title: Calcium polyphosphate as an additive to zinc-silicate glass ionomer cements.
abstract: Aluminum-free glass ionomer cements (GICs) are under development for orthopedic applications, but are limited by their insufficient handling properties. Here, the addition of calcium polyphosphate (CPP) was investigated as an additive to an experimental zinc-silicate glass ionomer cement. A 50% maximum increase in working time was observed with CPP addition, though this was not clinically significant due to the short working times of the starting zinc-silicate GIC. Surprisingly, CPP also improved the mechanical properties, especially the tensile strength which increased by ∼33% after 30 days in TRIS buffer solution upon CPP addition up to 37.5 wt%. This strengthening may have been due to the formation of ionic crosslinks between the polyphosphate chains and polyacrylic acid. Thus, CPP is a potential additive to future GIC compositions as it has been shown to improve handling and mechanical properties. In addition, CPP may stimulate new bone growth and provide the ability for drug delivery, which are desirable modifications for an orthopedic cement.
authors: Department of Applied Oral Sciences, Dalhousie University, 5981 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada esthervalliant@gmail.com.
authors: Esther Mae
authors: EM
authors: Valliant
authors: Department of Applied Oral Sciences, Dalhousie University, 5981 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada.
authors: David
authors: D
authors: Gagnier
authors: Department of Applied Oral Sciences, Dalhousie University, 5981 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada.
authors: Brett Thomas
authors: BT
authors: Dickey
authors: Department of Applied Oral Sciences, Dalhousie University, 5981 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada.
authors: Daniel
authors: D
authors: Boyd
authors: Department of Applied Oral Sciences, Dalhousie University, 5981 University Avenue, Halifax, Nova Scotia, B3H 4R2, Canada.
authors: Mark Joseph
authors: MJ
authors: Filiaggi
mesh_terms: D002118:Calcium / Q000737:chemistry*; D019245:Compressive Strength; D005899:Glass Ionomer Cements / Q000737:chemistry*; D008422:Materials Testing; D011122:Polyphosphates / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013718:Tensile Strength; D015032:Zinc / Q000737:chemistry*
chemical_list: D005899:Glass Ionomer Cements; D011122:Polyphosphates; D017640:Silicates; D015032:Zinc; D002118:Calcium
keywords: Calcium polyphosphate; bone; composite; glass ionomer cement; minimally invasive