beinahe proportionalen Geschwindigkeiten der gleichzeitig gemessenen Reaktionen deuteten darauf hin, daß auf den Schmelzoberflächen während der ganzen Equilibrierungszeit Apatitminerale gebildet wurden.
    Notes: Abstract Surfaces of tooth enamel were interfaced with recirculating solutions containing calcium and phosphate. The kinetic interfacial reactions of calcium, phosphate, fluoride, and hydrogen ions were determined in solutions of constant fluoride ion concentrations (0.012, 0.025, 0.050, 0.250, or 0.500 mM/l) and /or constant pH (6.8, 7.0, 7.2, or 7.4). The rates of the calcium, phosphate, fluoride, and hydrogen ion reactions at the solid-solution interface increased under the following conditions: (1) increase of the enamel surface area; (2) increase of the rates of solution flow to the interface; (3) increase of solution pH; and (4) increase of the solution fluoride ion concentration. The nearly proportional rates of the concurrently measured reactions indicated the formation of apatitic minerals on the enamel surfaces throughout the time of solid-solution interface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02012541
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  • 8
    Electronic Resource
    Electronic Resource
    Calcium, phosphate, and fluoride deposition on enamel surfaces (1971)
    Springer
    Calcified tissue international 8 (1971), S. 154-164 
    Details
    ISSN: 1432-0827
    Keywords: Calcium ; Phosphate ; Fluoride ; Calcification ; Tooth Enamel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les dépôts simultanés en calcium, phosphate et fluorure et le taux de formation en ion hydrogène, pendant la minéralisation, de surfaces d'émail, attaquées par des acides, sont mesurés du point de vue cinétique dans un système fermé. Le taux de dépôt en calcium et phosphate, à partir de la solution, dépend des concentrations en fluorure et du pH. Les proportions de calcium par rapport au phosphate et de calcium par rapport au fluor suggère la formation de fluoroapatite ou de fluorohydroxyleapatite sur l'émail. L'adjonction d'ions hydroxyles pour maintenir un pH constant au moment du dépôt minéral, dépasse les ions phosphates totaux qui se déposent. Ce fait semble indiquer la possibilité d'une hydrolyse de phosphate acide pendant le dépôt minéral.
    Abstract: Zusammenfassung In einem geschlossenen System wurden die gleichzeitigen Ablagerungen von Calcium, Phosphat und Fluorid sowie die Geschwindigkeit der Wasserstoffionenproduktion während der Mineralbildung an säureverätzten Zahnschmelz-Oberflächen kinetisch gemessen. Die Ablagerungsgeschwindigkeiten von Calcium und Phosphat aus der Lösung hingen von den Fluoridkonzentrationen und dem pH ab. Das Verhältnis von Calcium zu Phosphat und von Calcium zu Fluorid zeigte die Bildung von Fluorapatit oder Fluorhydroxyapatit auf dem Zahnschmelz an. Die Hydroxylionenzugaben, welche nötig waren, um das pH während der Mineralablagerung konstant zu halten, überschritten die totalen, aus der Lösung ausgeschiedenen Phosphationen. Dies weist auf die Möglichkeit hin, daß während der Mineralablagerung eine saure Phosphat-Hydrolyse stattfindet.
    Notes: Abstract Concurrent calcium, phosphate and fluoride depositions, and the rate of hydrogen ion production, during formation on acid etched enamel surfaces were kinetically measured in a closed system. The deposition rate of calcium and phosphate from solution was dependent on the fluoride concentrations and pH. The proportions of calcium to phosphate and calcium to fluoride indicated fluorapatite or fluorhydroxyapatite formation on the enamel. The hydroxyl ion additions to maintain constant pH, concurrent with mineral deposition, exceeded the total phosphate ions deposited from solution. This indicates the possibility that acid phosphate hydrolysis occurs during mineral deposition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02010132
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  • 9
    Electronic Resource
    Electronic Resource
    Evaluation of the calcifying characteristics of biological fluids and inhibitors of calcification (1969)
    Springer
    Calcified tissue international 4 (1969), S. 231-244 
    Details
    ISSN: 1432-0827
    Keywords: Calcification ; Pyrophosphate ; Inhibitors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les propriétés d'induction de calcification des liquides biologiques peuvent être mesurées, in vitro et in vivo, par leur possibilité de redurcir des blocs d'émail décalcifié. Cette propriété est exprimée par les concentrations de calcium (et de phosphate) de solutions synthétiques inductrices de calcification, de concentrations et d'activité connues. Un plasma humain typique a une activité inductrice correspondant à celle d'une solution contenant du calcium, 0,70 mM, Ca/P, 1,67 et fluorure, 0,05 mM. L'activité relativement peu élevée des sérums et des plasmas s'explique par la présence d'inhibiteurs ioniques. L'ion phosphate est l'un d'eux, mais ne peut rendre compte de l'inhibition totale. Des anions et des cations sont responsables de l'inhibition, avec un rôle majeur pour les cations. Les ions suivants, en concentration physiologique, jouent un rôle inhibiteur: P7O 7 4− , HCO 3 − , SiO 4 2− , CrO 4 2− , Mg2+, Zn2+. Un mélange de ces ions provoque une inhibition totale identique à celle du plasma.
    Abstract: Zusammenfassung Der Einfluß biologischer Flüssigkeiten auf den Verkalkungsvorgang kann in vitro und in vivo anhand ihrer Fähigkeit, enthärtete Blöcke von Zahnschmelz wieder zu härten, gemessen werden. Diese Aktivität wird ausgedrückt als Konzentration des Calciums (und Phosphates) synthetischer calcifizierender Lösungen mit bekannter Konzentration und Aktivität. Die Aktivität eines charakteristischen menschlichen Plasmas entsprach derjenigen einer Lösung folgender Zusammensetzung: Calcium 0,70 mM; Ca/P=1,67 und Fluorid 0,05 mM. Die relativ niedrige Aktivität von Serum und Plasma ist bedingt durch das Vorhandensein einer Anzahl ionischer Inhibitoren. Das Pyrophosphation ist ein solcher; er kann aber nicht für die gesamte Inhibition verantwortlich gemacht werden. Sowohl anionische als auch kationische Inhibitoren sind vorhanden, wobei die Kationen den Hauptanteil ausmachen. Folgende Ionen erwiesen sich in einer physiologischen Konzentration als Inhibitoren synthetischer Systeme: P7O 7 3− , HCO 3 − , SiO 4 1− , CrO 4 2− , Mg2+, Zn2+. Zusammengenommen verursachten diese Ionen eine Gesamtinhibition ähnlich derjenigen des Plasmas.
    Notes: Abstract The calcifying activities of biological fluids can be measured,in vitro andin vivo, by their ability to reharden softened blocks of tooth enamel. The activity is expressed in terms of the calcium (and phosphate) concentrations of synthetic calcifying solutions of known concentration and activity. A typical human plasma had an activity corresponding to that of a solution of the following concentration: calcium, 0.70 mM; Ca/P, 1.67 and fluoride, 0.05 mM. The relatively low activity of serums and plasmas was shown to arise from the presence of a number of ionic inhibitors. Pyrophosphate ion is one such inhibitor but cannot account for the major inhibition. Both anionic and cationic inhibitors were shown to be present, with the cations respresenting the major portion. The following ions at their reported physiological concentration were shown to be inhibitors in synthetic systems: P7O 7 4− , HCO 3 − , SiO 4 2− , CrO 4 2− , Mg2+, Zn2+. In combination, these ions caused a total inhibition similar to those for plasmas.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02279126
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