Dental / medical devices containing polydioxanone, use of such devices for tissue reconstruction induction and / or regeneration, and method for manufacturing such devices

Abstract

The present invention relates to a dental / medical device that comprises poly(dioxanone) (PDO or PDS), preferably has an absorbent synthetic film exhibiting a color from white to grey, and is applied in the medical and dental fields. The dental / medical device may have stem cells and graphene used for inducing tissue reconstruction and / or inducing tissue regeneration of bone defects and other connective tissues (such as gingiva, skin, cartilage, cornea, etc.). Further, the present invention relates to the use of the device for the related applications described above and a method for manufacturing the device.

Description

Technical Field

[0001] The present invention relates to a dental / medical device based on poly(dioxanone) (PDO or PDS), preferably having an absorbent synthetic film presenting from white to grey, and applied in the medical and dental fields. The dental / medical device may have stem cells and graphene used for tissue reconstruction and / or regeneration of bone defects and other connective tissues (such as gums, skin, cartilage, cornea, etc.).

[0002] Furthermore, the present invention relates to the use of the device for the above related applications, and a method for preparing the above device.

Background Art

[0003] The principle of guided tissue regeneration (GTR) is based on using a biocompatible membrane to prevent connective tissue and epithelial tissue from moving to the wound, enabling periodontal ligament cells to regrow on the root surface and regenerate the alveolar bone. The membrane suppresses the movement of unwanted cells in tissue regeneration. The use and development of biomaterials for tissue regeneration are very important, especially in the fields of medicine and dentistry.

[0004] Some teachings of the prior art referred to in the present case are described below.

[0005] Christgau, M. "Guided tissue regeneration in intrabony defects using an experimental bioresorbable polydioxanone (PDS) membrane", 2002. Split-mouth trial over 24 months. In this prospective split-mouth trial, radiographic and microbiological findings during the healing process of deep intrabony defects after guided tissue regeneration therapy (GTN) using two types of bioabsorbable membranes were compared. Thirty-one patients with contralateral intrabony defects were randomly treated with an experimental polydioxanone (PDS) membrane and a polylactic acid (PLA) matrix barrier. Each patient had a pair of contralateral deep intrabony defects, proximal periodontal defects with a probing pocket depth (PPD) of 6 mm or more, and radiographic evidence of angular bone defects of 4 mm or more at baseline. At 6 months, 12 months, and 24 months after surgery, the healing outcomes were evaluated by clinical examinations. Specifically, gingival recession (REC), probing pocket depth (PPD), clinical attachment level (CAL), relative vertical attachment gain (V-rAG), quantitative digital radiographic subtraction (amount and area of bone density change), and microbiological analysis. Postoperative membrane exposure occurred at 14 sites in the PDS treatment group and 2 sites in the PLA treatment group. At 6 months, 12 months, and 24 months after surgery, both membranes significantly increased CAL [median: 6 months after (PDS vs PLA: 3.0 mm vs 3.0 mm); 12 months and 24 months after (PDS vs PLA: 4.0 mm vs 4.0 mm)], which corresponded to a V-rAG of 57.1% (PDS) vs 62.5% (PLA) at 24 months after surgery. Sites treated with PDS and PLA showed significant increases in bone density at 6 months, 12 months, and 24 months after surgery. The increase in bone density at 12 months and 24 months after surgery was statistically significantly greater in PDS than in PLA in radiographic analysis. At 24 months after healing, an increase in bone density was observed in 38.8% of the initial defect sites in the PDS group and 41.8% of the initial defect sites in the PLA group, but these differences were not statistically significant. Microbiological culture showed a similar bacterial load in the PDS and PLA sites during the first 12 months.Consequently, although postoperative membrane exposure was expected to be considerably higher at the PDS treatment sites, this 24-month study demonstrated that PDS and PLA membranes achieved similar favorable regeneration results in deep intrabony periodontal defects.

[0006] Dörfer CE et al., "Regenerative periodontal surgery in interproximal intrabony defects with biodegradable barriers", 2000. The effects of guided tissue regeneration (GTR) with two types of biodegradable barriers (polylactic acid acetyl tributyl citrate, polydioxanone - PDS) on intrabony defects were compared. 15 pairs of similar contralateral periodontal defects were provided from 15 patients. Each defect was randomly assigned to treatment with a device of polylactic acid acetyl tributyl citrate (control [c] - Guidor Matrix Barrier, Guidor AB, Huddinge, Sweden) or PDS (test [t] - Mempol, Ethicon GmbH & Co. KG, Norderstedt, Germany). During the healing phase, one patient (PDS) developed an infection on one side. Six months after surgery, clinical measurements: plaque index (PII), gingival index (GI), probing pocket depth (PPD), vertical probing insertion level (PAL-V) were performed. As a result, barrier exposure was commonly observed in both groups (control / test). It was 5 / 4 at 7 days postoperatively, 9 / 11 at 14 days, and 11 / 12 at 28 days. Four weeks after surgery, 77% of all barriers were exposed to some extent. However, in either treatment method, a significant decrease in GI (p < 0.05), a decrease in PPD [-4.63 + 1.85 mm (t), -4.17 + 1.89 mm (c); p < 0.001], and an increase in PAL-V [3.97 + 1.17 mm (t), 3.40 mm + 1.40 mm (c); p < 0.001] were observed 6 months after surgery. No statistically significant or clinically important differences were found between the test group and the control (comparison) group regarding the decrease in GI and PPD, and the increase in PAL-V.

[0007] Eickholz, P. et al., "Guided tissue regeneration with bioabsorbable barriers: intrabony defects and class II furcations", 2000. The authors compared the effects of guided tissue regeneration (GTR) using two different bioabsorbable barriers (control: poly(lactic acid) acetyl tributyl citrate, test: polydioxanone) in 21 patients with 22 pairs of similar contralateral defects (30 intrabony defects and 14 class II furcation lesions). Each defect was randomly assigned to treatment with a control (c) device (Guidor Matrix Barrier) or a test (t) device (Mempol, Ethicon). Clinical measurements such as plaque index (PI), gingival index (GI), probing depth (PD), and vertical and horizontal clinical attachment loss (CAL-V; CAL-H), and standardized radiographs were obtained at baseline and 12 months postoperatively. As a result, barrier exposure was commonly observed in both groups. At 4 weeks postoperatively, 61% of all barriers were slightly exposed. However, in both treatment methods, at 12 months postoperatively, in all defects, a significant decrease in GI (P < 0.005), a decrease in PD (-3.08 ± 2.29 mm [t]; -3.52 ± 2.67 mm [c]; P < 0.001), and an increase in CAL-V (2.44 ± 2.29 mm [t], 2.80 ± 2.21 mm [c]; P < 0.001) were shown. In intrabony defects, bone filling was significant (2.03 + / - 1.70 mm [t]; 1.91 + / - 1.20 mm [c]; P = 0.001), and in furca lesions, although slight, a significant increase in CAL-H was observed (0.79 + / - 0.68 mm [t]; 1.13 + / - 1.44 mm [c]; P < 0.05). In the analyzed data, no statistically significant or clinically important differences were found between the test group and the control group at 12 months postoperatively.

[0008] Kim, T. S., "Comparison of two types of synthetic biodegradable barriers for GTR in interproximal intrabody defects: clinical and radiographic 24-month results", 2003. This study compared the effectiveness of tissue regeneration induction (RTG) using poly(lactic acid) acetyl tributyl citrate and polydioxanone (PDS) in 3-wall and 2-wall intrabony defects. Fifteen patients provided 15 pairs of similar contralateral periodontal defects. There were 12 mainly 2-wall intrabony defects and 18 mainly 3-wall intrabony defects. Each defect was randomly assigned to treatment with poly(lactic acid) acetyl tributyl citrate (control - Guidor matrix barrier) or a polydioxanone device (test - Mempol). Clinical measurements were taken at baseline, 6 months, 12 months, 18 months, and 24 months postoperatively, and standardized radiographs were obtained (not obtained after 18 months). In both treatments, a significant reduction in gingival index, a reduction in probing depth, and an increase in the insertion level of vertical probing were observed at 24 months postoperatively. Slight alveolar bone crest resorption was observed in both treatments at 24 months, but no statistically significant difference was reached. In both treatment methods, the increase in bone in the intrabony pocket at 24 months was statistically significant. No statistically significant or clinically relevant differences were seen between the test barrier and the control barrier with respect to the reduction in gingival index and probing depth, and the vertical probing insertion level and bone augmentation. The use of both biodegradable barriers in GTR treatment can be recommended.

[0009] Eickholz, P., "Guided tissue regeneration with bioabsorbable barriers. II. Long-term results in infrabony defects", 2004. The aim of this five-year randomized controlled clinical trial was to evaluate the long-term outcomes of guided tissue regeneration (GTN) treatment of intrabony defects using two types of absorbable barriers. In this study, 15 patients with a pair of contralateral intrabony defects and moderate to severe periodontitis were included. Each patient was randomly assigned to receive polydioxanone (test: T) and acetyl tributyl citrate polylactide barrier (control: C). Clinical parameters and standardized radiographs were obtained at baseline, 12 months after surgery, and 60 ± 3 months after surgery. Vertical bone level (PBL-V) was measured by transgingival bone probing during surgery and at 60 ± 3 months after surgery. Thirteen patients were able to participate in the 60-month examination. The vertical insertion gain (CAL-V) observed at 12 months and 60 ± 3 months after GTR was statistically significant in both groups (P ≤ 0.001) (T12: 3.5 ± 1.5 mm, T60: 2.2 ± 1.8 mm, C12: 4.0 ± 0.8 mm, C60: 2.0 ± 0.8 mm). However, from 12 months to 60 months after treatment, CAL-V decreased significantly in both groups (P < 0.05). Compared with the review at 12 months, CAL-V decreased by more than 2 mm in 2 defects in the test group and 3 defects in the control group. At 12 months and 60 ± 3 months after surgery, the bone filling measured by radiographs was statistically significant in both groups (P < 0.05) (T12: 1.2 ± 1.3 mm, T60: 1.5 ± 2.2 mm, C12: 0.9 ± 1.4 mm, C60: 1.0 ± 1.6 mm). Furthermore, the increase in PBL-V observed in both groups at 60 months after surgery (test group: 1.8 ± 2.3 mm, control group: 2.2 ± 1.8 mm) was significant (P < 0.05). There was no statistically significant difference between the test group and the control group regarding the increase in CAL-V and PBL-V at 60 months after surgery. In conclusion, the CAL-V gain achieved after GTR treatment of intrabony defects using both absorbable barriers was stable after 5 years in 21 out of 26 defects (81%).

[0010] Pretzl, B., "Guided tissue regeneration with bioabsorbable barriers III 10-year results in infrabony defects", 2009. This paper evaluated the 10-year outcomes after the treatment of intrabony defects with two types of bioabsorbable barriers in a randomized controlled trial. In 15 periodontitis patients, 15 pairs of intrabony defects were treated. For each patient, one defect was randomly assigned to receive a barrier of polydioxanone (test: T), and the other to receive a barrier of poly(lactic acid) tributyl citrate (control: C). Clinical parameters and standardized radiographs were obtained at baseline, 12 months after surgery, and 120 ± 6 months after surgery. Only 9 out of the initial 15 patients participated in the 120-month examination. The increases in the vertical probe insertion level (PAL-V) observed in both groups at 12 months (T12: 3.9 ± 1.6 mm, T120: 2.4 ± 1.8 mm, C12: 4.0 ± 1.1 mm, C120: 2.4 ± 1.7 mm) and 120 ± 6 months after treatment were statistically significant (p ≤ 0.004). From 12 months to 120 months, both groups experienced a loss of PAL-V (T: 1.4 ± 1.5 mm, p = 0.021; C: 1.6 ± 2.5 mm, p = 0.09). At 120 months, two teeth were lost in the control group (one due to pericoronitis of a wisdom tooth and the other of unknown cause). In this study, no statistically significant difference was found between the two groups regarding the PAL-V gain at 120 months postoperatively.

[0011] Document US2020 / 0330641 discloses a suture membrane composed of graphene oxide (due to biocompatibility, bacteriostatic action, and hydrophilicity) and a polymer. In this document, electrospinning technology is used for the production of polymer fibers. Furthermore, in this document, a biodegradable fibrous biocomposite membrane composed of graphene oxide can also be surgically used as a medical dressing, a surgical suture, and a drug carrier.

[0012] Document KR 101636778 discloses a method for manufacturing a biodegradable nanofiber sheet for tissue regeneration. In this document, graphene oxide is used. Graphene oxide plays an important role in cell growth and differentiation due to its properties, especially hydrophilicity and flexibility. In this document, electrospinning technology is used to generate graphene oxide fibers and synthetic polymers or natural polymers are used to support tissue regeneration. Among these polymers, there is polydioxanone.

[0013] Document CN105126167 describes the repair and reconstruction of bone tissue. In particular, it describes a method for preparing and supporting a biological coating that functionalizes the surface of a 3D printed titanium-based porous alloy for bone tissue repair and reconstruction. The 3D printed metal-based functionalized porous frame is provided with a functionalized bioactive nanocomposite coating on the surface of oxidized fibroin-graphene silk. Also, in this document, polymers such as polydioxanone are also adopted.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0014] As described above, in the prior art, there is no solution equivalent to the one that combines the technical differences, economic advantages, safety, and reliability as presented in this specification of the present invention.

[0015] Therefore, an object of the present invention is to provide a device for use in the reconstruction and / or induction of tissue regeneration of bone defects and other connective tissues (such as gums, skin, cartilage, cornea, etc.).

[0016] Another object of the present invention is to provide a single-use dental / medical device that is supplied in a sterile state and is available in various models and dimensions.

[0017] Another object of the present invention is to provide a solution means adapted to patients who require tissue reconstruction induction and / or regeneration of bone defects and other connective tissues (such as gums, skin, cartilage, cornea, etc.).

[0018] Furthermore, an object of the present invention is to provide a solution means that is gradually resorbed in the body and replaced with newly formed bone tissue and / or soft tissue (gum, skin, cartilage or cornea) during the process of repair or tissue regeneration induction.

[0019] An object of the present invention is to provide a solution means having sub- and micrometer fibers, mechanical and biological barriers, with a morphology and surface topography mimicking the extracellular matrix.

[0020] An object of the present invention is to provide a solution means that can be used in various types of surgeries and applications in the field of orthopedic medicine, such as dura mater reconstruction, periosteum replacement, yellow ligament replacement (spine), mechanical barrier for graft maintenance, biological barrier in transplantation techniques, trauma, bone tissue reconstruction, bone tissue coating after bone spine removal, reconstruction of defects or cranial closure, and having physical-mechanical and biological barrier functionality.

[0021] An object of the present invention is to provide a product exhibiting functional and mechanical properties that satisfy the intended use.

[0022] An object of the present invention is to provide a product that mimics the extracellular matrix of connective tissue and provides mechanical strength for efficient handling and high absorbency of liquids and molecules.

Means for Solving the Problems

[0023] The present invention achieves the above and other objects by a dental / medical device particularly used for inducing and / or regenerating tissue reconstruction of bone defects and other connective tissues. This dental / medical device has an absorbent synthetic membrane containing poly(dioxanone). This membrane has a substantially rectangular cross-section, with a thickness varying between 0.05 mm and 2.00 mm, a width varying between 15 mm and 200 mm, and a length varying between 20 mm and 200 mm.

[0024] The present invention achieves the above and other objects by using the device for inducing tissue reconstruction (regeneration) of bone defects and other connective tissues (e.g., gingiva, skin, cartilage, and cornea).

[0025] Furthermore, the present invention achieves the above and other objects by a method for preparing the device of the present invention, which includes the following steps. That is, the method a. placing the raw materials in a vacuum oven at room temperature; b. weighing the raw materials to prepare a solution with an organic solvent; c. an operator inserting a program suitable for the operation to set up the machine; d. after injecting the polymer solution into the machine, operating the machine to produce a membrane at a predetermined flow rate; e. taking out the membrane blanket and placing it in a vacuum oven for removing the residual organic solvent; f. sending the blanket to a CO2 laser cutting machine to perform a membrane cutting process; g. storing the membrane in a sealed container; h. individually packaging the membrane and the like.

Brief Description of Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0027] The present invention will be described based on the accompanying drawings.

[0028] In a first preferred embodiment, the present invention relates to a dental and / or medical device comprising a polydioxanone membrane. Further, the membrane has sub- and micrometer fibers whose physicochemical and morphological properties promote the diffusion of biological fluids and cell adhesion.

[0029] Therefore, the device of the present invention will be used, for example, for the reconstruction of bone defects and other connective tissues (such as gingiva, skin, cartilage or cornea, etc.) and / or for inducing tissue regeneration.

[0030] The device of the present invention has a membrane prepared from poly(dioxanone), a resorbable alloplastic material. This type of material is suitable for bone repair because it is replaced simultaneously with the newly formed tissue. Thus, the device of the present invention can be used as a mechanical barrier for maintaining the defect space and as a mesh for the augmentation / reconstruction of bone tissue and soft tissue. Due to the physical structure and composition of the membrane, absorption can be controlled within a period estimated to be 3 to 12 months.

[0031] Therefore, the membrane is a synthetic resorbable poly(dioxanone) and has a mesh-like microstructure that functions as a mechanical barrier for promoting space maintenance and efficient tissue repair or regeneration processes.

[0032] The decision to use absorbent polymers is based on the following facts. That is, heterogeneous natural polymers are generally difficult to handle, have physicochemical properties that are difficult to control batch by batch, have a degradation rate that is difficult to change, and their purification and sterilization are not simple. In addition, heterogeneous natural polymers have a high risk of cross-contamination from the source of raw materials (pathogens and viruses), and a high possibility of immunoreactivity due to the presence of proteins produced in other biological species. Furthermore, it has already been reported that a severe local inflammatory reaction is induced after the use of a collagen membrane.

[0033] The device of the present invention is for single use (disposable), is supplied in a sterile state, and is available in various designs and dimensions.

[0034] The device of the present invention is preferably provided in the following dimensions. That is, the thickness ranges from 0.05 mm to 2.00 mm, the width ranges from 15 mm to 200 mm, and the length ranges from 20 mm to 200 mm.

[0035] The present invention is preferably formed by filaments having a diameter between 500 nanometers and 2 micrometers.

[0036] Furthermore, as shown in the following table, the present invention is manufactured by electrospinning, which imparts higher resistance in relation to the PDS plate process that is molding / injection, thus bringing about a technical difference.

[0037]

Table 1

[0038] In a second preferred embodiment, the present invention has graphene, or other compounds made of carbon (nanocarbon, carbon nanotubes, etc.). The presence of these compounds adds mechanical strength to the device of the present invention and imparts antibacterial properties.

[0039] In a third preferred embodiment, the present invention includes stem cells. These stem cells are preferably autologous adult mesenchymal stem cells obtained from a patient's skin punch (dermal punch).

[0040] In a fourth preferred embodiment of the present invention, the present invention has graphene and stem cells. This embodiment is shown in FIG. 5. In human adipose-derived stem cells (hASCs), after 11 days of differentiation, cartilage differentiation fiber coating and morphological changes were observed on both evaluation membranes, and significant structural organization was observed in the present invention.

[0041] Multiple embodiments of the present invention containing stem cells have the following characteristics. - Being a customized product, - Using adult mesenchymal stem cells derived from adipose tissue (which is obtained from a skin punch, an easily accessible source / immunomodulatory effect / promotes the regeneration process), - Flexibility of use (dental and / or orthopedic surgery), - By using stem cells, it is possible to use the device of the present invention not only for cartilage regeneration but also for the regeneration of other tissues such as bone tissue.

[0042] Use of the device according to the present invention This device must be applied to foreign patients or in a hospital environment.

[0043] The techniques for using and applying the device according to the present invention vary according to the preference of the surgeon (physician or dentist). The selection of things such as the therapeutic approach, model and dimensions of the product, application technique, use of fixation or complementary biomaterials, and the criteria for monitoring and evaluating the surgical results are left to the surgeon.

[0044] Proper preparation of the recipient bed (recipient bed) includes treating the entire area to be covered by the device. The cavity and / or bone tissue or soft tissue and the implantation site must have a uniform surface and the final shape of the desired recipient bed that has already been prepared, and bleeding must also be controlled. This allows the device to perfectly adapt to the recipient bed and achieve the expected results.

[0045] In the operation and implantation procedure of the device of the present invention, the surgeon should only use appropriate and sterilized surgical instruments. Also, prior to the surgical procedure, the surgeon (physician or dentist) must perform a rigorous preoperative plan through clinical examinations and imaging examinations (radiographs or computed tomography). Also, the need for a detailed anamnesis and additional examinations regarding the general health status of the patient (complete blood count, coagulation profile, calcium dosage, etc.) should also be considered. Because this information directly affects the biological response of the living body to the installation of the device of the present invention. Moreover, it is necessary to determine a preoperative surgical plan including the selection of the most suitable model and size of the device for the patient's condition.

[0046] The surgical protocol must be carried out according to the surgeon's references and past experience. At that time, always consider the optimal selection of the device model and size, technique, installation order, use of fixation methods (sutures, staples, screws), etc., and always be based on the conventionally established treatment techniques for tissue regeneration induction and bone grafting.

[0047] The present invention presents a number of technical and economic advantages when compared with the prior art, some of which are listed below. - The device of the present invention guarantees a high swelling efficiency. - The device of the present invention acts as a mechanical barrier that promotes space maintenance and efficient tissue regeneration induction. - The device of the present invention has a morphology and surface shape similar to the extracellular matrix, and its physicochemical and morphological properties promote the diffusion of biological fluids and cell adhesion. - The device of the present invention is designed and manufactured to ensure safety and effectiveness regarding systemic toxicity. - The device of the present invention is safe and effective in terms of biocompatibility. Its characteristics, performance, and functionality are guaranteed by physicochemical analysis and preclinical trials. - It is an absorbable product, and according to trace element identification tests and gel permeation chromatography, there is no risk due to the substances released therefrom. - The device of the present invention is designed and manufactured to eliminate risks related to temperature conditions and guarantee the integrity of the product during its effective period. - The synthetic membrane reduces the risks of cross - contamination and immunoreactivity. - The present invention is a tissue regeneration - inducing device applicable to intrabony defects resulting from congenital, post - traumatic, post - surgical problems, or diseases such as periodontal disease and perimplant lesions. - The present invention promotes the augmentation / reconstruction of alveolar bone ridge associated with bone grafts or synthetic bone substitutes for tissue regeneration induction.

[0048] The present invention acts as an advantageous barrier for maintaining the space of the bone cavity or the space formed for the augmentation of the alveolar bone ridge.

[0049] In a preferred embodiment of the present invention, a dental / medical device particularly used for tissue regeneration induction and / or regeneration of bone defects and other connective tissues (including gingiva, skin, cartilage, or cornea) has graphene (reduced graphene oxide). The structural differences of this preferred embodiment can be observed in Figure 1 as compared with Figure 2. The device preferably has graphene, preferably reduced graphene oxide, in a concentration range of 0.52% to 1.35%.

[0050]

Table 2

[0051] Also, it is possible to observe the structural differences in these concentrations in FIG. 3. In FIG. 3, (A) shows the present invention having 0.52% reduced graphene oxide, (B) shows the present invention having 0.71% reduced graphene oxide, and (C) shows the present invention having 1.35% reduced graphene oxide.

[0052] As a result, when reduced graphene oxide was added to the present invention, the control membrane (control film) showed the highest elongation stress and the lowest deformation, which was advantageous for fracture.

[0053] Test 1. Physical and Mechanical Property Evaluation Mechanical tests were conducted based on ASTM D882:2012 - Standard Test Method for Tensile Properties of Thin Plastic Sheets. Test specimens were prepared with dimensions of 50 mm × 10 mm in the longitudinal direction of the mesh. Ethylene oxide (EtO)-sterilized or non-sterilized test specimens (n = 5 from each lot) were tested on an Instron 5569 universal testing machine equipped with a 500 N load cell at a speed of 50 mm / min-1 under conditions of 23 °C and 50% R.H. According to the obtained results, it was found that sterilization with EtO did not change the mechanical properties of the membrane and was satisfactory for this product. In addition, according to the results found in the literature related to collagen membranes, the device of the present invention showed tensile strength equal to or higher than those of the tests conducted with Bio-Gide (Geistlich), Jason (Botiss), and BioMend (Zimmer) (1), and showed better elongation at break than all collagen membranes existing in the domestic and international markets (1-3). Regarding the PDS membrane of Johnson & Johnson, it was shown that the mechanical properties of the device according to the present invention were superior compared to the literature data (2).

[0054] 2. Chemical / Substance Property Evaluation Trace Elements The methods used for the tests and reference parameters are based on the standards ISO 10993-1, ISO 10993-17, ISO 10993-18, and ABNT NBR ISO 13175-3:2013. These standards are commonly used for the characterization of calcium phosphates for medical applications, considering that the total amount of heavy metals in the product is the sum of the following elements. The following elements are lead, mercury, bismuth, arsenic, antimony, tin, cadmium, silver, copper, and molybdenum. As a result, for all the analyzed elements, the values were shown to be below the quantification limit (LQ) of the equipment. The batch showed the acceptable levels of trace elements defined in ABNT NBR ISO 13175-3:2013.

[0055] 3. Swelling ratio according to ASTM 570 To measure the swelling ratio, five samples were prepared for each thickness (0.25 mm, 0.5 mm, and 1.0 mm) of the device of the present invention. The values obtained in the experiment were such that, with respect to the dry mass of each type of membrane after 24 hours of immersion, the average swelling ratios of the 0.25 mm and 0.5 mm membranes were 436.55 ± 22.62% and 425.23 ± 14.99% respectively, and the average swelling ratio of the device with a thickness of 1 mm was 239.46 ± 11.54%.

[0056] As a result, in the thin membranes (0.25 and 0.5 mm), the swelling ratio was maximum in the first minute of immersion, in the 1 mm thick membrane, the swelling stabilized after 2 hours, and in the 0.5 and 0.25 mm thicknesses, it showed an average of 400% with respect to the dry weight, and in the 1 mm thickness, it showed a maximum swelling ratio of 200%.

[0057] 4. Scanning electron microscope The SEM images show a morphological structure in which submicron-order fibers are randomly woven. Laser cutting was proven to be effective in the images obtained by SEM, and the images revealed that the difference in the morphology of the membrane in the regions far and near the laser cutting site was limited to a width on the order of 30 μm.

[0058] 5. DSC (Differential Scanning Calorimetry) Differential Scanning Calorimetry (DSC) was performed by analyzing the DSC curve of the sample (without sterilization) using an aluminum sample holder with a cap. The sample was subjected to the following temperature program. That is, it was heated from -10°C to 120°C at 10°C / min, isothermal at 120°C for 5 minutes, cooled from 120°C to -10°C at 10°C / min, isothermal at -10°C for 5 minutes, and heated from -10°C to 350°C at 10°C / min. This cycle was carried out under a dynamic atmosphere of nitrogen gas (N2) with a flow rate of 50 mL / min. The experiment was carried out using a Netzsch model DSC 214 Polyma device in accordance with ASTM D3418:2015. As a result, the samples of the non-sterilized device of the present invention showed satisfactory results regarding thermal properties. The data on the melting temperature and crystallization temperature of the obtained product supported the literature data (4,5) of the PDO polymer.

[0059] 6. Product Integrity According to the results shown in reports AFK01834 / 20, AFK0476 / 21, and AFK0653 / 21, the samples of the device of the present invention tested always obtained satisfactory results for the degree of crystallinity (%Xc), similar to the literature data. The values obtained for the degree of crystallinity (average value and standard deviation, T1 = 49 ± 1.4%Xc; T2 = 44 ± 0.8%Xc; T3 = 50 ± 0.94%Xc) are acceptable values and are within the range determined by the design for the intended use (40 - 60%Xc) in a way that does not compromise its effectiveness (subject to being stored under appropriate temperature conditions). The manufactured samples showed stability and reproducibility up to 12 months among each triplicate.

[0060] 7. Maximum Percutaneous Sensitization The Maximized Dermal Sensitization assay consists of analyzing the ability of a substance to cause an immunologically mediated skin reaction to the substance, characterized by the appearance of edema and / or erythema. The maximization method uses an adjuvant (Freund's Complete Adjuvant - FCA) that can stimulate the immune response to increase the sensitivity of the method. Since it is a solid, the device of the present invention had to undergo an extraction process for inoculation (see ISO 10993-12: Sample preparation and reference materials, 2012). For this purpose, the device was extracted for 72 hours at 37 °C and 100 rpm in a shaker incubator at a ratio of 6 cm² of membrane area per 1 mL of 0.9% sodium chloride solution. The liquid (extract) obtained in this process showed a homogeneous and colorless appearance. After extraction, a test was conducted using guinea pigs (Cavia porcellus - Dunkin Hartley), in which extracts of the control (reference substance) and the test substance were diluted and intradermally injected, and these products were further exposed to the skin. As a result, no skin reaction was observed in the experimental group and the control group, and the test was terminated. Thus, according to the method applied in accordance with ISO 10993-10 (Tests for irritation and skin sensitization of Biological evaluation of medical devices), the test substance was found to be non-sensitizing.

[0061] 8. Reactivity in the skin The Intracutaneous Reactivity test evaluates the local side effects that occur after percutaneous inoculation of a substance in a single dose. Since the device of the present invention is a solid, it was necessary to go through an extraction process for inoculation (see ISO 10993-12: Sample preparation and reference materials, 2012). The test was conducted using randomly selected rabbits (Oryctolagus cuniculus - New Zealand). Approximately 24 hours before administering the test substance, the back was shaved in an area of about 10 x 15 cm. After shaving, the back of the animal was divided into a test area and a control area using an underwater pen, and 0.2 mL per site, for a total of 1 mL of the device extract (test substance), was administered intradermally at 5 sites in the test area. The extraction vehicle (0.9% sodium chloride) was applied to the control site under the same conditions as the application of the device. The application sites were evaluated at 24, 48, and 72 hours after application and classified according to the presence or absence of edema and erythema. As a result, none of the animals showed edema or erythema at either the application site (test) or the control site (0.9% sodium chloride). Therefore, according to the method applied in accordance with ISO 10993-10 (Biological evaluation of medical devices - Tests for irritation and skin sensitization), the test substance was found to be satisfactory.

[0062] 9. Acute systemic toxicity Acute systemic toxicity is the evaluation of the health risks and adverse effects that may occur as a result of a single exposure to a substance. These tests provide information on systemic toxic effects and form the basis for estimating the safety of the substance. The tests conducted are based on ISO 10993-11: Biological evaluation of medical devices - part 11: Tests for systemic toxicity (2006) and its 2017 update. Since it is a solid substance, according to ISO 10993-12: Sample preparation and reference materials, 2012, the test substance had to be extracted with 0.9% sodium chloride solution and inoculated. The test substance extract was intravenously administered at a dose of 50 mL per kg of animal body weight, and the extraction medium was administered to 10 mice (Mus musculus - Swiss) in the control group under the same conditions as the test substance. After application, the presence or absence of toxic signs was regularly observed at 1, 24, 48, and 72 hours. Toxic signs include changes in the skin, eyes, respiratory system, circulatory system, and digestive system, changes in motor activity, salivation, convulsions, piloerection, weight loss, and death. The test substance was evaluated according to pharmacopoeial standards. According to these standards, if all animals survive and show no clinical signs of toxicity, the test substance is considered to meet the adopted requirements. After the test, no signs of systemic toxicity or death were observed in the test group, so there was no need for gross autopsy to evaluate toxicity. Therefore, according to the method applied in accordance with ISO 10993-11: Biological evaluation of medical devices - Tests for systemic toxicity, the test substance was found to be satisfactory.

[0063] 10. Subchronic systemic toxicity The tests conducted were based on ISO 10993-6: Biological evaluation of medical devices - part 6: Tests for local effects after implantation (2007) and ISO 10993-11: Biological evaluation of medical devices - part 11: Tests for systemic toxicity (2006) and update (2016). The subchronic systemic toxicity test evaluates the presence of health risks and / or side effects that may be caused by repeated and / or continuous exposure to a substance. The implantation assay evaluates the local effects after the test substance has been in direct contact with the tissue to which it has been exposed. These assays provide information on the potential for toxic effects on the whole body and target organs, characterize the history and progression of tissue reactions, and form the basis for estimating the biological safety of the test substance. In this sense, this test aimed to evaluate the local and systemic effects of the device product of the present invention applied to bone tissue for 90 days (in accordance with the intended indications and purposes of the product). The test used rabbits (Oryctolagus cuniculus - New Zealand) and inserted the device into the tibia under a specific protocol. After treatment, the body weight of the animals was measured, and clinical signs of toxicity were evaluated weekly at baseline and during the test period. Clinical signs of toxicity include, but are not limited to, convulsions, mutations, weakness, ataxia, tremors, local inflammation, dyspnea, lacrimation, salivation, diarrhea, pore formation, and cachexia. After 90 days, blood samples were collected from the animals, and necropsy and organ collection were performed. The organs here include the liver, spleen, left kidney, left adrenal gland, testis / ovary, proximal (popliteal) and distal (mesenteric) lymph nodes, and the implantation site. As a result of the analysis, it was shown that there were no local and systemic toxic effects in the rabbits, and it was sufficient to demonstrate its safety, effectiveness, and potential performance for the intended use. Also, the results presented are sufficient to justify the need not to conduct the following tests.That is, blood compatibility test (ISO10993-4) and immunotoxicity test (ISO10993-20) (when there are no blood and immunological changes), chronic toxicity test (ISO10993-11) (when there are no systemic changes indicating the need for long-term follow-up), reproductive toxicity test (ISO10993-3) (when there are no histopathological changes in the reproductive organs), and toxicokinetics test (ISO10993-16) (when there is no potential toxicity shown by the device of the present invention).

[0064] 11. Tests in animal models - Conducted for 180 days The bone implant test is to evaluate the local effects of the material after implantation in an animal species, aiming to characterize the history and evolution of the tissue reaction after implanting a medical device and to evaluate its biological safety. A round cut with a diameter of 3 mm was made at a site near the tubercle of the tibia of a rabbit (Oryctolagus cuniculus - New Zealand), and both the device (test) of the present invention and the reference product (control) were inserted. The bone tissue of the animal showed a local extensive area composed of a moderate layer of new bone tissue at the test site. In this area, there were many bone cells, the rhythm of osteoblasts was moderate to moderate, and the fiber orientation was indefinite. In addition, a slightly to moderately amount of non-mineralized bone matrix was separated from the lamellar area with a Haversian system by a cementing line, and a slight to moderate change in tissue structure was observed. The local capillary proliferation (1 - 3 buds) associated with bone formation was very slight. In the semi-quantitative evaluation of the local bone reaction, the average value of the test site was 13.6, the average value of the control site was 14.6, and the tissue reaction index was -1.0 (non-reactive compared to the control). During the experimental period, no significant changes were observed in the animals, and no significant macroscopic changes were observed during autopsy, indicating that there was no toxicity in the presented parameters.

[0065] 12. Tests in sheep 12.1 Test overview This study aimed to analyze the safety and efficacy of the test article of the present invention in sheep for cartilage repair ability and its effect on joint inflammatory response. As the method of this study, the transplantation sites after treatment of cartilage lesions in female adult sheep (Ovis aries) were evaluated by histopathological analysis comparing with the control (control) or reference treatment.

[0066] Cartilage lesions with a diameter of 10 mm were induced directly and at the center of support of the medial condyle of the left femur until the subchondral bone of 16 sheep without signs of osteoarticular or systemic changes was exposed. After induction of the lesions, each animal received a transplantation site at the lesion site of the left pelvic limb and received control treatment (at the lesion site of the right pelvic limb) (8 animals for each treatment). The control treatment was infiltration with 0.9% NaCl saline (control), or infiltration with 0.9% NaCl saline (microfracture) after 5 microfractures to the subchondral bone. Treatment with the test article and the reference article consisted of fixing the membrane of the present invention (test article) and ChondroGide® (reference article) to the microfracture using a fibrin adhesive. The animals were exposed to this treatment for 26 weeks. After the end of the period, all animals were anesthetized and euthanized and examined macroscopically. Tissue samples and specimens of the implant site were processed and sent for imaging and macroscopic analysis.

[0067] 12.2 Analytical methods 1. Macroscopic evaluation The distal segment of the femur composed of both condyles and the greater trochanter, without adjacent soft tissue, was photographed and videoed. Among these, 1 video and 3 photos were sent for macroscopic evaluation in a "blind test" by a total of 3 evaluators, 1 veterinarian and 2 physicians with rich experience in orthopedic surgery.

[0068] The macroscopic (naked eye) evaluation of the articular cartilage of the medial condyle of the femur was performed according to the guidelines proposed by the International Society of Cartilage Research (ICRS) and classified as normal, nearly normal, abnormal, and severely abnormal (Table 1). Table. Evaluation of cartilage repair by ICRS

[0069]

Table 3

[0070] The agreement among evaluators regarding the overall evaluation of repair was analyzed using Fleiss' kappa coefficient κ(2). This is because this scale is used to determine the level of agreement among two or more evaluators when the evaluation method is measured on a categorical scale.

[0071] To compare groups regarding the global evaluation of repair, an ordinal logistic regression model with random effects was proposed. This model enables the association between independent variables and an ordinal categorical response variable with levels greater than 2. Also, this model takes into account the existence of scales greater than 1 for each sample unit because the same sheep may be analyzed at knees D and E. Also, this model is adjusted by left / right and evaluator.

[0072] In all analyses, a significance level of 5% was adopted.

[0073] 12.3 Bone density measurement After dissection through a device manufactured by Shimadzu Corporation (model SCT - 7800 CT, standardized at 0.5 mm slice, mA 100, and KVP 120) to remove adjacent soft tissues, computer tomography images were obtained from the distal segment of the femur. CT images were obtained from 32 knees included in this study. For evaluation, the images were visualized in cross - section by Synapse PD - S Viewer software (Fuji Film - Tokyo, Japan). Subchondral sclerosis was determined by bone density measurement analysis using ImageJ software. For this purpose, three images were acquired for each knee evaluated in this study (a total of 96 images), the condyle was selected and classified into pixels. The lateral condyle (negative control) was also evaluated in all images, and a baseline value of 119,198 pixels was obtained from its average value.

[0074] To compare between groups and over time for bone density measurement variables, a linear regression model with mixed effects (random and fixed effects) adjusted for left and right was proposed. Linear mixed effects models are used in data analysis where the responses are grouped (multiple measurements on the same individual) and the assumption of independence between observations within the same group is not appropriate (3). These models assume that the residuals have a normal distribution with mean 0 and constant variance σ², and have been verified by appropriate graphs such as histograms, quantile - quantile, and variance. For comparison, orthogonal contrast post - hoc tests were used.

[0075] 12.4 Results 1. Overall macroscopic evaluation The results of the overall macroscopic evaluation are shown in the table below. Table: Results obtained from the overall macroscopic evaluation

[0076]

Table 4

[0077] The results of analyzing the agreement among evaluators are shown in the table below. As a result, the agreement among evaluators was good. Table. Analysis of evaluator agreement in overall macroscopic evaluation

[0078]

Table 5

[0079] The results of comparison between different treatments are shown in the table below. There was no significant difference between the macroscopic evaluations of the microfracture treatment and the control treatment, or between these treatments and the comparison items. There was no statistical difference between the test product and the comparison product, but unlike the comparison items, the test item showed a significant difference when compared with the control and microfracture treatments. Table Comparison of overall macroscopic evaluation data

[0080]

Table 6

[0081] 2. Bone density measurement The results of the median of subchondral sclerosis obtained in the evaluation of bone density measurement are shown in the following table. Table Median of subchondral sclerosis obtained in the evaluation of bone density measurement

[0082] [Table 7]

[0083] The results of the comparative analysis of bone density measurement data are shown in the following table. There were differences between the negative control and all treatments. The test article had a lower median of subchondral sclerosis than microfracture and control treatment, but showed no statistical difference in relation to the comparator article. The comparator article showed lower medians for control treatment and microfracture treatment, but the differences were not significant. There was no statistical difference between microfracture treatment and control treatment.

[0084] The test results indicate that the coverage of osteochondral lesions by the test article can reduce the inflammatory process and bone deposition in subchondral bone (4), showing results similar to those of the comparator article. Table Comparison of bone density measurement data

[0085] [Table 8]

[0086] Conclusion From the analysis performed, the present invention showed superiority in relation to control treatment and microfracture treatment and was equivalent in relation to treatment with the comparator article.

[0087] Moreover, in the joints of sheep using the present invention, no side effects were observed. The present invention and the collagen scaffold (Chondro-Guide) showed excellent ICRS scores compared to the control group (P≤0.0001 and P≤0.01, respectively). The cartilage repair in the present invention group was better compared to the group with microfracture only (P≤0.01), suggesting that the present invention provides better cell support and promotes the chondrogenic differentiation of local mesenchymal cells. In addition, there were no statistically significant differences in the biomarkers of sheep synovial fluid among the groups.

[0088] The results of the test indicate that the present invention is a safe scaffold that provides better cell support, shows potential improvement in chondrogenic differentiation, and can improve the quality of cartilage repair. In addition, the mechanical and physicochemical properties of the present invention enable personalization and fixation by suturing on their hosts.

[0089] Furthermore, the microfracturing technique in sheep promotes cyst formation, while the present invention has a protective effect and can reduce the cyst formation and sclerosis of SCB.

[0090] Manufacturing process of the device according to the present invention The method for preparing the device according to the present invention comprises the following steps. That is, the method a. a step of putting the raw materials into a vacuum oven at room temperature; b. a step of weighing the raw materials and preparing a dissolution solution with an organic solvent; c. a step for an employee to insert a program suitable for the operation and set up the machine; d. a step of putting the polymer dissolution solution into the machine, then operating the machine to produce a membrane at a predetermined flow rate; e. a step of taking out the membrane blanket and putting it into a vacuum oven for removing residual organic solvents; f. a step of sending the blanket to a CO2 laser cutting machine to perform membrane cutting treatment; g. a step of storing the membrane in a sealed container; h. The film is individually packaged under laminar flow in the form of polyethylene terephthalate (PET) blisters (bubbles) for primary packaging, and then the blisters are heat-sealed with Tyvek type surgical-grade paper. One blister of the product is placed in a secondary packaging in the form of a PET / aluminum pouch under laminar flow, and the product is placed in a sterilization package made of surgical-grade paper. The package is thermally sealed and a label indicating sterilization by EtO is attached. This process h is carried out so that the EtO gas effectively penetrates inside the package to sterilize the product.

[0091] Although examples of preferred embodiments of the present invention have been described, the scope of the present invention is limited only by the content of the appended claims (including possible equivalents included therein), and it should be understood that other possible variations of the described inventive concept are included.

Claims

1. A dental / medical device particularly used for inducing tissue reconstruction and / or regeneration of bone defects and other connective tissues (including gums, skin, cartilage, or cornea), The device has an absorbent synthetic film based on poly(dioxanone), The film has a substantially rectangular cross-section, a thickness between 0.05 mm and 2.00 mm, a width between 15 mm and 200 mm, and a length between 20 mm and 200 mm. A device characterized by the following features.

2. In the device according to claim 1, The device includes graphene A device characterized by the following features.

3. In the device according to claim 2, Contains graphene oxide at concentrations ranging from 0.52% to 1.35%. A device characterized by the following features.

4. In the device according to claim 1, stem cells A device characterized by the following features.

5. In the device according to claim 3, The aforementioned stem cells are autologous adult mesenchymal stem cells obtained from a patient's skin punch. A device characterized by the following features.

6. In the device according to claim 1, The aforementioned device is a dental device having a thickness of 0.25 mm to 2.00 mm, a width of 15 mm to 30 mm, and a length of 20 mm to 40 mm, and having a substantially rectangular cross-section. A device characterized by the following features.

7. In the device according to claim 1, The aforementioned device has a substantially rectangular cross-section with a thickness of 0.25 mm to 2.00 mm, a maximum width of 200 mm, and a maximum length of 200 mm, and is intended for medical and orthopedic use. A device characterized by the following features.

8. A method of using the device according to any one of claims 1 to 7, The above-described method of use is used to induce tissue reconstruction and / or tissue regeneration of bone defects or other connective tissue (including gums, skin, cartilage, or cornea). A method of use characterized by the above.

9. A method of use according to claim 8, The above method of use is used in the treatment of intraosseous and soft tissue peri-implant and periodontal disease defects. A method of use characterized by the above.

10. A method for manufacturing a device according to any one of claims 1 to 7, wherein the manufacturing method is: a. A process of placing raw materials in a vacuum greenhouse at room temperature, b. A step of weighing the raw materials and preparing a solution with an organic solvent, c. The process by which an employee inserts a program suitable for operation and sets up the machine, d. A step of introducing a polymer dissolution solution into the machine, operating the machine, and manufacturing a film at a predetermined flow rate, e. The process involves removing the membrane blanket and placing it in a vacuum greenhouse for removing residual organic solvents, f. The blanket is CO 2 The process involves sending the material to a laser cutting machine where the film is cut, g. The process of storing the film in a sealed container, h. The process of individually packaging the aforementioned membranes. A manufacturing method characterized by including the following.

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