Abstract:
The invention relates to a device for measuring dental shade comprising: - illumination means (24, 40, 42, 44, 48, 50), for successively illuminating at least one part of a tooth (D) with light of various spectral ranges, - at least one sensor (26) sensitive to light coming from said tooth part, in response to the illumination, to generate for each different color of illumination, at least one measurement signal, - means (30, 32) for converting the measurement signals corresponding to said tooth part, into the coordinates of a measurement point (202), in a shade space in which "reference" points (320, 410, 540) are also defined, corresponding to the preset shades of a dental shade guide, and - search means (114), for the tooth part, for a shade corresponding to the reference point closest to the measurement point, in the shade space.
Abstract:
An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses colorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.
Abstract:
A method and systemof image processing on a computer, and a computer program product adapted for image processing, wherein a digital image of an article is improved into a computer, the digital image is colour-corrected, an internal palette is generated from a database of predetermined colour attributes and applied to teh colour-corrected digital image so as to generate a second digital image, and wherein a third digital image corresponding to the second digital image is generated, but replacing the predetermined colour attributes with vivid colour attributes. The present invention is of particular utility in the manufacture of dental prestheses from ceramics materials which substantially match a person's natural tooth colours.
Abstract:
A digital camera (12) connects to a tooth shade analyzer subsystem, e.g., a digital video processor (14), and a color display monitor for the electronic determination of the color of patient's teeth. Preliminarily, the camera captures (26) a series of digital color images of tooth shades corresponding to reference shade guides (34), and electronically compares the reference shades to an image of the patient's tooth. In a preferred embodiment the comparison is done over a set of pseudo-pixels, each corresponding to a group of pixels in an high-resolution camera. Once a match is found, it is communicated to a user of the system (52). In a specific embodiment the camera is equipped with a sleeve and illumination subsystems that help reduce the variations in the color of digital images due to external factors.
Abstract:
An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses colorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.
Abstract:
The device of the invention includes a spectrocolorimeter (1) for analyzing the colour of the dental structure (2, 3) near the site (4) of the restoration to be effected, a dispenser (9) of given and adjustable quantities of basic components, different dyes, in paste or gel form, and a mixer (19) positioned at the outlet of the dispensor (9) for preparing a blend of at least two components. The device also includes a programmed data processing unit with the colorimetric features of each of the basic components stored in its memory, the device being connected via its inputs to the spectrocolorimeter (1) and to a manual element (6) for introducing the quantity of the required material. Said data processing unit is connected via its outputs to the dispenser (9) and the mixer (19), so as to control, after computation, the number and quantities of the components to be dispensed as well as their blending with a view to obtaining the desired quantity of material of the colour analyzed.
Abstract:
A shade distinguishing device comprising a casing (6) having a light source (1) and detector (2). The light source and detector being relatively positioned so that a proportion of the light emitted by the detecteur, and falling incident on an object, is reflected onto the detector. The proportion of the light detected being dependent on the colour and shade of the object. The signal from the detector being processed to produce an accurate signal representative of the shade and colour of the object, which is displayed on a liquid crystal display (3).
Abstract:
Method for determining the color of an object (10), such as a tooth, by measuring its diffuse spectral reflectance by means of a spectrometer (20), detectors (22) and electronic processing circuits (24, 26, 28) associated with a microprocessor (32), the method consisting in determining the total chromatic difference between the color of the tooth and the colors of a sample chart within a uniform space L*, a*, b*, and the root-mean-square deviation between the diffuse spectral reflectance of the tooth and that of the colors of a sample chart in order to determine the color of the prothesis.
Abstract:
A device for exactly determining the colour of a dental prosthesis to be applied, or of the material to be used in dental pluggings, so as to make it perfectly identical to the colour of the patient's teeth. Comprising a light source (1), which sends light rays over a monochromator (2), which, by means of an optical switcher or chopper (3), separates the monochromatic light rays into at least two parallel circuits (4, 4a, 5, 5a), the one (4, 4a) including a housing or cell (6) for at least one of the patient's teeth (9), the other, (5, 5a), comprising a reference cell (7), which includes a white-coloured reference sample (28). Said circuits head up at a device (8) that detects and compares the rays coming from cell (7) and those that have passed through cell (6) and the tooth or teeth (9), providing a sequence of signals that are applied to a detector (8), which are then duly amplified and applied to a digital-analogical convertor (12), which is hooked up to a data processor or computer (10), which provides the coded identification data on the colour as identified.