SIGNIFICANCE This study did not identify clear advantages of using the first generation of ormocer-based fillings rather than conventional composites .
OBJECTIVES In-vitro experiments on  ormocers ( ORganically MOdified CERamics )  have provided controversial results .
Consequently , the objectives of this meta- analysis were to ( 1 ) compare clinical performances of first generation ormocers versus conventional composite restorations  , ( 2 ) explore the influence of various clinical factors and the impact of the quality of studies on published results .
Silorane, ormocer, methacrylate and compomer long-term staining susceptibility using ΔE and ΔE00 colour-difference formulas
The aim of this study was to evaluate the staining susceptibility of a silorane ( Filtek Silorane ) , an ormocer ( Ceram X Duo ) , a methacrylate ( Tetric EvoCeram ) and a compomer ( Dyract ) exposed on the long term to various staining agents by using ΔE and ΔE00 colour-difference formulas . Thirty-six disc-shaped specimens were made of each of the four chemically different material s , r and omly divided in six groups ( n = 6 ) and immersed in five staining solutions ( red wine , juice , coke , tea and coffee ) or stored dry ( control ) in an incubator at 37 ° C for 99 days . Spectrophotometric measurements by means of a spectrophotometer ( Spectroshade H and y Dental , MHT ) were repeated over a white ( L * = 92.6 , a * = −1.2 , b * = 2.9 ) and black ( L * = 1.6 , a * = 1.2 , b * = −1.0 ) background made of plasticized paper , in order to determine the colour changes according to ΔE , ΔE00 and translucency formulas . Statistical analysis was performed by means of factorial Anova , Fisher ’s LSD test ( post hoc ) and a Spearman rank correlation between ΔE and ΔE00 . When analysed over a white background , mean ΔE00 values were highly significantly different and varied from 0.8 ( Ceram X Duo/air ) to 20.9 ( Ceram X Duo/red wine ) . When analysed over a black background , mean ΔE00 values were highly significantly different and varied from 1.0 ( Ceram X Duo and Tetric/air ) to 25.2 ( Ceram X Duo/red wine ) . Differences in translucency varied from 0.3 ( Ceram X Duo/air ) to 21.1 ( Ceram X Duo/juice ) . The correlation between ΔE and ΔE00 over a white background was 0.9928 , while over a black background , it was 0.9886
SIGNIFICANCE This study did not identify clear advantages of using the first generation of ormocer-based fillings rather than conventional composites .
OBJECTIVES In-vitro experiments on  ormocers ( ORganically MOdified CERamics )  have provided controversial results .
Consequently , the objectives of this meta- analysis were to ( 1 ) compare clinical performances of first generation ormocers versus conventional composite restorations  , ( 2 ) explore the influence of various clinical factors and the impact of the quality of studies on published results .