background: restoration of anterior primary teeth with severe caries lesion is a big challenge. the aim of this study was to compare the fracture resistance of three types of post, including composite resin, customized quartz fi ber and prefabricated glass fi ber in restoration of severely damaged primary anterior teeth. materials and methods: sixty extracted human primary maxillary incisors we...

mechanical properties of non-split pistachio nuts are among the lada required for the design of equipment needed for processing of the nut. unsplit pistachio nut samples were uniaxially loaded to determine the nut’s needed splitting force and energy, as well as poisson’s ratio and young’s modulus of elasticity. the tests were carried out at four moisture contents (5, 10, 15 and 20% wb), under f...

  Objective: Despite the advantages of esthetic posts, lack of studies on their fracture resistance has limited their clinical use. This study aimed to compare the effect of two types of esthetic posts namely zirconia and zirconia enriched glass fiber composite posts on fracture resistance of endodontically treated teeth against compressive forces.   Methods: This in vitro study was conducted o...

Crack deflection and the subsequent growth of delamination cracks can be a potent source of energy dissipation during the fracture of layered ceramics. In this study, multilayered ceramics that consist of silicon nitride (Si3N4) layers separated by boron nitride/silicon nitride (BN/Si3N4) interphases have been manufactured and tested. Flexural tests reveal that the crack path is dependent on th...

AIM The aim of this study was to investigate the fracture resistance of two types of ceramic crowns cemented with two different cements. METHODS AND MATERIALS Forty premolar crowns were fabricated using lithium-disilicate (IPS Empress-2) and glass-infiltrated aluminium-oxide (In-Ceram) ceramic systems. The crowns were divided into four groups (n=10) with Group 1 (IPS Empress-2) and Group 2 (I...

introduction: this in vitro study evaluated the influence of composite thickness (with or without fiber reinforcement) on fracture resistance of direct restorations in endodontically treated teeth. methods and materials: fifty-six intact human premolars were chosen and randomly divided into four groups ( n =14). after preparation of a mesio-occluso-distal (mod) cavities and cusp reduction, the ...

The objective of the paper is to study the effect of cyclic loading on the fracture resistance of the SA 333 Gr.6 carbon steel material of the primary heat transport (PHT) system piping of Indian pressurized heavy water reactors (PHWR). Tests have been carried out on compact tension specimens machined from the pipe used in the PHT system. The effect of load ratio, incremental plastic displaceme...

BACKGROUND Combined amalgam-composite restorations have been used through many years to benefit from the advantages of both dental amalgam and composite resin. Two variations have been mentioned for this technique, this study investigated the fracture resistance of maxillary premolar teeth with extended mesio-occluso-distal (MOD) cavities, restored with the two variations of combined amalgam-co...

Background and aims. It is important to evaluate the effects of endodontic materials on tooth structures to avoid endodontic treatment failure. The aim of the present study was to investigate the effect of mineral trioxide aggregates (MTA) and Portland cement (PC) on fracture resistance of dentin. Materials and methods. Thirty-six freshly extracted human single-rooted premolar teeth were select...