Microleakage and penetration capability of various pit and fissure sealants upon different sealant application techniques.

Background: Sealant application that yields superior marginal adaptation and deeper fissure penetration potentially improves success in preventive and restorative dentistry. This study evaluated the amount of in-vitro microleakage and penetration capabilities of different pit-fissure sealants as the effect of different application techniques.

Material And Methods: 160 freshly extracted human sound premolars, assigned as suitable for sealant application, selected and allocated randomly into 8 groups (n=20 teeth/group) and applied with different sealants including Embrace-Wetbond® (E), UltraSeal XT® (U), Clinpro™ (CL), Helioseal® (H), using either conventional (C) or induced application (I).

Cyclic compression and decompression of a lipid bilayer.

In this study, we measure transient thicknesses of a lipid bilayer during electrostatic compression and decompression and deduce non-equilibrium molecular interactions of the surfactants' tails within the layer. The bilayer under investigation (sorbitan monooleate) is single-tailed and self-assembles between a water drop and hafnium oxide in dodecane. We detect minute changes in bilayer thickness (∼0.

Silk fibroin solution properties related to assembly and structure.

The impact of physiological factors on silk fibroin solution properties was studied. Specifically, the impact of fibroin concentration, protein purity, cation type and concentration, and pH on aqueous solution viscosity, shear behavior, and surface tension were assessed in the context of silk protein assembly. The results demonstrate that in vitro results could be correlated to in vivo processing events during silk spinning.

Irreversible electrowetting on thin fluoropolymer films.

A study was conducted to investigate electrowetting reversibility associated with repeated voltage actuations for an aqueous droplet situated on a silicon dioxide insulator coated with an amorphous fluoropolymer film ranging in thickness from 20 to 80 nm. The experimental results indicate that irreversible trapped charge may occur at the aqueous-solid interface, giving rise to contact angle relaxation. The accumulation of trapped charge was found to be related to the applied electric field intensity and the breakdown strength of the fluoropolymer.

Low voltage electrowetting using thin fluoroploymer films.

This paper investigates the nonideal electrowetting behavior of thin fluoroploymer films. Results are presented for a three phase system consisting of: (1) an aqueous water droplet containing sodium dodecyl sulfate (SDS), (2) phosphorous-doped silicon topped with SiO2 and an amorphous fluoroploymer (aFP) insulating top layer on which the droplet is situated, and (3) a dodecane oil that surrounds the droplet. The presented measurements indicate that the electrowetting equation is valid down to a 6 nm thick aFP film on a 11 nm thick SiO2.

An effective method for spreading flowable composites in resin-based restorations.

Unlabelled: Cavity lining with flowable composites has been suggested for better marginal adaptation and a reduction in interfacial stress and post-operative sensitivity. The following in vitro study compares the spreading of flowable composite that lines the inner wall of a test cavity using an explorer and a specially designed smooth, oscillating, off-center rotating bur spun at 300 to 600 rpm. Two commercial flowable materials were used in this study.