to evaluate the ultimate compressive strength of five composite resins after 1 hour, 24 hours, 7 days and 1 month. twenty four cylindrical 4 mm×8mm specimens of each commonly used composite resins in posterior region (nulite-f , z250 , p60, biscore, tetric ceram hb) were prepared. each group of composite resins were divided into four time groups of 1 h, 24 h, 7 days and 1 month. all of specimen...

The aim of this study was to determine the degradation resistance of three new formulations-silorane-, Ormocer- and dimer-acid-based materials-and compare them to the traditional dimethacrylate-based materials. One silorane- (Filtek P90, P90), one Ormocer- (Ceram-X, CX), one dimer-acid- (N'Durance, ND) and two dimethacrylate-based (Filtek P60, P60; Tetric Ceram, TC) materials were investigated....

The aim of this study was to observe the influence of two light polymerization units (LED or halogen light) on the degree of conversion (DC) of three dental composites with lighter shades and a different photoinitiator system. The top (T) and bottom (B) surfaces of 60 discs of composite resin (Filtek™ Supreme, Filtek™ Z250, Tetric™ Ceram Bleach) cured either by LED or by halogen lamp (HL) were ...

Introduction: The aim of the present study was to evaluate the effect of glass ceramic insert in the sandwich technique to reduce microleakage in class II composite resin restorations. Methods: Sixty sound human upper second premolars were selected and randomly divided into six groups (n=10). Class II boxonly cavities were prepared in distal aspects of each tooth with gingival margin located ap...

AIM The aim was to perform comparative analysis of bioactive, contemporary bulk-fill resin-based composites (RBCs) and conventional glass-ionomer materials for flexural strength (FS), diametral tensile strength (DTS), and Vickers hardness number (VHN) in the presence of thermocycling. MATERIALS AND METHODS Five restorative materials [Tetric N-Ceram Bulk Fill; smart dentin replacement (SDR) Fl...

Purpose: The aim of this study was to investigate the effect different aging methods on repair bond strength types composite resins. Materials and Methods: Thirty resin blocks (5mm×5mm×4mm) were built up with a nanohybrid universal bulk-fill according manufacturer’s instructions, using silicone matrix. Indirect obtained similar dimensions from prefabricated by microtome. All samples air abraded...

     To evaluate the ultimate compressive strength of five composite resins after 1 hour, 24 hours, 7 days and 1 month. Twenty four cylindric...

Post-operative hypersensitivity still occurs although the improvements in adhesive systems and their techniques, so current study was conducted to evaluate efficacy of two desensitizing systems. Materials methods: A total No. 48 patients were randomly divided into 3 groups (n=16); Gluma group, SAD control group. Class I cavity preparation self-etch bonding technique used by Universal system bef...

BACKGROUND: Dental caries is the most common disease of oral cavity, which can usually be treated by direct composite restoration.
 AIM: To assess quality marginal fit adhesive systems and photocomposites to hard tissues tooth.
 MATERIALS AND METHODS: A scanning electron microscopic study was conducted with 30 restorations on teeth previously removed for medical reasons using a 7th-ge...