Polymerization shrinkage : similar to or greater that that of non packable material solitaires highest value extending 3 %.
Radiopacity : all packable composites, except solitaire have radiopacity exceeding 2 mm of aluminimum. Solitaire may be due to low volume of radiopaque filler and chemical composition of the fillers.
Inorganic filler content : two distinct and rela;tively narrow distributions volume.
Low group 48 % (approximately) Pyramid enamel, solitaire High Group 60 % alert, Pyramid Dentin, surefill
The major advantage/benefit of these new composites is their thicker consistency, which may be deemed helpful in achieving tight interproximal contacts.
COMPOMERS (Polyacid – Modified Resin Composites): Compomer is resin-ionomer hybrid restorative material marketed as multipurpose material, as resin that may release fluoride but have only limited glass ionomer properties. (It contains the major ingredients of both composites (resin component) and glass ionomer cements (polyalkenoate acid and glass fillers component) except for water. They have a limited dual setting mechanism, dominant setting reaction is the resinous photopolymerisation and no acid base reaction can occur until the material absorbs water.