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D Riis

Publications and source records attributed to D Riis.

3 recordsLinked to original sources

Advances and current research in ceramic restorative materials.

Ceramics are currently the most widely used material for veneering crowns and bridges. Newer applications, such as bonded inlays, onlays, and veneers, are steadily gaining in popularity. A new generation of metal-free, all-ceramic systems for crowns became available during the 1980s. More recently, other all-ceramic systems with improved mechanical properties affording a variety of uses have been introduced. Also, a computer-assisted design-computer-assisted manufacture method of fabricating ceramic inlays has become a routine treatment entity with favorable 5-year clinical data. Research is leading to a better understanding of conventional ceramic systems as well as providing information on laboratory manipulation and clinical methodology for optimal results.

Crowns↗

Histologic evaluation of electrosurgery with varying frequency and waveform.

This investigation was designed to determine the differences in tissue alteration produced by electrosurgical machines with different carrier frequencies and waveforms. Histologic analysis showed that: 1. The machine with full-wave rectification and the lowest frequency of operation (machine I, 1.7 MHz) produced significantly greater tissue alteration in the superficial tissue layers than the full-wave rectification machines with higher frequencies of operation. 2. The continuous-output waveform produced significantly less tissue alteration in the superficial tissue layers than the modulated type at the same frequency of operation. 3. Histologically, the experimental defect showed a band of coagulation necrosis approximately 50 mu wide along the margin of the incision. Tissue destruction decreased laterally and inferiorly from the surface of the defect. 4. The experimental defect was similar in shape to the physical form of the cutting electrode.

Animals↗