A carrier for dental uses

Abstract

The disclosure is directed to a dental carrier for colorimetric dental heath detection (e.g., detecting the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, or precursor thereof).

Description

[0001] A CARRIER FOR DENTAL USES

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Provisional Application No. 63 / 543,753, filed on October 12, 2023, the entire contents of which are incorporated herein.

[0004] FIELD

[0005] The present disclosure relates to a dental carrier for detecting the presence or absence of dental caries, higher caries risk, and / or cavity or cavities.

[0006] BACKGROUND

[0007] Dental caries, and / or cavity or cavities, is the most prevalent oral disease caused by acid secreting bacteria. Salivary pH below 5.5 is indicative of the presence of active demineralization of the teeth without wishing to be bound by theory. Dental caries, and / or cavity or cavities, are caused by acidic salivary pH which results in an imbalance between the demineralization and remineralization processes of the enamel, as protons causes the decomposition of the hydroxyapatite crystals. Local detection of pH imbalance thus provides an early indication of tooth demineralization before it matures into full decay.

[0008] Current detection methods are limited to dental practices and therefore are expensive and impractical for regular monitoring in and outside of the dental office. Thus, there remains a significant need for compositions and methods that improve the detection and monitoring of dental caries, and / or cavity or cavities.

[0009] SUMMARY

[0010] Accordingly, in various aspects, the present disclosure relates to a dental carrier and methods that detect the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, as well as information on cavity activity using a rapid unambiguous color indicator that allows for visualization, e.g. by an unassisted eye.

[0011] In aspects, there is provided a device for detection of a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, and / or cavity activity risk, and / or caries risk and / or demineralization and / or cavity demineralization risk, or precursor thereof, comprising (a) a carrier, selected from a tray, a sticker, or a paper made holder, comprising a substrate attached to or layered thereto and being suitable for comprising a sensing agent, where the carrier or the sensing agent contacts or is suitable for contacting a plurality of surfaces of one or more teeth and the substrate is or comprises a biologically compatible polymer matrix or biopolymer matrix material; and (b) a sensing agent, the sensing agent being suitable for providing a color change which is indicative of a pH value associated with the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, caries activity, or precursor thereof, where the sensing agent is a synthetic compound, optionally where the synthetic compound is not derived from food.

[0012] In embodiments, the substrate is or comprises one or more of a hydrogel, cellulosic, elastomer, hydrocolloid, and / or a malleable organic, non-organic, or a partially organic solid material. In embodiments, the substrate is or comprises one or more of an alginate-based material, gum base, wax, and / or a siloxane-based material. In embodiments, the substrate is or comprises alginate.

[0013] In embodiments, the sensing agent is a synthetic dye. In embodiments, the synthetic dye is a dye of the triphenylmethane family. In embodiments, sensing agent is bromocresol purple (BCP).

[0014] In aspects, there is provided a method of detecting a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, or caries associated with bacterial acid production, or precursor thereof in a subject, comprising (a) contacting a surface of one or more teeth with the device of the present disclosure and (b) determining a color change in the sensing agent, the color change being indicative of a pH value, and / or other ions or compounds having a concentration adjacent to a specific tooth surface that is associated with the presence or absence of tooth demineralization, dental caries, risk for caries, caries associated bacterial acid production, and / or cavity or cavities, or precursor thereof, and / or risk of developing dental caries, and / or cavity or cavities presence or activity.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIGURE 1 shows high water content alginate hydrogels containing anthocyanins as pH indicators at different pHs.

[0017] FIGURE 2 shows high water content alginate hydrogel containing anthocyanins as pH indicators before and 1 min after exposure to HC1 solution pH of 2. FIGURE 3 shows high water content PEO hydrogel containing anthocyanins as pH indicators before and 1 min after exposure to HC1 solution pH of 2.

[0018] FIGURE 4 shows high water content alginate hydrogel containing Methyl Red (MR) as pH indicator before and 1 min after exposure to HC1 solution pH of 3 and 4.

[0019] FIGURE 5 shows alginate hydrogel containing MR as pH indicator 1 min after exposure to different volumetric amounts of artificial saliva (AS) at different pHs, 7.0 and 5.5.

[0020] FIGURE 6A shows alginate hydrogels with Bromocresol Purple (BCP) (0.3 mM) as pH indicator 1 min after exposure to different AS (2 pL) droplets with 4 different pHs organized in a rhombus shape: 6.8 (top), 6.1 (right), 5.2 (bottom), and 4.5 (left). The approximate color transition pH was estimated by observing how the different AS pHs changed the color of the hydrogel.

[0021] FIGURE 6B shows alginate hydrogels containing MR, Phenol red (PR) and Bromothymol Blue (BTB) (0.1 mM), respectively, as pH indicators 1 min after exposure to different AS (2 pL) with pHs, 6.8 (top), 6.1 (right), 5.2 (bottom), and 4.5 (left).

[0022] FIGURE 7 shows alginate hydrogels with BCP (0.3 mM) as pH indicator 1 min after exposure to different AS (2 pL) with pHs, 6.8 (top), 6.1 (right), 5.2 (bottom), and 4.5 (left). The relative pH of the gel is the estimated pH value that the color of the gel represents.

[0023] FIGURE 8A shows alginate hydrogel containing BCP at different times after dental imprint and exposure to AS at different pHs: (a) 1 min, (b) 5 min, (c) 15 min, and (d) 45 min. (a) shows the specific AS pHs that each tooth imprint contacted.

[0024] FIGURE 8B shows alginate hydrogel containing MR 5 min after dental imprint and exposure to AS at different pHs. The numbers in the figure represent the specific AS pHs that each tooth imprint contacted.

[0025] FIGURE 9 shows wax-based and siloxane-based materials containing BCP 1 min after being exposed to AS at different pHs (6.8 and 4.5).

[0026] FIGURE 10 is an image showing a two-component material after being mixed and loaded in a tray, and then having an impression taken with a dental set.

[0027] FIGURE 11 is an image showing how the material demonstrates a color change with saliva at pH 5.1, but not with saliva at pH 6.6. FIGURE 12 is an image showing how gum based materials demonstrate a color change with a dental set pre-wetted with saliva at pH 5.1, but not with a dental set pre-wetted with saliva at pH 6.6.

[0028] DETAILED DESCRIPTION

[0029] The present invention is based, in part, on the discovery of a dental carrier device (e.g., a gel, tray, sticker, or paper made holder), and methods of use, for detection of a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, and / or cavity activity risk, and / or caries risk, and / or demineralization and / or cavity demineralization risk, or precursor thereof, using a rapid unambiguous color indicator.

[0030] In aspects, there is provided a device for detection of a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, and / or cavity activity risk, and / or caries risk, and / or demineralization and / or cavity demineralization risk, or precursor thereof, comprising (a) a carrier, selected from a tray, a sticker, or a paper made holder, comprising a substrate attached to or layered thereto and being suitable for comprising a sensing agent, where the carrier contacts or is suitable for contacting a plurality of surfaces of one or more teeth and the substrate is or comprises a biologically compatible polymer matrix or biopolymer matrix material; and (b) a sensing agent, the sensing agent being suitable for providing a color change which is indicative of a pH value associated with the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, caries activity, or precursor thereof, where the sensing agent is a synthetic compound, optionally where the synthetic compound is not derived from food.

[0031] In aspects, there is provided a method of detecting a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, or caries associated with bacterial acid production, or precursor thereof in a subject, comprising (a) contacting a surface of one or more teeth with the device of the present disclosure and (b) determining a color change in the sensing agent, the color change being indicative of a pH value, and / or other ions or compounds having a concentration adjacent to a specific tooth surface that is associated with the presence or absence of tooth demineralization, dental caries, risk for caries, caries associated bacterial acid production, and / or cavity or cavities, or precursor thereof, and / or risk of developing dental caries, and / or cavity or cavities presence or activity. In embodiments, the carrier contacts or is suitable for contacting one or more of distal, facial, incisal, lingual, mesial, occlusal, and proximal surfaces.

[0032] In embodiments, the carrier is 3D printed or 3D printable, or other polymer based carrier, or a sticker or any other type of carrier for a gel or a viscous material that is malleable.

[0033] In embodiments, the carrier is a two-component material comprising 1) a mixture containing at least a polysaccharide, a divalent salt, and a filler, and 2) an aqueous solution. In embodiments, the material comprises at least a sensing agent and other ingredients in either of the two components. In embodiments, the two components are mixed to prepare a paste. In embodiments, the paste is suitable to be loaded on a carrier to contact teeth in multiple areas. In embodiments, the paste can change to stiffer consistency or not. In embodiments, the paste does not change consistency.

[0034] In embodiments, polysaccharides of the two-component material are selected from materials that include, but are not limited to, alginate, alginic acid, alginic salts, agar, carrageenan, pullulan, curdlan, Xanthan gum, gellan gum, pectin, konjac glucomannan, Xyloglucan, guar gum, gum arabic, and locust bean gum.

[0035] In embodiments, the divalent salt is selected from materials that include, but are not limited to, calcium sulfate, dihydrate calcium sulfate, hemihydrate of calcium sulfate, calcium chloride, calcium gluconate, magnesium sulfate, magnesium chloride, iron chloride, and zinc chloride.

[0036] In embodiments, the filler is selected from materials that include, but are not limited to, diatomaceous earth or Celite, cellulose, modified cellulose, zinc oxide, silicate, calcium carbonate, and silicon oxide.

[0037] In embodiments, the other components of the two-component material are selected from materials that include, but are not limited to, sodium pyrophosphate, sodium phosphate, sodium biphosphate, sodium triphosphate, sodium bicarbonate, calcium fluoride, sodium fluoride, and sodium fluorosilicate.

[0038] In embodiments, the sensing agent is substantially absorbed into the substrate. In embodiments, the sensing agent covers substantially the entire external surface of the substrate. In embodiments, the sensing agent is contained within the substrate. In embodiments, the sensing agent is applied to the substrate in a monolayer, a bilayer, a solution, or on a surface. In embodiments, the substrate is or comprises one or more of a hydrogel, cellulosic, elastomer, hydrocolloid, and / or a malleable, organic, non-organic, or a partially organic solid material. In embodiments, the substrate is or comprises one or more of an alginate-based material, gum base, wax, and / or a siloxane-based material. In embodiments, the substrate is or comprises alginate.

[0039] In embodiments, the gum-based material comprises as least a thermoplastic polymer, a sensing agent, a fdler and other components. In embodiments, the gum-based material is able to deform and contact multiple teeth and tooth surfaces with or without a carrier.

[0040] In embodiments, the thermoplastic polymer is selected from materials that include, but are not limited to, polyvinyl acetate, butyl rubber, polybutadiene, butadiene styrene rubber, isobutyleneisoprene copolymer, and polyisobutylene.

[0041] In embodiments, the fdler is selected from materials that include, but are not limited to, diatomaceous earth or Celite, cellulose, modified cellulose, zinc oxide, silicate, calcium carbonate, and silicon oxide. Other components are selected from materials that include, but are not limited to, water, glycerol, polyols, sugars, sugar alcohols, NaOH, plasticizers, and flavoring agents.

[0042] In embodiments, the substrate further comprises a surfactant. In embodiments, the surfactant is a negative surfactant, e.g., sodium lauryl sulfate (SLS). In embodiments, the surfactant is a neutral surfactant e.g., selected from TWEEN20 (polysorbate 20), TWEEN80 (polysorbate 80), and SPAN80 (sorbitane monooleate, sorbitan oleate). In embodiments, the surfactant is a positive surfactant e.g., ADOGEN464 (methyltrialkyl(C8-C10)ammonium chloride).

[0043] In embodiments, the sensing agent has a high light absorbance. In embodiments, the sensing agent has a high light absorbance and is applied to the substrate in a monolayer, a bilayer, a solution, or on a surface. In embodiments, the sensing agent has a low light absorbance, optionally wherein the sensing agent is applied to the substrate in solution, or on a surface. In embodiments, the sensing agent has a low light absorbance and is applied to the substrate in a multilayer, optionally about 3, or about 4, or about 5, or about 6, or about 7, or about 8, or about 9, or about 10 layers. In embodiments, the sensing agent is a synthetic dye. In embodiments, the synthetic dye is a member of the triphenylmethane family. In embodiments, the sensing agent is selected from bromocresol purple (BCP), phenol red (PR), bromothymol blue (BTB), methyl red (MR), and bromothymol blue (BTB). In embodiments, the sensing agent is bromocresol purple (BCP). In embodiments, the device or method is suitable for displaying a color change of a first color to a second color that indicates a specific pH value. In embodiments, the device or method is suitable for displaying a color change of a first color to a second color that does not indicate a specific pH value. In embodiments, the first color is a primary color, e.g., one of red, yellow, or blue. In embodiments, the first color is a secondary color, e.g., one of orange, green, or violet. In embodiments, the first color is a tertiary color, e.g., one of red-orange, yellow-orange, yellowgreen, blue-green, blue-violet, or red-violet. In embodiments, the second color is a primary color, e.g., one of red, yellow, or blue. In embodiments, the second color is a secondary color, e.g., one of orange, green, or violet. In embodiments, the second color is a tertiary color, e.g., one of red- orange, yellow-orange, yellow-green, blue-green, blue-violet, or red-violet. In embodiments, the device or method is suitable for displaying a color change of colored to colorless, or substantially colorless, that indicates a specific pH value. In embodiments, the device or method is suitable for displaying a color change of colorless, or substantially colorless, to colored that indicates a specific pH value. In embodiments, the device or method is suitable for displaying a color change of colored to colorless, or substantially colorless, that does not indicate a specific pH value. In embodiments, the device or method is suitable for displaying a color change of colorless, or substantially colorless, to colored that does not indicate a specific pH value, or optionally wherein the device or method is suitable for displaying a color change of colorless that is revealing or disappearing of a pattern that is embedded on the substrate, wherein stripes disappear and / or appear when the test is positive or negative.

[0044] In embodiments, the device or method is suitable for identifying an active caries and / or cavity, or a lack of an active caries and / or cavity. In embodiments, the pH value is about 5.5. In embodiments, the pH value is about 5.5 and indicative of the presence of dental caries, and / or cavity or cavities, or precursor thereof, and / or a risk of developing dental caries.

[0045] In embodiments, the pH value is not about 5.5. In embodiments, the pH value is not about 5.5 and indicative of the absence of dental caries, and / or cavity or cavities, or precursor thereof.

[0046] In embodiments, the device or method is suitable for detecting demineralization, optionally of calcium, fluoride, and / or phosphate ions, optionally from enamel and / or dentin, optionally of enamel producing proteins and / or periodontal ligament degrading enzymes, optionally wherein the dentin and enamel producing proteins are selected from collagen and amelogenin, optionally wherein the dentin or periodontal ligament degrading enzyme is collagenase, optionally wherein the periodontal ligament degrading enzyme differentiates between deep and early stage cavities, optionally wherein the device or method detects demineralization of a catabolic enzyme, and optionally wherein the catabolic enzyme is a protease, sucrase, or sucrose synthase.

[0047] In embodiments, the device or method is suitable for detecting a lack or an absence of demineralization, optionally of calcium, fluoride, and / or phosphate ions, optionally from enamel and / or dentin.

[0048] In embodiments, the device or method is suitable for detecting activity of acid-secreting bacteria, optionally wherein the device or method detects increases in the activity of acid-secreting bacteria. In embodiments, the device or method is suitable for detecting activity of Streptococci mutans, Streptococcus sobrinus, and / or Lactobacilli spp. In embodiments, the device or method is suitable for detecting lack of activity of acid-secreting bacteria. In embodiments, the device or method is suitable for detecting lack of activity of Streptococci mutans, Streptococcus sobrinus, and / or Lactobacilli spp., optionally wherein the device or method detects bacterial acid secretion after intentional activation of bacterial acid secretion, optionally wherein the device or method detects increases in bacterial acid secretion and / or bacterial activity.

[0049] In embodiments, the device or method is suitable for detecting a dental lesion.

[0050] In embodiments, the device or method is suitable for distinguishing between active and arrested lesions. In embodiments, the device or method is suitable for detecting an incipient dental lesion. In embodiments, the device or method is suitable for detecting a reversible dental lesion, optionally wherein the device or method detects the depth of the dental lesion. In embodiments, the device or method is suitable for detecting a remineralizable dental lesion.

[0051] In embodiments, the device or method is suitable for at-home detection. In embodiments, the device is suitable for detection by an end user. In embodiments, the device or method is suitable for minimally invasive detection. In embodiments, the device or method provides a signal that is visualizable by an unassisted eye.

[0052] In embodiments, the device contacts a plurality of tooth surfaces using soft polymeric materials and relying on elastic, and / or plastic deformations of the substrate material. In embodiments, the substrate material become stiffer (e.g., setting) when in the mouth and in contact with the teeth. In embodiments, the substrate material to becomes stiffer (setting) via one or more of electrostatic interactions, covalent bonds, temperature, phase separation, and / or other mechanisms. In embodiments, the device is soft when placed in the mouth and rigid when removed. In embodiments, the device is an elastic material with no setting mechanism required. In embodiments, the device is a viscoelastic material with no setting mechanism required.

[0053] In embodiments, the present subject is at risk of developing dental caries. In embodiments, the present subject is predisposed to the dental caries. In embodiments, the present subject has a personal or family history, or has a mutation in a gene that reduces enamel or otherwise causes dental caries) or shows early signs or symptoms of dental caries and / or cavity or cavities. In embodiments, the subject presents with poor oral hygiene, a diet high in sugar, other factors that reduce enamel, limited access to dental care, and / or absence of fluoridated water. In embodiments, visual inspection, fluorescence imaging, X-rays, and / or medical / dental history reveals a subject with or at risk of dental caries and / or cavity or cavities. In embodiments, the surface of the tooth of the subject is soft when probed with a sharp instrument. In embodiments, saliva or a dental plaque sample from the subject is obtained to determine the presence or absence of a particular bacteria, in order to determine the risk of developing dental caries and / or cavity or cavities. Also, without wishing to be bound by theory, a subject currently with dental caries and / or cavity or cavities, in embodiments, has one or more than one symptom and may have been previously diagnosed with the dental caries and / or cavity or cavities.

[0054] In embodiments, characteristics that place the subject at high risk of developing dental caries, and / or cavity or cavities include sugary foods or drinks, dry mouth (Xerostomia; ages >6 years) or visually inadequate salivary flow either physiological, medicine related or due to radiation or disease, clinically detectable early, shallow, or microcavitations (moderate decay), and clinically detectable late or deep cavitations (extensive decay).

[0055] In embodiments, the dental caries, and / or cavity or cavities, or precursor thereof, is not readily detectable with visual -tactile examination.

[0056] In embodiments, the method provides at-home detection. In embodiments, the method provides for minimally invasive detection. In embodiments, the method provides a signal that is visualizable by an unassisted eye. In embodiments, the method provides a signal through a device (e.g., a phone application), and / or is based on an image analysis algorithm. In embodiments, the method provides a signal that is visualizable by a software through taking an image of the device.

[0057] In embodiments, the device or method augments or supplants a cavity detection method, optionally wherein the device or method augments or supplants radiographic detection, optionally bitewing radiography or other methods such as periapical radiography, panoramic radiography, or CBCT, Quantitative Light-induced Fluorescence (QLF), Fibre-optic Transillumination (FOTI), Electrical Conductance (EC), and fluorescence or dyed particles / nanoparticles.

[0058] In embodiments, the method is suitable for detecting pH in saliva. In embodiments, the method is suitable for detecting pH in gingival crevicular fluid.

[0059] In various aspects, disclosed herein is a method of detecting a response to a remineralization treatment of dental caries, and / or cavity or cavities, in a subject, comprising: (a) contacting a surface of one or more teeth with the device disclosed herein, and (b) determining a color change in the sensing agent, the color change being indicative of a pH value, and / or other ions or compounds having a concentration adjacent to a specific tooth surface that is associated with the presence or absence of tooth demineralization, dental caries, and / or cavity or cavities, and / or risk of developing dental caries, and / or cavity or cavities, wherein the lack of a pH value associated with the presence of dental caries, and / or cavity or cavities, is indicative of a therapeutic response to a remineralization treatment, or to an improved oral hygiene.

[0060] In various aspects, disclosed herein is a method of detecting a response to a remineralization treatment of dental caries, and / or cavity or cavities, in a subject, comprising: (a) contacting a surface of one or more teeth of the subject with a sensing agent, or a support and / or substrate comprising the sensing agent, the sensing agent being configured to colorimetrically detect pH of saliva, plaque, or gingival crevicular fluid; and (b) determining a color change in the sensing agent, the color change being indicative of a pH value, and / or other ions or compounds having a concentration adjacent to a specific tooth surface that is associated with the presence or absence of tooth demineralization, dental caries, and / or cavity or cavities, and / or risk of developing dental caries, and / or cavity or cavities, wherein the lack of a pH value associated with the presence of dental caries, and / or cavity or cavities, is indicative of a therapeutic response to a remineralization treatment, or to an improved oral hygiene. In embodiments, the remineralization treatment is selected from a fluoride agent, a calcium agent, and / or a phosphate agent. In embodiments, the fluoride agent is one or more of sodium fluoride, stannous fluoride, and acidulated phosphate fluoride. In embodiments, the method prevents the need for a filling, crown, root canal, or extraction.

[0061] Dental caries, and / or cavity or cavities, at early stages are typically incipient lesions, can be remineralized and thus are fully reversible. As used herein, in embodiments, “dental caries” is interchangeable with “cavity” and / or “cavities.” Interventions such as high fluoride, calcium and phosphor-based pastes already exist in the market. These treatments can be used in the dental chair or at home. However, to date, there is a limited capability for measuring localized salivary pH to assess and monitor the efficiency of these aforementioned treatment modalities, specifically from the home setting. As disclosed herein, localized salivary pH diagnostics that can be used both in the dentist chair and at home provide better diagnostics and treatment monitoring for both the patient and dentist. For illustrative utility as a diagnostic tool, a device for such purposes should allow for localized, personalized, and continuous (daily or weekly) sampling of saliva with a low volume of saliva (in pL range). The result would be rapidly visible to the user (e.g., within seconds), and conclusively with high precision and accuracy. Regular and repeated use of the device would allow for tracking and monitoring over time.

[0062] In embodiments, the present disclosure also provides kits that can detect the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, or precursor thereof, as described in the embodiments herein. A typical kit of the disclosure comprises various reagents including, for example, one or more devices as disclosed herein useful to detect the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, or precursor thereof. The kit can include a visualization surface to detect a color change by an unassisted eye. The kit can further comprise materials necessary for the evaluation, including a dental pick, toothpick, paper point, rubber tip stimulator, a gum stimulator, dental floss, gel form, tray, or test strip, and the like. The kit can further comprise a label or printed instructions instructing the use of described reagents, including a reference color card. The kit can further comprise a treatment to be tested.

[0063] As used herein, the word “include,” and its variants, is intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may also be useful in the materials, compositions, devices, and methods of this technology. Similarly, the terms “can” and “may” and their variants are intended to be non-limiting, such that recitation that an embodiment can or may comprise certain elements or features does not exclude other embodiments of the present technology that do not contain those elements or features. Although the open-ended term “comprising,” as a synonym of terms such as including, containing, or having, is used herein to describe and claim the disclosure, the present technology, or embodiments thereof, may alternatively be described using more limiting terms such as “consisting of’ or “consisting essentially of’ the recited ingredients.

[0064] Unless defined otherwise, all technical and scientific terms herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials, similar or equivalent to those described herein, can be used in the practice or testing of the present disclosure, the preferred methods and materials are described herein. All publications, patents, and patent publications cited are incorporated by reference herein in their entirety for all purposes.

[0065] This disclosure is further illustrated by the following non-limiting examples.

[0066] EXAMPLES

[0067] Example 1. High Water Content Hydrogels with Anthocyanin pH Indicator Using Citrate Buffers to Induce Color Change

[0068] This Example evaluated, inter alia, black currant extract (containing anthocyanin) color change in a hydrogel format using citrate buffers.

[0069] 19.6 g of black currant (BC) extract was mixed with 126 g of ultrapure water type I (UPW), for a BC extract concentration of 15.6 w / v%. This solution was filtered using filter paper no. 1 (expected retention of particle sizes above 11 pm). 3.75 g of UPW and 3.75 g of purified BC were mixed, then 0.5 g of sodium alginate and 2 g of filler (silica) were added. After mixing the components for 5 min the pH was measured to be 4.5 (red color). The pH was adjusted to 7.0 using NaOH solution of pH 13 (4 mL added), at this point a dark purple color was achieved.

[0070] Seven separate containers with 400 mg of the alginate mixture each were prepared. For each container 50 pL of the respective citrate buffer was added: 2M citrate buffer (final pH 4.0, color red), 0.5M citrate buffer (final pH 4.7, color dull magenta), 0.2M citrate buffer (final pH 5.5, color light purple), 0. IM citrate buffer (final pH 6.1, color dark purple), 0.067M citrate buffer (final pH 6.5, color dark purple), and UPW (final pH 7.0, color dark purple as a control). The pH change after the addition of the citrate buffer was monitored using a Mettler Toledo Micro pH Meter.

[0071] As shown in FIGURE 1, when changing the pH of the hydrogel from 7 to 4 a color change was readily detected. The most dramatic color change occurs between the pHs of 6 and 4, where the color transitioned from dark purple at pH 6.1, to a red color at pH of 4.

[0072] Example 2. High Water Content Alginate Hydrogels with Anthocyanin pH Indicators Using Hydrochloric Acid to Induce Color Change

[0073] This Example evaluated, inter alia, the black currant extract (containing anthocyanin) color change in an alginate hydrogel format using a strong acid solution with no buffering capacity.

[0074] Briefly, black currant extract was purified via dissolution in water and filtration to remove fibers and freeze dried to a fine powder. A 1 wt% solution using the fiberless powder was prepared and the pH was adjusted for a targeted pH level of 4 using NaOH solution of pH 13.

[0075] A hydrogel composed of 73 wt% BC extract solution (1 wt% BC extract), 20 wt% filler (silica), 7 wt% sodium alginate was well mixed to form a homogeneous hydrogel (white color) and the hydrogel (0.5 g) was exposed to 50 pL HC1 solution of pH of 2.

[0076] As shown in FIGURE 2, a color change from white to red was readily detected when the pH 2 HC1 solution contacts the hydrogel.

[0077] Example 3. High Water Content Polyethylene Oxide (PEO) Hydrogels with Anthocyanin, and Methyl Red pH Indicators Using Hydrochloric Acid to Induce Color Change

[0078] This Example evaluated, inter alia, the black currant extract (containing anthocyanin) color change in a PEO hydrogel format using a strong acid solution with no buffering capacity.

[0079] Black currant extract was purified via dissolution in water and filtration to remove fibers and freeze dried to a fine powder. A 1 wt% solution using the fiberless powder was prepared and the pH was adjusted for a targeted pH level of 4 using NaOH solution of pH 13.

[0080] A hydrogel composed of 73 wt% black currant extract solution (1 wt% black currant extract), 20 wt% filler (silica), 7 wt% sodium alginate was well mixed to form a homogeneous hydrogel (gray color).

[0081] The hydrogel (0.5 g) was exposed to 50 pL HC1 solution of pH of 2. As shown in FIGURE 3, a color change from white to red was detected when the pH 2 HC1 solution contacts the hydrogel.

[0082] Example 4. High Water Content Alginate Hydrogels with Methyl Red pH Indicator Using Hydrochloric Acid to Induce Color Change.

[0083] This Example evaluated, inter alia, the methyl red color change in an alginate hydrogel format using a strong acid solution with no buffering capacity.

[0084] 0.1 mM solution of methyl red (MR) in UPW was prepared with a final pH of 7.0. A hydrogel composed of 90 wt% MR solution (0.1 mM); 10 wt% sodium alginate was well mixed to form a homogeneous hydrogel (yellow color). The hydrogel (0.5 g) was exposed to 50 pL HC1 solution of pH of 2.

[0085] As shown in FIGURE 4, a color change from yellow to red was readily detected when the pH 3 HC1 solution contacts the hydrogel. When pH of 4 contacts the hydrogel the change was less visible.

[0086] Example 5. Testing the Volumetric Limit of Detection for Alginate Hydrogels with Methyl Red (MR) pH Indicator Using Artificial Saliva (AS) to Induce Color Change

[0087] This Example evaluated, inter alia, the volumetric detection limit of alginate hydrogels containing MR using artificial saliva as the color change inducing medium.

[0088] 0.1 mM solution of methyl red (MR) in UPW was prepared with a final pH of 7.0 A hydrogel composed of 61 wt% MR solution (0.1 mM); 13 wt% sodium alginate; 20 wt% cellulose microcrystalline (CMC), 1 wt% sodium lauryl sulfate (SLS), 5 wt% CaSCU was well mixed to form a homogeneous hydrogel (yellow color).

[0089] The hydrogel (0.3 g) was exposed to 2, 1, and 0.5 pL artificial saliva (Pickering Laboratories Inc.) at two different pHs (7.0 and 5.5)

[0090] As shown in FIGURE 5, a color change from yellow to red was readily detected when the hydrogel was exposed to pH of 5.5. Additionally, a small color change was observed when using pH of 7 for this specific composition. When removing SLS from the hydrogel the color change at a pH above 6 was not observed.

[0091] Example 6. Influence of Surfactants in The Color Change Transition of pH Indicators This Example evaluated, inter alia, the influence of surfactants in the color change transition of pH indicators.

[0092] Six 0.5 g hydrogels with 20 wt% CMC, 13 wt% sodium alginate, and 67 wt% UPW with Bromocresol Purple 0.3 mM (no pH adjustment needed, pH of 3.6) were mixed well to form a uniform hydrogel. 4 wt% of each surfactant was added into one of the hydrogel, SLS (anionic), TWEEN20 (polysorbate 20, neutral), TWEEN80 (polysorbate 80, neutral), SPAN80 (sorbitane monooleate, sorbitan oleate, neutral), and ADOGEN464 (methyltrialkyl(C8-C10)ammonium chloride, cationic).

[0093] Hydrogels were formed with 20 wt% CMC, 13 wt% sodium alginate, and 67 wt% UPW with Methyl red 0.1 mM (no pH adjustment needed, pH of 7), mix well to form a uniform hydrogel. Add 4 wt% SLS to the hydrogel.

[0094] The previous steps were repeated for Phenol red (PR) and Bromothymol Blue (BTB) 0.1 mM dyes.

[0095] The color change with artificial saliva (2 pL) at different pHs for all hydrogels (6.8, 6.1, 5.2, 4.5, not all pHs were tested for all hydrogels) was tested.

[0096] As shown in FIGURE 6A, shifts in the pH where the color change occurs are observed (from purple to yellow for BCP). Negative surfactant (SLS) significantly increased the pH where the color change transition occurs. Neutral surfactants (TWEEN20 (polysorbate 20), TWEEN80 (polysorbate 80), SPAN80 (sorbitane monooleate, sorbitan oleate)) increased (for TWEEN20 (polysorbate 20) and TWEEN80 (polysorbate 80)) or did not change the pH (for SPAN80 (sorbitane monooleate, sorbitan oleate)) where the color change transition occurs. Positive surfactant (ADOGEN464 (methyltrialkyl(C8-C10)ammonium chloride) significantly decreased the pH where the color change transition occurs. It was also observed that the hydrophilicity, saliva transport, and intensity of color change seem to be highly affected by the presence of different surfactants.

[0097] As shown in FIGURE 6B, other pH indicator dyes (MR, PR, and BTB) showed a similar behavior.

[0098] Example 7. Alginate Hydrogels with BCP pH Indicator Using Artificial Saliva (AS) to Induce Color Change for The Detection of Cavities

[0099] This Example evaluated, inter alia, the BCP color change in an alginate hydrogel format using artificial saliva as the color change inducing medium at different starting hydrogel pHs / color. A 0.3 mM solution of BCP in UPW was prepared with a final pH of 3.6. A hydrogel composed of 67 wt% BCP solution (0.3 mM); 13 wt% sodium alginate; and 20 wt% microcrystalline cellulose, was well mixed to form a homogeneous hydrogel (purple color). The initial hydrogel had a strong purple color; the color of the hydrogel was adjusted using small quantities (10-30 pL) of pH 1 and pH 2 HC1 solutions. The hydrogels (0.3-0.6 g) were exposed to 10 pL AS at different pHs (6.8, 6.1, 5.2, 4.5).

[0100] As shown in FIGURE 7, for the hydrogels with a purple color, a color change from purple to yellow was easily detected when the AS pH was below 5.5. No color change was observed with AS pHs above 5.5 for the same purple hydrogels. For the hydrogel with a dark yellow color, a color change from yellow to purple was easily detected when the AS pH was above 6.0. While no color change was observed with AS pHs below 6.0 for the same yellow hydrogel. Hydrogels that were exhibiting a light-yellow color showed no color change.

[0101] Example 8. Alginate Hydrogels Containing Artificial pH Indicators in a Tray Format for the Detection of Cavities Utilizing 3D Printed Dental Models.

[0102] This Example evaluated, inter alia, development of tray prototypes to imprint dental models with artificial saliva at different pHs and study color change and mechanical properties of the prototypes.

[0103] For BCP, a 0.3 mM solution of BCP in UPW was prepared with a final pH of 3.6 An 8 g hydrogel composed of 67 wt% BCP solution (0.3 mM); 13 wt% sodium alginate; 20 wt% microcrystalline cellulose was well mixed to form a homogeneous hydrogel (purple color). The hydrogel material was placed onto a thermoplastic tray support. A 3D printed dental model was imprinted into the gel, and the gel was exposed to 2 pL AS of different pHs at different locations. The color change of the gel was monitored for 45 min.

[0104] For MR, a 0.1 mM solution of MR in UPW was prepared with a final pH of 7.0. An 8 g hydrogel composed of 67 wt% MR solution (0.1 mM); 13 wt% sodium alginate; 20 wt% microcrystalline cellulose, was well mixed to form a homogeneous hydrogel (yellow color). The hydrogel material was placed onto a thermoplastic tray support. A 3D printed dental model was imprinted into the gel, and the gel was exposed to 2 pL AS of different pHs at different locations. As shown in FIGURE 8A, a color change from purple to yellow was easily detected when the AS pH was below 5.5. No significant color change was observed with AS pHs above 5.5. In FIGURE 8B, a color change from yellow to red was detected when the AS pH was below 5.5. No significant color change was observed with AS pHs above 5.5.

[0105] Example 9. Wax and Siloxane Materials Containing Artificial pH Indicators Using Artificial Saliva (AS) to Induce Color Change for the Detection of Cavities

[0106] This Example evaluated, inter a a, the incorporation and color change behavior of synthetic pH indicator dyes into wax-based and siloxane-based materials.

[0107] For wax-based materials, 0.5 g of a dental wax and 2 wt% of a synthetic pH indicator (BCP) were combined and mixed manually. The colored wax material was exposed to 5 pL AS of different pHs: 6.8 and 4.5.

[0108] For siloxane-based materials, 0.5 g of a dental siloxane base material and 2 wt% of a synthetic pH indicator (BCP) were combined and mixed manually. The colored siloxane material was exposed to 5 pL AS of different pHs, 6.8 and 4.5.

[0109] As shown in FIGURE 9, the wax-based and siloxane-based materials containing BCP showed a clear leaching of the BCP pH indicator from the material to the AS. The leached BCP clearly changed color according to the pH of the AS. pH 6.8 showed a dark purple color and pH 4.5 showed a yellow color.

[0110] Example 10: Two-Component Material

[0111] This Example evaluated, inter alia, a two-component material comprising 1 ) a mixture containing at least a polysaccharide, a divalent salt, and a filler, and 2) an aqueous solution. The materials comprise at least a sensing agent and other ingredients in either of the component. These experiments show how when the two components are mixed well to prepare a paste, which can be loaded on a tray to contact the teeth in multiple areas, there is an observed change to stiffer consistency or not. In these experiments, mixture 1) contained alginate (0.75g), calcium sulfate dihydrate (1.5g), and celite (1.5g), and 2) the aqueous solution contained water (6 ml), Bromocresol purple (BCP) (1.62 mg or 0.5mM), and sodium pyrophosephate (0.1 g). The two components were mixed well to prepare an impression paste, which was then loaded on a tray to take a dental impression with a mixing time of 45 seconds, a working time of 1-2 minutes, and a setting time of < 60 seconds. FIGURE 10 shows the two-component material, after being mixed and loaded in a tray, and an impression was then taken with the dental set. FIGURE 11 shows how, after setting, the materials demonstrate a color change with a pH 5.1 saliva, but no color change with a pH 6.6 saliva.

[0112] Example 11: Gum-Based Material

[0113] This Example evaluated, inter alia, gum-based material comprising as least a thermoplastic polymer, a sensing agent, a fdler and other components. These experiments show how gum-based material was able to deform and contact multiple teeth and tooth surfaces with or without a tray. In these experiments, the gum-base formulation was the following: Cordo T (a polymer / filler / additive mixture) at 2 grams; microcrystalline cellulose at 0.5 grams; celite at 0.5 grams; bromocresol purple (BCP) at 1 milligram, water in a volume of 2 milliliters, and a NaOH solution (0.1M) at 1 milliliter. As shown in FIGURE 12, gum-based materials demonstrate a color change after being impressed with a dental set pre-wetted with a pH 5.1 saliva. No color change if the area is pre-wetted with a pH 6.6 saliva.

[0114] EQUIVALENTS

[0115] While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth and as follows in the scope of the appended claims.

[0116] Those skilled in the art will recognize, or be able to ascertain, using no more than routine experimentation, numerous equivalents to the specific embodiments described specifically herein. Such equivalents are intended to be encompassed in the scope of the following claims.

[0117] INCORPORATION BY REFERENCE

[0118] All patents and publications referenced herein are hereby incorporated by reference in their entireties. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention.

[0119] As used herein, all headings are simply for organization and are not intended to limit the disclosure in any manner. The content of any individual section may be equally applicable to all sections.

Claims

CLAIMSWhat is claimed is:

1. A device for detection of a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, and / or cavity activity risk and / or demineralization and / or cavity demineralization risk, and / or caries risk, or precursor thereof, comprising:(a) a carrier, selected from a tray, a sticker, or a paper made holder, comprising a substrate attached to or layered thereto and being suitable for comprising a sensing agent, wherein: the carrier contacts or is suitable for contacting a plurality of surfaces of one or more teeth; and the substrate is or comprises a biologically compatible polymer matrix or biopolymer matrix material; and(b) a sensing agent, the sensing agent being suitable for providing a color change which is indicative of a pH value associated with the presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, caries activity, or precursor thereof, wherein the sensing agent is a synthetic compound, optionally where the synthetic compound is not derived from food.

2. The device of claim 1, wherein the carrier contacts or is suitable for contacting one or more of distal, facial, incisal, lingual, mesial, occlusal, and proximal surfaces.

3. The device of claim 1 or 2, wherein the sensing agent is substantially absorbed into the substrate.

4. The device of any one of claims 1-3, wherein the sensing agent covers substantially the entire external surface of the substrate.

5. The device of any one of claims 1-3, wherein the sensing agent is contained within the substrate.

6. The device of any one of claims 1-3, wherein the sensing agent is applied to the substrate in a monolayer, a bilayer, a solution, or on a surface.

7. The device of any one of claims 1 -6, wherein the substrate is or comprises one or more of a hydrogel, cellulosic, elastomer, hydrocolloid, and / or a malleable organic, non-organic, or a partially organic solid material, and / or one or more of an alginate-based material, gum base, wax, and / or a siloxane-based material.

8. The device of claim 7, wherein the substrate is or comprises alginate.

9. The device of any one of claims 1-8, wherein the substrate further comprises a surfactant.

10. The device of claim 9, wherein the surfactant is a negative surfactant.

11. The device of claim 10, wherein the negative surfactant is sodium lauryl sulfate (SLS).

12. The device of claim 9, wherein the surfactant is a neutral surfactant.

13. The device of claim 12, wherein the neutral surfactant is selected from TWEEN20 (polysorbate 20), TWEEN80 (polysorbate 80), and SPAN80 (sorbitane monooleate, sorbitan oleate).

14. The device of claim 9, wherein the surfactant is a positive surfactant.

15. The device of claim 14, wherein the positive surfactant is ADOGEN464 (methyltrialkyl(C8- C10)ammonium chloride).

16. The device of any one of claims 1-15, wherein the carrier is 3D printed or 3D printable, or other is a polymer based tray, or a sticker or any other type of carrier for a gel or a viscous material that is malleable.

17. The device of any one of claims 1-16, wherein the sensing agent has a high light absorbance.

18. The device of claim 17, wherein the sensing agent has a high light absorbance and is applied to the substrate in a monolayer, a bilayer, a solution, or on a surface.

19. The device of any one of claims 1-16, wherein the sensing agent has a low light absorbance, optionally wherein the sensing agent is applied to the substrate in solution, or on a surface.

20. The device of claim 19, wherein the sensing agent has a low light absorbance and is applied to the substrate in a multilayer, optionally about 3, or about 4, or about 5, or about 6, or about 7, or about 8, or about 9, or about 10 layers.

21. The device of any one of claims 1-20, wherein the sensing agent is a synthetic dye.

22. The device of claim 21, wherein the synthetic dye is a dye of the triphenylmethane family.

23. The device of any one of claims 1-22, wherein the sensing agent is selected from bromocresol purple (BCP), phenol red (PR), bromothymol blue (BTB), methyl red (MR), and bromothymol blue (BTB).

24. The device of claim 23, wherein the sensing agent is bromocresol purple (BCP)25. The device of any one of claims 1-24, wherein the device is suitable for displaying a color change of a first color to a second color that indicates a specific pH value.

26. The device of any one of claims 1-24, wherein the device is suitable for displaying a color change of a first color to a second color that does not indicate a specific pH value.

27. The device of claims 25 or 26, wherein the first color is a primary color.

28. The device of claim 27, wherein the first color is red, yellow, or blue.

29. The device of claim 25 or 26, wherein the first color is a secondary color.

30. The device of claim 29, wherein the first color is orange, green, or violet.

31. The device of claim 25 or 26, wherein the first color is a tertiary color.

32. The device of claim 31, wherein the first color is red-orange, yellow-orange, yellow-green, blue-green, blue-violet, or red-violet.

33. The device of claim 25 or 26, wherein the second color is a primary color.

34. The device of claim 33, wherein the second color is red, yellow, or blue.

35. The device of claim 25 or 26, wherein the second color is a secondary color.

36. The device of claim 35, wherein the second color is orange, green, or violet.

37. The device of claim 25 or 26, wherein the second color is a tertiary color.

38. The device of claim 37, wherein the second color is red-orange, yellow-orange, yellow-green, blue-green, blue-violet, or red-violet.

39. The device of any one of claims 1-38, wherein the device is suitable for displaying a color change of colored to colorless, or substantially colorless, that indicates a specific pH value.

40. The device of any one of claims 1-38, wherein the device is suitable for displaying a color change of colorless, or substantially colorless, to colored that indicates a specific pH value.41 . The device of any one of claims 1-40, wherein the device is suitable for identifying an active caries and / or cavity, or a lack of an active caries and / or cavity.

42. The device of any one of claims 1-41, wherein the pH value is about 5.5.

43. The device of any one of claims 1-41, wherein the pH value is not about 5.5.

44. The device of any one of claims 1-41, wherein the pH value is about 5.5 and indicative of the presence of dental caries, and / or cavity or cavities, or precursor thereof, and / or a risk of developing dental caries.

45. The device of any one of claims 1-44, wherein the pH value is not about 5.5 and indicative of the absence of dental caries, and / or cavity or cavities, or precursor thereof.

46. The device of any one of claims 1-45, wherein the device is suitable for detecting demineralization, optionally of calcium, fluoride, and / or phosphate ions, optionally from enamel and / or dentin, optionally of enamel producing proteins and / or periodontal ligament degrading enzymes, optionally wherein the dentin and enamel producing proteins are selected from collagen and amelogenin, optionally wherein the dentin or periodontal ligament degrading enzyme is collagenase, optionally wherein the periodontal ligament degrading enzyme differentiates between deep and early stage cavities, optionally wherein the device detects demineralization of a catabolic enzyme, and optionally wherein the catabolic enzyme is a protease, sucrase, or sucrose synthase.

47. The device of any one of claims 1-46, wherein the device is suitable for detecting a lack or an absence of demineralization, optionally of calcium, fluoride, and / or phosphate ions, optionally from enamel and / or dentin.

48. The device of any one of claims 1-47, wherein the device is suitable for detecting activity of acid-secreting bacteria, optionally wherein the device increases the activity of acid-secreting bacteria.

49. The device of any one of claims 1-48, wherein the device is suitable for detecting activity of Streptococci mutans, Streptococcus sobrinus. and / or Lactobacilli spp.

50. The device of any one of claims 1-49, wherein the device is suitable for detecting lack of activity of acid-secreting bacteria.

51. The device of any one of claims 1-50, wherein the device is suitable for detecting lack of activity of Streptococci mutans Streptococcus sobrinus and / or Lactobacilli spp., optionally wherein the device detects bacterial acid secretion after intentional activation of bacterial acid secretion, optionally wherein the device increases bacterial acid secretion and / or bacterial activity.

52. The device of any one of claims 1-51, wherein the device is suitable for detecting a dental lesion.

53. The device of any one of claims 1-52, wherein the device is suitable for distinguishing between active and arrested lesions.

54. The device of any one of claims 1-53, wherein the device is suitable for detecting an incipient dental lesion.

55. The device of any one of claims 1-54, wherein the device is suitable for detecting a reversible dental lesion, optionally wherein the device detects the depth of the dental lesion.

56. The device of any one of claims 1-55, wherein the device is suitable for detecting a remineralizable dental lesion.

57. The device of any one of claims 1-56, wherein the carrier is a two-component material comprising 1) a mixture containing at least a polysaccharide, a divalent salt, and a filler, and 2) an aqueous solution.

58. The device of claim 57, wherein the material comprises at least a sensing agent and other ingredients in either of the two components.

59. The device of any one of claims 1-56, wherein the substrate is or comprises a gum based material comprising at least one of a thermoplastic polymer, a sensing agent, a filler and other components.

60. The device of claim 59, wherein the gum based material is able to deform and contact multiple teeth and tooth surfaces with or without a carrier.

61. A method of detecting a presence or absence of dental caries, higher caries risk, and / or cavity or cavities, risk for caries, or caries associated with bacterial acid production, or precursor thereof in a subject, comprising:(a) contacting a surface of one or more teeth with the device of any one of claims 1 -60; and(b) determining a color change in the sensing agent, the color change being indicative of a pH value, and / or other ions or compounds having a concentration adjacent to a specific tooth surface that is associated with the presence or absence of tooth demineralization, dental caries, risk for caries, caries associated bacterial acid production, and / or cavity or cavities, or precursor thereof, and / or risk of developing dental caries, and / or cavity or cavities presence or activity.

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