Adhesive Properties of A New Self-Adhesive Resin Cement

A new self-adhesive resin cement (SAC-A) has been developed. SAC-A is a dual-curing, fluoride-releasing luting cement for adhesive cementation composed of an adhesive phosphate monomer (MDP), dimethacrylate monomers, initiators, fillers and functionalized sodium fluoride.

Objectives: The purpose of this study was to compare share bond strength, water sorption and linear expansion of SAC-A with those of other commercially available cements (RelyX Unicem Aplicap/Clicker; 3M ESPE, Maxcem; Sybron-Kerr, and FujiCEM; GC).

Methods: Share bond strength to human enamel/dentin, gold alloy (Casting gold IV; GC), and zirconia (Cercon; Dentsply) was measured both after storage in 37˚C water for 24h and after subsequent thermocycling(TC3000). Each cement was bonded according to the manufacturer's instruction. Water sorption was measured according to ISO4049:2000.Linear expansion was evaluated by the changes in diameter of disc specimens after 4 weeks of water storage.

Results:                                                                                                     Mean(SD)

Cement		SAC-A	Unicem		Maxcem	FujiCEM
			Aplicap	Clicker
Shear bond strength (MPa)
Human enamel	24h	15.2(2.2)	10.7(5.3)	7.0(1.4)	7.9(6.2)	11.4(4.3)
	TC3000	18.9(3.9)	14.2(1.1)	9.4(5.5)	10.5(5.3)	2.0(1.1)
Human dentin	24h	10.2(4.9)	8.2(6.1)	7.1(1.7)	6.2(0.3)	1.2(0.7)
	TC3000	10.9(3.3)	10.6(4.6)	8.6(1.9)	3.3(0.9)	1.2(2.0)
Gold alloy	24h	22.1(6.9)	21.0(6.2)	20.8(8.1)	17.7(1.1)	5.1(1.3)
	TC3000	21.3(6.0)	15.8(4.7)	17.0(9.0)	14.7(5.5)	1.9(0.9)
Zirconia	24h	36.0(8.1)	26.1(1.7)	27.4(4.5)	26.4(8.0)	20.2(1.9)
	TC3000	33.4(1.9)	20.6(5.6)	26.4(5.7)	20.9(3.0)	14.2(2.5)
Water sorption (µg/mm3)		26.6(1.4)	30.9(0.4)	30.4(0.5)	74.7(2.2)	Not tested
Linear expansion (%)		0.23(0.02)	0.48(0.05)	0.41(0.07)	0.59(0.06)	1.34(0.08)

Share bond strength of SAC-A after 24h and TC3000 was higher than that of the other cements. SAC-A showed the least water sorption and linear expansion.

Conclusions: SAC-A showed the best bond strength and durability among the evaluated cements. This superior bond durability of SAC-A can be attributed to its low water absorbing property.