1015 Effect of mixing methods on the bonding strength of GIC

Friday, March 23, 2012: 3:30 p.m. - 4:45 p.m.
Presentation Type: Poster Session
R. AKATSUKA, S. FUKUSHIMA, and K. SASAKI, Prostehtic Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan

Objectives: The aim of this study was to evaluate the effect of the different mixing methods on tensile bond strength (TBS) of glass-ionomer-cement (GIC). This study evaluated TBS of GIC to bovine enamel (BE), bovine dentin (BD), and gold alloy (CASTWELL M.C. 12%GOLD:CW12 and CASTING GOLDM.C.TYPE III:CG3, GC) for prosthetic restoration.

Methods: The trial material FL-901 paste type GIC(GC) by hand-mix(FL-HM) and that by auto-mix(FL-AM) were evaluated. The latter were mixed by using the mixing tip. RelyX™ Luting Plus Cement(RXLP) paste type GIC(3M ESPE) in the clicker dispenser and RelyX™ Luting Cement(RXL) powder/liquid type GIC(3M ESPE), both were evaluated by hand-mix. All were mixed according to manufacturer's instructions. TBS test was carried out according to ISO/TS11405 (n=5). For the before thermocycled(TC0) specimens, TBS was measured (1mm/min) by an Autograph (SIMADZU) after 24hour at 37░C-100%RH. The other specimens were thermocycled (TC2000, 5/55░C) and followed by the measurement. The results were analyzed by three-way ANOVA and Turkey test.

Results: The mean values and S.D. were shown in the following table. There were no significant difference of TBS in the mixing methods and in among the different materials (p<0.01). However, there were significant difference in the factor of the substrate (p<0.01) and the thermocycle (p<0.05).

TBS:MPa

FL-HM(S.D.)

FL-HM(S.D.)

RXLP(S.D.)

RXL(S.D.)

TC0

TC2000

TC0

TC2000

TC0

TC2000

TC0

TC2000

BE

10.0(▒2.3)

8.2(▒2.3)

9.2(▒0.5)

10.2(▒2.4)

11.9(▒5.6)

12.7(▒3.1)

9.8(▒2.5)

8.9(▒1.2)

BD

7.2(▒1.4)

5.3(▒1.4)

7.0(▒0.8)

6.2(▒1.6)

7.9(▒1.4)

8.6(▒3.2)

8.4(▒2.3)

5.9(▒1.5)

CW12

11.2(▒2.7)

11.2(▒5.0)

9.2(▒2.9)

8.1(▒0.8)

7.9(▒2.0)

5.7(▒0.7)

8.0(▒1.4)

6.4(▒1.7)

CG3

11.4(▒2.0)

11.8(▒2.5)

10.0(▒2.6)

10.1(▒1.5)

8.7(▒1.2)

7.4(▒2.0)

12.1(▒2.3)

10.6(▒1.2)

Conclusions: In this study, there was no significant difference of TBS in the mixing methods. Therefore, it is thought that auto-mix system demonstrates bonding stability like hand-mixing in clinical.


Keywords: Bonding strength, Cements, Dental materials and Prostheses