426 - The Effect of Light-Curing on GIC Flexural Strength

Purpose:

The light-curing of glass ionomer cements (GIC) may accelerate their setting time and benefit pediatric and special needs patients; however, it may also risk weakening the GIC. This study was to determine the effect of light-curing on the flexural strength (FS) of two GIC after 24 hours and 7 days.  

Methods:

Two GIC, Fuji Equia Forte (FE) and 3M Ketac Universal Aplicap (3M), were tested. The three-point bend FS bars of the materials (6 specimens/group) were fabricated by dispensing material into lightly lubricated metal molds. Specimens were either light-cured for 20 seconds or left self-cured, and then stored in water at 37°C until testing. FS was measured with an Instron machine after 24 hours and 7 days. FS between groups was compared using t-tests.

Results:

The FS of self-cured and light-cured FE were 19.82 ± 5.27 (mean ± standard deviation) MPa and 16.84 ± 2.01 MPa after 24 hours, and 22.89 ± 6.05 MPa and 21.22 ± 3.73 MPa after 7 days, respectively.  The FS of self-cured and light-cured 3M were 11.32 ± 2.51 MPa and 9.83 ± 1.08 MPa after 24 hours, and 12.58 ± 1.85 MPa and 12.76 ± 1.60 MPa after 7 days, respectively.  No significant differences in FS between self-curing and light-curing of FE or 3M were seen after 24 hours or 7 days.

Conclusion:

Light-curing may be used for command setting of some conventional GIC to accelerate clinical setting without compromising their FS.

Identify Supporting Agency and Grant Number: