transparent glasses in a system of li2o-mgo-sio2-al2o3-fchemical constituents were prepared by melt quenching method. in the fabrication of nanocrystal glass-ceramics, controlled nucleation and subsequent crystal growth were necessary to avoid loss of transparency. it was therefore important to understand thermal properties and crystallization kinetics of the glass ceramics. the crystallization...

objective: in all ceramic fixed partial dentures the connector area is a common fracture location. the survival time of three-unit fixed partial dentures may be improved by altering the connector design in regions of maximum tension. the purpose of this study was to determine the effect of buccolingual increase of the connector width on the stress distribution in posterior fixed partial denture...

PURPOSE The purposes of this study were to evaluate the staining resistance of CAD/CAM resin-ceramics polished with different techniques and to determine the effectiveness of the polishing techniques on resin-ceramics, comparing it with that of a glazed glass-ceramic. MATERIALS AND METHODS Four different CAD/CAM ceramics (feldspathic ceramic: C-CEREC Blocs, (SIRONA) and three resin-ceramics: ...

abstract   statement of problem: fracture of veneering porcelain has been described as the most frequent reason for the failure of zirconia-based fixed restorations. objectives: the purpose of this study was to evaluate and compare the shear bond strength of a zirconium oxide core material to three commercial veneering ceramics. materials and methods: three types of veneering ceramics were sele...

INTRODUCTION: In orthopedic surgery, bone grafting has been performed to treat diseases and injuries, such as bone tumor and bone fracture. In general, bone implantation is classified into three types: i) auto-grafting, ii) allografting and iii) artificial-bone grafting. Among these bone implantations, auto-grafting is well-known as a common practice and is harvested from the patient. However, ...

Background and Aim: Chairside computer-aided design/computer-aided manufacturing (CAD/CAM) systems have become considerably more accurate, reliable, efficient, fast, and prevalent since 1985 when CEREC was introduced. The inceptive restorative material option for chairside CAD/CAM restorations was limited to ceramic blocks. Today, restorative material options have been multiplied and include me...

titanium and its alloy are known as important load-bearing biomaterials. the major drawbacks of these metals are fibrous formation and low corrosion rate after implantation. the surface modification of biomedical implants through various methods such as plasma spray improves their osseointegration and clinical lifetime. different materials have been already used as coatings on biomedical implan...

nano-sized batio3 powders with particular nb concentrations were prepared by rotary- hydrothermal (rh) method. hydrothermal method was used at 180 °c for 5 hours with new ti pressure and the teflon vessel was rotated at a speed of 160 rpm during the hydrothermal reaction. new hydrothermal method was used instead of previous solid state reaction for the system batio3±nb2o3 in high temperature to...

Significant progress has been achieved in ceramics since the late 1990s1-4). In particular, new technological innovations such as heat-pressed5,6), injection-molded7), slip-cast8), and glass-infiltrated ceramics9-11) have widened the use of ceramics in prosthetic and operative dentistry. However, properties such as brittleness limit their use in applications such as fixed partial dentures. Sinc...

bioactive materials including glass and glass-ceramics are nowadays used as medical implants for orthopedic applications. in this study several samples of glass-ceramics have been prepared using both heat treatment and sol-gel processes. the structure and bioactivity of these samples based on their interaction with simulated body fluid (sbf) have been determined. in-vitor, using the raman spect...