objectives: the aim of this study was to compare the permeability of dentin after using diamond bur and er:yag laser. materials and methods: seventy-two recently extracted, intact, and restoration-free human permanent molars were used in this study. the samples were randomly divided into three groups of 24 each and class i cavities were prepared as follows. group 1: high speed diamond bur with ...

in this article we review the application and procedures involved in scanning electron microscope (sem) to observe biological and live tissues through using sem at high resolution. we discuss practical methods for optimizing tissue preservation to achieve the two principal goals of biological specimen preparation: (a) preserving biological structures as close to their living configuration as po...

objective: repair of an indirect restoration is usually preferred over its replacement. this study aimed to evaluate the effect of silane in different surface preparation techniques on the bond strength of direct to indirect composite resin.   methods: for this in vitro experimental study, 48 indirect composite cubes were fabricated, divided into 4 groups of 12 and subjected to the following pr...

purpose the aim of this study was to compare the levels of serum immunoglobulin (iga, igm, igg), testosterone and cortisol in semi-endurance elite runners during general preparation and competition phase of training. methods thirteen semi-endurance elite male runners with an average age of 18.92±1.7 years volunteered to take part in this study. the runners participated in the selected training ...

statement of the problem: porcelain laminate veneer is an esthetic restoration used as an alternative to full veneer crowns and requires minimal tooth preparation. in restoration with porcelain laminate veneers, both the longevity of the laminate and conservation of the sound tooth structure are imperative. purpose: the present study aimed to investigate the shear bond strength of porcelain lam...

As food legislation calls for methods of control, reliable analytical methods have to be available to make the enforcement of regulations possible. The reliability of analysis data can be improved through the use of methods that fulfil certain performance criteria (demonstrated in interlaboratory studies) and the application of analytical quality assurance (AQA) procedures is recommended, inclu...

The American Society for Gastrointestinal Endoscopy (ASGE) Technology Committee provides reviews of existing, new, or emerging endoscopic technologies that have an impact on the practice of GI endoscopy. Evidence-based methods are used with a MEDLINE literature search to identify pertinent clinical studies on the topic and a MAUDE (Food and Drug Administration Center for Devices and Radiologica...

A panorama of sample preparation methods has been composed from 481 references, with a highlight of some promising methods fast developed during recent years and a somewhat brief introduction on most of the well-developed methods. All the samples were commonly referred to molecular composition, being extendable to particles including cells but not to organs, tissues and larger bodies. Some crit...

Sample preparation. The structure of CoPOM and ZnPOM have been previously reported. The complexes used in this work have been synthesized using the procedure described for the analogous MnII compound but using Co(SO4) and Zn(SO4) instead of Mn(SO4). HiPCo SWNTs were purchased from Carbon Inc. and purified by the gas phase method. All the solutions were prepared using Millipore water. Functional...

PDLCs consist of liquid crystal droplets that are dispersed in a solid polymer matrix. The resulting material is a sort of "swiss cheese" polymer with liquid crystal droplets filling in the holes. These tiny droplets (a few microns across for practical applications) are responsible for the unique behavior of the material. By changing the orientation of the liquid crystal molecules with an elect...