Coated dental articles and related methods of manufacture

摘要

Provided are dental articles, and methods of making articles, having an aesthetic inorganic coating based on zirconia at least partially stabilized with yttrium oxide, calcium oxide, cerium oxide, or magnesium oxide. Stabilized zirconia coatings were found to provide a smooth, low friction surface having high abrasion resistance. These coatings are particularly applicable to orthodontic appliances. While virgin stabilized zirconia coatings can often have an undesirable color cast, it was discovered that this color cast can be substantially eliminated by heat treating the coated appliance in an oxygenated environment. The combination of depositing a stabilized zirconia coating and subsequently heat treating to decolorize the coating provides a surprisingly robust, stable, low-friction coating that is also aesthetic.

主权项

1. A method of making a coated dental article, the method comprising:
providing a dental article having an outer surface; and depositing on at least a portion of the outer surface a coating comprising zirconia that is at least partially stabilized by an alloying compound selected from the group consisting of yttrium oxide, calcium oxide, cerium oxide, magnesium oxide and combinations thereof, wherein depositing the coating takes place at a pressure of 10 millitorr or less; and heat-treating the coating in an oxygenated environment at a temperature ranging from 300 to 700 degrees Celsius, wherein the coating has a layer thickness ranging from 400 to 700 nanometers wherein the coating after heat-treating exhibits enhanced abrasion resistance as evidenced by a lack of chipping after 16000 cycles of the Abrasion Resistance Test; and wherein the dental article is an orthodontic bracket having an archwire slot, and wherein the coating is deposited on a least a portion of the archwire slot.