The grinding efficiency by diamond points developed for yttria partially stabilized zirconia

Abstract

Recently, the use of all-ceramic restorations has increased and been applied for many types of clinical treatment such as bridges which can be made with high strength ceramic material: yttria partially stabilized zirconia (Y-PSZ) employing the CAD/CAM system. Consequently, points that can grind high strength ceramic material effectively are necessary for modifying the shape of restorations or removing them. So in our research, we fabricated new diamond points used to grind Y-PSZ. These points were made by electrodeposition of diamond grains. The diameter of the diamond grains are larger (200 µm) than that of traditional points (100 µm). High strength ceramic material was ground to assess the grinding weight and grinding depth various types of points. As a result, Y-PSZ could be ground efficiently with the diamond point which has a larger diameter and employs lager grains (200 µm).

Cutting efficiency of diamond burs operated with electric high‐speed dental handpiece on zirconia

“…As reported previously , it was demonstrated that the cutting efficiency of diamond burs on Zir depended on the grain size. However, even though diamond burs with SC grains were used, an increase of the thickness of Zir significantly decreased the cutting depth.…”

“…Cutting force was determined according to a previous study conducted by Siegel and von Fraunhofer , who reported that the mean cutting force applied by dentists was 99.3 ± 23.4 g (corresponding to 0.97 ± 0.23 N). The cutting force of about 0.9 N was also used in other studies, in which cutting efficiency was evaluated in relation to dental settings . However, cutting torque was not evaluated and controlled in the present study.…”

Surface Roughness of Monolithic and Layered Zirconia Restorations at Different Stages of Finishing and Polishing: An In Vitro Study

“…Zirconia can be processed by instruments coated with diamond abrasive grains because it has lower hardness than aluminum. It has been reported that higher grindability is achieved with larger diamond grains . However, the surface roughness is increased, so the rotary instrument should be changed sequentially from a large to small grain size of the diamond abrasives of the instrument.…”

“…Zirconia cores are often veneered with glass ceramics to achieve superior esthetics . More recently, monolithic full‐contour restorations have been fabricated using newly developed high‐translucency zirconia . Ceramic restorations routinely require occlusal and contour adjustments, resulting in a rough surface that may cause several problems, such as plaque accumulation, gingival inflammation, wear of the opposing teeth, and reduction of ceramic strength.…”

An Assessment of Burs Designed to Cut Zirconia

“…Ohkuma et al [5] tested diamond burs made by electrodeposition of diamond grains, with a larger diameter (200 µm) than that of traditional points (100 µm) designed to cut high strength ceramic material and found that yttria partially stabilized zirconia could be ground efficiently.…”