Clinical success of class V composite resin restorations without mechanical retention.

The authors describe a study in which they placed 126 Class V composite resin restorations without mechanical retention, divided into three groups of 42, in 23 patients. They followed the performance of the restorations over a three-year period. For all three groups, restorations were placed using All-Bond 2 dental adhesive and Z100 composite resin; A.R.T. Bond and Brilliant Dentin composite; and Prisma Universal Bond 3 and Variglass VLC polyacid-modified composite resin. The authors evaluated retention as well as color stability, wear resistance, sensitivity, sulcular depth, loss of attachment, bleeding on probing and crevicular fluid flow. Based on their results, the authors propose that restoration of Class V lesions without using mechanical retention could be expected to succeed in seven of 10 restorations over a three-year period using these restorative systems.

Dental amalgam. The state of the art and science.

When you balance the benefits and liabilities of a modern dental amalgam, it is one of the materials that comes closet to being an ideal restorative. Its numerous clinical advantages have, in the past, made it a standard in dental care. The profession's and public's awareness of the issues surrounding the mercury content, coupled with the biased reporting of the controversy by less than responsible journalists, have served to impung the material. The dental profession has used the material successfully in its present form for almost 100 years. There are still valid questions about the material that require further scientific investigation. Investigators continue to make improvements in the alloy's strength and handling properties while limiting the mercury-release potential of the material. As we move into the twenty-first century, we are again told we will soon have a suitable replacement for dental amalgam. That is an often repeated promise for this multifunctional product. Time and sound research into the longevity and liabilities of all restorative materials as applied in the office of the general practitioner will tell us if amalgam is or is not going to disappear from the dental armamentarium in the near future.

An evaluation of the marginal leakage of spherical high-copper amalgam.

Three high-copper spherical amalgam alloys and one conventional spherical alloy were compared for microleakage by placing restorations in 60 human premolars. The evaluations were made at 1 week, 1 month, and 3 months after condensation. Almost all the experimental alloys leaked to some degree. When they were evaluated for gross leakage (Class 4) or moderate leakage (Classes 0, 1, 2, and 3), Tytin and Cupralloy leaked significantly less than the control material. This study indicates that the lack of a gamma-2 corrosion does not increase the microleakage of amalgam restorations when these products are used.

A method of transferring mandibular-movement data to computer storage.

A method was briefly described which photographed engraved blocks of mandibular-movement recordings and transferred the information into computer memory. A photographic platform was designed to allow uniform photographing of the engraved blocks. The photographed information was then projected onto graph paper where it was traced. The traced information, with the centric point labeled, was transferred into computer memory via a Computek 531 tablet. An RMS (root-mean-squared) deviation test was conducted to estimate the reliability of this technique. The maximum deviation (0.363 mm.) was found for z coordinate of the left-side recording. Labeling the centric point in computer memory is very important. This allows careful and detailed study of movements in the area where clinical evaluation is of utmost importance to the dentist. As more data are collected and evaluated, questions related to occlusion, such as tooth stability, effect on periodontal health, relationship to orthodontic success, and the like, may be clarified.