ALUMINUM RELEASE FROM GLASS-IONOMER CEMENTS DURING EARLY WATER EXPOSURE IN-VITRO

Aluminium is a major constituent of glass ionomer cements. During mixi ng and setting aluminium is released from the glass into the polyalkeo nic acid solution. Part of this aluminium may not combine with the pol yalkeonic acid, but may be released from the cement. The aluminium rel ease from auto-cured and light-cured glass ionomer cements during earl y water exposure was studied. The former cements released more alumini um than the latter. Scanning electron microscopy (SEM) showed extensiv e loss of polymer matrix for the cements with the highest aluminium re lease. Insufficient curing of light-cured cements also resulted in los s of matrix. It is suggested that the considerable release of aluminiu m from glass ionomer cements during early water exposure may explain t he reported lack of mineralization of predentin in the pulp beneath gl ass ionomer cements. This would correspond to the inhibiting effect of aluminium on bone mineralization.