objective: various techniques of composite placement have been used to decrease microleakage around the composite restorations. due to controversial results, the present study was conducted to investigate the effect of different placement techniques on microleakage in class v composite restorations. materials and methods: sixty class v cavities were prepared on the buccal and lingual surfaces o...

Bisphenol A or BPA-based epoxy resins are widely used in the manufacture of commercial products, including dental resins, polycarbonate plastics, and the inner coating of food cans. BPA is a precursor to the resin monomer Bis-GMA. During the manufacturing process of Bis-GMA dental sealants, Bisphenol A (BPA) might be present as an impurity or as a degradation product of Bis-DMA through esterase...

objective: the purpose of the present study was to assess the microleakage of composite restorations with and without a cervical amalgam base and to compare the results of dif-ferent composites and bonding agents. materials and methods: one hundred and twenty mesio-occlusal (mo) and disto-occlusal (do) class ii cavities were prepared on sixty extracted permanent premolar teeth. the teeth were r...

objectives: this study aimed to determine the effect of surface treatments such as tooth reduction and extending the etching time on microtensile bond strength (µtbs) of composite resin to normal and fluorotic enamel after microabrasion. materials and methods: fifty non-carious anterior teeth were classified into two groups of normal and fluorotic (n=25) using thylstrup and fejerskov index (tfi...

Dental modeling resins have been developed for use in areas where highly precise resin structures are needed. The manufacturers claim that these polymethyl methacrylate/methyl methacrylate (PMMA/MMA) resins show little or no shrinkage after polymerization. This study examined the polymerization shrinkage of five dental modeling resins as well as one temporary PMMA/MMA resin (control). The morph...

objectives: microleakage is a major cause of failure of dental restorations and results in development of secondary caries, tooth hypersensitivity and pulp pathosis. this study aimed to compare the microleakage of class ii cavities filled with two types of composite resins and a compomer and subjected to thermocycling. methods: in this in vitro experimental study, class ii cavities with a gingi...

objectives: microleakage is the main concern in composite restorations. this study aimed to compare the microleakage of two bulk-fill and one conventional composite at two different time points. methods: class ii cavities were prepared in 60 premolar teeth and divided into six groups of 20. groups 1 and 4 were incrementally filled with grandio composite. groups 2 and 5 were filled with x-tra fi...

objective: this experimental in vitro study compared marginal adaptation of indirect composite, glass-ceramic inlays and direct composite. materials and methods: seventy-five recently extracted human molars were randomly divided into three groups (n=25) and mesio-occluso-distal cavities with the same dimensions were prepared in the teeth. indirect composite and glass-ceramic inlays were fabrica...

The gap between a metal crown and an abutment tooth often leads to troubles such as secondary caries, pulpitis, periodontitis and so on. We expected that newly developed adhesive resins which adhere both dental alloy and tooth structure can minimize such troubles if they were used as setting materials of prosthetics. In this study, the degree of marginal leakage of adhesive resins was compared ...

background and aims: new dentin bonding agents and techniques have been developed to reduce microleakage and create higher bond strength. this in-vitro study compared the microleakage of three resin-based adhesives versus a gic-based adhesive on class v composite restorations.  materials and methods: class v cavities were prepared on the buccal surfaces of 72 sound premolars, randomly assigned ...