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 .
Eight-year randomized clinical evaluation of Class II nanohybrid resin composite restorations bonded with a one-step self-etch or a two-step etch-and-rinse adhesive
Objectives The aim of this study is to observe the durability of Class II nanohybrid resin composite restorations  , placed with two different adhesive systems , in an 8-year follow-up . Methods Seventy-eight participants received at r and om at least two Class II restorations of the ormocer-based nanohybrid resin composite ( Ceram X ) bonded with either a one-step self-etch adhesive ( Xeno III ) or a control two-step etch- and -rinse adhesive ( Excite ) . The 165 restorations were evaluated using slightly modified United States Public Health Services ( USPHS ) criteria at baseline and then yearly during 8 years . Results One hundred and fifty-eight restorations were evaluated after 8 years . Three participants with five restorations ( three Xeno III , two Excite ) were registered as dropouts . Twenty-one failed restorations ( 13.3 % ) were observed during the follow-up . Twelve in the one-step self-etch adhesive group ( 13.5 % ) and nine in the two-step etch- and -rinse group ( 13.0 % ) . This result ed in nonsignificant different annual failure rates of 1.69 and 1.63 % , respectively . Fracture of restoration was the main reason for failure . Conclusion Good clinical performance was shown during the 8-year evaluation and no significant difference in overall clinical performance between the two adhesives . Fracture was the main reason for failure . Clinical relevance The one-step self-etch adhesive showed a good long-term clinical effectiveness in combination with the nanohybrid resin composite in Class II restorations
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 .