Feedback data useful in prosthodontic procedures associated with the intra oral cavity is provided. First, a 3D numerical model of the target zone in the intra oral cavity is provided, and this is manipulated so as to extract particular data that may be useful in a particular procedure, for example data relating to the finish line or to the shape and size of a preparation. The relationship between this data and the procedure is then determined, for example the clearance between the preparation and the intended crown. Feedback data, indicative of this relationship, is then generated, for example whether the preparation geometry is adequate for the particular type of prosthesis.

Feedback data useful in prosthodontic procedures associated with the intra oral cavity is provided. First, a 3D numerical model of the target zone in the intra oral cavity is provided, and this is manipulated so as to extract particular data that may be useful in a particular procedure, for example data relating to the finish line or to the shape and size of a preparation. The relationship between this data and the procedure is then determined, for example the clearance between the preparation and the intended crown. Feedback data, indicative of this relationship, is then generated, for example whether the preparation geometry is adequate for the particular type of prosthesis.

A three-dimensional printing system including a feed source of uncured filled resin material, a print head configured to apply discrete layers of a composition including upconversion phosphors, and a radiation source configured to irradiate layers of uncured filled resin material and deposited layers of the composition is provided. A method of three dimensionally printing a dental article is also provided.

A three-dimensional printing system including a feed source of uncured filled resin material, a print head configured to apply discrete layers of a composition including upconversion phosphors, and a radiation source configured to irradiate layers of uncured filled resin material and deposited layers of the composition is provided. A method of three dimensionally printing a dental article is also provided.

An assembly useful for preparing a prosthetic crown for fitting to a tooth of a patient is accordingly described herein. The assembly includes (a) a polymer dental model having a shape corresponding to at least a portion of a dental arch of a patient and a socket formed therein, the socket having a socket wall, and (b) a polymer die having an upper portion configured in the shape of a tooth of a patient and a lower stem configured for insertion into the socket. At least one of the stem and the socket wall are configured to have both a relaxed position when the die is not in the socket, and a tensioned position when the die is fully inserted in the socket, so that the stem is firmly and accurately engaged by the socket when the die is inserted therein.

An assembly useful for preparing a prosthetic crown for fitting to a tooth of a patient is accordingly described herein. The assembly includes (a) a polymer dental model having a shape corresponding to at least a portion of a dental arch of a patient and a socket formed therein, the socket having a socket wall, and (b) a polymer die having an upper portion configured in the shape of a tooth of a patient and a lower stem configured for insertion into the socket. At least one of the stem and the socket wall are configured to have both a relaxed position when the die is not in the socket, and a tensioned position when the die is fully inserted in the socket, so that the stem is firmly and accurately engaged by the socket when the die is inserted therein.

Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools and which subsequently can be converted into lithium silicate products showing high strength.

Lithium silicate materials are described which can be easily processed by machining to dental products without undue wear of the tools and which subsequently can be converted into lithium silicate products showing high strength.

Glass ceramics having SiO.sub.2 as main crystal phase and precursors thereof are described which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

The invention relates to a method for the preparation of a glass ceramic or a glass, which comprise cerium ions and are suitable in particular for the preparation of dental restorations, the fluorescence properties of which largely correspond to those of natural teeth. The invention also relates to a glass ceramic and a glass which can be obtained using the method according to the invention, the use thereof as dental material and in particular for the preparation of dental restorations, as well as a glass-forming composition which is suitable for use in the method according to the invention.