Rapidly-Dissolving Silver-Containing Bioactive Glasses for Cariostatic Applications

Abstract

A novel bioactive glass series containing incremental amounts of silver oxide was synthesized, ground down, and subsequently incorporated into a dentifrice for the purpose of reducing the incidence of dental caries and lesion formation. Three glasses were synthesized using the melt quench route: Si-Control (70SiO2–12CaO–3P2O5–15Na2O, mol %), Si-02 and Si-05, where 0.2 and 0.5 mol % Ag2O were substituted, respectively, for SiO2 in Si-Control. The glasses were then ground, sieved, characterized, and dissolved in Tris buffer solution (pH = 7.30) for 6, 12, and 24 h, with the pH of the resultant solution being recorded and the ions that were released into solution quantified. Samples of each glass were subsequently embedded into a non-fluoridated, commercially available toothpaste which was then used to brush resin-mounted lamb molars which, up to the point of testing, had been stored in a 1.0 M HCl solution. Knoop microhardness measurements of the molars were recorded before and after brushing to determine the presence of remineralization on the surface of the teeth (surface hardness loss of 37%, 35%, and 34% for Si-Control, Si-02 and Si-05, respectively, after 24 h). Four oral cavity bacterial strains were isolated through swabs of the inner cheek, gums, and teeth surfaces of three volunteers, and placed on agar discs. Of each glass, 0.5 g was placed onto the discs, and the resultant inhibition zones were measured after 6, 12, and 24 h. Si-05 performed better than Si-02 on two strains after 24 h, while exhibiting similar behavior for the remaining two strains after 24 h; the largest inhibition zone measured was 2.8 mm, for Si-05 after 12 h. Si-Control exhibited no antibacterial effect at any time point, providing evidence for the role of silver oxide as the antibacterial component of these glasses.

Bioactive Glass Applications in Dentistry

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Radiological evaluations of low cost wollastonite nano‐ceramics graft doped with iron oxide in the treatment of induced defects in canine mandible

“…A helpful property of silicate‐based materials is the capacity to be created into diverse mass shapes and structures through high temperature sintering without trading off the biomineralization of the nano‐ceramics. The capability of utilizing silicate‐based materials for bone recovery has been affirmed by various examinations, which reflects the capacity of the material to accomplish direct bonding (biomineralization) with local bone, bringing about positive in vitro and in vivo recovery results 5,21‐24 …”

Bioglass: A New Era in Modern Dentistry

“…Besides above content, it may also contain some of biocompatible and bioactive minerals like: Network modifiers, namely CaO, Na 2 O, and P 2 O 5 , are generally used. 5 However, both CaO and Na 2 O may be replaced with magnesium oxide and potassium oxide, which promote apatite crystal formation. To alter the surface reactions and melting properties, aluminum oxide and barium oxide may be added.…”