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1.
Materials (Basel) ; 16(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36770248

RESUMO

Fluoride is one of the elements commonly present in the human environment. Due to its characteristics, it is very widely used in medicine, dentistry, industry or agriculture. On the other hand, its universality possesses a real threat to the human body in the form of acute and chronic poisoning. The aim of this paper is to characterize the properties of fluoride and its effects on the human body, as well as the sources of its occurrence. Particular emphasis is placed on the safety of its use and optimal dosage intake, which prevents accumulation and reduces its potential side effects. The positive effect of proper fluoride supply is widely described. In order to avoid overdose, it is best to consult a specialist to properly select the dosage.

2.
Materials (Basel) ; 15(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35955150

RESUMO

Laparoscopic surgery is undergoing rapid development. Replacing the traditional method of joining cut tissues with sutures or staples could greatly simplify and speed up laparoscopic procedures. This alternative could undoubtedly be adhesives. For decades, scientists have been working on a material to bond tissues together to create the best possible conditions for tissue regeneration. The results of research on tissue adhesives achieved over the past years show comparable treatment effects to traditional methods. Tissue adhesives are a good alternative to surgical sutures in wound closure. This article is a review of the most important groups of tissue adhesives including their properties and possible applications. Recent reports on the development of biological adhesives are also discussed.

3.
Biology (Basel) ; 11(5)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35625363

RESUMO

The literature lacks conclusive evidence that lymphatic vessels can form in the dental pulp. Lymphangiogenesis is believed to occur in an inflamed pulp. If one defines lymphangiogenesis as the development of lymphatic vessels from already existing ones, such a mechanism is possible only when lymphatic vessels are present in healthy teeth. This paper aims to identify lymphatic vessels in the dental pulp using microscopic and immunohistochemical methods under physiological and pathological conditions. The tissue material consisted of human teeth intended for extraction. Our studies and results suggest a moderate correlation between pulp inflammation and the formation of new vessels, including lymphatic vessels.

4.
Materials (Basel) ; 15(7)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35408005

RESUMO

A knitted implant, unilaterally modified with plasma-assisted chemical-vapor deposition (PACVD), and with a nano-layer of fluorine derivative supplementation, for reducing the risk of complications related to adhesions, and the formation of a thick postoperative scar was prepared. The biological evaluation of designed or modified medical devices is the main aspect of preclinical research. If such studies use a medical device with prolonged contact with connective tissue (more than 30 days), biocompatibility studies require a safety assessment in terms of toxicity in vitro and in vivo, allergenicity, irritation, and cancerogenicity, reproductive and developmental toxicity. The ultimate aspect of biological evaluation is biofunctionality, and evaluation of the local tissue response after implantation, resulting in the determination of all aspects of local biocompatibility with the implemented synthetic material. The implantation of PACVD-modified materials in muscle allows us to estimate the local irritation effect on the connective tissue, determining the risk of scar formation, whereas implantation of the above-mentioned knitted fabric into the abdominal wall, assists with evaluating the risk of fistula formation-the main post-surgical complications. The research aimed to evaluate the local reaction of the soft tissues after the implantation of the knitted implants modified with PACVD of the fluoropolymer in the nanostuctural form. The local effect that occurred during the implantation of the designed implants was quantitatively and qualitatively evaluated when PACVD unmodified (reference), and modified medical devices were implanted in the abdominal cavity (intra-abdominal position) for 12 or into the muscles for 56 weeks. The comparative semi-quantitative histological assessment included the severity of inflammatory cells (multinucleated cells, lymphocytes, plasma cells, macrophages, giant cells) and the tissue response (necrosis, neovascularization, fibrosis, and fat infiltration) on a five-point scale. The knitted implants modified by PACVD did not indicate cumulative tissue response when they were implanted in the muscle and intra-abdominally with direct contact with the viscera. They reduced local tissue reaction (score -2.71 after 56 weeks of the implantation) and internal organ adhesion (irritation score -2.01 and adhesion susceptibility -0.3 after 12 weeks of the implantation) compared with the reference (unmodified by PACVD) knitted implant, which had an identical structure and was made of the same source.

5.
Healthcare (Basel) ; 10(2)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35206840

RESUMO

BACKGROUND: From one year to another, dentists have access to more procedures using modern techniques. Many of them can improve the effectiveness of dental procedures and frequently facilitate and accelerate them. OBJECTIVES: Technically advanced devices are an important part of modern dentistry. Over the years, there were developed technologies like ultrasounds, lasers, air abrasion, ozonotherapy, caries diagnostic methods, chemomechanical caries removal (CMCR), pulp vitality tests, computer-controlled local anesthetic delivery (CCLAD). The aim of this study was to investigate the requirement of Polish dentists for such technologies. METHODS: An anonymous questionnaire was posted on a social media group of dentists from Poland. 187 responses were obtained. RESULTS: It turned out that almost every respondent uses ultrasounds, but other technologies are not as popular. 43% use CCLAD, 33% use diagnostic methods, 28% use air abrasion, 25% use dental lasers, 21% use CMCR, 18% use pulp vitality tests and 6% use ozonotherapy. The most common reason for not using the aforementioned technologies were their high cost and the sufficient effectiveness of raditional methods. There was a correlation between use of a dental laser and CCLAD and size of office, CMCR use and dentists' work time and air abrasion use and gender. Many dentists claim that they will try one of the modern technologies in the future. CONCLUSIONS: It can be concluded that Polish dentists tend to use ultrasounds and CCLAD more than any other technology. In the future this may change, so more studies in this topic are needed.

6.
Biology (Basel) ; 10(12)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34943171

RESUMO

Despite many studies, opinions on the lymphatic system of the teeth are still incompatible. Studies using light and electron microscopy and directly using methods such as a radioisotope (radionuclide) scan and interstitial fluid pressure measurement reported incomplete results. Immunohistochemistry (IHC) plays the main role in investigating presence of the lymphatic system in dental tissues. This method uses labeled antibodies against antigens typical of lymphatic vessels. The use of appropriate staining enables the detection of antigen-antibody reaction products using a light (optical), electron or fluorescence microscope. However, these studies do not show the system of vessels, their histologic structure under physiological conditions and inflammation as well as the lymphangiogenesis process in the dental pulp. Unfortunately, there is a lack of studies associating the presence of lymphatic vessels in the dental pulp with local lymphatic nodes or large vessels outside the tooth. In the scientific and research environment, the evaluation of the lymphatic system of the teeth is problematic because it is quite difficult to clearly distinguish lymphatic vessels from small blood vessels. Despite many indications of the presence of lymphatic vessels in the pulp chamber, this problem remains open and needs further research.

7.
Materials (Basel) ; 14(18)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34576522

RESUMO

In recent years, nanomaterials have become increasingly present in medicine, especially in dentistry. Their characteristics are proving to be very useful in clinical cases. Due to the intense research in the field of biomaterials and nanotechnology, the efficacy and possibilities of dental procedures have immensely expanded over the years. The nano size of materials allows them to exhibit properties not present in their larger-in-scale counterparts. The medical procedures in endodontics are time-consuming and mostly require several visits to be able to achieve the proper result. In this field of dentistry, there are still major issues about the removal of the mostly bacterial infection from the dental root canals. It has been confirmed that nanoparticles are much more efficient than traditional materials and appear to have superior properties when it comes to surface chemistry and bonding. Their unique antibacterial properties are also promising features in every medical procedure, especially in endodontics. High versatility of use of nanomaterials makes them a powerful tool in dental clinics, in a plethora of endodontic procedures, including pulp regeneration, drug delivery, root repair, disinfection, obturation and canal filling. This study focuses on summing up the current knowledge about the utility of nanomaterials in endodontics, their characteristics, advantages, disadvantages, and provides a number of reasons why research in this field should be continued.

8.
Materials (Basel) ; 14(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34576681

RESUMO

The lungs are a common site of metastases from malignant tumors. Their removal with a minimal but safe tissue margin is essential for the long-term survival of patients. The aim of this study was to evaluate the usefulness of a 1940 nm thulium-doped fiber laser (TDFL) and a 1470 nm diode laser (DL) in a pig model of lung surgery that involved the incision and excision of lung tissue. Histopathological analysis was performed on days 0 and 7 after surgery. Neither TDFL nor DL caused significant perioperative or postoperative bleeding. Histological analysis revealed the presence of carbonized necrotic tissue, mixed fibrin-cellular exudate in the superficial zone of thermal damage and bands of deeper thermal changes. The mean total width of thermal damage on day 0 was 499.46 ± 61.44 and 937.39 ± 109.65 µm for TDFL and DL, respectively. On day 7, cell activation and repair processes were visible. The total width of thermal damage was 2615.74 ± 487.17 µm for TDFL vs. 6500.34 ±1118.02 µm for DL. The superficial zone of thermal damage was narrower for TDFL on both days 0 and 7. The results confirm the effectiveness of both types of laser in cutting and providing hemostasis in the lungs. TDFL caused less thermal damage to the lung parenchyma than DL.

9.
Nanomaterials (Basel) ; 11(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207064

RESUMO

The replacement of affected blood vessels of the polymer material can cause imbalances in the blood haemostatic system. Changes in blood after the implantation of vascular grafts depend not only on the chemical composition but also on the degree of surface wettability. The Dallon® H unsealed hydrophilic knitted vascular prosthesis double velour was assessed at work and compare with hydrophobic vascular prosthesis Dallon®. Spectrophotometric studies were performed in the infrared and differential scanning calorimetry, which confirmed the effectiveness of the process of modifying vascular prostheses. Determination of the parameters of coagulation time of blood after contact in vitro with Dallon® H vascular prosthesis was also carried out. Prolongation of activated thromboplastin time, decreased activity of factor XII, IX and VIII, were observed. The prolonged thrombin and fibrinogen were reduced in the initial period of the experiment. The activity of plasminogen and antithrombin III and protein C were at the level of control value. The observed changes in the values of determined parameters blood coagulation do not exceed the range of referential values for those indexes. The observed changes are the result of considerable blood absorptiveness by the prosthesis of blood vessels and their sealing.

10.
Materials (Basel) ; 14(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923581

RESUMO

BACKGROUND: The aim of this study was to evaluate the usefulness of a thulium-doped fiber laser and a diode laser in zero ischemia kidney surgery, by carrying out a comparative study in a pig model. MATERIAL AND METHODS: Research was carried out on 12 pigs weighing 30 kg each. A thulium-doped fiber laser (TDFL) and a diode laser (DL) operating at wavelengths of 1940 and 1470 nm, respectively, were used. The cut sites were assessed both macroscopically and microscopically. The zone of thermal damage visible in the histopathological preparations was divided into superficial and total areas. RESULTS: During partial nephrectomy, moderate to minimal bleeding was observed, which did not require additional hemostatic measures. All animals survived the procedure. On day 0, the total thermal damage depth was 837.8 µm for the TDFL and 1175.0 µm for the DL. On day 7, the depths were 1556.2 and 2301.7 µm, respectively. On day 14, the overall thermal damage depth for the DL was the greatest (6800 µm). The width of the superficial zone was significantly reduced on days 7 and 14 after TDFL application. CONCLUSION: Both lasers are suitable for partial wedge nephrectomy without ischemia in pigs. The TDFL produced similar or better hemostasis than the DL, with a smaller zone of thermal damage and, therefore, seems more suitable for application in human medicine.

11.
Materials (Basel) ; 14(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33805176

RESUMO

The aim of this review article is to present various material groups, including ceramics, composites and hybrid materials, currently utilized in the field of CAD/CAM. The described technology is amongst the most important in modern prosthetics. Materials that are applicable in this technique are constantly tested, evaluated and improved. Nowadays, research on dental materials is carried out in order to meet the increasing demand on highly aesthetic and functional indirect restorations. Recent studies present the long-term clinical success of restorations made with the help of both ceramic and composite materials in the CAD/CAM method. However, new materials are developed and introduced that do not have long-term in vivo observations. We can outline a monolithic polymer-infiltrated ceramic network and zirconia teeth support that show promising results to date but require further assessment. The materials will be compared with regard to their mechanical and clinical properties, purpose, advantages and limitations.

12.
Nanomaterials (Basel) ; 11(2)2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33669987

RESUMO

Sclerotherapy is the chemical occlusion of vessels using an intravenous injection of a liquid or foamed sclerosing agent that is used in the therapy of blood and lymphatic vessels malformations in the young, and for spider veins, smaller varicose veins, hemorrhoids and hydroceles in adults. This study aimed to assess the effectiveness of mechanosclerotherapy of venous veins with a new device-Flebogrif®-based on an animal model. The experiment was performed on nine Polish Merino sheep weighing 40-50 kilograms. The animals were anesthetized intravenously. The material was divided into three groups: two experimental (1 and 2) and control (3) group. The first experimental group was treated with the use of Flebogrif® and a sclerosant simultaneously, while only Flebogrif® was used in the second experimental group. Flebogrif® was applied into the lateral saphenous vein of both pelvic limbs. The vessel wall thickness was estimated at four points of the histological image in mm (V1, V2, V3, V4). For one month, the animals were euthanized, and the occlusion rate of the treated veins and changes in the vein wall were determined. Histological slides were analyzed under a light microscope and histometry of the vein wall was performed. The Shapiro-Wilk test and the quantity of the investigated parameter groups allowed for using a non-parametric method at four points to compare thickness measurements (the Mann-Whitney test), with p < 0.05. The Mann-Whitney test indicated statistically significant differences between both experimental groups. The results obtained from morphometrical and histological analysis showed better results in the first experimental group than those of the second experimental group. Finally, statistical analysis revealed significant differences between the both the experimental group and control group in morphological analysis. The achieved results allowed us to conclude that the simultaneous use of Flebogrif® and a sclerosant yielded better results of vein lumen reduction than the use of Flebogrif® alone.

13.
Nanomaterials (Basel) ; 11(2)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525572

RESUMO

Nanotechnology has gained importance in recent years due to its ability to enhance material properties, including antimicrobial characteristics. Nanotechnology is applicable in various aspects of orthodontics. This scientific work focuses on the concept of nanotechnology and its applications in the field of orthodontics, including, among others, enhancement of antimicrobial characteristics of orthodontic resins, leading to reduction of enamel demineralization or control of friction force during orthodontic movement. The latter one enables effective orthodontic treatment while using less force. Emphasis is put on antimicrobial and mechanical characteristics of nanomaterials during orthodontic treatment. The manuscript sums up the current knowledge about nanomaterials' influence on orthodontic appliances.

14.
Nanomaterials (Basel) ; 11(2)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498453

RESUMO

This review is an attempt to summarize current research on ozone, titanium dioxide (TiO2), silver (Ag), copper oxide CuO and platinum (Pt) nanoparticles (NPs). These agents can be used in various fields of dentistry such as conservative dentistry, endodontic, prosthetic or dental surgery. Nanotechnology and ozone can facilitate the dentist's work by providing antimicrobial properties to dental materials or ensuring a decontaminated work area. However, the high potential of these agents for use in medicine should be confirmed in further research due to possible side effects, especially in long duration of observation so that the best way to apply them can be obtained.

16.
Adv Clin Exp Med ; 29(11): 1283-1297, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33269814

RESUMO

BACKGROUND: Novel materials used for dentin hypersensitivity (DH) treatment, including hydroxyapatite-based desensitizers, are not only effective in occluding dentinal tubules, but are also biocompatible and non-toxic. A newly formulated desensitizer containing hydroxyapatite was evaluated in comparison to commercially available desensitizers. OBJECTIVES: To compare the occluding efficacy and durability of 3 commercially available desensitizing agents with a pharmaceutical composition developed by the authors based on hydroxyapatite (HAp). MATERIAL AND METHODS: For the experiment, 40 disc-shaped dentin specimens (5 mm thick) were obtained from extracted human teeth. Each disc was divided into 4 sections, so that each desensitizing agent could be applied to each specimen and prepared for further evaluation in most homogenous conditions. The chemical composition of the dentin surfaces was analyzed using scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectroscope (EDS), Fourier-transform infrared (FTIR) and Raman spectra techniques. The specimens were immersed in an artificial saliva solution for 24 h, 48 h and 7 days to assess the durability of the layers and the tubule-obliteration effectiveness. Data analysis was performed using Student's t-test with an average value of normal distribution at an unknown variance with a standard deviation (SD) of σ-0.4. RESULTS: All the test groups showed some degree of dentinal tubule occlusion or a covering layer, but the HAp-based composition proved to be the longest-lasting. It was concluded that the developed pharmaceutical composition creates a coating on the dentin surface built of hydroxyapatite crystals sized 10-20 µm, which are likely to constitute a reservoir of calcium and phosphate ions, as well as smaller crystals (0.2-0.3 µm) that occlude dentinal tubules. CONCLUSIONS: The composition containing biocompatible hydroxyapatite effectively occluded dentinal tubules and therefore exhibits a potential for reducing the pain and discomfort caused by dentin hypersensitivity.


Assuntos
Sensibilidade da Dentina , Dentina , Sensibilidade da Dentina/tratamento farmacológico , Durapatita , Humanos , Microscopia Eletrônica de Varredura , Saliva Artificial , Espectrometria por Raios X
17.
Nanomaterials (Basel) ; 10(10)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050423

RESUMO

The research has been carried out with a focus on the assessment of the antimicrobial efficacy of pure nanohydroxyapatite, Cu2+-doped nanohydroxyapatite, ozonated olive oil-loaded nanohydroxyapatite, and Cu2+-doped nanohydroxyapatite, respectively. Their potential antimicrobial activity was investigated against Streptococcus mutans, Lactobacillus rhamnosus, and Candida albicans. Among all tested materials, the highest efficacy was observed in terms of ozonated olive oil. The studies were performed using an Ultraviolet-Visible spectrophotometry (UV-Vis), electron microscopy, and statistical methods, by determining the value of Colony-Forming Units (CFU/mL) and Minimal Inhibitory Concentration (MIC).

18.
Materials (Basel) ; 13(13)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645864

RESUMO

BACKGROUND: Recently, the defects of the tooth surface in the cervical region are often restored using composite filling materials. It should meet the needs of the patients regarding esthetics and material stability. The aim of the study was to analyze the tooth root surface at the cervical region after the removal of the composite filling material by means of the Erbium-doped Yttrium Aluminium Garnet (Er: YAG) laser or drill using the scanning electron microscopy (SEM) and fluorescence microscopy. MATERIALS AND METHODS: For the purposes of this study, 14 premolar teeth (n = 14) were removed due to orthodontic reasons. The rectangular shape cavities with 3 mm in width and 1.5 mm in height were prepared with a 0.8 mm bur on high-speed contra-angle in the tooth surface just below cemento-enamel junction (CEJ) and filled with the composite material. The composite material was removed with the Er: YAG laser at a power of 3.4 W, energy 170 mJ, frequency 20 Hz, pulse duration 300 µs, tip diameter 0.8 mm, air/fluid cooling 3 mL/s, and time of irradiation: 6 sec, at a distance from teeth of 2 mm (G1 group, n = 7) or a high-speed contra-angle bur (G2 group, n = 7). After the removal of composite material, the surfaces of teeth were examined using the scanning electron microscopy (SEM) and fluorescence microscopy. RESULTS: The Er: YAG irradiation allowed to remove completely the composite material from the tooth cavity. The study confirmed, that the ends of collagen fibers were only partially denatured after the Er: YAG laser application. CONCLUSION: It has been proved that using the Er: YAG laser is an effective and safe method of composite removal for the dentin surface.

19.
Nanomaterials (Basel) ; 10(6)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580409

RESUMO

Regenerative properties are different in every human tissue. Nowadays, with the increasing popularity of dental implants, bone regenerative procedures called augmentations are sometimes crucial in order to perform a successful dental procedure. Tissue engineering allows for controlled growth of alveolar and periodontal tissues, with use of scaffolds, cells, and signalling molecules. By modulating the patient's tissues, it can positively influence poor integration and healing, resulting in repeated implant surgeries. Application of nanomaterials and stem cells in tissue regeneration is a newly developing field, with great potential for maxillofacial bony defects. Nanostructured scaffolds provide a closer structural support with natural bone, while stem cells allow bony tissue regeneration in places when a certain volume of bone is crucial to perform a successful implantation. Several types of selected nanomaterials and stem cells were discussed in this study. Their use has a high impact on the efficacy of the current and future procedures, which are still challenging for medicine. There are many factors that can influence the regenerative process, while its general complexity makes the whole process even harder to control. The aim of this study was to evaluate the effectiveness and advantage of both stem cells and nanomaterials in order to better understand their function in regeneration of bone tissue in oral cavity.

20.
Materials (Basel) ; 13(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32151086

RESUMO

Partial and total splenectomies are associated with a high risk of substantial blood loss. Lasers operating at wavelengths strongly absorbed by water have the potential to improve hemostasis and cut while providing a narrow zone of thermal damage. The aim of this study is to compare a thulium-doped fiber laser (TDFL) emitting a wavelength of 1940 nm and a diode laser (DL) operating at 1470 nm for spleen surgery in a pig model. A partial splenectomy and spleen incisions were made in 12 animals using the two laser devices. The hemostasis was evaluated visually during surgeries. Post-mortem and histopathological evaluations were done on days 0, 7, and 14 following surgery. Neither TDFL nor DL caused bleeding on day 0 or delayed bleeding. On day 14, pale streaks at the site of incision were slightly wider after cutting with DL than with TDFL. Histological analysis revealed a carbonized zone with exudation and a deeper zone of thermal tissue damage on day 0. The width of the thermal changes was 655.26 ± 107.70 µm for TDFL and 1413.37 ± 111.85 µm for DL. On day 7, a proliferation of fibroblasts and splenocytes was visible, as well as a formation of multinucleated giant cells adjacent to the residues of carbonization. The zone of thermal damage was broader for DL (1157.5 ± 262.77 µm) than for TDFL (682.22 ± 116.58 µm). On day 14, cutting sites were filled with connective and granulation tissues with the residues of carbonization. The zone of thermal damage was narrower for TDFL (761.65 ± 34.3 µm) than for DL (1609.82 ± 202.22 µm). Thus, both lasers are efficient in spleen surgery, providing good hemostasis. However, TDFL produces a narrower zone of thermal damage, which suggests its better efficiency for spleen surgery, especially when performing more precise procedures.

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