The meta- analysis of the data in the included studies demonstrated that only one variable ( marginal adaptation after 12 months ) showed statistically significant outcomes , in which methacrylates-based composites presented significantly better results than resin composites containing modified monomers .
The good level of the scientific evidence as well as the overall low risk of bias of the included studies indicate that composites with silorane , ormocer or bulk-fill type modified monomers have a clinical performance similar to conventional resin composites
Polymerization shrinkage of resin composite can compromise the longevity of restorations .
To minimize this problem , the monomeric composition of composites have been modified .
The objective of this study was to conduct a meta- analysis to assess the clinical behavior of restorations performed with low polymerization shrinkage resin composite  in comparison with traditional methacrylates-based resin composite .
Shrinkage assessment of low shrinkage composites using micro-computed tomography.
OBJECTIVES The aim of this study was to quantify the polymerization volumetric shrinkage of one regular and two low shrinkage bulk fill composites in class I cavities with or without an adhesive layer , using three-dimensional ( 3D ) micro-computed tomography ( μCT ) . METHODS Class I cavity preparations ( 2.5 mm depth × 4 mm length × 4 mm wide ) were st and ardized in 36 extracted human third molars , which were r and omly divided in six groups ( n = 6 each ) as follows : Group VIT ( regular composite without bonding agent ) ; Group SDR ( low shrinkage flowable composite without bonding agent ) ; Group TET ( low shrinkage composite without bonding agent ) ; Group VIT/P ( regular composite with bonding agent ) ; Group SDR/X ( low shrinkage flowable composite with bonding agent ) ; TET/T ( low shrinkage composite with bonding agent ) . Each tooth was scanned via µCT at cavity preparation , immediately after cavity filling , and after light-curing . Acquired μCT data were imported into Amira software for analysis and volume values evaluated between steps from cavity preparation until light-curing . RESULTS Both low shrinkage composites showed a significantly less volumetric shrinkage than VIT . The use of dental adhesive significantly decreased the average volumetric contraction similarly for the three composites , by about 20 % . CONCLUSION Both low shrinkage composites showed less volumetric polymerization contraction than the regular composite . The use of dental adhesive decreased the total volumetric shrinkage for all evaluated composites
The meta- analysis of the data in the included studies demonstrated that only one variable ( marginal adaptation after 12 months ) showed statistically significant outcomes , in which methacrylates-based composites presented significantly better results than resin composites containing modified monomers .
The good level of the scientific evidence as well as the overall low risk of bias of the included studies indicate that composites with silorane , ormocer or bulk-fill type modified monomers have a clinical performance similar to conventional resin composites
Polymerization shrinkage of resin composite can compromise the longevity of restorations .
To minimize this problem , the monomeric composition of composites have been modified .
The objective of this study was to conduct a meta- analysis to assess the clinical behavior of restorations performed with low polymerization shrinkage resin composite  in comparison with traditional methacrylates-based resin composite .