Clinical behavior of silver-palladium alloy castings: a five-year comparative clinical study

Crowns and extra-coronal restorations: materials selection

Materials selection is the second in the series on crowns and other extra-coronal restorations. Some of us are less than inspired by dental materials science. Nevertheless, many of the things that concern us clinically with crowns and their alternatives are based on material properties. We worry about the strength of the restoration, how well it fits and its aesthetics. We also worry about wear, occlusal control and biocompatibility. Not least of our concerns are dental laboratory charges, which inevitably have to be passed on to the patient.

Automatic enumeration of adherent streptococci or actinomyces on dental alloy by fluorescence image analysis

The aim of the present study was to develop an automated image analysis method to quantify adherence of Streptococcus sanguinis or Actinomyces viscosus on surfaces of a currently used dental alloy. Counting such bacterial strains was difficult because of their arrangement, thus S. sanguinis being a coccus arranged in chains or pairs, and A. viscosus a long complexly arranged polymorph rod. Direct counting of fluorescently stained adherent bacteria was done visually and with image analysis methods. To differentiate these two morphotypes, two programs were developed: (i) for streptococci, thresholding and selection of the object maxima, and (ii) for actinomyces, two step thresholding and processing of the characteristic points of the object skeletons. The triplicate enumerations for each bacterial strain were not significantly different (p > 0.005) and correlations between visual counting and automated counting were significant (r = 0.91 for S. sanguinis and r = 0.99 for A. viscosus, p <00.0001). These rapid and reproducible methods, allowed us to count either cocci or rods, adherent on an inert substratum, in high density conditions.

Report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The committee screened several hundred articles, citing 518 published papers. Some are present quality in research, others provide clinical interest, and some are identified as misleading. New techniques in pulp physiology and pathology are reported. Laser use and techniques in prevention, restorative dentistry, and materials use are reported. Epidemiology of selected diseases and the results of various formulations for treatment are cited. Diagnosis of craniomandibular dysfunction is well represented as well as references to literature reviews and other sophisticated scientific investigation. Research on adhesives is presented in respect to bonding agents for dentin and enamel. Several clinical studies are included, along with customary laboratory reports on several materials.