Influence of anti‐washout agents on the rheological properties and injectability of a calcium phosphate cement

Abstract

Anti-washout-type calcium phosphate cement (aw-CPC) was prepared by introducing chitosan, sodium alginate, or modified starch into the powder phase of CPC, respectively. The results showed that these cements cannot be washed out and set within approximately 10-30 min even if the pastes were immersed in distilled water immediately and were shaken in a shaker after mixing and moulding. To our knowledge, it is the first report about the influence of the content of these anti-washout additives on the rheological properties and injectability of the cement. Moreover, novel approach of yield stress measurement was used to evaluate the injectability of the pastes. A modified starch was originally used as anti-washout agent for CPC. This study provided a convenient way to use the injectable CPC with good anti-washout performance when the paste was exposed to blood. The aw-CPC had potential prospects for the wider applications in surgery such as orthopaedics, oral, and maxillofacial surgery.

Self-Setting Calcium Orthophosphate Formulations: Cements, Concretes, Pastes and Putties

“…A knitted two-dimensionally oriented polyglactin fiber-mesh was found to be effective in improving load-bearing behavior of a calcium orthophosphate cement for potential structural repair of bone defects [199]. To make the material stronger, fast setting and anti-washout, chitosan might be added [178,344,403,[424][425][426][427][428][429][430][431][432][433][434]. Furthermore, anti-washout properties might appear by adding sodium alginate [435].…”

Composition and Setting Reaction

“…Most methods involve immersion of the unset cement in a liquid [24,52,58]. Agitation [82] or freeze drying [52] is then employed to disrupt the cement; alternatively the cement is sprayed with air from a specified distance [68]. The amount of material lost is then determined using photography [68] or quantified using a gravimetric method [52,82].…”

“…Washout refers to the tendency of a freshly prepared cement paste to 'disintegrate upon early contact with blood or other fluids' [82]. Washout can be measured using different methods.…”

“…Agitation [82] or freeze drying [52] is then employed to disrupt the cement; alternatively the cement is sprayed with air from a specified distance [68]. The amount of material lost is then determined using photography [68] or quantified using a gravimetric method [52,82]. One of the latest reported methods [37] includes a setup based on Specification CRD-C 661-06 [75] which was scaled down to allow testing of dental materials.…”

Self-Setting Calcium Orthophosphate Formulations

“…A knitted two-dimensionally oriented polyglactin fiber-mesh was found to be effective in improving load-bearing behavior of self-setting formulations for potential structural repair of bone defects [225]. To make the material stronger, fast setting and anti-washout, chitosan might be added [202,389,453,[480][481][482][483][484][485][486][487][488][489][490]. Furthermore, anti-washout properties might appear by adding sodium alginate [491].…”