CA2375007C

CA2375007C - A dental camera

Info

Publication number: CA2375007C
Application number: CA002375007A
Authority: CA
Inventors: Harald Kerschbaumer; Walter Pokorny; Gottfried Rohner
Original assignee: Ivoclar Vivadent AG
Current assignee: Ivoclar Vivadent AG
Priority date: 2001-04-27
Filing date: 2002-03-07
Publication date: 2008-09-23
Anticipated expiration: 2022-03-07
Also published as: JP3644932B2; DE10120717B4; DE10120717A1; JP2002355263A; DE50206618D1; EP1252858A2; EP1252858B1; CA2375007A1; EP1252858A3; ATE324828T1

Abstract

A dental camera for obtaining a picture of an object in the mouth of a patient is provided and includes a light source for irradiating the object, a reflected light receipt element for receiving the light reflected from the object which may be, in particular, one or several teeth, and a mouthpiece. The mouthpiece has an opening therethrough which permits the passage therethrough of light to the reflected light receipt element, whereby the reflected light passes through the mouthpiece and is received by the reflected light receipt element. The light of the light source preferably passes through the mouthpiece.

Description

EXPRESS MAIL NO.: EL 803 540 390 US

A DENTAL CAMERA
Background of the Invention '~.
The present invention relates to a dental camera.

A conventional dental camera for determining the color of teeth is known from EP-At-376 647, In a conventional device of this type,.a light 5. source irradiates an object such as, for example, a tooth. The reflected light is captured or sensed by an optic capture device and is conducted to a reflected light receipt element. The reflected light receipt element is, in this conventional arrangement, configured as a spectrometer. With this.
arrangement, it is possible to specify or evaluate the color of an object.

This conventional arrangement relies upon a capture or sensing of light which is reflected at an angle from the surface of an object. This conventional arrangement is, for all practical purposes, operable only to sense scattered light so that the actual effective rate of light capture or sensing is substantially low.

A diagnostic device for use in the dental field, disclosed in D5-0S
33 45 465, permits a co-axial capture or sensing of the light reflected from a tooth. In this conventional arrangement, a light guide rod is provided which is overlaid by two light guide elements. The reflected light is guided to a photo resistor, which registers the brightness of the reflected light. By means of a filter, the capture or sensing of the reflected light can be adjusted to the respective spectrum which is desired to be observed.
1 2657-11-20,943 In this conventional arrangement, a determination or evaluation of the grade of reflection from the teeth is possible; however, it is, for substantially all practical purposes, not possible to effect a color comparison of a tooth in order to thereby specify a suitable replacement tooth.

In connection with evaluation of color, it is especially important that the lighting situation be reliably reproducible. The light source comprises a predetermined emission spectrum and the reflected light receipt element -that is, for example, a CCD-cell - operates at a predetermined spectral sensitivity. In connection with avoiding a false color sensing, it has become known to undertake a so-called white color comparison. A unit comprising a light source and a reflected light receipt element can be calibrated by use of such a white color comparison. The calibration is, of course, relevant for the respective unit only under the same lighting circumstances.
If, for example, a bulb is used as a light source and a bulb exchange of the existing bulb for another bulb is necessary, a renewed or refreshed white color comparison must be undertaken. Also, in connection with such white color comparisons, the conventional diagnosis devices reveal only partial color deviations.

Summary of the Invention In accordance with one aspect of the present invention, there is provided a dental camera mouthpiece, comprising a body that comprises: a light channel associable with a dental camera for permitting passage of light therethrough to the camera; a first attachment portion configured for attaching the body to the camera with the light channel positioned to permit the passage of light to a light receiving element of the camera; a wing extending radially from the light channel and configured and dimensioned for placement with respect to lips and teeth of a patient for substantially blocking light from entering the light channel from outside the wing when the mouthpiece is attached to the camera; a reference sample element configured for directing light with predetermined qualities to the light receiving element for calibrating the camera, and an attachment portion configured and dimensioned for removably mounting the reference sample element, wherein the color of the reference sample element is a white color.

In accordance with a second aspect of the present invention, there is provided a dental camera, comprising: a light receiving element, which is configured for receiving light and producing an image based on the received light; a mouthpiece, comprising a body that comprises: a light channel associable with the camera for permitting passage of light therethrough to the camera, a first attachment portion configured for attaching the body to the camera with the light channel positioned to permit the passage of light to the light receiving element of the camera, and a wing extending radially from the light channel and configured and dimensioned for placement with respect to lips and teeth of a patient for substantially blocking light from entering the light channel from outside the wing when the mouthpiece is attached to the camera; and a second attachment portion configured for attaching to the first attachment portion for positioning the mouthpiece with respect to the light receiving element for permitting the passage of light through the light channel to the light receiving element.
In accordance with a third aspect of the present invention, there is provided a dental camera mouthpiece, comprising: a light channel associable with a camera 2a housing for permitting passage of light therethrough to a receiving element, a first attachment portion configured for attaching to the camera housing with the light channel positioned to permit the passage of light to the receiving element, a wing extending radially from the light channel and configured and dimensioned for placement with respect to lips and teeth of a patient for substantially blocking light from entering the light channel from outside the wing when the mouthpiece is attached to the camera, and a bite projection portion that is disposed on the wing and vertically off-center with respect to the light channel, and configured and dimensioned for placement between upper and lower teeth of the patient for positioning the light channel and teeth with respect to each other for producing images of the teeth based on the light passed through the light channel to the receiving element.

In accordance with a fourth aspect of the present invention, there is provided a dental camera, comprising: a housing; a light source mounted to the housing and configured for emitting light; a receiving element mounted to the housing and configured for receiving reflected light and producing an image based on the received light; a mouthpiece mounted to the housing and configured for contacting a patient's mouth for positioning the camera with respect to at least a portion of the mouth; a light channel associated with the light source for permitting the emitted light to reflect off a tooth in a patient's mouth and permitting the reflected light travel into the receiving element; and a sound receiving element configured for receiving sound for storing in association with the image, wherein the mouthpiece comprises a wing extending radially from the light channel and configured and dimensioned for placement between a lip and teeth of the patient for 2b substantially blocking light from entering the light channel from outside the mouth.

Embodiments of the present invention offer a solution to the challenge of providing a dental camera which makes possible a reliable and precise 2c color evaluation and, especially, is operable independent of the hand-held position of the dental camera.

The dental camera of the present invention permits, in a surprising manner, the possibility to reliably determine, with simple means, the color trueness of an object. In accordance with the present, invention, a mouthpiece is provided which, in the conventional manner of a mouthpiece, permits the disposal thereof in the space between the lips of a patient and, in this manner, ensures the blocking off of undesired fight which is different than the light specified for the operation, In contrast, undesired outside light typically enters into and irradiates a mouth region of a patient if an annular pipe or conduit passes through the space between the patient' s lips for the reason that a complete sealing around the space between the lips is not possible. In accordance with the present invention, it is provided that the light solely falls upon the reflected light receipt element; however, it is also preferably provided that only light from the light source passed through the mouthpiece falls upon the tooth so that a false reading corrupted by undesired outside light will not occur.

In a particularly advantageous embodiment of the dental camera of the present invention, it is provided that the mouthpiece operates, at the same time, to provide reference points for the orientation of the dental camera relative to the tooth of interest. These reference points function 3 2657-II=20.943 at the same time as spacer or standoff distance fixing elements so that the dental camera is always centered and fixedly positioned at the same uniform standoff distance from the tooth surface. The analysis of front teeth by the camera at a fixed and centered uniformed standoff distance is possible without additional measures by the provision of bite projections which extend from side wings of the mouthpiece to the teeth and are each horizontally oriented. Preferably, the dental camera includes a flat display screen for permitting the exact positioning of the camera in the horizontal direction which thus permits the immediate recognition or identification of the tooth which is to be evaluated.

Preferably, a so-called CCD sensor or another suitable sensor is provided for receipt of the picture, whereby the selected reflected light receipt element is characterized by a good resolution of the captured picture. The dental camera also operates, in this connection, to intermediately store the received picture or, in accordance with another configuration of the inventive dental camera, to immediately transfer the received picture via an interface, which is connected in either a wireless manner or a wired manner, to a further location for evaluation of, and follow up work on, the picture.

?0 Preferably, the mouthpiece includes a flat right-angled opening which is dimensioned such that it permits the simultaneous evaluation of at least two teeth. The light source is preferably integrated into the dental 4 1657-II-20.943 camera and its emission of light follows in a substantially co-axialN manner with the receipt of reflective light through the opening in the mouthpiece so that the creation of shadows is prevented. A conventional polarization filter can be provided to shut out or preclude undesirable reflections.

Also, while it is possible to provide for the transfer or through passage of light through the mouthpiece via a light guide element, it is preferable to provide solely one open channel through which the light passes. Preferably, the reflected light receipt element is then blocked off by conventional black side walls so that no immediate or direct irradiation of the reflected light receipt element by the light from the light source can occur. It is also possible to couple the light source to a light guide element and to undertake the light irradiation of the object to be evaluated - that is, for example, the tooth - in a direct manner relative to this object so that special measures for blocking off the reflected light receipt element against false light are not necessary.

The outer configuration of the mouthpiece in the region of the lip gap is preferably also of a flat right-angled geometry with rounded-off corners. Also, if this outer configuration does not fully permit a complete sealing off from the lips, the penetration of false light still need not be feared as the opened area is covered by the side wings of the mouthpiece which each extend to respective sides of the mouthpiece opening, S 2657-11-20.943 The mouthpiece can be comprised of any suitable desired material such as, for example, plastic or polymeric material, whereby a black color or, at least, a non-light transmitting color, is preferred. The mouthpiece is, for hygienic reasons at least, preferably disposable and is mountable via a coupling to the dental camera. The inner radii of.the mouthpiece are configured to be relatively large so that a cleaning of the mouthpiece is relatively easy.

A color reference sample is preferably integrated into the mouthpiece by which a color evaluation of the tooth with the camera can be conducted such that a calibration of the camera is possible. The color evaluation follows after the camera is focused on the row of teeth following the positioning of the mouthpiece in the mouth of the patient, with the assistance of the bite projections or other distance standoff fixing elements. Preferably, the mouthpiece is comprised of at least two plastic materials having differing hardness or differing elastic properties in order to ensure an optimal disposal or mounting of the mouthpiece on the teeth structure and relative to the gums. As suitable material, rubber, silicone, or other plastic materials having a hardness up to that of elastic polymeric materials can be considered.

Brief Description of the Drawings Further details, advantages, and features of the dental camera of the present invention are provided in the hereinafter following description 6 2657-11-20.943 ~ . .. .

~Y .

of one embodiment of the dental camera taken in connection with the figures of the drawings, in which:

Fig.1 is a perspective view of one embodiment of the dental camera of the present invention;

Fig. 2 is a perspective view of a mouthpiece for the one embodiment of the dental camera of the present invention shown in Figure 1; and Fig. 3 is a unit comprising a light source and a reflected light receipt element of the one embodirnent of the dental camera of the present invention shown in Figure 1.

Detailed Description of the Preferred Embodiment As seen in Figure 1, a dental camera 10 of the present invention includes a mouthpiece 12 which extends sideways at a transverse orientation from a side of the dental camera. In this connection, a coupling 14 is provided which is encircled by a coupling sleeve 16 of the mouthpiece 12 in a light-sealing manner and is removable therefrom.
The dental camera 10 comprises an overall flat right-angled configuration with rounded-off corners. On the upper side of the dental camera, which is turned toward the dentist or dental technician in its deployment, a display screen 18 is provided which displays the just received picture. The display screen 18 is configured as'a liquid crystal 7 2657-11-20.943 , _..._......~._ __ display so that the camera corresponds, to this extent, to a commercially available digital camera.

The dental camera 10 includes a reflected light receipt element as well as a light source, these elements being shown in Figure 3.
Furthermore, the dental camera includes a connection for the transfer of the received pictures in data form to a computer which can be configured for the evaluation of, and the follow up work on, the pictures. Additionally, the dental camera includes a suitable voltage supply such as, for example, a battery or an accumulator, so that a cordless operation of the camera is also possible and the hand deployment of the camera is facilitated.

In a modification of the dental camera of the present invention, the display screen 18 is pivotably mounted so that the display screen can be tilted to accommodate the viewing angle of the operator - thus, especially, the display screen can be tilted to accommodate the viewing angle of a dentist.

While the configuration of the one embodiment of the dental camera shown in Figure 1 comprises a right-angled orientation of the coupling 14 relative to the camera, it is to be understood that other suitable configurations are possible. For example, it is possible to select the angled orientation of the coupling 14 relative to the balance of the dental camera 10 such that the coupling 14 extends at an angle to the 8 2657-I1-20.943 , ..e...._..w__.._..

longitudinal extension of the main body of the dental camera 10. In a further modification of the one embodiment of the dental camera, it is provided that the position of the coupling 14 relative to the main body of the dental camera 10 can be adjusted.

The dental camera 10 supports the mouthpiece 12 in a manner such that the mouthpiece 12 can be removed therefrom only by the application of a considerable force such as, for example, a force of 100 Newtons. In this manner, it is ensured that the mouthpiece cannot inadvertently be detached while in the mouth of a patient. The coupling 14 has a substantially large inner diameter or cross-section. In contrast thereto, the mouthpiece 12 tapers down in the area of the lips to form a lip through passage channe! 20. In this area, the outer diameter or cross-sectional dimension is substantiaily flat and right-angled and is approximately 1 centimeter high. The rriouthpiece 12 extends transversely along two side wings 22 and 24 each of which extends in a curved manner and follows the tooth curvature of the patient.

As can be seen in Figure 1, the configuration of the mouthpiece 12 in a conventional manner ensures a certain stiffness. The side wings 22 and 24 are, however, substantially more flexible and softer than the middle region of the mouthpiece and these side wings extend in a rounded-off manner so that the danger of injury to a patient is exceptionally low.

9 2657-Ii-20.943 Moreover, the mbuthpiece 12 is preferably formed of a soft rubber or other suitable materials, Further detaiis of the one embodiment of the dental camera of the present invention are shown in Figure 2. In this figure of the drawings, as well'as the other figures of the drawings, like elements are designated with the same reference numbers. The mouthpiece 12 includes an opening 26 which extends into the middle region 28 of the mouthpiece 12. The opening 26 is, in correspondence with the configuration of the lip through passage channel 20, configured in a flat right-angled configuration with rounded-bff corners.

As can be seen in Figure 2, each of the side wings 22 and 24 is provided with a bite projection 30, 32, respectively. In this manner, a frm fixing of the position of the mouthpiece 12 and, thus, of the dental camera 10, can be effected without further measures. In the illustrated embodiment, the upper as well as the lower front teeth can be irradiated and the light reflected thereby can be received by the dental camera 10 in that the bite projections 30 and 32 are each arranged approximately in the vertical middle and the receipt field, to this extent, comprises a Sufficient dimension. In this embodiment, at least four teeth can be simultaneously irradiated and evaluated and it is possible to obtain a picture cross-section which is accommodated to the desired color specification requirements.

10 2657-II-20.943 The middle region 28 includes a receipt slot for mounting a reference sample element 33 to the dental camera which is immediately neighboring the tooth to be evaluated.- In this manner, a direct color comparison is possible.

In the illustrated embodiment of the dental camera of the present invention, the opening 26 is configured as a through passage. It is to be understood that, without the provision of any further means, it is possible to provide a protection screen in order to protect the reflected light receipt element shown in Figure 3. Also, in any desired suitable manner, the receipt optics can be provided such as, for example, through the opening 26 or by additional lenses or the like. It is also possible to connect a light guide element or a light guide rod to the reflected light receipt efement.

As is shown in Figure 3, an arrangement for receipt and production of the light is comprised of eight light diodes or laser diodes 40 which collectively form a light source 42 that is arranged in an annular manner around a reflected light receipt element 44. The light source 42 and the reflected light receipt element 44 are mounted on a base unit 46 in a fixed relative position to each other. By means of the annular arrangement of the light diodes 40, a shadow-free illumination of the area to be evaluated is possible.

It is to be understood that the light source can be configured in any desired suitable manner. For example, yellow, blue, and red light diodes l 1 2657-11-20.943 , . _ _ _......_..._..._..._.. __ can be distributed in a uniform manner therearound in order to emit a white light. It is also possible to use white light diodes or other different suitable light sources. A
small tube or conduit 48 extends around the reflected light receipt element 44 and extends in a forward manner to the coupling 14. In this manner, a false lighting of the reflected light receipt element by the non-reflected light directly from the light source 42 is foreclosed.

The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.

Claims

1. A dental camera, comprising:

a light receiving element, which is configured for receiving light and producing an image based on the received light;

a mouthpiece, comprising a body that comprises:
a light channel associable with the camera for permitting passage of light therethrough to the camera, a first attachment portion configured for attaching the body to the camera with the light channel positioned to permit the passage of light to the light receiving element of the camera, and a wing extending radially from the light channel and configured and dimensioned for placement with respect to lips and teeth of a patient for substantially blocking light from entering the light channel from outside the wing when the mouthpiece is attached to the camera; and a second attachment portion configured for attaching to the first attachment portion for positioning the mouthpiece with respect to the light receiving element for permitting the passage of light through the light channel to the light receiving element.

2. The dental camera of claim 1, wherein the first attachment portion is substantially stiffer than the wing.

3. The dental camera of claim 1, wherein the mouthpiece attachment portion comprises a blocking member associable with the camera for substantially blocking entry of light between the camera and light channel from outside the camera, light channel, and the patient's mouth.

4. The dental camera of claim 1, wherein the mouthpiece further comprises a bite projection portion extending adjacent the wing and configured and dimensioned for biting by the patient to stabilize and position the camera with respect to the mouth.

5. The dental camera of claim 4, wherein the bite projection portion extends from the wing.

6. The dental camera of claim 5, wherein the bite projection portion extends on each lateral side of the light channel.

7. The dental camera of claim 1, wherein the light channel defines an opening extending through the channel.

8. The dental camera of claim 1, wherein the wing extends radially from the light channel in a direction along the separation between the teeth of the upper and lower jaws of the patient.

9. The dental camera of claim 8, wherein the wing extends radially from the light channel in a direction transverse to the separation between the teeth of the upper and lower jaws of the patient.

10. The dental camera of claim 1, further comprising a light source configured and disposed for emitting light through the light channel and upon one or more teeth of the patient, and for receiving light that is reflected from the one or more teeth and directing the received light back through the light channel to the receiving element.

11. The dental camera of claim 1, wherein the light channel has a width sufficient for allowing passage therethrough of sufficient light reflected from at least two teeth of the patient back to the receiving element to form an image of the at least two teeth.

12. The dental camera of claim 1, wherein the camera is configured, dimensioned, and has a weight for enabling handheld operation with a single hand for producing an image of the patient's tooth or teeth.

13. The dental camera of claim 1, wherein the first and second attachment portions are separably attachable to each other.

14. The dental camera of claim 1, wherein the wing has a distal surface that is substantially concave for placement against the teeth.

15. The dental camera of claim 1, wherein the mouthpiece body includes a reference sample element with predetermined reflective qualities and disposed for reflecting the emitted light to the receiving element adjacent the light reflected from the teeth.

16. The dental camera of claim 1, further comprising an image transfer member for transferring the image to a color analyzer for determining the color of a portion of the patient's mouth.

17. The dental camera of claim 1, further comprising:
a housing associated with the light receiving element and second attachment portion; and color analyzing electronics mounted to the housing and connected to the receiving element for receiving the image and configured for determining the color of a portion of the patient's mouth.

18. The dental camera of claim 17, further comprising:
a processor mounted to the housing; and input keys connected with the processor for operating the camera and color analyzing electronics.

19. The dental camera of claim 1, further comprising:
a housing; and a display mounted to the housing and associated with the receiving element for displaying the image.

20. The dental camera of claim 19, wherein the display is movably mounted to the housing for tilting to adjust an angle between the light channel and the display.

21. The dental camera of claim 19, wherein the display is mounted to the housing in a position in which the image on the display is viewable from a side of the housing opposite from the light channel.

22. The dental camera of claim 19, wherein the housing comprises a first elongated portion and an elongated handle connected to the elongated portion at an angle thereto, wherein the mouthpiece is mounted at an end of the first elongated portion.

23. The dental camera of claim 22, wherein the display is mounted at an end of the elongated portion opposite from the mouthpiece.

24. The dental camera of claim 19, further comprising a sound receiving element configured for receiving sound for storing in association with the image.

25. The dental camera of claim 24, further comprising a storage medium mounted to the housing and connected with the light and sound receiving elements for recording images and sounds in association with each other.