Effect of preheating on polymerization shrinkage strain of BIS-GMA free and containing resin composite restorative materials (in vitro study)

Bulletin of the National Research Centre

Table 2 Effect of temperature on post-gel polymerization shrinkage strain of different groups

Post-gel polymerization shrinkage strain	Heating temperature
	T1		T2		T3		p value
	Mean	SD	Mean	SD	Mean	SD	p value
Viscalor (A1)	− 314.00	17.82	− 321.00	24.85	− 468.00	12.04	< 0.001*
Admira (A2)	− 635.00	54.77	− 569.00	51.16	− 667.00	80.51	0.082 ns
p value	< 0.001*		< 0.001*		0.001*