WO1997033529A1

WO1997033529A1 - Dental appliances and instruments

Info

Publication number: WO1997033529A1
Application number: PCT/AU1997/000149
Authority: WO
Inventors: Frank Hunter
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-03-12
Filing date: 1997-03-11
Publication date: 1997-09-18
Anticipated expiration: 1998-09-12
Also published as: AUPN863496A0; AU2087497A

Abstract

A clinical appliance for application to a tissue or a tissue-associated material, the appliance comprising a head (12), a handle (10), a pressure-sensitive means through which the head is moveable relative to the handle, an instrument adapted to be retained in the head, and an engageable locking means (30) adapted to maintain the head in fixed relationship to the handle. An instrument adapted for use with the clinical appliance comprising a rigid, curved, flexible or deformable member having a width of less than about 1 mm.

Description

Dental Appliances and Instruments

Technical Field

The present invention relates generally to improvements to appliances and instruments for the diagnosis, treatment and therapy relating to the oral cavity and in particular appliances and instruments for the treatment and therapy of periodontal disease. Background Art

Periodontal disease is now recognised as amongst the most prevalent oral diseases throughout the world today. It has, therefore, become one of the most important diseases within the practice of modern dentistry worldwide. Recent research has demonstrated that periodontal disease is destructive by being a major cause of adult tooth loss. It is endemic as it affects people irrespective of their age, race, sex, nationality and socioeconomic status. The disease is progressive whereby the initial lesion may remain static, be quiescent, transient or progress through defined stages of tissue destruction towards final tooth loss. It is episodic as it may commence without symptoms or awareness and progress through episodes of active tissue destruction at various rates and degrees. It may be site specific and affect only localised sites on any tooth or any number of teeth in any mouth at varying degrees of severity. It is inflammatory by being a host tissue response to foreign matter (plaque) and it is infectious as it is caused by a variety of pathogenic microorganisms. It is non-discriminatory as it may affect people who otherwise appear quite healthy and so may go undetected without proper professional screening. It is developmental and has been classified into five levels of activity: 0 (no sign of symptoms), through 1, 2, 3 and 4 (severe advanced disease). Importantly, periodontal disease is preventable from occurring by professional guidance and preventative measures such as plaque control. The disease is identifiable as the initial lesion may be detected and each subsequent stage of activity identified using a proper screening programme. The disease is treatable as it may be intercepted, the cause removed and thereby reduced as an active disease process. It is controllable by appropriate attention by trained healthcare professionals who can control the destructive disease process and finally, periodontal disease is exclusive as it is the prime responsibility of the oral health profession to prevent, detect, identify and treat this disease. A universal standard called True Periodontal Score (TPS) was developed by the present inventor in cooperation with the World Health Organisation (WHO) and Federation Dentaire Internationale (FDI) for use by all dental clinicians in the examination of soft tissue as a necessary requirement of every routine oral examination. TPS provides a simple integrated system of screening, detection, measurement, classification, diagnosis and management of periodontal disease in dental practice. The programme includes basic information regarding periodontal disease, a current knowledge update, a simple five code classification, a sextant recording chart, a universal standardised probe and a guide to essential minimum standards of professional healthcare necessaiy to provide optimum quality of care to the patient.

An important part of the TPS standard is the use of a periodontal probe as the basic appliance used to measure clinical features such as pocket depth, level of attachment, bleeding response, furcation involvement and to detect aetiological factors such as calculus, defective restoration margins, root erosion, root caries and other plaque retentive features. There are many different probes available which vary in size, shape and type and these give different readings together with operator variables to provide data which is not reliable, comparable, consistent, repeatable or reproducible. In order to address this problem, a new probe and clinical appliances have been developed as a refinement of the original WHO probe. Examples of these probes can be found in US Patent Nos 5137447 and 5322437, which are incorporated herein by reference. These new probes/appliances offer a simple pressure sensitive force control mechanism for pressure up to and around 20 gm. In one form, a probe comes with a disposable head to control infection transfer risk and a flexible tip to more safely explore furcations, bent roots and tilted teeth. It has a modified 0.5 mm ball tip to better detect calculus and defective margins and a broad band at 3.5 - 5.5 mm zone for screening purposes, but also has finer millimetre markings which are necessary in more detailed measurements within complete periodontal examinations (screening codes 3 and 4), monitoring of treatment response and regular surveillance checks.

TPS has been a major development in dental examination, however, the present methods of treatment still involve aggressive procedures using comparatively large instruments that are prone to cause further damage to the areas around the oral cavity when used. Appliances and instruments used to treat periodontal disease including build-up of dental calculus are usually large (greater than 1 mm in width) and sharp instruments used to chip and scrape away this hard material. In using such appliances and instruments there is often further damage caused to the surrounding tissues. Furthermore, many different appliances are needed and used to diagnose and then treat periodontal disease. A pressure-sensitive probe is initially used to diagnose disease in a manner that is accurate but sensitive to the surrounding dental tissues. In current practices this is often followed by an aggressive, often inaccurate means of treatment using different appliances and instruments that are not sensitive in use to the area of treatment. Many appliances and instruments are needed to diagnose and then treat periodontal disease under present practices.

In order to attempt to address this serious shortcoming in dental treatment, the present inventor has developed dental appliances and instruments more suitable for the treatment of disease and in particular for the treatment of periodontal disease. Disclosure of Invention

The present invention provides instruments that have the distinct advantage of being adaptable for use in several applications on the same patient.

In a first aspect, the present invention consists in a clinical appliance for application to a tissue or a tissue-associated material, the appliance comprising a head, a handle, a pressure sensitive means through which the head is moveable relative to the handle, an instrument adapted to be retained in the head, and an engageable locking means adapted to maintain the head in fixed relationship to the handle.

Preferably, the locking means is adapted to prevent the movement of the head relative to the handle through the pressure sensitive means. In a preferred embodiment, the present invention consists in a clinical appliance for application to a tissue or a tissue-associated material, the appliance comprising a head, a handle, a pressure sensitive means through which the head is moveable relative to the handle, an instrument adapted to be retained in the head, and an engageable locking means adapted to maintain the head in fixed relationship to the handle, wherein the head and handle each having disposed thereon a mark which when no force is exerted on the instrument are out of alignment, but when a selected force is exerted will be aligned.

In one embodiment, the pressure sensitive means comprises a resiliently deformable member. The attachment of the head to the handle may be by the resiliently deformable member. Alternatively, the resiliently deformable member may form part of the head and is retained in the handle by an attachment means.

The locking means may be in the form of a sliding collar, a cap arrangement, spacer arrangement adapted to be accommodated in or on the pressure sensitive means, or any other locking means known to the art that will prevent the pressure sensitive means from functioning.

In a further preferred embodiment of the first aspect of the present invention, the head is integrally formed with the pressure sensitive means in a manner such that the head is capable of being removably attached to the handle. In the form where the pressure sensitive means comprises attachment of the head and the handle by a resiliently deformable member, the head is integrally formed with the resiliently deformable member in a manner such that the head is capable of being removably attached to the handle. In another form of the appliance according to the present invention, the locking means may be in the form of an attachment that replaces the pressure sensitive means. In this form, the head including the pressure sensitive means is removed from the handle and replaced with a new head including the locking means such that in use the head is no longer moveable relative to the handle.

In one embodiment the appliance is disposable and in another embodiment the appliance is made of material suitable for sterilisation and re-use.

When the appliance is to be used as a diagnostic periodontal tool, for example, the locking means is disengaged and the head is moveable relative to the handle through the pressure sensitive means. By engaging the locking means, the same appliance can then be used for treatment, for example as a scraping tool. Furthermore, the instrument can be replaced in the appliance to provide further treatment and/or diagnosis without the need to have a number of different appliances at hand to provide diagnosis and treatment of the same patient. In a second aspect, the present invention consists in an instrument adapted for use with the clinical appliance according to the first aspect of the present invention comprising a rigid, curved, flexible or deformable member having a width of less than about 1 mm. Preferably, the width of the member is about 0.5 mm. The instrument is preferably calibrated with increment markings along its length to indicate depth.

In a further preferred embodiment of the second aspect of the present invention, the instrument further comprises an abrasive material placed thereon. The abrasive material may be comprised of diamond dust, silica, aluminium oxide or any other suitable abrasive material. The abrasive material may be placed circumferentially, placed on one side forming partial cover or completely over the full length of the instrument. When the instrument is adapted for scaling of dental calculus the abrasive material is preferably less than 1,000 microns. When the instrument is adapted for planing of dental calculus, the abrasive material is preferably greater than 10 microns.

The instruments may have any defined shape such as a rim ledge, hook, file, teeth or any combination thereof to effectively engage in adhesions, protrusions, intrusions or any other such root surface or phenomena found in clinical dentistry. In a preferred form, the instrument has a tapered or straight shaft.

The instrument may be used by hand motion by the operator or driven electrically or mechanically by vibratory, ultrasonic or any other form of assisted movement. The instrument may be preformed in various shapes or may be formable by the user to suit the given application. The instrument may further include sampling, measurement or diagnostic means and may contain a means for application of medicaments, tissue or tissue associated material to the site of treatment. The instrument may further comprise means for illumination, audio and/or visual monitoring means or means for tissue sampling known to the art.

In order that the invention may be more clearly understood preferred forms will be described with reference to the following examples and drawings. Brief Description of Drawings

Figure 1 shows in side view an example of a form of a dental probe from US Patent No 5137447;

Figure 2 is a perspective view of a clinical appliance from US Patent No 5322437;

Figure 3 shows an example of a locking means in the form of a cap adapted for use with the clinical appliance of Figure 2;

Figure 4 shows an example of a locking means in a form of a spacer arrangement adapted for use with the probe and appliance of Figures 1 and 2, respectively;

Figure 5 shows an example of a locking means in the form of a sliding collar adapted for use with the appliance of Figure 2; and

Figure 6 shows example of a head adapted to be mounted without a resiliently deformable member in a handle of the appliance of Figure 2. Modes for Carrying Out the Invention

With the development of new probes and clinical appliances adapted for use as clinical measuring instruments or gauges and sampling devices, there is a need to further utilise this technology in the treatment of disease, particularly periodontal disease. TPS has made great advances in the diagnosis of periodontal disease and further developments are needed to translate these same standards of dimension, size, shape and form and so adopt this programme to the treatment of diseases so diagnosed. Figures 1 and 2 show examples of appliances suitable for examination of tissue using TPS but instruments presently available for treatment of periodontal disease have different standards and thus are prone to cause further damage to dental tissues during use. There is a need to provide an appliance that is suitable for the diagnosis of periodontal disease and then adaptable to be used for the effective treatment of the diagnosed disease. The present inventor has developed clinical appliances that have a pressure sensitive means and further comprising a locking means adapted to prevent the operation of the pressure sensitive means allowing the same appliance to be used for treatment by utilising new instruments adapted for use with the appliance.

One example of a locking means for the appliance of Figure 2 is shown in Figure 3. The appliance 10 comprises a removably attachable resiliently deformable member 12 and head 13, substantially as described with reference to Figures 1, 3, 4 and 5 of US Patent No 5322437. The locking means is in the form of a cap 30 having a cavity 31 that is adapted to receive the head 13 of the appliance 10. The cap 30 has slots 32 placed therein adapted to receive the protrusions 20, 21 on the handle 11 and head 13 respectively of the appliance 10. The cap 30 also has a slot 33 positioned so as to pass around the instrument 14 of the head 13. When placed over the end of the appliance 10 the locking means thereby prevents the deformable member 12 from moving within the spaced apart plates 18. The cap 30 may comprise additionally a light or any other component that may be suitable in the use of the appliance in diagnosis and treatment of periodontal disease. Another example of a locking means for the appliance of US Patent

5322437 is shown in Figure 4. The locking means comprises an insert 40 that is adapted to fit within the cavity 29 of the resiliently deformable member 12 so as to prevent the thin parallel plates 15 from movement when pressure is placed on the instrument 14. In a further embodiment, the locking means may be attached permanently to the member 12 as shown in Figure 6.

A further example of a suitable locking means for the appliance of Figure 2 is shown in Figure 5. The locking means comprises a sliding collar arrangement 50 having a cavity 51 that is adapted to slide over the handle 11 thereby fixing the deformable member 12 within the plates 18 of the handle 11 and preventing the pressure sensitive means from operating. The collar arrangement 50 has recesses 52 placed therein adapted to receive the protrusions 20, 21 on the handle 11 and head 12, respectively, thereby preventing relative movement of the head 12 and handle 11.

Another form of a collar arrangement does not have recesses to accommodate protrusions 20, 21 but clips over the resiliently deformable member 12 to arrest any movement thereof.

It will be appreciated that other locking means would also be suitable to ensure that any pressure sensitive means of any form of probe or appliance is no longer operable on the probe or appliance when in use. The clinical appliance according to the present invention may be disposable or made of materials suitable for sterilisation and reuse.

Existing instruments on appliances have various dimensions, are formed with preset bends and shape, have no depth markings and are often sharp surgical cutting or scraping instruments that may cause significant damage to surrounding tissue when used. The present inventor has developed suitable instruments in order to address the shortcomings of the instruments presently used on appliances currently used in dental treatment.

The present invention also relates to new instruments preferably in the form of tips for clinical appliances. The new instruments are particularly suitable for the appliances of the present invention. The tips may have various dimensions and size but ideally should be about 1 mm or less thick and more preferably having a thickness of approximately 0.5 mm. The tips are so formed to be suitable as a means of treatment by scaling to achieve gross debridement of dental calculus, planing to smooth out root surfaces and as a means to prepare reattachment of oral tissue and biological repair.

In order to more responsibly treat the wide range of periodontal diseases, it is necessary to remove the many forms of known causative agents of periodontal disease, namely the plaque retentive features such as calculus, defective restoration margins, root caries, root erosion and other such anomalies causing root surface roughness. It is equally paramount, however, to reduce the risk of damage being caused to the tooth root surface and other tissue by aggressive and uncontrolled attack using instruments of varying size, shape and form.

An advantage of the present invention is that it primarily reduces the risk of tissue damage by first standardising the size, shape and form of instrument used in the treatment phases. Furthermore, the present invention provides sufficient scope to efficiently cater for treatment modalities under the many different conditions that prevail within the mouth in the real clinical situation. To this end, there needs to be a range of tips available which cater for the two basic stages of root treatment. The first stage is described as "primary debridement" or commonly referred to as primary scaling, whereby gross amounts of defects or adhesions are removed quickly and, in some cases, rather aggressively. The second phase of treatment is the "secondary debridement" or root planing, where the tooth root surface is smoothed to remove roughness, which is often created in the primary or preceding treatment phase. This secondary smoothing or root planing is a more gentle procedure and is necessary to prepare the tooth root surface to first be less plaque retentive and to take the form of a more smooth and suitable site onto which periodontal tissue may attach or re-attach. Since this is the ultimate goal of periodontal therapy, it is critical to prepare the tooth root surface to be left in the best possible state for this to occur i.e. as smooth and/or as clean as possible.

Aetiological factors such as calculus, defective restoration margins, root erosion, root caries and other forms of surface roughness may occur in varying forms of integrity and hardness and therefore may pose difficulty of removal. There must therefore be range of instruments available which provide, firstly, a "SAFE" excursion around tissue to minimise damage, secondly, an "EFFICIENT" and expeditious removal of foreign matter and, thirdly, the facility to "SMOOTH" out any roughness so created by surgical debridement. These three features are not well catered for in the current range of instrumentation.

The instruments of the present invention in the form of tips entertain credible standards of dimension having a preferred diameter of no greater than 1 mm and more preferably about 0.5 mm. The tips may have measurement marks to indicate the depth of operation. Ideally, these should be in zones in the form of bands at 0 - 3.5 mm, 3.5 - 5.5 mm and 8.5 mm at least. Further it is an advantage to have millimetre marks superimposed within these broad zones. This facility allows the operator to frequently check the depth of operation and to relate this back to the measurements taken at the examination phase. This reduces the risk of damaging tissue by working too deeply.

The tips may be made of a semi-flexible or malleable material so that they can be shaped to best fit around any particular site of operation. Many "soft" metals and alloys offer this facility and this form of tips may or may not have the depth marks on it. Alternatively, the tips may be more rigid, pre-formed and specially shaped to engage on very resistant adhesions or restoration margins and so minimise the risk of otherwise repetitious excursions. This form of tip may or may not have the depth marks on it.

Since adhesions on teeth present in many different forms of hardness and difficulty of removal there needs to be a range of tip forms to cater for expeditious removal. Within the scope of the present invention, the tips include for example a rim around the circumference of the tip, a hook at its base, a ledge of any kind, a file-type serration of either single or multiple 'teeth' or any other such defined shape that will effectively engage surface roughness and/or adhesions on the tooth root surface and expeditiously remove the roughness or adhesions when used appropriately. Another preferred form is to have a coating of abrasive material around either all or part of the tip. This material should be either of a defined or mixed particulate size, according to severity and form of adhesions challenging their removal. The range of particulate size is preferably no greater than 1000 microns and preferably having an average between 10 and 1000 microns in size. Various grades of abrasive materials have been found to be effective, according to individual cases, eg. 50 microns, 200 microns and 500 microns. Further this abrasive coating may be placed circumferentially on the entire tip, or it may partially cover tip surface. Similarly, it may be at any number of defined depths along the tip. e.g. from 0 - 3.5 mm depth, from 0 - 5.5 mm depth and from 0 - 8.5 mm depth and so on.

The present inventor has discovered that larger size particles (greater than 200 microns) are more effective in primary debridement and scaling procedures and that finer particles are more effective in secondary debridements, root planing and root smoothing procedures. The materials used in this abrasive coating can vaiy from diamond, silica, aluminium oxide or any other form of abrasive material known to the art

The tips may have any defined shape such as a rim, ledge, hook, file, teeth, protrusion, indentation, or any combination of these to effectively engage on adhesions, protrusions, intrusions or any other such root surface roughness or phenomena found in clinical dentistry. They may, similarly, be of a semi-flexible, malleable or rigid pre-formed shape and may also have a coating of abrasive on the surface as well. This describes any combination of forms which may be necessary to engage and remove foreign matter or plaque retentive agents from teeth or surrounding tissue. Since there is a vast range of conditions that may exist clinically, there should be a selection of instrument tips available for appropriate treatment.

The instrument may be used by manual operation, be driven by some electrical or mechanical means such as vibration, ultrasonics or any other appropriate means, or it can be operated as a combination of manual and mechanical forms suitable for utilising either or both the primary and secondary debridement preparation features and the abrasiveness of the tips, either in separate episodes, in combination, or in succession. A further advantage of the present invention is that it allows a clinical appliance to be used as a diagnostic tool by disengaging the locking means so that the pressure sensitive means is activated and the instrument may be used to confirm the detection of the problem area in the dental cavity and ensure the optimum treatment.

When the appliance is in two parts comprising a handle 11 and deformable member 12, different members 12 having various instruments in the form of different tips may be inserted in the handle 11 for use during treatment. The one appliance may be used to diagnose disease utilising the pressure sensitive means and then be suitable to treat the disease by engaging the locking means and optionally adding different instruments to the appliance as required during treatment. A facility exists to remove the locking means at any time during treatment and to re-engage the force control mechanism if that is desired or necessary to check during the treatment procedure. Once checked and ascertained, the locking means may be re-applied and treatment continued with the rigid versions. The present inventor has been involved with much of the research and development of the TPS system of examination and the instruments described in US Patent Nos. 5137447 and 5322437. The inventor is aware of the immense improvements that use of those instruments which entertain proven standards of dimensional size shape and force control make over conventional instruments towards the more accurate detection, measurement and assessment of periodontal disease. Ultimately, the present inventor has translated those same features of dimensional standards into a form that may be used for treatment of periodontal disease. Furthermore, the present inventor has realised the advantage that exists in using the same dimensions of size, shape and form in treatment instruments that are available in examination instruments. The present invention allows treatment of periodontal disease more intimately and directly with the known standards used within the examination procedures which precede that treatment. The advantage now exists that the same data of measurement taken at the examination may be used in the treatment modalities of the same lesion.

Treatment will be a more proven, controllable, universal, reliable, documentable and defensible exercise using the present inventions. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:

1. A clinical appliance for application to a tissue or a tissue-associated material, the appliance comprising a head, a handle, a pressure sensitive means through which the head is moveable relative to the handle, an instrument adapted to be retained in the head, and an engageable locking means adapted to maintain the head in fixed relationship to the handle.

2. A clinical appliance according to claim 1 in which the locking means is adapted to prevent the movement of the head relative to the handle through the pressure sensitive means.

3. A clinical appliance according to claim 1 or 2 wherein the head and handle each having disposed thereon a mark which when no force is exerted on the instrument are out of alignment, but when a selected force is exerted will be aligned.

4. A clinical appliance according to any one of claims 1 to 3 in which the pressure sensitive means comprises resiliently deformable member.

5. A clinical appliance according to claim 4 in which the attachment of the head and the handle is by the resiliently deformable member.

6. A clinical appliance according to any one of claims 1 to 5 in which the locking means being in the form of a sliding collar, a cap arrangement, or spacer arrangement adapted to be accommodated in or on the pressure sensitive means such that when the locking means is engaged the pressure sensitive means is prevented from functioning.

7. A clinical appliance according to any one of claims 1 to 6 in which the head being integrally formed with the pressure sensitive means in a manner such that the head is capable of being removably attached to the handle.

8. A clinical appliance according to any one of claims 1 to 7 in which the pressure sensitive means is removed and replaced by the locking means in order to prevent the movement of the head relative to the handle.

9. An instrument adapted for use with the clinical appliance according to any one of claims 1 to 8 comprising a rigid, curved, flexible or deformable member having a width of less than about 1 mm.

10. An instrument according to claim 9 in which the width of the member is about 0.5 mm.

11. An instrument according to claim 9 or 10 being calibrated with increment markings along its length to indicate depth.

12. An instrument according to any one of claims 9 to 11 further comprising an abrasive material placed thereon.

13. An instrument according to claim 12 wherein the abrasive material is selected from the group consisting of diamond dust, silica, aluminium oxide, and mixtures thereof.

14. An instrument according to claim 13 adapted for scaling of dental calculus wherein the abrasive material is preferably less than 1,000 microns.

15. An instrument according to claim 13 adapted for planing of dental calculus wherein the abrasive material is preferably greater than 10 microns.

16. An instrument according to any one of claims 9 to 15 having a shape selected from the group consisting of a rim, ledge, hook, file, teeth, protrusion, indentation, and any combination thereof to effectively engage adhesions, protrusions, intrusions or any other tooth root surface or phenomena.