The solubility of resin luting cement remains unknown although the use
of resin luting cement for routine cementation of restorations has in
creased. The purpose of this in-vitro study was to compare the solubil
ities of three resin cements currently in clinical use with three bran
ds of conventional luting agents. The three resin luting cements, All-
Bond C&B(R) (AB, Bisco) Panavia 21(R) (P21, Kuraray), and Super-Bond C
&B(R) (SB, Sun-Medical), and the three conventional luting agents, Eli
te Cement 100(R) (EC, zinc phosphate cement, GC), MY-Bond Carbo-plus C
ement(R) (HCP, polycarboxylate cement, Shofu), and Fuji I(R) (FI, glas
s-ionomer cement, GC) were used in this study. A modification of the A
DA specification test was adopted to evaluate the solubilities of luti
ng cements. The two types of media (distilled water and pH 4.0 lactic
acid solution) in which specimens were stored for 30 days were prepare
d. The four luting cements, EC, Fl, AB, and P21, were more soluble in
lactic acid solution than in distilled water. Resin luting cements wer
e markedly less soluble than conventional luting agents when placed in
fresh lactic acid solution (0.001 mol/L) at pH 4.0 every 24 h over a
30-day period. The solubility rates of luting cements could be fitted
to mathematical expressions which indicated that the solubilities incr
eased linearly or logarithmically with immersion period. Fixed prostho
dontic restorations cemented with resin luting cement may be capable o
f withstanding long-term clinical use compared with conventional lutin
g agents.