STATEMENT OF PROBLEM Streptococcus mutans can adhere at restored tooth margins to cause recurrent caries. Limited information about surface quality and bacterial adherence is available for lithium disilicate ceramic materials. PURPOSE The purpose of this in vitro study was to investigate how bacterial adherence is influenced by commercially available preparations of lithium disilicate ceramic...

The present study was conducted to determine the effect on the distribution of stress with the use of short-post cores and over restorations composed of different materials. The restorative materials used were namely two different composite resin materials (Valux Plus and Tetric Flow), a polyacid-modified resin material (Dyract AP), and a woven polyethylene fiber combination (Ribbond Fiber + Bo...

The contraction stress generated during the photopolymerization of resin dental composites is the major disadvantage. The water sorption in the oral environment should counteract the contraction stress. The purpose was to evaluate the influence of the water sorption of composite materials on polymerization shrinkage stress generated at the restoration-tooth interface. The following materials we...

This paper studies the semantics of discrete-event systems as a concurrent model of computation. The classical approach, which is based on metric spaces, does not handle well multiplicities of simultaneous events, yet such simultaneity is a common property of discrete-event models and modeling languages. (Consider, for example, delta time in VHDL.) In this paper, we develop a semantics using an...

Purpose: The purpose of the current study was to examine the effect of accelerated aging on color stability of the In-Ceram and Cergogold ceramic materials. Materials and Methods: Ceramic samples with 1.0 mm in diameter and 1.5 mm in thickness were prepared in three commonly used shades. CIE Lab readings were recorded with a spectrophotometer prior to experiments and after 100-hour accelerated ...

OBJECTIVE The objective of the present study is to evaluate and compare the flexural strength, dynamic elastic moduli and true hardness (H(o)) values of commercial Vita In-Ceram alumina core and Vita In-Ceram matrix glass with the standard aluminous porcelain (Hi-Ceram and Vitadur), Vitadur N and Dicor glass and glass-ceramic. METHODS The flexural strength was evaluated (n=5) using 3-point lo...

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 study evaluated the fracture resistance of endodontically treated teeth restored with fiber reinforced composite posts, using three resin composite core build-up materials, (Clearfil Photo Core (CPC), MultiCore Flow (MCF), and LuxaCore Z-Dual (LCZ)), and a nanohybrid composite, (Tetric N-Ceram (TNC)). Material and Methods Forty endodontically treated lower first premolars were ...

AIM The aim of this in vitro study was to investigate the cervical microleakage and internal voids of nanocomposites comparing them with a hybrid composite in Class II restorations with the margins located coronal and apical to the cementoenamel junction (CEJ). METHODS AND MATERIALS Standardized MOD cavities (one cervical margin located in dentin, one in enamel) were prepared in 40 extracted ...