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The purpose of this study was to evaluate the effects of Nd:YAG laser with flat-top handpiece on the in vitro growth of Candida albicans and Streptococcus mutans. The incidence of C. albicans (opportunistic commensal) and S. mutans (facultatively anaerobic) infections is increasing, despite available treatments. Cultures of Streptococcus mutans and Candida albicans were irradiated using Nd:YAG laser (LightWalker, Fotona) with flat-top handpiece (Genova, LightWalker, Fotona) at the following parameters: group G1: 0.25 W, 10 Hz, 15 s, 3 J and group G2: 1 W, 10 Hz, 60s, 59 J. The results were evaluated directly and 24 h after irradiation using a quantitative culture method (estimation of colony-forming units in 1 ml of suspension, cfu/ml), and microscopic analysis with Janus green stain and compared with control group in which laser was not applied. C. albicans was reduced by 20 up to 54% for G1, and for G2 by 10 up to 60% directly after the application. The cfu/ml values for S. mutans decreased by 13% (p = 0.1771) for G1 and 89% (p < 0.0001) for G2. In both test groups 24 h after the application, the number of colony-forming units decreased by 15-46% for G1 and by 15-64% for G2. The arrested cell division, increasing the surface area and increasing the number of metabolically inactive cells, were observed in morphometric analysis. Macroscopic and microscopic analyses revealed a reduction in cell number and a significant decrease of cell metabolism after laser application for both C. albicans and S. mutans.
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Candida albicans/crescimento & desenvolvimento , Candida albicans/efeitos da radiação , Lasers de Estado Sólido , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/efeitos da radiação , Candida albicans/citologia , Humanos , Viabilidade Microbiana/efeitos da radiação , Streptococcus mutans/citologiaRESUMO
Abstracts: The aim of the study was to evaluate the biocompatibility and bioactivity of two new prototype implants for bone tissue regeneration made from biodegradable fibrous materials. The first is a newly developed poly(l-lactide-co-glycolide), (PLGA), and the second is a blend of PLGA with synthetic poly([R,S]-3-hydroxybutyrate) (PLGA/PHB). The implant prototypes comprise PLGA or PLGA/PHB nonwoven fabrics with designed pore structures to create the best conditions for cell proliferation. The bioactivity of the proposed implants was enhanced by introducing a hydroxyapatite material and a biologically active agent, namely, growth factor IGF1, encapsulated in calcium alginate microspheres. To assess the biocompatibility and bioactivity, allergenic tests and an assessment of the local reaction of bone tissue after implantation were performed. Comparative studies of local tissue response after implantation into trochanters for a period of 12 months were performed on New Zealand rabbits. Based on the results of the in vivo evaluation of the allergenic effects and the local tissue reaction 12 months after implantation, it was concluded that the two implant prototypes, PLGA + IGF1 and PLGA/PHB + IGF1, were characterized by high biocompatibility with the soft and bone tissues of the tested animals.
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Materiais Biocompatíveis/administração & dosagem , Regeneração Óssea/efeitos dos fármacos , Ácido Láctico/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Feminino , Cobaias , Ácido Láctico/efeitos adversos , Masculino , Nanocompostos/química , Ácido Poliglicólico/efeitos adversos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Alicerces Teciduais , CicatrizaçãoRESUMO
In response to the demand for new implant materials characterized by high biocompatibility and bioresorption, two prototypes of fibrous nanocomposite implants for osseous tissue regeneration made of a newly developed blend of poly(l-lactide-co-glycolide) (PLGA) and syntheticpoly([R,S]-3-hydroxybutyrate), PLGA/PHB, have been developed and fabricated. Afibre-forming copolymer of glycolide and l-lactide (PLGA) was obtained by a unique method of synthesis carried out in blocksusing Zr(AcAc)4 as an initiator. The prototypes of the implants are composed of three layers of PLGA or PLGA/PHB, nonwoven fabrics with a pore structure designed to provide the best conditions for the cell proliferation. The bioactivity of the proposed implants has been imparted by introducing a hydroxyapatite material and IGF1, a growth factor. The developed prototypes of implants have been subjected to a set of in vitro and in vivobiocompatibility tests: in vitro cytotoxic effect, in vitro genotoxicity and systemic toxicity. Rabbitsshowed no signs of negative reactionafter implantation of the experimental implant prototypes.
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Implantes Absorvíveis , Regeneração Óssea , Hidroxibutiratos , Ácido Láctico/química , Ácido Láctico/farmacologia , Nanocompostos , Poliésteres , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacologia , Alicerces Teciduais , Animais , Biomarcadores , Linhagem Celular , Sobrevivência Celular , Humanos , Hidroxibutiratos/química , Ácido Láctico/toxicidade , Camundongos , Nanocompostos/química , Poliésteres/química , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , Proibitinas , Coelhos , Engenharia TecidualRESUMO
BACKGROUND: The development of technologies and scientific disciplines connected with medical implantation devices is dynamically affecting modern treatments by contemporary medicine and veterinary medicine; it also entails a need to monitor their impact on living organisms. OBJECTIVES: The aim of the study was to conduct a comparative histological evaluation of the response of soft tissues after implanting monofilament fibers from resorbable glyconate and from non-resorbable polypropylene (PP) and polyamide (PA) in rats. MATERIAL AND METHODS: Non-resorbable polyamide-based fibers were applied to skin anastomoses in rats. Macroscopic and histological evaluations were performed on the 7th, 14th and 30th days. Non-resorbable polypropylene fibers and resorbable glyconate fibers (composed of 72% glycolide, 14% trimethylene carbonate and 4% caprolactone) were implanted in muscle tissue for periods of 7, 14, 30 and 90 days. RESULTS: A semi-quantitative and qualitative histological evaluation found different dynamics and degrees of intensification of cell and tissue response around the resorbable and non-resorbable fibers being tested. The resorption process of the glyconate threads caused a prolonged inflammatory cellular response compared to the non-resorbable threads; it passed, however, without the participation of giant cells. Around the non-resorbable threads the observed cellular response was less intensified, with the formation of single polymorphonuclear macrophages around the PP threads, along with a stronger degree of fibrosis and the presence of fatty infiltrate. CONCLUSIONS: During the early period, moderately intensified inflammatory cell response with the presence of single giant cells was observed around the non-degradable PA and PP fibers. In the late period, a band of fibrous connective tissue was present around the PP threads. Glyconate fibers underwent fragmentation and the process of resorption, which was associated with a weakly intensified inflammatory process lasting up to 90 days after implantation.
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Implantes Absorvíveis/efeitos adversos , Inflamação/induzido quimicamente , Animais , Dioxanos , Músculos/patologia , Nylons , Ácido Poliglicólico , Polipropilenos , Ratos , Ratos Wistar , Pele/patologiaRESUMO
Conservative treatment which restores the function, aesthetics and protects remaining tooth structure, and what is the most important, the viability of the tooth pulp, is still needed. Dental fillings replace specialized tissues of the tooth that have been lost due to caries or injury. Any decision concerning the use of a particular restorative material should be individualized and based on the competence regarding the composition, properties and characteristics of the specific restorative material. This requires continuous updating of knowledge about available dental materials as well as education of patients who, according to actual models of dental care, should be active partners in the therapeutic process. The selection of restorative materials is often related to financial abilities of the patients, and more generally to the economic model of organized health care in a particular country. Nowadays, amalgam is increasingly dislodged by adhesive materials which permit to save more tooth structure and allow to preserve natural teeth for a longer time. In the nearest future we can expect further development of minimally invasive techniques and improvements of restorative materials, especially their mechanical properties like strength and wear resistance as well as biocompatibility. The article presents restorative materials used in modern dentistry.
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Materiais Dentários/química , Reparação de Restauração Dentária/instrumentação , Reparação de Restauração Dentária/métodos , Reparação de Restauração Dentária/tendências , PrevisõesRESUMO
BACKGROUNDS: The titanium-aluminum-vanadium alloy (Ti-6Al-4V) is frequently used in implantology due to its biocompatibility. The use of 3D printing enables the mechanical modification of implant structures and the adaptation of their shape to the specific needs of individual patients. METHODS: The titanium alloy plates were designed using the 3D CAD method and printed using a 3D SLM printer. Qualitative tests were performed on the material surface using a microcomputed tomography scanner. The cytotoxicity of the modular titanium plates was investigated using the MTT assay on the L929 cell line and in direct contact with Balb/3T3 cells. Cell adhesion to the material surface was evaluated with hFOB1.19 human osteoblasts. Microbial biofilm formation was investigated on strains of Lactobacillus rhamnosus, Staphylococcus epidermidis, Streptococcus mutans and Candida albicans using the TTC test and scanning electron microscopy (SEM). RESULTS: The surface analysis showed the hydrophobic nature of the implant. The study showed that the titanium plates had no cytotoxic properties. In addition, the material surface showed favorable properties for osteoblast adhesion. Among the microorganisms tested, the strains of S. mutans and S. epidermidis showed the highest adhesion capacity to the plate surface, while the fungus C. albicans showed the lowest adhesion capacity. CONCLUSIONS: The manufactured modular plates have properties that are advantageous for the implantation and reduction in selected forms of microbial biofilm. Three-dimensional-printed modular titanium plates were investigated in this study and revealed the potential clinical application of this type of materials, regarding lack of cytotoxicity, high adhesion properties for osteoblasts and reduction in biofilm formation. The 3D CAD method allows us to personalise the shape of implants for individual patients.
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BACKGROUND: Bioresorbable porous substrates from copolymers have their application in tissue engineering to culture tissues in vitro. The advantage of polymers is the production of thermoplastic elements and their ability to biodegrade in a living body. Gelatin, collagen, alginates are part of dressings used for topical administration of the drug. Research was undertaken to achieve a porous gelatin-alginate matrix which could be used in therapy as among others, a carrier for a drug. OBJECTIVES: Evaluation of the impact of modified gelatin-alginate matrix on activation of plasma coagulation in vivo. MATERIAL AND METHODS: Gelatin-alginate matrix cross-linked with calcium ions was implanted in the muscle tissue of a rat. The control group constituted animals not implanted with material, but they passed the operating procedure. Blood samples of plasma coagulation test and control group were collected after 1, 2, 3, 5, 7, 10, 14 days of the procedure. RESULTS: Prolongation of APTT and shortening of PT and TT with the unchanged values of fibrinogen and the count of platelet cells was observed till the 5th day on the basis of the obtained results. Prolongation of APTT with the unchanged values of the remaining parameters of the coagulation system was observed after 7, 10 and 14 days with unchanged values of PT and TT coagulation. CONCLUSIONS: The matrix gelatin-alginate with calcium ions in the biological environment undergoes biodegradation in soft tissues. This process in the initial period influences the activation of the coagulation within the intrinsic and extrinsic system. From the 5th to 14th day the activation of coagulation was observed only in the intrinsic system.
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Implantes Absorvíveis , Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Compostos de Cálcio/farmacologia , Portadores de Fármacos/farmacologia , Esponja de Gelatina Absorvível/farmacologia , Lactatos/farmacologia , Animais , Reagentes de Ligações Cruzadas , Masculino , Músculo Esquelético/cirurgia , Ratos , Ratos WistarRESUMO
BACKGROUND: Preventing blood clots formation on the biomaterials surface and finding the causes of their appearance are the leading research subjects while working out biomaterials for grafts into the circulation system. Interaction between the biological environment and the carbon implant is closely connected with the properties of its surface. Implants whith surfaces covered with pyrolytic carbon is characterised by athrombogenity have particular significance in medical applications. OBJECTIVES: Assessment of the influence of a pyrolytic carbon surface on the activation of coagulation system. MATERIAL AND METHODS: Full human blood was subjected to temporal contact in vitro with the surface of low-temperature isotropic carbon (LTI). The haemostatic action of pyrolytic carbon was determined through marking the chosen parameters of the coagulation system and the recalcification time on the material surface. The evaluation of the topography of the material was performed in the scanning microscopy. RESULTS: Changes in the values APTT, PT, TT, fibrinogen and activity of factors F XII, F IX, F VIII as well as AT III, protein C and plasminogen were not observed in the studies of the plasmatic coagulation system. The blood coagulation time on the material surface was elongated in comparison with the surface of glass and polystyrene surface. CONCLUSIONS: Direct contact of blood with the surface of carbon LTI elongates clot formation, while not changing the parameters of the plasmatic coagulation system in temporal contact.
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Materiais Biocompatíveis/farmacologia , Células Sanguíneas/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Carbono/farmacologia , Hemostáticos/farmacologia , Células Sanguíneas/citologia , Humanos , Técnicas In Vitro , Propriedades de SuperfícieRESUMO
BACKGROUND: Knowledge of the relation of biomaterials and living tissues constitutes necessary information which should be used when composing a set of optimal carriers, e.g. for drugs or preparations supporting blood clotting. OBJECTIVES: This paper presents an assessment of the influence of contact of gelatin-alginian matrixes with blood on leukocyte reactivity: the ability of mononuclear cells (lymphocytes and monocytes) to create a radial segmentation of nuclei--RS (the morphological change), and the ability of leukocytes to phagocytosis of yeast Saccharomyces cerevisiae cells and to produce active oxygen derivatives (functional changes). MATERIAL AND METHODS: After having contact with the matrixes, the test of induced and spontaneous RS, the phagocytic test and nitroblue tetrazolium reduction test for blood leukocytes were performed. RESULTS: The obtained results showed a decrease in the ability of mononuclear cells to form RS and in the ability of granulocytes to reduce nitroblue tetrazolium--NBT, but an increase in their phagocytic activity. CONCLUSIONS: Temporary contact of gelatin-alginian matrixes with blood did not cause any morphological changes in the leukocytes. However, changes of their reactivity were observed.
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Materiais Biocompatíveis/farmacologia , Portadores de Fármacos/farmacologia , Esponja de Gelatina Absorvível/farmacologia , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Teste de Materiais , Animais , Técnicas In Vitro , Leucócitos/citologia , Fagocitose/efeitos dos fármacos , SuínosRESUMO
The currently popular 3D printing makes it possible to produce spatial scaffolds, the main purpose of which is to obtain implants that have favourable mechanical properties to promote cell adhesion. This study aims to prove the influence of changes in selected geometrical parameters of scaffolds, used in intervertebral cages, on the mechanical properties obtained and thus on the osteointegration of the studied constructs with osteoblasts and fibroblasts. The stiffness values and maximum failure force of four modifications to geometric dimensions of the meshes were determined from the intendation test. Adhesion assays were conducted (including gentle pendulum motion) for Balb/3T3 fibroblasts and NHOst osteoblasts. The study revealed that an important geometrical parameter affecting the strength of the mesh is the height (h) of the connection point between arms of successive mesh cells. There was no significant effect of the mesh geometry on the abundance and survival of Balb/3T3 and NHOst cells. At the same time, fibroblasts were more likely to form colonies in the area where there is fusion of mesh cells, as opposed to osteoblasts that were more numerous at vertices of the mesh.
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Fusão Vertebral , Telas Cirúrgicas , Próteses e Implantes , Fenômenos Mecânicos , Impressão TridimensionalRESUMO
BACKGROUND: Graphene-based materials have great prospects for application in dentistry and medicine due to their unique properties and biocompatibility with tissues. The literature on the use of graphene oxide in orthodontic treatment was reviewed. METHODS: This systematic review followed the PRISMA protocol and was conducted by searching the following databases: PubMed, Scopus, Web of Science, and Cochrane. The following search criteria were used to review the data on the topic under study: (Graphene oxide) AND (orthodontic) ALL FIELDS. For the Scopus database, results were narrowed to titles, authors, and keywords. A basic search structure was adopted for each database. Initially, a total of 74 articles were found in the considered databases. Twelve articles met the inclusion criteria and were included in the review. RESULTS: Nine studies demonstrated the antibacterial properties of graphene oxide, which can reduce the demineralization of enamel during orthodontic treatment. Seven studies showed that it is biocompatible with oral tissues. Three studies presented that graphene oxide can reduce friction in the arch-bracket system. Two studies showed that it can improve the mechanical properties of orthodontic adhesives by reducing ARI (Adhesive Remnant Index). Three studies demonstrated that the use of graphene oxide in the appropriate concentration can also increase the SBS (shear bond strength) parameter. One research study showed that it can increase corrosion resistance. One research study suggested that it can be used to accelerate orthodontic tooth movement. CONCLUSION: The studies included in the systematic review showed that graphene oxide has numerous applications in orthodontic treatment due to its properties.
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The scope of this paper is to compare different dental sealants and flow materials indicated for sealing pits and fissures considering their chemical formula. The narrative review aims to address the following questions: What is the essence of different dental sealants' activity, how does their chemical formula affect their mechanisms of caries prevention, and what makes a dental sealant efficient mean of caries prevention? Another vital issue is whether the sealants that contain fluoride, or any other additions, have potentially increased antimicrobial properties. An electronic search of the PubMed, Cochrane, Web of Science, and Scopus databases was performed. The following keywords were used: (dental sealants) AND (chemical composition). Additionally, information about composition and indications for clinical use provided by manufacturers were utilized. All of the considered materials are indicated for use both in permanent and primary dentition for sealing fissures, pits, and foramina caeca. The selection of suitable material should be made individually and adjusted to conditions of the sealing procedure and patient's needs. Cariostatic mechanisms increasing sealants' effectiveness such as fluoride release are desired in modern dentistry appreciating preventive approach. The review aims are to find crucial elements of sealants' composition which affect their cariostatic mechanisms.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.