Showing papers in "Dental Materials in 1986"

TL;DR: It is important for future clinical wear studies to resolve the question of the nature of the wear rate curve in posterior composites, if accurate prediction of long term performance is to be achieved.

TL;DR: The use of Weibull analysis enables fracture probability to be calculated as a function of applied stress and may be more applicable to the evaluation of biomaterials and devices than the more commonly used normal distribution.

TL;DR: Differences in K IC were attributed to differences in the nature of crack-microstructure interaction occurring in the two types of porcelain.

TL;DR: For one of the 3 brands, the Depth of cure for the darkest shade was equivalent to that of the lightest shade, suggesting that depth of cure of light-activated composite resins may be less dependent upon shade than upon translucency.

TL;DR: A quantitative method for measuring the wear of posterior composite restorations has been developed using the comparison of die stone casts of restored teeth to a set of calibrated standards as a means of evaluating the wear.

TL;DR: The modified DTA and technique are suitable for the measurement of temperature rises together with corresponding times, however, whilst it is possible to obtain the heat of reaction for the composite the dominance of heat from the light source reduces the accuracy of this measurement and an alternative approach should be considered for heats of reaction.

TL;DR: The thermal expansion of this frit was modelled as a weighted average of the leucite expansion as measured by hot-state x-ray diffraction and the expansion of the glass matrix calculated from its composition, finding close agreement between the predicted and measured expansion.

TL;DR: Using the techniques of following (re-measuring) microhardness indentations, surface roughness profiling and SEM before and after the in vivo experiment, one can conclude that all 3 systems showed material losses (surface degradation).

TL;DR: Simulated occlusal wear studies in an artificial mouth involving enamel occluding on porcelain demonstrated a high coefficient of wear for dental porcelains; in agreement with other workers, an abrasive wear process is postulated.

TL;DR: Fracture stress and flexural modulus were higher for the reinforced than for the unreinforced poly(methyl methacrylate) material, and Absorption of water decreased the flexural properties of the materials.

TL;DR: The results of this study indicate that the radiopaque composite P-30, compared to amalgam, has a degree of radiopacity which increases the detection rate of caries and defects adjacent to the restorations.

TL;DR: Tensile and shear bond strengths between restorative resin and flat human dentin surfaces were determined 15 min after polymerization of various resin systems in combination with 5 dentin bonding agents, indicating that strength values do not adequately delineate the effectiveness of dentinonding agents when used in cylindrical cavities.

TL;DR: Water and thermal cycling affected the materials differently depending on the properties of the filler particles, and an increase in surface degradation of a glass filled composite was attributed to the formation of microcracks or failure of filler/matrix bonds.

TL;DR: It is suggested that variations in temperature in the clinical range may reduce the fracture strength gained with bonded posterior composite resins, and polymerization shrinkage may produce clinically significant microleakage even before thermal cycling of the teeth.

TL;DR: The addition of silver to a glass ionomer cement reduced the fluoride release and the bond strength to dentin and Ketac-Silver only released significantly more F (μg F) during the first 7 days than KetAC-Silver.

TL;DR: The repaired microfilled composites had higher interfacial strengths, as a percentage of cohesive strength, than the macrofilled materials, and the dentin bonding agent, Scotchbond, gave the highest repair strengths.

TL;DR: The longitudinal displacement amplitude of the probe tip is the only means whereby the results of clinical trials using different probe designs and/or different instruments can be compared in a meaningful manner of the acoustic power output from the ultrasonic scaler.

TL;DR: The tensile bond strengths of 4 dentin bonding agents to dentin were determined by a test method developed by Kemper and Kilian (1976) and the data were analyzed by a one-way analysis of variance and by Duncan's multiple range test at the 5% level of significance.

TL;DR: A review of wetting, spreading and reactions of sodium discilicate glass on metals is presented and all of the reactions have an effect in some way on the bonding of glass to metal.

TL;DR: Phosphoric acid and pyruvic acid etching of polished enamel surfaces produced well-defined etching patterns and produced significantly greater bond strengths than citric acid.

TL;DR: Two standardized V-shaped cavities were prepared at the cementoenamel junction of buccal and lingual surfaces of each of 45 extracted premolars, and significantly more leakage was found in gingival (dentin or cementum) walls than in occlusal (enamel) walls.

TL;DR: Ful-Fil composite resin meets the current ADA Council on Dental Materials specifications for provisional acceptance in adult posterior teeth, and its ratings for color matching, interfacial staining, secondary caries, and marginal adaptation remained good after three years.

TL;DR: Evaluated composite resins placed in Class I and Class II preparations suggest that loss of anatomic form may be related to the size and composition of the filler particles in the resin restorative materials.

TL;DR: No statistically significant correlations were observed between the retentive capacity of the various cements and the size of the occlusal surface of the preparations, which may indicate a limited role for adhesion in the question of retentives capacity of luting cements.

TL;DR: There was no microscopic evidence to show that instrumentation or tapping produced microflaws in the dentin, and K and R systems displayed the greatest strength due to close approximation of post and root due to tapping.

TL;DR: Large variations in the bond strength values were observed for all adhesives, and Dentin-Adhesit had the highest values.

TL;DR: Microleakage of Class V amalgam restorations was studied, using 3 different types of alloy and varying numbers of application of cavity varnish, showing no statistical difference irrespective of the number ofvarnish applications.

TL;DR: The removable partial dentures made during one semester in the Department of Prosthetic Dentistry, University of Helsinki, were studied with regard to the accuracy of the fit of the metal palatal plate against the palate of the master cast and the mouth.