GB2321194A

GB2321194A - Indicator for detection of dental deterioration in dentures

Info

Publication number: GB2321194A
Application number: GB9809017A
Authority: GB
Inventors: Peter John Charlton
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-06-19
Filing date: 1998-04-29
Publication date: 1998-07-22
Anticipated expiration: 2018-04-29
Also published as: GB9809017D0; GB2321194B

Abstract

An artificial tooth (1) for incorporation into a dental plate has an indicator (3) buried therein. The indicator (3) is of a material providing a coloured appearance that is visually different from adjacent parts of the tooth (1). The indicator (3) is positioned within the tooth so as to be exposed when the tooth is subject to a predetermined amount of wear, thereby providing a visual indicator of that wear.

Description

INDICATOR FOR DETECTION OF DENTAL DETERIORATION IN ARTIFICIAL DENTURES This invention relates to dentures, and in particular to a means for detecting the deterioration of artificial teeth in dentures.

Dentures, or dental plates, inevitably undergo abrasive or attritive deterioration, as a result of the teeth rubbing against one another, or due to mechanical or chemical deterioration caused by other agents in the mouth. When teeth at the rear of the upper or lower dental plates become worn, this can cause acute problems to the wearer, since the anterior portions of the dentures are then bought into abrasive contact and rub against one another. The resultant shearing action can cause teeth at the front of the mouth to be displaced, such that they fall out. This may cause discomfort and distress to the denture wearer.

The present invention seeks to detect this process of deterioration of the artificial teeth at the occlusal surface of the dental plates, so that the user can monitor the state of the teeth and determine when the dentures need to be replaced.

In one aspect of the present invention, there is thus provided an artificial tooth for incorporation into a dental plate. The tooth has an indicator buried therein, which indicator is of a material providing a coloured appearance that is visually different from adjacent parts of the tooth. The indicator is positioned within the tooth so as to be exposed when the tooth is subject to a predetermined amount of wear, thereby providing a visual indicator of that wear.

Preferably, the indicator is inherently visually different from adjacent parts of the tooth under normal light conditions, but it will be understood that other ways of achieving a visual difference may be equally effective. Hence, for instance, the indicator may become visually different only in response to ultra violet radiation. Alternatively, the visual difference may be effected in response to a chemical agent applied to the denture by the user in order to monitor the exposure of the indicator.

The indicator may be positioned in the tooth either during the tooth's manufacture, or at a later stage.

The tooth may include a capping layer, the layer being of a material providing a coloured appearance which is different from both the indicator and adjacent parts of the tooth. This layer is disposed approximately flush to the wearing surface of the tooth, and masks said indicator until both the tooth and the layer have been subject to said predetermined amount of wear.

In one embodiment, the coloured appearance of the indicator changes in response to an agent in the mouth to which it becomes exposed after said predetermined amount of wear, the modified appearance of the indicator providing a visual difference from adjacent parts of the tooth. The agent may be a mouth acid. Alternatively, the agent may be enzymatic.

In a second aspect of the invention, a dental plate is provided having at least one artificial tooth according to the first aspect of the invention.

In a further aspect of the invention, there is provided a method of detecting the requirement to replace a dental plate, including the steps of: (i) burying an indicator in an artificial tooth1 which indicator is of a material providing a coloured appearance that is visually different from adjacent parts of the tooth, the indicator being positioned within the tooth so as to be exposed when the tooth is subject to a predetermined amount of wear, thereby providing a visual indicator of that wear; (ii) constructing a dental plate to include at least one said tooth having an indicator buried therein; and (iii)monitoring the at least one said tooth to detect the exposure of the indicator.

The present invention will be better understood by reference to the accompanying figures, in which: Fig. 1 is a plan view of a tooth according to one embodiment of the present invention.

Fig. 2 is a longitudinal section of the tooth shown in Fig. 1.

Fig. 3 is a plan view of a dental plate, showing artificial teeth according to the present invention.

Fig. 4 is a longitudinal section of a tooth according to a second embodiment of the present invention.

Fig. 5 is a perspective view of the tooth shown in Fig. 4.

Fig. 6A is a perspective view of a tooth according to a third embodiment of the present invention.

Figure 6B is a side view of the indicator and capping layer disposed in the tooth shown in Figure 6A.

Fig. 7 is a plan view of the tooth in Fig. 6.

Referring to Figures 1 to 3, the artificial tooth 1 is made from an inert durable material, as is known in the art. In a generally conventional way, the tooth is shaped to fit into a dental plate 5, such that it can perform the normal functions of a tooth in that position in the jaw of the subject. In the embodiment shown in these figures, the tooth is constructed to include, in its core, an indicator 3 of wear of the tooth. The indicator, which is a coloured plate or disc, is buried beneath the end surface 2 of the tooth 1. It is retained in place in the tooth by a physical or chemical retainer, 4.

Initially, when the new tooth is fitted into the dental plate, the indicator 3 is invisibly disposed in the tooth, such that it can only be seen when the tooth has become worn away at its end surface 2. Thus, when the tooth has been worn by a predetermined amount of wear, the indicator becomes visible to the user, and indicates that the dental plates must be replaced. In this way, by disposing the indicator at a specified depth within the tooth, deterioration of the tooth can be monitored, the indicator clearly showing whether the tooth has been worn beyond the selected threshold.

Figure 3 shows a dental plate, which may be an upper or lower plate, including two teeth in which a visual indicator is incorporated. The teeth are disposed at a location towards the rear of the plate, such that they are located at the sites in the mouth most prone to deterioration by abrasion or attrition.

In a second embodiment, shown in Figures 4 and 5, the indicator 13 comprises a pH-sensitive layer, incorporated beneath the end surface 12 of the tooth 10.

When the layer becomes exposed to the internal environment of the mouth, by wear at the end surface of the tooth, it changes colour in response to the pH of the mouth. The coloured indicator thus alerts the wearer to the requirement of replacing the dental plate.

In Figures 6 and 7, the tooth 20 includes a capping layer 24 disposed above the indicator 25 and forming a sandwiched disc structure 23 therewith. The capping layer masks the indicator until the tooth, and the capping layer itself, have been worn beyond the predetermined threshold. The capping layer lies approximately flush the end surface of the unworn tooth, and is visible at this surface. As the tooth is eroded, the end surface of disc 24 is concomitantly worn away and, beyond the predetermined threshold of wear, the second disc 25, which is visually distinct from the capping layer and the surrounding parts of the tooth, becomes exposed. The wearer is thus alerted to replace the dental plate when this indicator becomes visible.

Claims

CLAIMS:

1. An artificial tooth for incorporation into a dental plate, the tooth having an indicator buried therein, which indicator is of a material providing a coloured appearance that is visually different from adjacent parts of the tooth, the indicator being positioned within the tooth so as to be exposed when the tooth is subject to a predetermined amount of wear, thereby providing a visual indicator of that wear.

2. A tooth according to claim 1 further having a capping layer, the layer being of a material providing a coloured appearance which is different from both the indicator and adjacent parts of the tooth, the capping layer being disposed approximately flush to the wearing surface of the tooth and masking said indicator until both the tooth and the layer have been subject to said predetermined amount of wear.

3. A tooth according to claims 1 or 2 wherein the coloured appearance of the indicator changes in response to an agent in the mouth to which it becomes exposed after said predetermined amount of wear, the modified appearance of the indicator providing a visual difference from adjacent parts of the tooth.

4. A tooth according to claim 3 wherein the indicator is pH-responsive.

5. An artificial tooth substantially as herein described with reference to and as illustrated in, Figs.

1 to 3, or Figs. 4 and 5 or Figs 6A, 6B and 7 of the accompanying drawings.

6. A dental plate having at least one artificial tooth according to any one of the preceding claims.]

7. A dental plate according to claim 6 wherein at least one pair of said teeth having an indicator buried therein are disposed symmetrically in said plate.

S. A method of detecting the requirement to replace a dental plate, including the steps of: (i) burying an indicator in an artificial tooth, which indicator is of a material providing a coloured appearance that is visually different from adjacent parts of the tooth, the indicator being positioned within the tooth so as to be exposed when the tooth is subject to a predetermined amount of wear, thereby providing a visual indicator of that wear; (ii) constructing a dental plate to include at least one said tooth having an indicator buried therein; and (iii)monitoring the at least one said tooth to detect the exposure of the indicator.

9. A method of detecting the requirement to replace a dental plate substantially as any herein described with reference to the accompanying drawings.