The aim of this study was to evaluate the influence of thermal stress on the marginal integrity of restorative materials with different adhesive and thermal properties. Three hundred and sixty Class V cavities were prepared in buccal and lingual surfaces of 180 bovine incisors. Cervical and incisal walls were located in dentin and enamel, respectively. Specimens were restored with resin composi...

Retentive properties of three dental cements were tested using stainless steel crowns Fitted to extracted third molar teeth. No significant difference was Found between the overall mean retentive Forces of the polycarboxylate cement and the two glass ionomer cements. Mechanical retention of the crowns was not a Factor in the overall retentive value. Few studies have investigated the retention o...

In this paper, considering an adhesively bonded composite single-lap joint, a novel approach is presented to predict the peel and shear stress distributions of the adhesive layer for an ASTM standard test sample. In current method, the equilibrium equations are derived using the energy method and based on the Timoshenko’s beam theory. Two solution procedures then are discussed, one of which rep...

BACKGROUND The purpose of this study was to evaluate the effect of dehydration of resin-modified glass ionomer powder/liquid system, resin-modified glass ionomer paste/paste luting cements in three different quantities and to compare them with a conventional glass ionomer luting cement using confocal laser scanning microscope. MATERIALS AND METHODS A conventional glass ionomer (Group I), a re...

This study visually compared the radiopacity of seven restorative materials (3 resin-modified glass-ionomer cements, 3 polyacid-modified composite resins, and 1 conventional glass-ionomer cement) to a sound tooth structure sample, and an aluminium stepwedge. All hybrid materials were more radiopaque, except for one resin-modified glass-ionomer cement, than both the tooth structure and conventio...

Context. An in vitro study carried out to evaluate and compare the effect of Cola drink on surface roughness of esthetic restorative materials. Purpose. To compare the effect of different immersion regimes in a Cola drink on surface roughness of esthetic restorative materials. Method. Two hundred samples were grouped into 4 equal groups of 50 samples each: Group I: conventional glass ionomer, G...

 This study aimed to investigate the impact of N-vinylcaprolactam (NVC) and Nano-sized yttria-stabilized zirconia (YSZ), separately and simultaneously, on the mechanical properties of the commercial glass ionomer cements (GICs). Methods: The NVC is able to ameliorate the mechanical and surface properties of glass ionomers; however, its effect hasn’t been investigated in conjunc...

The specific adsorption of ionomer sulfonate groups on Pt-based catalysts in membrane electrode assemblies (MEAs) has severely restricted Pt catalytic activity, utilization, proton conductivity and mass transport. Here we report a blocking strategy using cyclohexanol to mitigate the detrimental impacts Nafion ionomer. Cyclohexanol with chair or boat conformation blocked path onto surface via co...

PURPOSE The aim of this study was to evaluate and compare the retention strength of three cements commonly used in implant-supported prostheses before and after compressive cyclic loading. MATERIALS AND METHODS The working model consisted of five solid abutments, 7 mm in height and with a 6-degree taper, screw retained to five implant analogs secured in a rectangular block of self-curing acry...