Tissue conditioners as functional impression materials.

J A McCarthy; J B Moser

doi:10.1111/j.1365-2842.1978.tb01254.x

Home/Archive/PubMed

PubMed · 280636

Tissue conditioners as functional impression materials.

J A McCarthy·J B Moser

View original source ↗Export metadata ↓

Abstract

Permanent deformation, strain in compression, flow, dimensional stability, reproduction of detail and gypsum compatibility of three commercial tissue conditioners (Coe-Comfort, FITT and Hydro-cast) and one polysulphide base Type I impression material (Coe-flex) were measured according to ADA Specification No. 19. Although the tissue conditioners generally exhibited higher deformations and lower gypsum compatibility than specified by ADA Specification No. 19, the materials can, in all probability, be considered adequate for the present. It would appear that the development of international standards for tissue conditioners and functional impression materials is badly needed.

Explore related subjects

Chemical Phenomena Chemistry, Physical Dental Impression Materials Elasticity Polymers Rheology Stress, Mechanical Sulfides Surface Properties Tissue Conditioning, Dental Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

J A McCarthy, J B Moser. 1978. Tissue conditioners as functional impression materials.. https://doi.org/10.1111/j.1365-2842.1978.tb01254.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1995

A thermal broadening analysis of absorption spectra of the D1/D2/cytochrome b-559 complex in terms of Gaussian decomposition sub-bands.

Absorption spectra of the isolated D1/D2/cytochrome b-559 complex have been measured in the temperature range 80-300 K. All spectra were analyzed in terms of a linear combination of Gaussian bands and the thermal broadening data interpreted in terms of a model in which the spectrum of each pigment site is broadened by (a) a homogeneous component due to linear electron-phonon coupling to a low-frequency protein vibration and (b) an inhomogeneous component associated with stochastic fluctuations at each pigment site. In order to obtain a numerically adequate description of the absorption spectra, a minimum number of five sub-bands is required. Further refinement of this sub-band description was achieved by taking into account published data from hole burning and absorption difference spectroscopy. In this way, both a six sub-band description and a seven sub-band description were generated. In arriving at the seven sub-band description, the original five sub-band wavelength positions were essentially unchanged. Thermal broadening analysis of the seven sub-band description yielded data which displayed the closest correspondence with the literature observations. The wavelength positions of the sub-bands were near 661, 667, 670, and 675 nm, with two bands near 680 and 684 nm. The two almost isoenergetic sub-bands near 680 nm, identified as P680 and pheophytin, have optical reorganization energies around 40 and 16 cm-1, respectively. All other sub-bands, identified as accessory pigments, have optical reorganization energies close to 16 cm-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Chemical Phenomena↗

PubMed1995

Interaction of anionic/nonionic surfactant mixtures with phosphatidylcholine liposomes.

The mechanisms governing the interaction of mixtures of sodium dodecyl sulfate (SDS) and nonylphenol oxyethylenated with 10 mol of ethylene oxide (NP(EO)10) with phosphatidylcholine liposomes were investigated. Permeability alterations were detected as a change in 5(6)-carboxyfluorescein (CF) released from the interior of vesicles and bilayer solubilization as a decrease in the static light scattered by liposome suspensions. Three parameters were described as the effective surfactant/lipid molar ratios (Re) at which the surfactant system (a) resulted in 50% of CF release (Re50%CF), (b) saturated the liposomes (ReSAT), and (c) led to a complete solubilization of these structures (ReSOL). From these parameters the corresponding surfactant partition coefficients (K50%CF, KSAT, and KSOL) were determined. Despite the fact that Re increased as the mole fraction of the SDS rose (XSDS), the K parameters showed maximum values at XSDS 0.6 and 0.2 for K50%CF and KSAT, respectively, the KSOL reaching the highest value in the absence of SDS XSDS = 0). Thus, the higher the surfactant contribution in surfactant/lipid system, the lower the XSDS at which the maximum bilayer/water partitioning of mixed surfactant systems added took place. The free surfactant concentrations SW were lower than the mixed surfactant CMCs at subsolubilizing level, whereas it remained similar to these values during saturation and solubilization of bilayers in all cases.

Chemical Phenomena↗

PubMed1995

Temperature measurements of shock-compressed liquid hydrogen: implications for the interior of Jupiter.

Shock temperatures of hydrogen up to 5200 kelvin were measured optically at pressures up to 83 gigapascals (830 kilobars). At highest pressures, the measured temperatures are substantially lower than predicted. These lower temperatures are caused by a continuous dissociative phase transition above 20 gigapascals. Because hydrogen is in thermal equilibrium in shock-compression experiments, the theory derived from the shock data can be applied to Jupiter. The planet's molecular envelope is cooler and has much less temperature variation than previously believed. The continuous dissociative phase transition suggests that there is no sharp boundary between Jupiter's molecular mantle and its metallic core. A possible convectively quiescent boundary layer might induce an additional layer in the molecular region, as has been predicted.

Chemical Phenomena↗