scholarly journals Enamel Remineralization and Dentine Tubules Occlusion by Bioactive Formulations Based on Ion-Doped Nanohydroxyapatite and Precursor Nanoparticles.

2021 ◽  
Author(s):  
Andrei Cristian Ionescu ◽  
Lorenzo Degli Esposti ◽  
Michele Iafisco ◽  
Eugenio Brambilla
Keyword(s):  
Health Care ◽  
Calcium Phosphate ◽  
Bioactive Compounds ◽  
Amorphous Calcium Phosphate ◽  
Representative Sample ◽  
Dentinal Tubules ◽  
First Time ◽  
Phosphate Compounds

Abstract Recent health care products are based on formulations claimed to provide enamel remineralization and dentinal tubules occlusion through calcium-phosphate bioactive nanocompounds ( ion-doped hydroxyapatite and precursor nanoparticles). This study aimed to test and characterize for the first time the structure and composition of a representative sample of remineralizing toothpastes and topical mousses available on the market. The enamel remineralization and dentinal tubules occlusion efficacy of tested formulations were investigated in vitro. Formulations were characterized in terms of water- and acid-insoluble fractions, and PXRD, FTIR, and EDS analyses were performed to determine their composition and investigate the presence of bioactive compounds and doping elements. All formulations containing Ca-P bioactive nanocompounds showed remineralizing ability, notably when hydroxyapatite and amorphous calcium phosphate compounds were doped with small amounts of CO3-, F, Mg, and Sr. Topical mousse formulations showed a higher tubules occlusion capability than toothpastes, independently from their composition. In conclusion, all tested formulations could express remineralizing potential both on enamel and dentin thanks to the presence of biomimetic Ca-P compounds. The presence of doping elements or CPP-ACP seems essential to allow such performances.

scholarly journals Evaluation of metallic brackets adhesion after the use of bleaching gels with and without amorphous calcium phosphate (ACP): in vitro study

2013 ◽  
Vol 18 (3) ◽  
pp. 101-106 ◽  
Author(s):  
Sissy Maria Mendes Machado ◽  
Diego Bruno Pinho do Nascimento ◽  
Robson Costa Silva ◽  
Sandro Cordeiro Loretto ◽  
David Normando
Keyword(s):  
Calcium Phosphate ◽  
Bond Strength ◽  
Amorphous Calcium Phosphate ◽  
Shear Bond Strength ◽  
Mechanical Test ◽  
In Vitro Study ◽  
Control Group ◽  
Test Machine ◽  
Tooth Whitening

OBJECTIVE: To evaluate in vitro the effects of tooth whitening using gel with Amorphous Calcium Phosphate (ACP) on the bond strength of metal brackets. METHODS: Thirty-six bovine incisors were sectioned at the crown-root interface, and the crowns were then placed in PVC cylinders. The specimens were divided into 3 groups (n = 12) according to whitening treatment and type of gel used, as follows: G1 (control) = no whitening; G2 = whitening with gel not containing ACP (Whiteness Perfect - FGM), G3 = whitening with gel containing ACP (Nite White ACP - Discus Dental). Groups G2 and G3 were subjected to 14 cycles of whitening followed by an interval of 15 days before the bonding of metal brackets. Shear bond strength testing was performed on a Kratos universal test machine at a speed of 0.5 mm/min. After the mechanical test, the specimens were assessed to determine the adhesive remnant index (ARI). The results were subjected to ANOVA, Tukey's test and Kruskal-Wallis test (5%). RESULTS: Significant differences were noted between the groups. Control group (G1 = 11.10 MPa) showed a statistically higher shear bond strength than the groups that underwent whitening (G2 = 5.40 Mpa, G3 = 3.73 MPa), which did not differ from each other. There were no significant differences between the groups in terms of ARI. CONCLUSION: Tooth whitening reduces the bond strength of metal brackets, whereas the presence of ACP in the whitening gel has no bearing on the results.

scholarly journals Phosphoserine Functionalized Cements Preserve Metastable Phases, and Reprecipitate Octacalcium Phosphate, Hydroxyapatite, Dicalcium Phosphate, and Amorphous Calcium Phosphate, during Degradation, In Vitro

2019 ◽  
Vol 10 (4) ◽  
pp. 54 ◽  
Author(s):  
Joseph Lazraq Bystrom ◽  
Michael Pujari-Palmer
Keyword(s):  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Octacalcium Phosphate ◽  
Ionic Concentration ◽  
Strong Adhesion ◽  
Acidic Conditions ◽  
Rapid Transformation ◽  
Comparable Mass

Phosphoserine modified cements (PMC) exhibit unique properties, including strong adhesion to tissues and biomaterials. While TTCP-PMCs remodel into bone in vivo, little is known regarding the bioactivity and physiochemical changes that occur during resorption. In the present study, changes in the mechanical strength and composition were evaluated for 28 days, for three formulations of αTCP based PMCs. PMCs were significantly stronger than unmodified cement (38–49 MPa vs. 10 MPa). Inclusion of wollastonite in PMCs appeared to accelerate the conversion to hydroxyapatite, coincident with slight decrease in strength. In non-wollastonite PMCs the initial compressive strength did not change after 28 days in PBS (p > 0.99). Dissolution/degradation of PMC was evaluated in acidic (pH 2.7, pH 4.0), and supersaturated fluids (simulated body fluid (SBF)). PMCs exhibited comparable mass loss (<15%) after 14 days, regardless of pH and ionic concentration. Electron microscopy, infrared spectroscopy, and X-ray analysis revealed that significant amounts of brushite, octacalcium phosphate, and hydroxyapatite reprecipitated, following dissolution in acidic conditions (pH 2.7), while amorphous calcium phosphate formed in SBF. In conclusion, PMC surfaces remodel into metastable precursors to hydroxyapatite, in both acidic and neutral environments. By tuning the composition of PMCs, durable strength in fluids, and rapid transformation can be obtained.

scholarly journals Efficiency of Amorphous Calcium Phosphate–Containing Orthodontic Composite and Resin Modified Glass Ionomer on Demineralization Evaluated By a New Laser Fluorescence Device

2009 ◽  
Vol 03 (02) ◽  
pp. 127-134 ◽  
Author(s):  
Tancan Uysal ◽  
Mihri Amasyali ◽  
Alp Erdin Koyuturk ◽  
Deniz Sagdic
Keyword(s):  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Glass Ionomer Cement ◽  
Laser Fluorescence ◽  
Orthodontic Brackets ◽  
Glass Ionomer ◽  
Enamel Demineralization ◽  
Significant Difference ◽  
Resin Modified Glass Ionomer

ABSTRACTObjectives: The aim of this in vitro study was to compare the efficacy of Amorphous Calcium Phosphate (ACP)-containing orthodontic composite and resin-modified glass ionomer cement (RMGIC) on enamel demineralization adjacent to orthodontic brackets evaluated by a new laser fluorescence device.Methods: Sixty extracted maxillary premolars were used in the present study. Twenty orthodontic brackets were bonded with ACP-containing orthodontic adhesive (Aegis-Ortho), 20 were bonded with RMGIC (Fuji Ortho LC) ad20 were bonded with Transbond XT composite as the control. All samples were then cycled for 21 days through a daily procedure of demineralization for 6 hours and remineralization for 17 hours. After this procedure, demineralization evaluations were undertaken by a pen-type laser fluorescence device (DIAGNO-dent Pen). Analysis ofvariance (ANOVA) and Tukey test was used for statistical evaluation, at P<.05 level.Results: According to ANOVA, significant demineralization variations (ΔD) were determined among groups (F=6.650; P<.01). The ACP-containing composite showed the lowest (mean: 8.98±2.38) and the control composite showed the highest (mean:12.15±3.83) ΔD, during 21 days demineralization process (P<.01). Significant difference was also observed between the ΔD scores of the RMGIC (mean: 9.24±2.73) and control (P<.05).No significant differences was found in preventive effects of ACP-containing composite and RMGIC (P<.05) against demineralization.Conclusions: The use of both ACP-containing orthodontic composite and RMGIC should be recommended for any at-risk orthodontic patient to provide preventive actions and potentially remineralize subclinical enamel demineralization. (Eur J Dent 2009;3:127-134)

scholarly journals Comparison of the Efficacy of Different Fluoride Varnishes on Dentin Remineralization During a Critical pH Exposure Using Quantitative X-Ray Microtomography

2018 ◽  
Vol 43 (6) ◽  
pp. E308-E316
Author(s):  
A Sleibi ◽  
A Tappuni ◽  
D Mills ◽  
GR Davis ◽  
A Baysan
Keyword(s):  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Mineral Content ◽  
Test Group ◽  
Control Group ◽  
Mineral Concentration ◽  
Voxel Size ◽  
X Ray ◽  
Casein Phosphopeptide

SUMMARY Objectives: The objective of this in vitro study was to quantify the amount of mineral change in demineralized dentin at pH 5.5 after the application of dental varnishes containing fluoride with casein phosphopeptide–amorphous calcium phosphate, fluoride and bioglass, or fluoride alone. Methods and Materials: A total of 12 extracted human sound mandibular premolar root samples were coated with an acid-resistant varnish, leaving a 2 × 3 mm window at the outer root surface. These root specimens were then randomly divided into four groups and separately subjected to the demineralizing cycle at a pH of 4.8 for five days to create artificial caries-like lesions in dentin. Subsequently, each sample was imaged using quantitative x-ray microtomography (XMT) at a 15-μm voxel size. Each test group then received one of the following treatments: dental varnish containing casein phosphopeptide–amorphous calcium phosphate and fluoride (CPP-ACP, MI varnish, GC Europe), bioglass and fluoride (BGA, Experimental, Dentsply Sirona), or fluoride alone (NUPRO, Dentsply Sirona), as well as a control group, which received no treatment. These samples were kept in deionized water for 12 hours. The thin layer of varnish was then removed. All samples including the nonvarnish group were subjected to the second demineralizing cycle at pH 5.5 for five days. The final XMT imaging was then carried out following the second demineralizing cycle. XMT scan was also carried out to varnish samples at 25 μm voxel size. The change in mineral concentration in the demineralized teeth was assessed using both qualitative and quantitative image analysis. Results: There was an increase in radiopacity in the subtracted images of all varnish groups; a significant increase in mineral content, 12% for the CPP-ACP and fluoride (p≤0.05 and p≤0.001), 25% BGA (p≤0.001), and 104% fluoride alone varnish (p≤0.001). There was an increase in the size of radiolucency in the lesion area with a significant decrease in mineral content in the nonvarnish group, 10% (p≤0.05 and p≤0.001). Conclusions: There was encouraging evidence of a remineralization effect following the application of dental varnish on dentin and also an observed resistance to demineralization during the acidic challenge in all cases. However, a dental varnish containing fluoride alone appeared to have a much greater effect on dentin remineralization when compared with CPP-ACP with fluoride and bioglass with fluoride.

scholarly journals Ultrastructural study of degradation of calcium phosphate ceramic by human monocytes and modulation of this activity by HILDA/LIF cytokine.

1996 ◽  
Vol 44 (10) ◽  
pp. 1131-1140 ◽  
Author(s):  
M D Benahmed ◽  
D Heymann ◽  
M Berreur ◽  
M Cottrel ◽  
A Godard ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Culture Medium ◽  
Marked Decrease ◽  
Calcium Phosphate Ceramic ◽  
Multinuclear Cells ◽  
Residual Bodies ◽  
First Time

Biodegradation of ceramics in vivo is achieved essentially by monocytes and multinuclear cells (osteoclasts). Monocytes are the key element in this process because they intervene first at the biomaterial implantation site during inflammatory reaction. In this work, in vitro studies were conducted on an ultrastructural scale to determine the specific behavior of these cells with regard to a calcium phosphate (CaP) ceramic. Two types of phagocytosis were observed when cells came into contact with the biomaterial: either CaP crystals were taken up alone and then dissolved in the cytoplasm after disappearance of the phagosome membrane or they were incorporated together with large quantities of culture medium, in which case dissolution occurred after the formation of heterophagosomes. Phagocytosis of CaP coincided with autophagy and the accumulation of residual bodies in the cells. Addition of HILDA/LIF factor to these cultures induced a very marked decrease in phagocytotic activity directed at the capture of CaP crystals and culture medium. Autophagy was reduced, and residual bodies were rare or absent. This study specifies the role of monocytes in CaP biodegradation and demonstrates for the first time that HILDA/LIF has a biological effect on this cell line.

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