![]() ![]() Recycling sandblasters are also available with integrated (adjustable) nozzles, which can also be used for simultaneously sandblasting several similar frameworks (e.g. CoCr castings) automatically in a slowly rotating blasting basket. Combination sandblasters incorporate the two functions. Sandblasters are equipped with reservoirs ( abrasive tanks) for one or more different abrasives (different grit sizes). Modern units often have a modular design and can simply be extended with other abrasive tanks as required for additional applications. Color-coding is used to facilitate identification and assignment of abrasives, handpieces/nozzles and system controls. The abrasive is directed onto the surface to be sandblasted using compressed air (preferably filtered, free from oil and water) as a jet through a fine nozzle, made from a highly resistant material (e.g. Accurate focusing of the jet increases the sandblasting precision and at the same time reduces the material consumption. The blasting chamber forms a self-contained work area. Used abrasive is trapped by filter systems and extractors, preventing indoor air contamination. Separators remove contaminants from the abrasive. Viewing glass (the service-life is increased by using optional mesh guards), lighting and additional magnifying systems ensure a good view. Gloves (cuffs), which are permanently fixed in the unit housing, enable manipulation of the frameworks. Sandblasting is often activated using a foot-switch in order to keep the hands free. Precise coordination of sandblasting pressure, grit size of the abrasive and distance and angle of the nozzle to the framework to be sandblasted are crucial in ensuring optimum sandblasting in the least possible and therefore more cost-effective time. Modern sandblasters are suitable for universal use in all areas of application, e.g. ![]() Proper pronunciation requires a palatal seal between the prosthesis and the palatal soft tissues ( Figures 11-1 and 11-2).The removal of residual investment and metal oxides, roughening to create retentive surfaces, high-luster or matt sandblasting, compacting metal surfaces as well as special applications such as cold silanization for coating surfaces in the RocatecTM system. The gap allowed air to escape during speech and caused mispronunciation of dentoalveolar sounds. When turned upside down and used for the edentulous maxilla, however, it left a lot to be desired. This type of design was functional for the edentulous mandible. Therefore, the final design of the prosthesis left a gap between the intaglio surface of the prosthesis and the crest of the ridge. The Toronto bridge was a “high water” design because the abutments available at the time were standard abutments, which, by design, were at least 0.5- to 1-mm supragingival. Today, these prostheses are referred to as profile prostheses. The design of the hybrid prosthesis has evolved with the advent of new abutments such as the multiunit abutment, which allows a more natural and anatomically correct emergence of the prosthesis from the soft tissues. If the restorative dentist so chooses, pink porcelain and porcelain teeth may be substituted for the restorative reconstruction using the hybrid treatment concept. The term hybrid prosthesis (or the Brånemark or Toronto bridge) has become synonymous with a metal-based prosthesis that replaces missing soft and hard tissues with pink acrylic and missing teeth with acrylic teeth. A hybrid prosthesis is a prosthesis that replaces missing teeth and missing soft and hard tissues in a composite defect. ![]()
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