WO1996041587A1 - Improved apparatus for measuring sulfides within a periodontal pocket - Google Patents
Improved apparatus for measuring sulfides within a periodontal pocket Download PDFInfo
- Publication number
- WO1996041587A1 WO1996041587A1 PCT/US1996/007834 US9607834W WO9641587A1 WO 1996041587 A1 WO1996041587 A1 WO 1996041587A1 US 9607834 W US9607834 W US 9607834W WO 9641587 A1 WO9641587 A1 WO 9641587A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- probe
- fluid
- disposed
- sulcal
- reference electrode
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C19/00—Dental auxiliary appliances
- A61C19/04—Measuring instruments specially adapted for dentistry
- A61C19/043—Depth measuring of periodontal pockets; Probes therefor
Definitions
- This invention generally relates to the field of detecting gingivitis and periodontal disease and, more particularly, to an improved apparatus for measuring the concentration of sulfides within a periodontal pocket to determine the presence and extent of gingivitis and periodontal disease.
- Gingivitis and periodontal diseases are, broadly speaking, diseases which cause inflammation of the gum area surrounding a tooth. They are thought to be caused by the activity of Gram-negative anaerobic organisms. Early symptoms include redness of the gingival margin surrounding the tooth, slight edema or slight retractability of this margin, and slight or delayed bleeding on probing of the margin. If left unchecked, gingivitis and periodontal disease may cause further and severe retraction of the gingival margin, continuous and/or spontaneous bleeding, and even, eventual loss of the tooth due to the erosion of the supporting and investing structures surrounding the tooth, including the gums, cementum, periodontal membranes and alveolar bone, even though the tooth itself, may be perfectly healthy.
- gingivitis and periodontal disease are lost to gingivitis and periodontal disease than to disease and decay within the tooth, itself.
- gingivitis and periodontal disease enlarges the periodontal pocket or gingival sulcus of the affected tooth.
- the gingival sulci are the spaces or pockets between the gingival tissue (gums) and the teeth.
- Many experts in the field are of the belief that there is a correlation between the depth of a periodontal pocket and the severity of the disease. The depth of the periodontal pocket is usually measured from the margin or top of the gum to the epithelial attachment, the point where the gum attaches to the tooth. It is measured with a mechanical probe.
- the method used by Solis-Gaffar, et al. for determining the hydrogen sulfide generating potential of gingival crevicular fluid involved a chromatographic method; sterile filter paper strips were inserted into the crevice to collect the GCF.
- the analytic method disclosed is complicated, involving a three-day incubation of the strips with an appropriate amino-acid, and subsequent analysis with gas chromatography and a flame photometric detection system. Obviously, while useful for experimental purposes, the method disclosed in the Solis-Gaffar, et al. paper is not practical in a clinical setting.
- U.S. Patent No. 4,334,540 to Preti broadly teaches a method for the detection of pyridines in mouth saliva. The reference teaches collecting saliva samples, incubating the samples, and collecting the volatiles from the saliva from the head space above the saliva. Again, this is an indirect method for making a gross determination of whether a patient has or is developing periodontal disease.
- U.S. Patent No. 4,713,164 to Krietemeier discloses a method for analyzing malodors in the breath by means of a hand-held electrochemical detection means into which a sample gas stream is directed by blowing into the interior of the device.
- an electro-chemical sensor is inserted into the sulcus of the tooth to polarographically determine the ratio of at least two gases selected from the group consisting of oxygen, ammonia, hydrogen, methane, carbon dioxide and hydrogen sulfide in the crevicular fluid.
- the ratio measurements are correlated with known parameters to indicate the nature and presence or progression of periodontal disease.
- Patent No. 5,275,161 discloses a method and apparatus for electro-chemically detecting and quantifying sulfide levels in gingival sulci.
- the method employs a probe which is inserted into the sulcus and which includes miniature measuring and reference electrodes.
- the potential developed between the electrodes is indicative of sulfide concentration and hence of disease condition.
- the method of the '161 patent is very accurate; however, it has been found that, in some instances, the sulfide can poison the reference electrode surface and lead to inaccurate results.
- the problem of sulfide poisoning is particularly severe when high sulfide concentrations are present and/or when a repetitive series of measurements are made.
- the potential between the electrodes will depend on the ionic environment of each electrode.
- sulfide measuring systems such as those of the '161 patent, it has been found that the measured potential will depend upon the chloride environment of the reference electrode. This effect is particularly significant when the two electrodes are physically separated, since the chloride environment of the reference electrode may vary from that of the measuring electrode in an unpredictable manner. The problem is complicated even further when a series of measurements are made on a given patient; because, in such instances, the probe is typically rinsed between readings, and rinsing can change the ionic environment of the electrodes.
- a system for assessing the presence and extent of periodontal disease includes a probe which is insensitive to poisoning by sulfide compounds. Additionally, the system allows a practitioner to non- visually monitor sulfide level concentrations, in real time, while manipulating the probe within the periodontal sulcus.
- the probe for diagnosing the presence and extent of disease in a periodontal pocket containing sulcal fluid, by measuring the concentration of sulfides in said fluid.
- the probe comprises a housing having a first end which defines a tip configured to probe a periodontal pocket.
- a sulfide responsive measuring electrode is supported by the housing with a surface portion thereof disposed in the tip so as to establish fluid communication with the sulcal fluid when the tip is disposed in the pocket.
- the probe further includes a reference electrode supported by the housing at a location which will not directly contact the sulcal fluid when the tip is disposed in the pocket.
- the reference electrode has a surface portion thereof disposed in a body of a salt.
- the probe also includes a salt bridge material which is disposed so as to establish a conductive path between the body of salt and measuring electrode when the tip is disposed in the sulcal fluid.
- the probe further includes a first electrical lead in communication with the measuring electrode and a second electrical lead in electrical communication with the reference electrode. The probe is operative, when immersed in the sulcal fluid, to generate an electrical potential between the measuring electrode and the reference electrode which is proportioned to a concentration of sulfide in the sulcal fluid.
- the probe includes a hydration layer supported by the housing between the measuring electrode and reference electrode.
- the hydration layer may comprise a polymeric matrix having a salt residue disposed in the pores.
- the polymeric material comprises cellulose acetate, and the pores contain an aqueous phase comprising a salt solution.
- the reference electrode is disposed in a pellet of a salt such as potassium chloride, and a major portion of the pellet of salt is covered with a moisture impervious material so as to leave only a small opening for fluid access to the salt pellet.
- the salt bridge material may, in one instance, comprise an organic matrix having particles of a salt dispersed therein.
- the probe includes an auditory signal generator associated therewith for sensing the potential generated between the measuring electrode and reference electrode, and providing an auditory signal corresponding thereto.
- Figure 1 is a depiction of a probe structured in accord with the present invention
- Figure 2 is an enlarged, cross-sectional view of a portion of the probe of Figure 1;
- Figure 3 is a cross-sectional view of the probe of Figure 2 taken along line 3-3;
- Figure 4 is an end view of the probe of Figure 2;
- Figure 5 is an enlarged, cross-sectional view of a portion of the probe of Figure 2 better illustrating the reference electrode and salt block.
- the present invention is directed to a periodontal probe for measuring the sulfide concentration of sulcal fluid.
- the probe of the present invention is resistant to sulfide poisoning, and is stable in operation through repeated rinsings.
- Figure 1 depicts a typical probe 10 structured in accord with the principles of the present invention.
- the probe 10 includes a housing 12 having a length and a diameter configured to be easily handled by a practitioner and manipulated in the mouth of a patient.
- a portion of the housing 14 is configured to define a relatively small diameter tip configured to enter a patient's sulcal pockets.
- the probe 10 includes a sulfide responsive measuring electrode, and a reference electrode. These electrodes each connected to a respective, electrically conductive lead 16, 18 shown herein in phantom outline.
- the leads 16, 18 are in electrical communication with an electro ⁇ chemical analyzer 20 which may optionally include a sound generator 24 in communication therewith.
- the probe is disposed so that the tip portion thereof is immersed in the patient's sulcal fluid so that the measuring electrode contacts the fluid.
- the reference electrode is also in electrical communication with the sulcal fluid, via a salt bridge, as will be described in greater detail hereinbelow; although, the reference electrode may not be actually immersed in the sulcal fluid.
- An electrical potential is developed between the measuring electrode and the reference electrode, and this potential is proportional to the sulfide concentration in the sulcal fluid.
- the electro ⁇ chemical analyzer 20 is operative to sense the potential between the electrodes and to provide a display which is directly indicative of, or correlatable with, sulfide concentration.
- a sound generator 24 may be utilized in combination with the electro-chemical analyzer 20.
- the sound generator 24 produces an audible signal which is indicative of the potential generated between the electrodes.
- the sound generator may be operative to provide a signal having a pitch or volume which varies as a function of the measured potential; or, the sound generator 24 may be operative in a threshold manner to provide a signal only if a preselected potential is achieved.
- sulfide concentration in a sulcal pocket may have a spatial variation. Generally, it is most desirable to measure the highest sulfide concentration.
- the use of an audible signal generator simplifies probing of the pocket by providing a direct, non-visual signal indicative of the magnitude of the potential.
- the electro-chemical analyzer may be operative to store the highest potential measured so as to permit later reference thereto. Referring now to Figure 2, there is shown an enlarged, cross-sectional view of a portion 14 of the probe 10, including the tip portion at the first end 28 thereof which, in the operation of the probe, is placed in the periodontal pocket.
- the portion of the housing shown in Figure 2 is configured as a generally tapered member 42 fabricated from a body of an electrically insulating material, such as polymer.
- the housing may comprise a body of solid material onto which the various components of the tip are attached, or it may be made from a curable resin.
- a sulfide responsive measuring electrode 30 is disposed therein.
- This electrode 30 is most preferably fabricated from a material which undergoes an electro ⁇ chemical reaction with the sulfide ion.
- One particularly preferred material comprises silver, and accordingly, the electrode 30 may be simply comprised of a fine silver wire. In other instances, the electrode may comprise a wire, such as a stainless steel wire, coated with silver.
- the measuring electrode 30 is disposed so that a surface portion thereof, for example portion 30' as shown in Figure 4, is exposed at the tip 28 end of the probe for contact with sulcal fluid.
- a reference electrode disposed in an electro-chemical relationship with the measuring electrode 30 must be employed in order to provide a potential indicative of a sulfide ion concentration.
- a reference electrode 32 is disposed in the probe.
- One particularly preferred reference electrode comprises a silver/silver chloride electrode, typically provided by disposing a chloride coating on a silver wire.
- the chloride coating will be disposed to cover a substantial length of the wire, and in other instances, the wire will be insulated along substantially all of its length, and will have a body of silver chloride disposed so as to cover a free end of the wire. All such configurations may be employed in the practice of the present invention.
- the operating voltage of the reference electrode is dependent upon the logarithm of the chloride ion concentration to which it is exposed. And in the use of electrode systems of the prior art, it has been found that the chloride ion concentration in the vicinity of the reference electrode can vary over a wide range of values and such variation is further increased when the electrode is rinsed between uses. Variations of chloride concentration lead to fluctuations in the reference voltage, and hence a variation in the final reading of sulfide ion concentration. In accord with the present invention, it has been found that the output of the reference electrode can be stabilized, if the electrode is disposed in a saturated chloride solution. Toward that end, the reference electrode 32 is disposed within a pellet of a salt, such as potassium chloride 34.
- a salt such as potassium chloride 34.
- the pellet of potassium chloride 34 is partially covered by the material of the housing 42, and preferably has a major portion of its free surface covered by a moisture impervious material 36, such as a layer of epoxy resin.
- the moisture impervious layer 36 covers most, but not all, of the pellet 34.
- a salt bridge 38 extends from the salt pellet 34 to the tip 28 of the probe.
- a salt bridge material comprises a body having mobile ions contained therein for providing ionic conductivity therethrough.
- One particularly preferred salt bridge material for the practice of the present invention comprises an organic matrix defining an open lattice having a plurality of interconnected channels therethrough with an aqueous salt solution contained in the channels.
- One specific and preferred salt bridge material comprises an epoxy polymer matrix with potassium chloride contained therein. It has been found, in accord with the present invention, that a salt bridge may be readily provided within the probe by disposing a layer 38 of an epoxy polymer having a salt dispersed therein, between the salt pellet 34 surrounding the reference electrode 32, and the region of the tip proximate the measuring electrode 30.
- the salt bridge is prepared by coating a thin layer of curable epoxy resin and sprinkling potassium chloride salt onto the unhardened epoxy layer.
- the salt penetrates the layer, and the layer subsequently hardens.
- salt bridge layer is hydrated during the initial wash of the electrode, salt exposed on the surface of the bridge hydrates forming an electrically conductive surface layer.
- the salt embedded within the underlying matrix is leached from the matrix during successive washings so as to regenerate the conductive surface.
- potassium chloride is particularly preferred because the mobility of the potassium ions and the chloride ions in solution is comparable, thereby avoiding space charge effects and the like.
- the salt bridge may be fabricated from any matrix material, including organic as well as inorganic materials, which can contain salt crystals, which crystals are subsequently leached during hydration and operation of the bridge.
- a hydration layer 40 on the probe in the region of the reference electrode, measuring electrode and salt bridge.
- the hydration layer comprises a smooth, open structured, over coated layer which assures the maintenance of hydrated conditions between the electrodes and salt bridge and allows for wider tolerances in the fabrication of the salt bridge.
- the hydration layer 40 comprises a layer overcoating the tip portion of the probe, and as such covers the salt bridge layer 38.
- One particular hydration layer is comprised of a porous cellulose acetate layer containing a salt residue lining the pores.
- the layer may be prepared by coating an emulsion comprising an organic phase, which is an organic cellulose acetate solution, and an aqueous phase which comprises an aqueous salt solution. Upon evaporation of the organic solvent, the water based phase is trapped within the cellulose acetate matrix. Subsequent evaporation of the water droplets opens small pores in the coating matrix and leaves a salt residue that assists in hydration of the coating during the initial wash/hydration step. A number of different materials may be utilized for the hydration layer.
- a hydration layer may be prepared from a 30% solution of cellulose acetate in acetone formed into an emulsion with up to 1% of an aqueous solution of 4M potassium chloride.
- Other embodiments of hydration layer may similarly be prepared from a variety of polymers such as cellulose acetate-butyrate, vinyls, and the like.
- the polymer and solvent system should be chosen so as to allow for initial evaporation of the organic phase with the aqueous phase remaining, so as to provide the porous, salt containing matrix.
- the probe of the present invention is first rinsed with a wash/hydration solution so as to wet the hydration layer, salt bridge, and salt pellet.
- the wash/hydration solution may simply comprise water, or may comprise a dilute salt solution and may further include disinfectants, surfactants and the like.
- the probe is placed in electrical connection with a standard electrochemical analyzer such as a D.G. Electro-Chem analyzer (Model 1200) by means of a standard connector such as a mini coaxial connector cable, which is attached to the first and second leads of the probe.
- the mode switch of the analyzer is set down to a reference position and the selector control to the lower volt position (inactivating most other controls) .
- the power supply switch of the analyzer is turned on and the probe tip may be placed in a sterile 0.5 molar NaCl solution.
- a base line reading may be taken which will usually vary between 30-100 mV+, reflecting the potential difference between the first and second electrodes in the probe, that is, the silver versus silver/silver chloride potential in the saline solution.
- the probe may then be dipped into a calibration solution including a known concentration of sulfide ion to verify operation thereof.
- the probe is ready for insertion into a periodontal pocket of a patient.
- the probe is inserted so that it comes into contact with the periodontal sulcal fluid contained therein.
- the probe is configured so that the reference electrode does not directly contact the sulcal fluid in normal use.
- the electrolytes within the sulcal fluid will cause an electrical potential to develop between the electrodes, the magnitude of which corresponds to the concentration of sulfide in the fluid.
- a clearly, clinically-observable diseased or inflamed pocket should produce a readout on the analyzer in the 500-700 mV+ range.
- Responses in the range of 250-500 mV+ may indicate subclinical disease activity not readily diagnosable by conventional means. Readings below this level may be borderline. Readings below the borderline (i.e. 250 mV+) down to the base line (typically 30-100 mV+) generally indicate an absence of active disease.
- the probe tip After measurement of each pocket, the probe tip is immersed in a sterile rinse solution.
- the particular configuration of the reference electrode prevents disintegration and depletion of the salt during the rinse steps.
- the probe may be fabricated in an inverted embodiment wherein the housing may comprise a hollow, tapered cylindrical body which encloses the measuring electrode as well as the reference electrode, salt pellet, salt bridge and hydration layer.
- the measuring electrode will comprise a cylindrical body which forms the tip itself as well as the electrode.
- the reference electrode may be disposed upon an electrically insulating coating covering a portion of the body forming the reference electrode, and may be connected thereto by the salt bridge as previously noted.
- the reference electrode may be disposed in yet other configurations, provided that it is separated from the sulcal " fluid by salt bridge material and provided that ionic conductivity between the reference electrode and measuring electrode is established.
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Biophysics (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Dentistry (AREA)
- Epidemiology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96916691A EP0957816A1 (en) | 1995-06-12 | 1996-05-29 | Improved apparatus for measuring sulfides within a periodontal pocket |
JP9503083A JPH11508157A (en) | 1995-06-12 | 1996-05-29 | An improved instrument for measuring sulfides in periodontal ligament pockets |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/489,657 US5628312A (en) | 1995-06-12 | 1995-06-12 | Apparatus for measuring sulfides within a periodontal pocket |
US08/489,657 | 1995-06-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996041587A1 true WO1996041587A1 (en) | 1996-12-27 |
Family
ID=23944741
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1996/007834 WO1996041587A1 (en) | 1995-06-12 | 1996-05-29 | Improved apparatus for measuring sulfides within a periodontal pocket |
Country Status (5)
Country | Link |
---|---|
US (1) | US5628312A (en) |
EP (1) | EP0957816A1 (en) |
JP (1) | JPH11508157A (en) |
CA (1) | CA2224078A1 (en) |
WO (1) | WO1996041587A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6264615B1 (en) * | 1999-01-21 | 2001-07-24 | Diamond General Development Corporation | Method for diagnosing the presence and extent of halitosis activity |
JP5812681B2 (en) * | 2010-05-19 | 2015-11-17 | アークレイ株式会社 | Electrochemical sensor |
CN111693264B (en) * | 2020-06-16 | 2021-03-16 | 清华大学 | Fluid machinery diagnosis system and method based on artificial intelligence and big data |
US12082788B1 (en) * | 2023-08-03 | 2024-09-10 | King Faisal University | Gingival crevicular fluid absorbing brush |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4334540A (en) | 1979-05-01 | 1982-06-15 | Monell Chemical Senses Center | Method of diagnosing periodontal disease through the detection of pyridine compounds |
US4713164A (en) | 1985-07-25 | 1987-12-15 | Confidence Corporation | Apparatus for analyzing malodors in the breath |
US5144753A (en) * | 1991-03-25 | 1992-09-08 | Murphy Gordon J | Probe instrument |
US5275161A (en) | 1992-03-09 | 1994-01-04 | Diamond General Development Corporation | Method of and apparatus for measuring sulfides within a periodontal pocket |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8507319D0 (en) * | 1985-03-21 | 1985-05-01 | Vs Remek Ltd | Measuring instruments |
EP0384548A3 (en) * | 1986-03-31 | 1990-11-28 | Jerome B. Ackerman | Measuring probe |
DD274169A1 (en) * | 1988-07-19 | 1989-12-13 | Univ Rostock | DEVICE FOR CONTROLLING INTRUSION DEVICE OF MACHINE-DRIVEN STOMATOLOGICAL TREATMENT INSTRUMENTS |
US5131844A (en) * | 1991-04-08 | 1992-07-21 | Foster-Miller, Inc. | Contact digitizer, particularly for dental applications |
US5211556A (en) * | 1991-11-27 | 1993-05-18 | Kabushiki Kaisha Morita Seisakusho | Root canal meter |
US5318442A (en) * | 1992-05-18 | 1994-06-07 | Marjorie K. Jeffcoat | Periodontal probe |
-
1995
- 1995-06-12 US US08/489,657 patent/US5628312A/en not_active Expired - Fee Related
-
1996
- 1996-05-29 EP EP96916691A patent/EP0957816A1/en not_active Withdrawn
- 1996-05-29 WO PCT/US1996/007834 patent/WO1996041587A1/en not_active Application Discontinuation
- 1996-05-29 CA CA002224078A patent/CA2224078A1/en not_active Abandoned
- 1996-05-29 JP JP9503083A patent/JPH11508157A/en not_active Ceased
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4334540A (en) | 1979-05-01 | 1982-06-15 | Monell Chemical Senses Center | Method of diagnosing periodontal disease through the detection of pyridine compounds |
US4713164A (en) | 1985-07-25 | 1987-12-15 | Confidence Corporation | Apparatus for analyzing malodors in the breath |
US5144753A (en) * | 1991-03-25 | 1992-09-08 | Murphy Gordon J | Probe instrument |
US5275161A (en) | 1992-03-09 | 1994-01-04 | Diamond General Development Corporation | Method of and apparatus for measuring sulfides within a periodontal pocket |
Non-Patent Citations (4)
Title |
---|
A. HOROWITZ AND L.E. FOLE, PERIDONTAL ABSTRACTS, vol. 20, no. 59, 1972 |
A.A. RIZZO (1967), PERIODONTICS, vol. 5, no. 233, 1967 |
G.R. METTRAUX ET AL. (1983), JOURNAL OF PERIDONTOLOGY, vol. 55, 1983, pages 516-521 |
M.C. SOLIS- GAFFAR, K.N. RUSTOGI AND A. GAFFAR(OCT.1980), JOURNAL OF PERIDONTOLOGY, October 1980 (1980-10-01), pages 603-606 |
Also Published As
Publication number | Publication date |
---|---|
JPH11508157A (en) | 1999-07-21 |
US5628312A (en) | 1997-05-13 |
EP0957816A1 (en) | 1999-11-24 |
CA2224078A1 (en) | 1996-12-27 |
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