A method includes determining depth values associated with a first set of pixel locations in a first image of a mouth. One or more function is generated for one or more color channels based on intensities of the one or more color channels at the first set of pixel locations and depth values associated with the first set of pixel locations. Image data comprising a new representation of the teeth is received, wherein the image data comprises a second set of pixel locations and new depth values associated with the second set of pixel locations. A new image is generated based on the image data and the one or more functions.

Disclosed in a method, a user interface and a system for use in determining shade of a patient's tooth, wherein a digital 3D representation including shape data and texture data for the tooth is obtained. A tooth shade value for at least one point on the tooth is determined based on the texture data of the corresponding point of the digital 3D representation and on known texture values of one or more reference tooth shade values.

A method for monitoring the shape of teeth including: producing a three-dimensional digital model of at least one portion of an arch of the patient or “initial reference model”; acquiring at least one two-dimensional image of the arches, referred to as “updated image”, under actual acquisition conditions; analysing each updated image and producing an updated map relating to a piece of discriminating information; optionally determining rough virtual acquisition conditions that approximate the actual acquisition conditions; searching each updated image for a final reference model corresponding to the shape of the teeth, and optionally to the positioning of the teeth, during the acquisition of the updated image; and comparing the shapes of the initial reference model and of the reference model obtained at the end of the preceding steps, referred to as “final reference model”, in order to determine the deformation and/or the movement of teeth between steps a) and b).

An embodiment of the invention is a method for automatic calibration of dental furnaces, there is made available a dental furnace comprising a control unit adapted to control the dental furnace for performing a firing process defined by firing process parameters such as e.g. the temperature and/or a temporal temperature curve and/or a temperature gradient and/or a vacuum in a firing chamber of the dental furnace. There is provided at least one calibration firing-object sample made of a dental material, where said dental material, after said calibration firing-object sample has been subjected to a calibration firing-object process with predetermined firing process parameters, has a defined desired color stored e.g. in the control unit. Further, a color measuring device is used which, for transmission of measurement signals and/or measurement results, is operatively connected to the control unit.

A shade selection program is disclosed that predicts the shade choice with the smallest CIEDE2000 color difference for dental composite resin restorations when given a backing and target shade. By utilizing generated regression models, a database of spectral reflectance information, and principles of Kubelka-Munk layering, a highly accurate shade selection program was designed. Additionally, a blending model for quantification of color adjustment potential was developed. Systems and methods for correlating RGB data from the VITA Linearguide 3D Master and VITA Bleached Guide 3D Master shade guides with their spectroradiometric correlates through a regression model while indicating a methodology for validation of accuracy of digital imaging systems are disclosed.

The invention relates to a system and a method for determining the color of teeth or tooth surfaces, wherein the system comprises a 2D or 3D camera and an attachment on said camera, which sets a geometry of a captured image in such a way that, compared to capturing an image without the attachment, the distance, spatial angle and orientation of tooth surfaces relative to the camera are restricted. The attachment according to the invention can in particular be fitted to the camera in a simple manner.

A process for determining a tooth color of a filling or another restoration is provided which in particular is produced using composite materials, wherein at least one tooth is scanned or is visually detected. The process is characterized in that natural teeth are spectrally measured in advance, that the color values measured within a color space are classified into several, in particular four, categories which each form a color cloud extending in a three-dimensional fashion within the color space, which is done with the help of a structuring algorithm, in particular a Nearest Neighbour Algorithm, or a symmetry recognition algorithm, and that the tooth color of the filling is determined by means of evaluating to which category the tooth scanned has the smallest color distance, or to which color cloud the tooth scanned belongs.

A device and method and system for utilizing confocal measurement and an optical arrangement to produce 3D color images. A color measurement optical path and a 3D measurement optical path may coincide at least at an object side of the device, and a minimal amount of light is extracted from a monitoring beam for color measurement without affecting 3D measurement.

An acquisition kit, including: a mouthpiece intended for being placed into the mouth of a patient and including a reference mark; and an image-acquisition apparatus including a screen for viewing an image that can be acquired, computer memory containing information on target acquisition conditions, and a computer program comprising program code instructions for displaying on said screen a reference in a position such that, when the reference mark matches the reference on the screen, the acquisition apparatus complies with the target acquisition conditions.

Method for providing a natural colour and optical depth to a dental object comprising the steps: providing a framework of the dental object, taking an object colour picture of an adjacent dental object or reference dental object, and uploading the object colour picture into a computing device, calibrating and adjusting the uploaded object colour picture into a target object colour picture in a computing device, (pre)determining the thickness profile of the enamel material to be applied on the framework, correcting in a computing device of the digital picture elements of the target object colour picture for the thickness profile of the enamel material to be applied on the position of the digital picture elements and providing a print colour picture of the corrected digital picture elements, printing the print colour picture as a print layer on the framework, applying the enamel material in the predetermined profile-thickness upon the print layer upon the framework.