Fluoride release from fluoride-containing materials.

F B de Araujo; F García-Godoy; J A Cury; E N Conceição

PubMed · 9484170

Fluoride release from fluoride-containing materials.

F B de Araujo·F García-Godoy·J A Cury·E N Conceição

Abstract

This in vitro study evaluated the amount of fluoride released from fluoride-containing materials over a period of 28 days. Six disk samples (2.06 +/- 0.06 cm2) were prepared of each material and divided at random into seven groups: Group 1: Chelon-Fil; Group 2: Chelon-Silver; Group 3: VariGlass; Group 4: Dyract; Group 5: Vitremer; Group 6: Vitremer + Scotchbond Multi-Purpose; Group 7: Fuji II LC. The cements were mixed according to the manufacturers' recommendations, placed in plastic molds, and pressed between two glass plates. Paraffined dental floss was incorporated into the cements during setting to serve as attachments. The materials in Groups 3, 4, and 5 were light cured (Heliolux) in two different positions for 40 seconds each. In Group 6, the adhesive was light cured in two different positions on both sides for 10 seconds each. The samples were stored at 100% relative humidity for 24 hours. Each sample was then suspended in individual plastic tubes containing 5 ml of deionized water and submitted to constant agitation at 25 degrees C. The water was changed every 24 hours. Fluoride release was determined at 1, 2, 3, 4, 5, 7, 14, and 28 days after buffering the solution with equal volume of TISAB. Fluoride release was measured with a fluoride ion-specific electrode (Orion 96-09) and an ionanalyzer (Orion EA 940) previously calibrated with standard solutions containing 0.05 to 5.00 micrograms F/ml. Fluoride release was expressed as ppm in solution and micrograms F/cm2. ANOVA and Student-Newman-Keuls tests were used to evaluate the data. The results revealed that Chelon-Fil released significantly (P < 0.001) more fluoride for the first 7 days than all the other products. This was followed by Fuji II LC, which exhibited significantly more fluoride release than the rest of the materials for the same 7 days. At days 14 and 28, Chelon-Fil, Dyract, and Fuji II LC released similar amounts of fluoride that were significantly greater than the other products. Group 6 (Vitremer + Scotchbond Multi-Purpose) released significantly less fluoride than the other materials at all time intervals. Fluoride release for all products at days 1 and 2 was significantly greater than the rest of the time intervals, except for Chelon-Silver, which released similar amounts of fluoride for days 2, 3, 4, and 5. Although significance for the remaining time intervals varied for all materials, all fluoride release decreased from day 1 to day 28.

Explore related subjects

Acrylic Resins Analysis of Variance Cariostatic Agents Cermet Cements Compomers Composite Resins Dentin-Bonding Agents Evaluation Studies as Topic Fluorides Glass Ionomer Cements Methacrylates Resin Cements Resins, Synthetic Silicates Silver Compounds Time Factors Comparative Study Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

F B de Araujo, F García-Godoy, J A Cury, E N Conceição. Fluoride release from fluoride-containing materials.. https://pubmed.ncbi.nlm.nih.gov/9484170/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2005

Glucose permeable poly (dimethyl siloxane) poly (N-isopropyl acrylamide) interpenetrating networks as ophthalmic biomaterials.

Poly (dimethyl siloxane) (PDMS) has been widely used as a biomaterial in ophthalmic and other applications due to its good compatibility, high mechanical strength, excellent oxygen permeability and transparency. However, for use as an artificial cornea, contact lens and in other applications, modifications with hydrophilic functional groups or polymers are necessary to improve wettability for tear protein and mucin interactions and to improve glucose permeability for cellular health. Poly (N-isopropyl acrylamide) (PNIPAAM) is a biocompatible and hydrophilic polymer that has been extensively studied on controlled drug release applications due to its lower critical solution temperature (LCST) phenomenon. In the current work, a composite interpenetrating network (IPN) of PDMS and PNIPAAM was formed to generate polymers with oxygen and glucose permeability as well as improved wettability compared to PDMS homopolymers and greater mechanical strength than PNIPAAM homopolymers. Transparent vinyl and hydroxyl terminated PDMS/PNIPAAM IPNs (PDMS-V and PDMS-OH IPNs, respectively) were successfully synthesized. Transmission electron microscopy images verified the structure of the IPNs. Surface analysis suggested that PNIPAAM was present on the surface as well as in the bulk material. PDMS-OH IPNs generated from a PDMS-OH matrix cured in the presence of solvent had the highest glucose permeability at 10(-7)cm2/s, comparable to that of the native cornea. The LCST phenomenon remained in these materials, although changes were not as abrupt as with pure PNIPAAM. These results suggest that these materials may be further developed as ophthalmic biomaterials or for controlled drug-release applications.

Acrylic Resins↗

PubMed2005

The potential of poly(N-isopropylacrylamide) (PNIPAM)-grafted hyaluronan and PNIPAM-grafted gelatin in the control of post-surgical tissue adhesions.

Poly(N-isopropylacrylamide)-grafted hyaluronan (PNIPAM-HA) and PNIPAM-grafted gelatin (PNIPAM-gelatin), which exhibit sol-to-gel transformation at physiological temperature, were applied as control of tissue adhesions: tissue adhesion prevention material and hemostatic aid, respectively. The rat cecum, which was abraded using surgical gauze, was coated with PNIPAM-HA-containing PBS (concentration: 0.5 w/v%). The coated solution was immediately converted to an opaque precipitate at body temperature, which weakly adhered to and covered the injured rat cecum. One week after coating, tissue adhesion between the PNIPAM-HA-treated cecum and adjacent tissues was significantly reduced as compared with that between non-treated tissue and adjacent tissues. On the other hand, the coating of bleeding spots of a canine liver with PNIPAM-gelatin-containing PBS (concentration: 20 w/v%) resulted in spontaneous gel formation on the tissues and subsequently suppressed bleeding. Although these thermoresponsive tissue adhesion prevention and hemostatic materials are still prototypes at this time, both thermoresponsive biomacromolecules bioconjugated with PNIPAM, PNIPAM-HA and PNIPAM-gelatin, may serve as a tissue adhesion prevention material and hemostatic aid, respectively.

Acrylic Resins↗

PubMed2005

Tethering poly(ethylene glycol)s to improve the surface biocompatibility of poly(acrylonitrile-co-maleic acid) asymmetric membranes.

To improve the surface biocompatibility, asymmetric membranes fabricated from poly(acrylonitrile-co-maleic acid)s (PANCMAs) synthesized by water-phase precipitation copolymerization were tethered (or immobilized) with poly(ethylene glycol)s (PEGs) by esterification reaction. Chemical changes on the membrane surface were characterized by Fourier transform infrared spectroscopy and elemental analysis to confirm the immobilization of PEG onto the PANCMA membranes. The hydrophilicity and blood compatibility of the PEG-tethered PANCMA membrane were investigated by water contact angle, water absorption, protein adsorption, plasma platelets adhesion and cell adhesion measurements, and the results were compared with the corresponding PANCMA membranes. It was found that, after the tethering of PEG, the hydrophilicity of the membrane can be improved significantly, and the protein adsorption, platelets adhesion and macrophage attachment on the membrane surface are obviously suppressed. Furthermore, not only the content of maleic acid in PANCMA, which influences the tethering density of PEG, but also the molecular weight of PEG has great effect on the surface modification of PANCMA membranes for biocompatibility.

Acrylic Resins↗