WO1998022025A1

WO1998022025A1 - Application to determine the risk of tooth decay and a test device especially suited thereto

Info

Publication number: WO1998022025A1
Application number: PCT/EP1997/006214
Authority: WO
Inventors: Claus-Jürgen MÖLL; Theodor Paessens
Original assignee: M & M Dental-Medizin Gmbh
Priority date: 1996-11-16
Filing date: 1997-11-08
Publication date: 1998-05-28
Also published as: DE19647545A1; AU5480198A; EP0952787A1

Abstract

In order to apply a sterile absorbent material with a solid, predetermined uptake quality and a sterile transport medium so that the risk of tooth decay can be determined in a test person with the utmost accuracy yet at low cost and with ease of use, the invention suggests that a) the test person should rub the surface of the oral cavity directly with the absorbent material after a night's rest, b) put the absorbent material into a nutrient solution, whereby c) the species and/or number of microorganisms found in the absorbent material is determined and the risk of tooth decay is established using the results obtained.

Description

Use to determine the risk of caries and especially suitable test equipment

The invention relates to the use of an absorbent material and a transport medium for determining the risk of caries in a subject. The method is particularly applicable to humans, but use in animals is also possible.

To prevent caries, regular check-ups at the dentist are required. A six-monthly rhythm is generally recommended. However, this recommendation is often not followed, since the medical layperson (patient) does not know his personal risk of caries and often mistakenly believes that this risk is low for himself.

WO 96/18902 AI describes a possibility for the layperson to obtain information about his personal caries risk in a simple, fast, convenient and inexpensive manner. To perform the test, the subject inserts a carrier with an absorbent material into his mouth. The absorbent material, which consists in particular of dry medical cotton wool, is coated with a coating that stimulates the metabolism of the microorganisms in the oral cavity. As a result, the pH drops. After the coating has dissolved, the saliva or at least part of the saliva is absorbed by the absorbent material. To determine the risk of caries, the subject briefly rolls the damp absorbent material back and forth on a test strip until the strip changes color. The pH value and thus the risk of caries, which is particularly high at a low pH value, can be read by comparing the discoloration with a color scale arranged next to the test strip.

The known method allows a general statement about the risk of caries, but an indication of the type and number of microorganisms in the oral cavity and thus the specific causes of the risk of caries would be desirable. worth it because the individual types of microorganisms have a different function in the development of caries.

In many cases, the exact diagnosis and selection of the right therapeutic agents depend on determining the pathogen and determining the medication that is effective against it. The targeted use of a particularly effective remedy against the respective pathogen is sought by medical science today, since this is the least stressful for the patient and the best way to ensure the healing success. The increasing development of resistance of bacteria to broadly used broad-spectrum antibiotics in many cases makes this measure compulsory.

Since most dental surgeries are not equipped for bacteriological examinations and the examinations may not be carried out for hygiene reasons, bacteriological examinations should be carried out in special laboratories. The quality of the bacteriological tests is decisively influenced by the quality of the material that is made available to the laboratory for the test. In addition to errors in sampling, the transport of the test material in particular has proven to be a significant weak point. Except for very short transport times, the pathogens must therefore be protected against drying out and oxidation damage using a suitable transport medium. Drying out is usually achieved by embedding in a suitable semi-solid agar medium and oxidation damage by means of a protective gas containing nitrogen or carbon dioxide, so that the pathogens at

Storage at usual temperatures between 6 and 20 ° C are still fully usable after 6 to 12 months.

Saliva tests and tools for removing saliva for analysis purposes have long been known. Such a method is described for example in DE 36 32 303 AI. Here is an elastic, absorbent, inert body chewed by the test subject and then placed in a centrifuge tube provided with a perforated bottom.

However, like many other known methods, the method is only carried out in dental practice. It must be ensured that, apart from the microorganisms of the oral cavity, no other germs get on the elastic body.

EP 0 418 739 AI describes a device for removing saliva from the oral cavity. The device consists of an absorbent material, a pad, which is clamped in a groove in a plastic stick. To remove the saliva, take the stick and insert the pad attached to it into the oral cavity. After the pad has absorbed a sufficient amount of saliva, it can be stored in a container until the test is carried out.

The container consists of a centrifuge tube into which an inner tube is inserted. In order to insert the pad into the container without contamination with foreign germs, an additional aid is required, which consists of a plate with an opening for the plastic stick. After removing the container closure and inserting the pad into the inner tube of the container, the plate with its opening is placed over the opposite end of the plastic rod until the plate rests on the opening edge of the container. When the plastic stick is withdrawn from the container, the pad is removed from the

Retain platelets and remove them from the stick this way. A liquid is then added, which prevents the analysis result from being falsified even when the sample is stored for a long time, and the closure cap is placed on the container.

This relatively cumbersome procedure is not suitable for the use of a layperson without dental help, especially since When inserting the pad into the container, it must always be ensured that there is no contamination with foreign germs.

For another, particularly important reason, the use of this known method for determining the risk of caries is less suitable. A saliva sample taken during a dental examination has two major disadvantages. The relatively large saliva production over the course of a day, which is around 20 ml per hour, leads to a relatively low concentration of the microorganisms in the oral cavity compared to the night's sleep during the 7th due to the antibacterial activity of the saliva and the relatively high amount of saliva Hours a total of only 20 ml of saliva can be produced. Although the growth rate for plaque is reduced at night, it can be concluded from this information that the destructive effects of cariogenic microorganisms are particularly pronounced during sleep and that their concentration in the oral cavity is highest immediately after sleep.

To determine the risk of caries, it is therefore less the saliva that was extracted during the course of the day that is of particular interest. It would therefore be beneficial if the test person took out his saliva without any dental cooperation and preserved the microorganisms contained therein until the sample was analyzed microbiologically. The known methods for collecting and analyzing saliva do not meet these requirements.

The known methods either require the assistance of a medical specialist, since the one method is too cumbersome and complicated for a layperson and is therefore only suitable for analyzing saliva extracted in medical practice. As has already been stated, however, a precise analysis of the saliva taken immediately after the subject's night's sleep is particularly desirable. The other known methods only show the application of certain microorganisms or their metabolic products, but do not provide any information about the number of different microorganisms.

Further test methods and test devices for saliva are known from WO 92/16842 AI and WO 95/02822 AI. Here, however, the saliva is not removed immediately after the subject's night's sleep, and the test facilities have no transport medium to store the saliva for a long time until it is analyzed.

The test device known from WO 95/27205 AI has a test stick with a predetermined breaking point so that the handle part can be removed after the saliva has been removed.

Finally, further systems for collecting saliva samples are described in WO 95/02996 AI and WO 95/30484 AI. However, these are relatively complicated and complex systems which also contain no transport medium to preserve the saliva sample until a later analysis. The absorbent material used here also has no specific, predetermined absorption capacity for saliva.

The invention is therefore based on the object of developing a simple and inexpensive possibility for determining the risk of dental caries and its causes in a considerably more precise manner.

This object is achieved according to the invention by the use of a sterile absorbent material with a fixed, predetermined absorption capacity and a sterile transport medium for determining the risk of caries in a test subject, with a) the subject immediately after the night's sleep with the absorbent material over the surface strokes his oral cavity, especially over the palate, cheek pockets and tooth surfaces, b) the absorbent material is added to the transport medium, and c) the type and / or number of the microorganisms located on / in the absorbent material is determined and the caries risk is determined with the aid of the results obtained.

A few hours after taking the sample, the test person can hand over the transport medium with the absorbent material used to his dentist, who either analyzes the sample himself or forwards it to a laboratory. The transport medium enables an analysis of the type and number of microorganisms in the test person's oral cavity without the number of microorganisms and the relative frequency of the different species during the period, which usually lasts several hours, between taking the sample early in the morning and the microbiological determination changes. It is expressly emphasized that the transport medium mentioned is not a nutrient medium, because a significant change in the number of bacteria, which is typical for nutrient media, must not occur.

In the test method according to the invention, it is possible to determine the type and concentration of the microorganisms in the oral cavity without the test result being falsified by the presence of fresh saliva. In the prior art, however, such an examination can only be carried out by the dentist taking plaque from the interdental space and having it examined. In addition to the more complex step for sampling, the known method has the disadvantage that the microbiological conditions are only examined at a specific point in the mouth. In contrast, the method according to the invention enables these conditions to be detected in the entire oral cavity without interference from fresh saliva flow.

The analysis can be carried out using known microbiological methods. A microbiological laboratory determines the type and / or number of materials on / in the absorbent material microorganisms and the results obtained determine the risk of caries.

The firm, predetermined absorption capacity of the absorbent material for the saliva of the test subject is important in the method according to the invention. For this purpose, it is proposed that 0.8 to 1.2 ml of saliva be absorbed by the absorbent material when the surface of the oral cavity is swept over. This value is in particular exactly 1 ml, which is absorbed by the absorbent material in a period of about 2 minutes.

The subject preferably dissolves a substance that stimulates the metabolism of the microorganisms of the oral cavity, in particular a sugar-like substance or other carbohydrates, or a corresponding composition of substances in his oral cavity before he strokes the absorbent material over the surface of his oral cavity, the substance or the said composition of substances is selected so that he / she does not influence the flow of saliva, so that the microorganisms are not disturbed by the antibacterial activity of the fresh saliva.

A preferred composition of substances of this type and a preferred composition for the sterile transport medium can be found further below in the description.

The invention also relates to a test device for sampling, which is particularly suitable for carrying out the method according to the invention, for determining the risk of caries in a human or animal subject, with a sterile-packed elongated carrier which has a sterile absorbent material, in particular dry medical cotton wool, at one end , wearing. In particular, the absorbent material consists of cotton.

The above-mentioned object is achieved in this test device according to the invention by a reclosable container which contains a sterile transport medium. holds and is suitable for receiving the carrier with the absorbent material, the other end of the carrier being designed as a grip part which, after the container containing the carrier and the absorbent material has been closed, is located outside the container.

Contamination of the saliva contained in the absorbent material with foreign germs during sampling is avoided by the carrier mentioned, since the medical layperson is not tempted to touch the absorbent material with his hands. To remove the absorbent material from his mouth, the subject will rather grasp the carrier by the handle part, which cannot come into contact with the transport medium. The suitability of the reclosable container for holding the carrier is important for convenient and quick introduction of the sample from the oral cavity into the transport medium. In contrast to the prior art, sterile aids for stripping the absorbent material from the carrier are not necessary according to the invention. In this way, contamination of the sample between removal from the oral cavity and introduction into the transport medium is avoided even by the untrained layperson during the sampling, without special additional measures being necessary.

It is also proposed that the container contains a sponge which is impregnated with the transport medium and on which the absorbent material rests when the carrier is introduced into the container. Damage to the surface of the absorbent material by immersing the carrier in a viscous transport medium and detaching individual material particles with adhering microorganisms from the carrier, which could possibly falsify the laboratory result, does not occur in this case with certainty.

An exact, reproducible statement about the concentration of the different types of microorganisms in the oral cavity is achieved in that the absorbent material has certain, predetermined absorption capacity for saliva, which is in particular 0.8 to 1.2 ml of saliva with an absorption period of about 2 minutes.

In a particularly preferred embodiment of the invention, the handle part of the carrier is designed as a closure cap for the reclosable container. To introduce the sample into the transport medium, it is therefore only necessary for the test person to open the container for the transport medium and to insert the carrier with the absorbent material into this container. Since it only touches the cap and thus avoids contact with the absorbent material and with the other parts of the carrier, there is a high level of security against contamination of the sample with foreign germs.

Because the carrier with the sterile absorbent material must also be sterile packed before use, it is preferred if the carrier with the absorbent material is packaged in a second container, this container being tightly sealed by the said cap.

In a further embodiment of the invention, the subject, who can be a layperson with a wide variety of skills and training, is relieved of the necessity, even with very clumsy handling, of the parts of the carrier that come into contact with the transport medium or the inside touch the container with your hands. For this purpose, it is provided that the closure cap protrudes from the container opening when the container is closed.

There is sufficient contact surface for the subject's fingers to remove and put on the closure when the closure cap protrudes at least 5 mm from the container opening. With the proposed design of the closure cap attached to the carrier, it is achieved that only the part located outside when the container is closed is contaminated with foreign germs. The entire absorbent material and all parts of the carrier and the closure cap, which are located within the container with the transport medium, have no contact with foreign germs during the transfer from the oral cavity into the transport medium, without any special skill of the test person or an auxiliary position during this Operation must be assumed.

Known, suitable gel-like or liquid compositions suitable for this purpose can be used as the transport medium. The transport medium for microorganisms is preferably intended and suitable for gram-negative, gram-positive and anaerobic bacteria.

In addition to water, the transport medium in particular contains 0.01 to 0.1% by weight K ₂ HP0 ₄ , 0.01 to 0.1% by weight KH ₂ P0 ₄ ,

0.05 to 0.1% by weight NaCl,

0.05 to 0.1% by weight (NH ₄ ) ₂ S04,

0.01 to 0.02% by weight of MgS0 ₄ ,

0.01 to 0.05% by weight of Na ₂ CO ₃ and 0.01 to 0.03% by weight of dithiothreitol.

The mixture preferably has a pH of 7.3 ± 0.1 at 25 ° C.

Depending on the intended purpose, the mixture can still be a

Redox indicator can be added, such as methylene blue or resaminin, which shows through its discoloration whether the transport medium contains oxygen. To the extent that only certain pathogens are to be investigated, the growth of the pathogens of no interest, which, if appropriate, can be achieved by adding selectively acting antimicrobial additives, such as vancomycin, kanamycin, nystatin or trimethoprim can be brought in as contamination by incorrect sampling.

The carrier is preferably coated with a mass which is soluble in saliva and which stimulates the metabolism of the microorganisms, in particular a sugar-like substance or other carbohydrates, and optionally also a sugar substitute, the mass being chosen such that it does not influence the flow of saliva. A starch content is particularly advantageous since it does not stimulate the flow of saliva. The addition causes a weak supply of nutrients, which obviously favors the persistence of the pathogens, but without initiating growth and thus propagation.

The mass is preferably designed as a covering for the absorbent material, the covering completely enclosing the absorbent material. The absorbent material only absorbs the saliva and the microorganisms present in the oral cavity when part of the coating or even the entire coating has dissolved and thus a certain waiting time has passed in which the microorganisms wait for the ingredients of the mass in the have responded as desired.

In order to make it easier for the test subject to adhere to the waiting time required for the reaction of the microorganisms, it is further proposed that the composition and amount of the mass have been selected such that, when the mass is completely dissolved by the saliva, the minimum time period for triggering the reaction of the microorganisms has passed. If the subject therefore determines that the mass has completely dissolved, the carrier can be removed and placed in the container with the transport medium.

It is further proposed that the composition and amount of the mass should be chosen so that it dissolves in the oral cavity for a period of 1 to 10 minutes, preferably 2 to 5 minutes. It is also advantageous if the layer (coating) consists of a mass which is composed essentially of the ingredient which stimulates the metabolism of the microorganisms and fat as a binder. Such a coating is to be applied to the absorbent material in a particularly economical manner in the mass production of the test device.

Alternatively, it is suggested that the mass be made of

17 to 45% by weight of glucose,

8 to 45% by weight of gelatin,

2 to 10% by weight of sucrose and

Starch consists of 0.2 to 0.3% by weight.

The mass is preferably designed as a coating for the absorbent material with a thickness of 0.1 to 0.5 mm, in particular 0.1 to 0.2 mm. This configuration ensures that a waiting time of 2 to 5 minutes has been observed after the coating has completely dissolved.

The acceptance of the test device by the consumer is improved if the mass also contains flavorings. The aromas of lemon, lime, peppermint and eucalyptus are examples.

An exemplary embodiment of the invention is explained in more detail below with the aid of a drawing, which shows a sterile packed carrier with the absorbent material in the reclosable container with a gel-like transport medium in longitudinal section.

A wooden test stick, the carrier 1, has a cotton ball 2, the absorbent material, at one end, the upper end in the figure. The medical cotton is coated with a neutral, pleasant-tasting mass 4 that does not promote saliva secretion. The test stick is inserted into a glass tube 5 after the saliva has been removed. A closure cap 6 with two ring-shaped sealing lips 7, one behind the other, formed on an inner sleeve 3, is connected to the end of the test stick 1, which lies opposite the cotton ball 2. The closure cap 6 protrudes about 10 mm beyond the opening 8 of the glass tube 5 to form a comfortable grip surface. The profiling of the outside of the gripping surface in the longitudinal direction, which is indicated by a few lines 9, makes it easier to remove and insert this closure cap 6 connected to the test stick 1, so that the stick 1 is not necessary or expedient for the user or touch the absorbent mass 2 with your hands or another object.

The resealable container 5 provided in the test device also contains a transport medium 10. Alternatively, a sponge soaked with the transport medium can be provided on the bottom of the container, on which the end of the

Test stick is on. The container 5 is secured with the closure cap 6 in an airtight and liquid-tight manner.

The transport medium is composed as follows: 0.045% by weight K ₂ HP0 ₄ ,

0.045% by weight KH ₂ P0 ₄ ,

0.09% by weight NaCl,

0.09% by weight (NH ₄ ) ₂ S0 ₄ ,

0.018% by weight MgS0 ₄ , 0.04% by weight Na ₂ C0 ₃ ,

0.02% by weight of dithiothreitol and the rest of water.

Claims

Patent claims

1. Use of a sterile absorbent material with a fixed, predetermined absorption capacity and a sterile transport medium for determining the risk of caries in a test person, wherein a) the test person immediately after sleeping with the absorbent material over the surface of his mouth , especially over the palate, cheek pockets and tooth surfaces, b) the absorbent material is added to the transport medium, and c) the type and / or number of microorganisms located on / in the absorbent material is determined and with

The caries risk is determined using the results obtained.

2. Use according to the preceding claim, d a d u r c h g e k e n n z e i c h n e t that 0.8 to 1.2 ml of saliva is absorbed by the absorbent material when sweeping over the surface of the oral cavity.

3. Use according to the preceding claim, so that said amount of saliva is absorbed by the absorbent material over a period of about 2 minutes.

4. Use according to one of the preceding claims, characterized in that the subject dissolves a substance which stimulates the metabolism of the microorganisms of the oral cavity, in particular a sugar-like substance or other carbohydrates, or a corresponding substance composition in his oral cavity before he dissolves with the absorbent material via the The surface of his oral cavity paints, the substance or composition mentioned above is chosen so that he / she does not influence the flow of saliva.

5. Test device for sampling to determine the risk of caries in a human or animal subject, particularly suitable for performing the method according to any one of the preceding claims, with a sterile packed elongate carrier (1) having a sterile absorbent material at one end (2), in particular dry medical cotton, characterized by a reclosable container (5) which contains a sterile transport medium (10) and is suitable for receiving the carrier (1) with the absorbent material (2), the other end of the Carrier is designed as a grip part, which is located outside the container after the container (5) containing the carrier and the absorbent material has been closed.

6. Test device according to the preceding claim, characterized in that the container (5) contains a sponge which is soaked with the transport medium (10) and on which in the container (10) inserted carrier (1) the absorbent material ( 2) rests.

7. Test device according to the preceding claim, that the absorbent material (2) has a certain, predetermined absorption capacity for saliva, which is in particular 0.8 to 1.2 ml of saliva with an absorption period of about 2 min.

8. Test device according to one of the preceding claims, characterized in that the handle part of the carrier (1) is designed as a closure cap (6) for the reclosable container (5).

9. Test device according to the preceding claim, that the carrier (1) with the absorbent material (2) is packed in a second container, this container being tightly sealed by the closure cap (6).

10. Test device according to claim 8 or 9, so that the closure cap (6) protrudes from the container opening when the container (5) is closed.

11. Test device according to the preceding claim, that the cap (6) protrudes at least 5 mm from the container opening.

12. Test device according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the transport medium in addition to water

0.01 to 0.1% by weight of K ₂ HP0 ₄ ,

0.01 to 0.1% by weight of KH ₂ P0 ₄ ,

0.05 to 0.1% by weight NaCl,

0.05 to 0.1% by weight (NH ₄ ) ₂ S0 ₄ , 0.01 to 0.02% by weight MgS0 ₄ ,

0.01 to 0.05% by weight of Na ₂ CO 3 and

Contains 0.01 to 0.03% by weight of dithiothreitol.

13. Test device according to one of the preceding claims, characterized in that the carrier (1) with a saliva-soluble, the metabolism of the microorganisms stimulating mass (4), in particular a sugar-like substance or other carbohydrates, and optionally additionally coated with a sugar substitute, wherein the mass (4) is chosen so that it does not affect the flow of saliva.

14. Test device according to claim 13, so that the mass (4) is designed as a covering for the absorbent material (2), the covering (4) completely enclosing the absorbent material (2).

15. Test device according to claim 13 or 14, d a d u r c h g e k e n n e e c h n e t that the composition and amount of the mass (4) has been selected so that the minimum time for triggering the reaction of the microorganisms has elapsed when the mass is completely dissolved by the saliva.

16. Test device according to the preceding claim, that the composition and amount of the mass (4) has been chosen such that it dissolves in the oral cavity for a period of 1 to 10 minutes, preferably 2 to 5 minutes, so that it dissolves in the oral cavity.

17. Test device according to one of claims 13 to 16, d a d u r c h g e k e n n z e i c h n e t that the layer (4) consists of a mass which is composed essentially of the ingredient stimulating the metabolism of the microorganisms and fat as a binder.

18. Test device according to claim 16, d a d u r c h g e k e n n z e i c h n e t that the mass out

17 to 45% by weight of glucose,

8 to 45% by weight of gelatin,

2 to 10 wt .-% sucrose and 0.2 to 0.3 wt .-% starch.

19. Test device according to one of claims 14 to 18, characterized in that the mass is designed as a coating for the absorbent material with a thickness of 0.1 to 0.5 mm, in particular 0.1 to 0.2 mm.

20. Test device according to one of claims 13 to 19, d a d u r c h g e k e n n z e i c h n e t that the mass (4) additionally contains flavorings.