No abstract

No abstract

Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appropriate, the authors have added their opinions and guidance.KEY WOrDs: zirconia, dental ceramics, glassceramics, microwave sintering, spark plasma sintering, additive manufacturing. hree new ceramic-based materials have recently been introduced in dentistry: monolithic zirconia, zirconia-containing lithium silicate ceramics, and interpenetrating phase composites. These emerging restorative materials stem from very different technological approaches that are likely to lead to further developments. At this stage, it seems appropriate to provide a focused update on these new materials.

Over the past forty years, the technological evolution of ceramics for dental applications has been remarkable, as new materials and processing techniques are steadily being introduced. The improvement in both strength and toughness has made it possible to expand the range of indications to long-span fixed partial prostheses, implant abutments and implants. The present review provides a state of the art of ceramics for dental applications.

The application of home-bleaching procedures as a means of lightening multiple teeth has become increasingly popular. Very few studies, however, have determined the effect of this treatment upon dental hard tissues. This in vitro study evaluated the effects of a 10% carbamide peroxide gel on the apparent fracture toughness, hardness, and abrasion characteristics of human enamel. The apparent fracture toughness of enamel was reduced by about 30% after bleaching for a period of 12 hours with no significant change in surface hardness. Enamel treated with the bleaching gels also exhibited a small but significant decrease in abrasion resistance. This behavior was most likely due to an alteration of the organic matrix of enamel under the chemical action of hydrogen peroxide. Further investigation of the clinical significance of this process is needed.