title: Influence of sodium content on the properties of bioactive glasses for use in air abrasion.
abstract: Air abrasion is used in minimally invasive dentistry for preparing cavities, while removing no or little sound dentine or enamel, and the use of bioactive glass (rather than alumina) as an abrasive could aid in tooth remineralization. Melt-derived bioactive glasses (SiO2-P2O5-CaO-CaF2-Na2O) with low sodium content (0 to 10 mol% Na2O in exchange for CaO) for increased hardness, high phosphate content for high bioactivity and fluoride content for release of fluoride and formation of fluorapatite were produced, and particles between 38 and 80 µm in size were used for cutting soda-lime silicate glass microscope slides and human enamel. Vickers hardness increased with decreasing Na2O content, owing to a more compact silicate network in low sodium content glasses, resulting in shorter cutting times. Cutting times using bioactive glass were significantly longer than using the alumina control (29 µm) when tested on microscope slides; however, glasses showed more comparable results when cutting human enamel. The bioactive glasses formed apatite in Tris buffer within 6 h, which was significantly faster than Bioglass® 45S5 (24 h), suggesting that the hardness of the glasses makes them suitable for air abrasion application, while their high bioactivity and fluoride content make them of interest for tooth remineralization.
authors.affiliation: Dental Physical Sciences, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
authors.forename: Imran
authors.initials: I
authors.lastname: Farooq
authors.forename: Maxi
authors.initials: M
authors.lastname: Tylkowski
authors.forename: Steffen
authors.initials: S
authors.lastname: Müller
authors.forename: Tomasz
authors.initials: T
authors.lastname: Janicki
authors.forename: Delia S
authors.initials: DS
authors.lastname: Brauer
authors.forename: Robert G
authors.initials: RG
authors.lastname: Hill
mesh_terms: D020906:Air Abrasion, Dental / Q000379:methods*; D000537:Aluminum Oxide / Q000737:chemistry; D001031:Apatites / Q000737:chemistry; D001696:Biomechanical Phenomena; D002516:Ceramics / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry; D010316:Particle Size; D012964:Sodium / Q000737:chemistry*; D017670:Sodium Compounds / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001031:Apatites; D003764:Dental Materials; D010087:Oxides; D017670:Sodium Compounds; C425330:bioactive glass 45S5; C096707:sodium oxide; D012964:Sodium; D000537:Aluminum Oxide