AIM The aim of the present study was to evaluate the effect of the use of composite fibers (glass fiber and polyethylene fiber) at the gingival third of mesio-occlusodistal (MOD) cavities on the fracture resistance of endodontically treated premolars. MATERIALS AND METHODS A total of 45 extracted premolars underwent endodontic treatment. MOD cavities, 2.5 ± 0.2 mm thick at the buccal and ling...

the effects of closely adapting a prefabricated fiber to the post space remain unknown. the purpose of this study was to quantify the microleakages of a custom adapted fiber-reinforced post, a prefabricated quartz fiber post and a cast post using nondestructive methods.sixty-five extracted human premolars were endodontically treated and randomly divided into three groups (n=15), which were rest...

In this study, six combinations of flax, hemp, and glass fiber were investigated for a hybrid reinforcement system in a polyurethane (PU) composite. The natural fibers were combined with glass fibers in a PU composite in order to achieve a better mechanical reinforcement in the composite material. The effect of fiber hybridization in PU composites was evaluated through physical and mechanical p...

The aim of this study was to deyelop a noyel hydroxyapatite (HA) coating method on zirconia using glass coating technique. A borosi)icate glass, the mixture of the glass ttnd HA (3e, 50, 70, and 90 mass%), and the 100% HA were coated on two kinds of zirconia discs and fired at 900-950'C. After the final coating, the surface of the sample was etched for 3 min in an acid-mixture of 3% HF and 5%HN...

The purpose of this study was to investigate the reinforcing effect of short E-glass fiber fillers oriented in different directions on composite resin under static and dynamic loading. Experimental short fiber-reinforced composite resin (FC) was prepared by mixing 22.5 wt% of short E-glass fibers, 22.5 wt% of resin, and 55 wt% of silane-treated silica fillers. Three groups of specimens (n=5) we...

1. Abstract Natural fibers are being increasingly used to substitute artificial glass and carbon fibers in polymer composites. It is important to know how the mechanical properties of these natural fiber composites compare with those of the traditional glass and carbon fiber composites. Glass and carbon fiber composites are currently being used in many applications that may not require such hig...

Yttria partially stabilized zirconia (YPSZ) ceramics are suitable for dental and medical use because of their high fracture toughness and chemical durability. The purpose of this study was to examine the bonding behavior of a dental YPSZ ceramic, Denzir. After being subjected to various surface treatments, Denzir specimens were bonded to each other using an adhesive resin composite, glass ionom...

This study was performed to evaluate the effect of a lithium-disilicate spray-liner application on both the bond strength between zirconia cores and heat-pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of all-ceramic zirconia crowns. A lithium-disilicate reinforced liner was applied on the surface of a zirconia core and lithium-disilicate glass-ceramic was veneered o...

conclusions: The restoration of root canal treated teeth – because of the significant loss of tooth structureis often achieved with post and core. However, posts may generate stresses, which lead to vertical root fracture and the loss of the tooth. Since post design, materials used and post space preparation has significant influence on vertical fracture prevalence, broad investigation is in pr...

Background: Silane coupling agents are used as a bonding agent between ceramics and resins in dentistry. The effectiveness of these agents is often enhanced by the addition of acid or by heat treatment. Objective: This study aimed to evaluate, the clinical characteristics, TBS (tensile bond strength) and water resistance of eight commercial ceramic primers (seven silane coupling agents and one ...