Method for obtaining porcelain glaze material with antibacterial properties and increased mechanical, aesthetic and microbiological properties used in dental restoration

Abstract

The invention relates to obtaining an Ag / Zn-containing zeolite glaze that is applied to the outer surface of a ceramic (Ips™ e.max press), which is widely preferred today due to its aesthetic properties and used both as a dental restoration material and as a veneering / crowning material, to impart antibacterial properties to the porcelain glaze (coating / glaze) material and improve its mechanical and aesthetic features, thereby protecting the tooth and gingival tissues.

Description

[0001] METHOD FOR OBTAINING PORCELAIN GLAZE MATERIAL WITH ANTIBACTERIAL PROPERTIES AND INCREASED MECHANICAL, AESTHETIC AND MICROBIOLOGICAL PROPERTIES USED IN DENTAL RESTORATION

[0002] Technical Field

[0003] The present invention relates to a restoration material that protects tooth and gum tissues by improving the mechanical properties of, and imparting antibacterial characteristics to, the outer surface (coati ng / glaze) of porcelain / ceramic (Ips™ e.max press), which is widely preferred today for its aesthetic properties and is used both as a dental restoration material and as a veneering / crowning material.

[0004] State of the Art

[0005] In modern dentistry, restorative dental treatment consists of a series of procedures applied to restore the function and aesthetics of decayed, fractured, or worn teeth. This treatment supports overall oral health by preserving or improving the natural appearance of the tooth. However, in the long term, various problems may arise in the teeth of patients who do not maintain adequate oral hygiene. During the procedure, methods such as fillings, crowns, bridges, or implants may be used. Restorative dental treatment improves the patient’s chewing function, ensures harmony between teeth, and enhances smile aesthetics. This process begins with a detailed dental examination and appropriate treatment planning. Restorative dental treatment comprises procedures carried out by means of new technological applications for the repair of enamel loss, removal of caries, and correction of aesthetic alignment. These applications, which meet individual aesthetic expectations, are also frequently used for smile design. In particular, the aim is to achieve proper alignment of enamel layers, maintain the health of the soft tissue surrounding the teeth and gums, and create characteristic designs based on the person's facial shape. In the state of the art, due to the lack of antibacterial properties in the porcelain coating surfaces used, plaque formation and maturation cannot be prevented, especially in patients with poor oral hygiene, leading to gingival inflammation, soft tissue reactions, and the development of caries. For this reason, it has become necessary to conduct R&D studies concerning the impartation of antibacterial properties to the outer surface of ceramic, which serves as a dental coating material, and the protection of tooth and gum tissues.

[0006] In the state of the art, document number WO9907326A2 discloses antimicrobial cement compositions containing antimicrobial zeolites. The preferred embodiments aim to obtain antimicrobial cement compositions for dental applications — including fillers, adhesives, sealants, and restorative materials — as well as for medical applications such as bone cements, implant components, and bone substitutes. A particularly preferred cement is an antimicrobial glass ionomer cement composition intended for use in dentistry, containing a polyelectrolyte, glass ionomer particles, and antimicrobial zeolite particles. The composition is formulated to form a hardened cement, and the glass ionomer particles and zeolite particles are made to form ionic bonds with the polyelectrolyte. The zeolite particles must be present in the composition and on the hardened surface in an amount sufficient to prevent bacterial growth. Preferably, the zeolite contains an antimicrobial metal ion such as a silver ion and is present in the glass ionomer cement composition in an amount ranging from approximately 0.2% to approximately 20% by weight relative to the weight of the glass ionomer particles. Said invention does not involve improving the resistance and antimicrobial properties of a ceramic structure to be used on restorative coatings. Instead, it focuses on working with glass ionomer cement structures.

[0007] In the state of the art, the article titled “Antimicrobial and Mechanical Effects of Zeolite Use in Dental Materials: A Systematic Review” (https: / / doi.Org / 10.15644 / asc55 / 1 / 9) aims to review all existing literature analysing the antimicrobial effects and / or mechanical properties of zeolite as a restorative material in dentistry. It has been suggested that ion-bound zeolite may enhance the antimicrobial properties of dental materials; however, it has also been reported to compromise the mechanical properties of certain materials such as MTA and acrylic resin.

[0008] In the state-of-the-art document number US1 1 179297B2, antimicrobial polymeric compositions containing metal-containing methacrylates are disclosed. To potentiate the antimicrobial effect of cements, it is aimed to incorporate metal-containing methacrylates, such as calcium methacrylate, tin methacrylate, copper methacrylate, and silver methacrylate, either in combination or individually, into biomaterial compositions, particularly those containing methacrylates of metals like calcium and tin.

[0009] Document number US2021261792A1 , also found in the prior art, describes an antibacterial coated product, an antibacterial coating material, a method for producing an antibacterial coating material, and a method for producing an antibacterial coated product. The antibacterial coated product comprises a coating film formed from an antibacterial coating material that comprises at least composite ceramic powders, the material comprising a photocatalytic component, an adsorbent component, a metal component, and a binder on a base material.

[0010] In document EP1749514A1 found in the prior art, a dental composition containing silver is described. The silver-containing ceramic is directed toward an antimicrobial dental composition comprising at least one monomer having at least one ethylenically unsaturated group and a polymerization initiator system. The composition may further include additional components such as a filler, a stabilizer, a UV absorber, a colourant, solvents to adjust viscosity, and the like. The silver-containing ceramic may be a glass powder or a zeolite powder.

[0011] In document WO0137789A1 found in the state of the art, an orthodontic dental appliance is described, which is designed to be placed in the mouth and has an inorganic antimicrobial substance — preferably a zeolite — on its surface. The dental appliance may comprise metal or a polymer, and the substance may be present in a coating applied to surfaces of the appliance that are intended to come into contact with liquids or solids in the oral cavity. The device may be made from a polymer resin or an elastomer containing the substance. A preferred antimicrobial substance comprises ceramic particles containing antimicrobial metal ions, such as silver ions, or zeolite particles.

[0012] Document number JPH1033568A from the prior art describes a separating agent for dental resin moulding production and for producing dental resin moulds using said separating agent. Another document on the same subject, JPH07101791 A, aims to provide a composition with enhanced flame resistance as well as improved antimicrobial and antifungal properties. This composition is obtained by adding at least one silver compound selected from silver chloride, silver nitrate, silver phosphate, silver fluoride, and silver iodide to a refractory material such as clay, agalmatolite, diaspore, bauxite, silica-alumina, or similar. Documents US4412015A and GB2257433A from the state of the art disclose the following: US4412015A describes a dental filling material containing zeolite for dental composites and its manufacturing method. The dental filling material is formed from one or more finely divided inorganic particles selected from barium-containing glass or zeolite crystals. GB2257433A discloses a composite resin for dental use (such as fissure sealants or dentures) or an orthopaedic cement made from chemically or radiation-cured resin. The fillers are in fibre or flat sheet form and include talc, laponite, zeolite, kaolinite, and / or vermiculite.

[0013] Additionally, invention number TR2022 / 020215 in the prior art relates to obtaining an antibacterial dental filling material by adding zeolitic imidazolate framework (ZIF-8) to glass ionomer cement (cement) used in the treatment of dental caries. This treatment involves mechanical removal of caries, elimination of microorganisms, removal of infected dentin, and preservation of carious-affected dentin tissue that is partially demineralised but with an intact collagen matrix and remineralisation potential, as well as reduction of bacterial quantity at the tooth-restoration interface to lower the risk of secondary caries formation.

[0014] Upon examining the state of the art, no development has been observed that provides antibacterial properties and improves the mechanical characteristics of the outer surface (coati ng / glaze) of ceramic (Ips™ e.max press), which serves both as a dental restoration material and as a veneering / crowning material, thereby ensuring the protection of tooth and gum tissues. Therefore, it has been deemed necessary to conduct R&D studies in this field.

[0015] The Aim of the Invention

[0016] The aim of the invention is to improve the antibacterial and mechanical properties of the glaze layer covering the outer surface of the ceramic known as Ips™ e.max press, a dental restoration material widely preferred today for its aesthetic features, by adding Ag / Zn / Zeolite (Ag: silver, Zn: zinc).

[0017] The aim of the invention is to protect tooth and gum tissues by imparting antibacterial properties to the outer surface of ceramic, which serves as a dental coating material. The aim of the invention is the application and improvement of porcelain by adding synthesized Ag / Zn / Zeolite powder to the powder portion of the glaze ceramic in weight ratios of 0%, 1 %, or 2%, followed by testing.

[0018] The aim of the invention is to achieve the highest surface hardness by containing 2% Ag / Zn / Zeolite.

[0019] The aim of the invention is to obtain the highest colour change by containing 2% Ag / Zn / Zeolite.

[0020] The aim of the invention is to reduce surface roughness values by means of the effect of Ag / Zn / Zeolite added to the glaze base.

[0021] The aim of the invention is to provide antibacterial properties to the samples with added Ag / Zn / Zeolite.

[0022] The aim of the invention is to impart antibacterial properties to zeolite A crystals added to the glaze layer by means of ion exchange, through the addition of aqueous solutions of AgNO3and ZnS04salts and the subsequent ion exchange process.

[0023] Description of Drawings

[0024] Figure 1 shows FE-SEM Image of Synthesised Zeolite Crystals

[0025] Figure 2 shows XRD Pattern Graph of Synthesised Zeolite Crystals

[0026] Figure 3 shows Direct Contact Test Results Graph

[0027] Figure 4 shows SEM Image of Biofilm Formation

[0028] Figure 5 shows Evaluation Results Graph of Surface Roughness, Flexural Strength, and Surface Hardness

[0029] Figure 6 shows Colour and Discolouration Test Results Graph

[0030] Detailed Description of the Invention

[0031] The material of the invention was obtained by improving the antibacterial and mechanical properties of the glaze layer covering the outer surface of the ceramic known as Ips™ e.max press a dental restoration material widely preferred today for its aesthetic features through the addition of Ag / Zn / Zeolite (Ag: silver, Zn: zinc). In this study, Ag / Zn / Zeolite powder was added to the powder portion of the glaze porcelain at weight ratios ranging from 0% to 1 % or 1 % to 2%, creating three groups for each test method, and applied to Ips™ e.max press ceramics. To observe the mechanical properties of each control and experimental group sample, Vickers hardness testing, surface roughness measurement with a profilometer, and three-point bending tests were performed. Colour measurements were carried out using a spectrophotometer to observe colour changes related to Ag / Zn / Zeolite and colour stability after immersion in beverages, with comparisons made based on AED > values. The Direct Contact Test method was employed to investigate the antibacterial properties against Streptococcus mutans (S. mutans) in the study groups.

[0032] The surface roughness of the control group was found to be significantly higher than that of the study groups (p < 0.05). While all groups showed statistically significant differences in surface hardness, the highest surface hardness was observed in the group containing 2% Ag / Zn / Zeolite.

[0033] Regarding colour change, each compared group was found to be significantly different from the others (p < 0.001 ), with the greatest colour change observed between the control group and the group containing 2% Ag / Zn / Zeolite. Compared to the control group, fewer bacterial colonies were detected in the culture media of the experimental group samples, and higher antibacterial effects were also observed in biofilm formation within the experimental groups.

[0034] While a decrease in surface hardness values was observed due to the effect of Ag / Zn / Zeolite added to the glaze layer, no significant difference was found in flexural strength, and a reduction in surface roughness values was also noted. The colour changes related to Ag / Zn / Zeolite in the experimental groups remained within acceptable thresholds, and it was determined that the samples containing Ag / Zn / Zeolite acquired antibacterial properties. (Figure - 5)

[0035] The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain used as a dental restoration or veneering / crowning material comprises the process steps of preparing the gel formulation; ageing of the prepared gel for sedimentation and hardening; crystallisation of the aged gel by hydrothermal reaction; washing, centrifugation, and drying of the formed zeolite crystals; preparation of AgNOD and ZnSOD salt solutions; ion exchange by transferring the zeolite powder into the prepared solution; washing, centrifugation, and drying of the resulting Ag / Zn- containing zeolite A crystals; addition of the resulting Ag / Zn / zeolite powder to the glaze porcelain powder; and obtaining a homogeneous glaze mixture.

[0036] In the gel formulation preparation step, the gel prepared is a solution with the composition 1 1 ,25SiOD:1 ,8AlDOD:13.4(TMA)DO:0.6NaDO:7C)OHDO. The ageing step involves a period of 5 hours, during which the chemicals in the wet gel react to form a stable structure. The hydrothermal reaction step involves maintaining the reaction for 8 hours. The washing step for the zeolite crystals consists of washing the crystals three times with distilled water. The centrifugation and drying step involves drying the zeolite crystals in an oven at 60 3. In the salt solution preparation step, 0.2746 grams of AgNOD and / or 3.83 grams of ZnSOD are dissolved in 300 ml of distilled water to prepare the salt solution. In this step, 3 grams of zeolite powder is added to the prepared solution for the ion exchange process. Following the ion exchange process, the formation of zeolite A crystals occurs through a chemical reduction step. The resulting zeolite A crystals are washed three times with distilled water and dried at 45C for 24 hours. The process c omprises adding and mixing 1 % to 2% by weight of the prepared zeolite powder (containing Ag / Zn) into the glaze porcelain powder. The glaze liquid and glaze powder are then mixed to obtain a homogeneous mixture.

[0037] For the preparation of the Zeolite A and glaze (glaze) porcelain content used, zeolite A crystals were synthesised by ageing a gel formulation of 1 1 .25 SiOD :1 .8 Al DOD :13.4 (TMA)DO:0.6 NaDO:700 H DO for 5 hours, followed by an 8-hour hydrothermal reaction. The ageing process refers to the 5-hour period after gel formation during which the wet gel is kept for a prolonged time to allow the chemicals within to react and convert into a stable structure. The aim of ageing is to promote crystallisation. The gel is formed by mixing the silica and alumina solutions given in the formulation, and zeolite synthesis — that is, the formation of zeolite crystals — is carried out by subjecting the gel to hydrothermal treatment. Hydrothermal reactions involve exposing the gel to high pressure and temperature conditions that facilitate crystallisation of normally insoluble substances. As a result of the hydrothermal reaction with aqueous mineralising agents, the gel transforms into crystals.

[0038] At the end of the synthesis, the zeolite crystals are washed three times with distilled water, centrifuged, and then dried in an oven at 60<C. The synthesised crystals shown in Figures 1 and 2 were characterised by Scanning Electron Microscopy (SEM), and the X-Ray Diffraction (XRD) method was used as shown in Figure 3.

[0039] To impart antibacterial properties to the obtained zeolite structure, aqueous solutions of AgNOD and ZnSOD 6HDO salts were prepared. For the ion exchange process in this solution, 0.2476 grams of AgNOD was dissolved in 300 ml of distilled water to prepare the solution. Subsequently, 3 grams of zeolite A and 3.83 grams of ZnSOD were added to the prepared solution. Ion exchange consists of reversible chemical reactions in which an ion bound to a solid material is exchanged with an ion present in the solution. While ions on the solid surface transfer to the solution, ions in the solution attach to the surface of the solid via electrostatic forces. A chemical reduction process was performed to carry out the ion exchange method in the prepared solution. As a result, the ions within the zeolite were converted into nanoparticle form. The zeolite A crystals containing Ag and Zn nanoparticles were washed three times with distilled water and dried at 450 for 24 hours.

[0040] Characterisation of the zeolite crystals containing Ag and Zn was performed using Energy Dispersive X-ray Spectroscopy (SEM-EDX).

[0041] Ips™ Ivocolor Glaze porcelain powder was homogeneously mixed with 1 % to 2% by weight of the zeolite powder containing Ag and Zn. (For each sample, a separate clean brush was used for the control group and other ratio groups in the experiments, and the same volume of glaze mixture was applied.)

[0042] Thus, the ion exchange method was used to impart antibacterial properties to the zeolite A crystals to be added to the glaze layer, and this method enabled the introduction of Ag and Zn nanoparticles onto the zeolite A crystals via aqueous solutions of AgNOD and ZnSOD salts. Following the ion exchange method, chemical reduction was performed to obtain the Ag / Zn / Zeolite structure. The Ag / Zn / Zeolite was added to the powder portion of the glaze porcelain in weight ratios ranging from 0% to 2% and applied to Ips™ e.max press ceramics.

[0043] The prepared sample(s) were fired in a Programat porcelain furnace at a temperature of 770<C. To evaluate the resulting porcelain struc tures, tests were conducted including measurement of surface roughness, surface hardness, and flexural strength; colour measurement tests to observe the effect of zeolite on colour; staining tests; bacterial suspension tests; the direct contact method; and biofilm formation assessment using Scanning Electron Microscopy (SEM) to determine whether the desired results were achieved. Below are the details and groups of the tests applied for evaluation purposes. (Figure - 6)

[0044] Measurement of Surface Roughness of Obtained Ag / Zn / Zeolite Samples

[0045] Surface roughness measurements were performed using a profilometer device with a tip diameter of 5 pm (Surftest SJ-210 Mitutoyo, Tokyo, Japan). The device was calibrated in accordance with the manufacturer’s instructions using the calibration plate included with the device. After calibration, each sample disc was placed sequentially on the device’s standard measurement stage, ensuring the contact angle between the profilometer’s measuring tip and the sample was 90°. Measurements on each sample were conducted by moving the tip at a speed of 2 mm / s over a distance of 4 mm intervals. Three measurements were taken per sample, and the average surface roughness value (Ra) was calculated by averaging the three individual measurements for each sample. The device was recalibrated after every five measurements. Patafix (UHU GmbH & Co. KG), an elastic and reusable adhesive, was used to stabilise the samples during measurement.

[0046] Measurement of Surface Hardness of Samples

[0047] Samples prepared with different zeolite ratios were produced in sets of 10 per group. Microhardness testing was conducted according to ASTM E384-1 1 standard, using a Vickers diamond pyramid indenter. Vickers hardness measurements were performed with a hardness testing device by applying a load of 200 gf for a dwell time of 10 seconds. The Vickers Hardness (HV) value was calculated using the following formula:

[0048] HV = 1 ,8544 x (P / d2)

[0049] (HV: Vickers hardness number, P: load, d: diagonal length) Measurement of Flexural Strength of the Samples

[0050] In accordance with ISO 6872:2008 standards, a three-point bending test was conducted to measure the flexural strength of fully ceramic samples. From each group, 10 rectangular prism-shaped samples with dimensions suitable for Type 1 ceramics as specified by the standards (1.6 mm x 4 mm x 20 mm) were prepared, resulting in a total of 30 samples. The test was performed using a computer-controlled universal testing machine with a capacity of 10 kN (Shimadzu AGS-X, Japan). The distance between the two parallel supports where the samples were placed was set to 16 mm, and the rod-shaped samples with dimensions 1 .6 x 4 x 20 mm were positioned on the device. The device speed was set to 1 mm / min, and force was applied until the samples fractured. The maximum load applied to each sample at the moment of fracture was recorded in Newtons (N), and the flexural strength values were calculated in Megapascals (MPa) by the computer and software connected to the universal testing machine.

[0051] Colour Measurement Test to Investigate the Effect of Zeolite on the Samples’ Colours

[0052] For the colour test, 15 samples with a thickness of 2 mm and a diameter of 10 mm were prepared. Colour measurements were taken using a VITA Easyshade Compact V device (VITA Zahnfabrik, Bad Sackingen, Germany) after the samples were immersed in distilled water at 3713 for 24 hours, t hen dried and placed on a white background under D65 illumination. The device was calibrated before each measurement. During the measurements, the fibre optic tip of the device was positioned perpendicular to and parallel with the samples. Three colour measurements were taken for each sample in both the control and experimental groups, and the averages of the obtained data were calculated. Colour difference was calculated using the CIEDE2000 colour difference formula based on Lab* values.

[0053] Application of Staining Tests

[0054] Two samples from each of the control group and the experimental groups containing 1 % and 2% Ag / Zn / Zeolite were immersed in 15 ml of test solutions in a dark environment at a controlled temperature of 37±10<C for 7 days. The test solutions selected were Coca-Cola, tea (Lipton Yellow Label Tea), and coffee (Nescafe Gold). Tea and coffee were brewed daily according to the instructions on the packaging, the solutions were refreshed daily, and stirred every 12 hours to maintain homogeneity. After the 7-day immersion period, the samples were removed from the test solutions, rinsed with distilled water, and dried with paper towels. The colour of each sample was measured three times before and after immersion in the test solutions, and the averages were recorded. Colour difference was calculated using the CIEDE2000 colour difference formula based on Lab* data.

[0055] Preparation of Bacterial Suspension

[0056] In this study, the standard strain Streptococcus mutans (S. mutans) (ATCC 25175), registered with the American Type Culture Collection (ATCC), was used. The standard strain was removed from storage at -SO'C and allowe d to reach room temperature, then passaged onto brain heart infusion (BHI) agar medium and incubated in a CO2 incubator (Nuve incubator, Turkey) at 35±2<C for 48 -72 hours. Pure colonies grown were then passaged again onto BHI agar medium and incubated under the same conditions for 48-72 hours. From the second passage, 2-4 colonies with pure growth were collected using a sterile loop, homogenised in 4 ml of physiological saline solution, and the suspension was adjusted to a 0.5 McFarland standard (1 x108CFU / mL) using a McFarland device (PhoenixSpec, BD, NJ, USA) through spectrophotometric measurement.

[0057] Application of the Direct Contact Test Method

[0058] Three control discs without zeolite, sterilised with ethylene oxide, were prepared, along with three discs containing 1 % Ag / Zn / Zeolite and three discs containing 2% Ag / Zn / Zeolite, which were placed into microplate wells. Onto each disc in the wells, 10 pl of 0.5 McFarland S. mutans suspension was added, and the plates were incubated in a CO2 incubator at 35±2<C. Colony counts per mil lilitre were determined at 6, 12, 24, and 48 hours.

[0059] Three discs per group were designated for each time point. At 6 hours, 300 pl of BHI liquid medium was added to one control disc, one 1 % Ag / Zn / Zeolite disc, and one 2% Ag / Zn / Zeolite disc, vortexed, and diluted 30-fold to obtain an initial bacterial suspension of 1 x108colony forming units (CFU) per millilitre. For serial dilution, 90 pl of BHI was added to 18 wells on one plate, with six wells allocated for each group using a micropipette. Then, 10 pl was taken from each well containing a disc and transferred into a well containing 90 pl of BHI. Subsequently, 10 pl was taken from this well and transferred into the next, continuing serial 10-fold dilutions from 10-1to 10-6.

[0060] At the end of the test, inoculations were performed from 18 wells representing six different concentrations for each of the control, 1 % Ag / Zn / Zeolite, and 2% Ag / Zn / Zeolite groups. Before each dilution, pipetting was performed to ensure homogeneity of the suspension. From each dilution well, 10 pl was taken and inoculated onto BHI agar plates divided into four quadrants using the drop plate technique. This procedure was repeated at 6, 12, 24, and 48 hours of incubation.

[0061] Bacterial colonies formed after 6, 12, 24, and 48 hours of incubation on the inoculated culture media were evaluated. Results from six different dilutions for each group were used in the evaluation. The number of bacteria in countable dilutions was calculated by multiplying the colony count by the dilution factor, yielding the number of colony forming units per millilitre (CFU / ml).

[0062] Evaluation of Biofilm Formation Differences by Scanning Electron Microscopy (SEM)

[0063] To assess biofilm formation differences after prolonged exposure of zeolite-containing samples and control samples to bacterial inoculum, each test disc was placed into individual microcentrifuge tubes, 300 pl of S. mutans suspension equivalent to 0.5 McFarland standard (approximately 1.5 x 10A8 CFU / mL) in brain heart infusion broth containing 1 % sucrose was added and the samples were incubated for 24 hours, 7 days, and 30 days at ST'C in a 5% CO2 incubator. Af ter incubation, samples were washed with sterile saline for 1 minute to remove planktonic bacteria. For biofilm formation control, samples were fixed in 10% formalin for one week and then dehydrated sequentially with 75%, 90%, and 100% ethanol before examination by SEM. (Figure - 4)

[0064] Significant results were obtained from all these experiments and tests. The mechanical properties, colour, and antimicrobial characteristics of the glaze porcelain coating the exterior of the dental ceramic material marketed as IPS™ e.Max Press were evaluated after firing with zeolite containing silver and zinc added at 0% (control group), 1 %, and 2% by weight. The findings include:

[0065] - A reduction in surface roughness was observed in samples with 1 % and 2% silver and zinc-added zeolite - A decrease in surface hardness was detected in samples with 1 % and 2% silver and zinc-added zeolite

[0066] - The flexural strength of samples with 1 % and 2% silver and zinc-added zeolite was found to have increased compared to the control samples

[0067] - An increase in AE00 values, indicating the colour difference between the samples with 1 % and 2% silver and zinc-added zeolite and the control group, was observed as the zeolite ratio increased

[0068] - An increase in staining caused by cola, coffee, and tea solutions was observed in samples with 1 % and 2% silver and zinc-added zeolite compared to the control group; however, all these values remained below the perceptibility threshold - An increase in antibacterial activity was observed in samples with 1 % and 2% silver and zinc-added zeolite compared to control samples, and it was also found that antibacterial activity increased as the zeolite ratio increased

Claims

CLAIMS1. A method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain used as a dental restoration material or a veneering / crowning material, characterized by comprising; the process steps of: a. preparing the gel formulation, b. ageing the prepared gel for precipitation and hardening, c. crystallising the aged gel by hydrothermal reaction, d. washing the formed zeolite crystals, e. centrifuging and drying, f. preparing the AgNO3 and ZnSO4 salt solution, g. carrying out ion exchange by transferring zeolite powder into the prepared solution, h. washing, centrifuging and drying the formed Ag / Zn-containing zeolite A crystals, i. adding the formed Ag / Zn / Zeolite powder to the glaze porcelain powder, and j. obtaining a homogeneous glaze mixture.

2. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , wherein; the gel prepared in step “a” is a solution of 11 ,25Si02:1 ,8AI203:13,4(TMA)20:0,6Na20:700H20.

3. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , wherein; in step “b,” the ageing time, which allows the chemicals within the wet gel to undergo reactions and transform into a stable structure, is 5 hours.

4. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; the step of ageing the gel in a hydrothermal reaction for 8 hours in the step “c”.

5. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; step of washing the zeolite crystals three times with distilled water in the step “d”.

6. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; step of centrifuging the zeolite crystals and drying them in an oven at GO'C in the step “e”.

7. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; step of preparing a salt solution by dissolving 0.2746 grams of AgNO3 and / or 3.83 grams of ZnSO4 in 300 ml of distilled water in the step “f”.

8. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , wherein; the zeolite powder added in step “g” is 3 grams.

9. The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 or claim 8, characterized by comprising; the step of forming zeolite A crystals through chemical reduction following ion exchange in the step “g”.10.The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; the step of washing the zeolite A crystals three times with distilled water and drying them at 45<C for 24 hours in the step “h”.11.The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 , characterized by comprising; the step of adding zeolite powder containing Ag / Zn at a ratio of 1 % to 2% by weight to the glaze porcelain powder and mixing it in the step “i”.12.The method for obtaining an antibacterial ceramic glaze applied to the outer surface of dental porcelain according to claim 1 or claim 1 1 , characterized by comprising ; the step of mixing the glaze liquid with the powder to obtain a homogeneous mixture in the step “i”.

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