Evidence of a complex species controlling the setting reaction of glass ionomer cements

- GeO2 increased the degradability of 0.48-xSiO2, xGeO2, 0.36ZnO, 0.16CaO glasses.
- Increased GeO2 reduced initial GIC viscosity and slowed cement setting.
- Increased GeO2 delayed initial crosslinking of GIC matrix by divalent cations.
- GeO2 had little impact on 24h biaxial flexural strength.
- Complex species proposed as mechanism to delay but not impair GIC matrix formation.