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1.
Chemphyschem ; 25(4): e202300758, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38116981

ABSTRACT

The design of novel polymeric carrier systems with functional coatings is of great interest for delivering various bioactive molecules. Microcapsules coated with polyelectrolyte (PE) films provide additional functionality and fine-tuning advantages essential for controlled drug release. We developed hydrogel microcarriers coated with functional PE films with encapsulated substances of natural origin, resveratrol (RES), curcumin (CUR), and epigallocatechin gallate (EGCG), which have cytotoxic and chemopreventive properties. Alginate (ALG) based microparticles were loaded with phytopharmaceuticals using the emulsification method, and then their surface was modified with PE coatings, such as chitosan (CHIT) or poly(allylamine hydrochloride) (PAH). The morphology and mean diameter of microcarriers were characterised by scanning electron microscopy, encapsulation efficiency was determined by UV-Vis spectroscopy, whereas the physicochemical properties of functional PE layers were studied using quartz crystal microbalance with dissipation monitoring and streaming potential measurements. The release profiles of active compounds from the hydrogel microparticles were described using the Peppas-Sahlin model. The cytotoxic effect of designed delivery systems was studied by evaluating their impact on the proliferation, mitochondrial metabolic function, and lipid peroxidation level of 5637 human bladder cancer cells. The present work demonstrates that the physicochemical and biological features of fabricated microcarriers can be controlled by the type of encapsulated anti-cancer agent and PE coating.


Subject(s)
Alginates , Antineoplastic Agents , Humans , Polyelectrolytes/chemistry , Alginates/chemistry , Hydrogels , Polymers , Resveratrol
2.
Clin Oral Investig ; 26(4): 3605-3612, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34882257

ABSTRACT

OBJECTIVES: This exploratory research aimed to evaluate the levels of tryptophan hydroxylase 1 (TPH1) and aromatic l-amino acid decarboxylase (DDC), which play an important role in the serotonin synthesis pathway, in individuals with sleep bruxism (SB) diagnosed using audio-video polysomnography (vPSG) and compare them with that of individuals not presenting with SB. MATERIALS AND METHODS: The study included adult patients hospitalized in the Department and Clinic of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology at the Wroclaw Medical University. The participants underwent a single-night vPSG for the evaluation of the SB parameters. Peripheral blood samples were also collected from them for estimating the serum levels of TPH1 and DDC. RESULTS: A total of 105 patients (80 women and 25 men) were included in the study. All the patients were Caucasians and aged 18-63 years (mean age: 33.43 ± 10.8 years). Seventy-five patients (71.43%) presented with SB, of which 50 (47.62%) had severe SB, while the remaining 30 patients (28.57%) did not. No statistically significant differences in TPH1 and DDC levels were observed between the individuals with SB and without SB. A significant negative correlation was found between tonic SB episodes and DDC levels (p = 0.0012). Other correlations between the SB parameters and the levels of the studied enzymes were statistically insignificant (p > 0.05 for all comparisons). CONCLUSIONS: The levels of the enzymes that are crucial for serotonin synthesis (TPH1 and DDC) did not seem to influence SB. CLINICAL RELEVANCE: This study provides important insights for further research on the relationship between the serotonin pathway and SB, which should take into account not only the process of serotonin synthesis but also the effect of serotonin-dependent neurotransmission on SB.


Subject(s)
Serotonin , Sleep Bruxism , Adolescent , Adult , Female , Humans , Male , Middle Aged , Polysomnography , Young Adult
3.
J Oral Rehabil ; 49(4): 422-429, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34907576

ABSTRACT

BACKGROUND: Sleep bruxism (SB) is a complex behaviour that seems to be associated with the serotoninergic pathway. OBJECTIVES: This exploratory research aimed to evaluate the levels of serotonin in individuals with sleep bruxism diagnosed by video polysomnography. The study also evaluated whether the levels of serotonin were associated with body mass index, heart rate, and sleep parameters. METHODS: The study participants were adults hospitalised in the Department and Clinic of Internal Medicine, Occupational Diseases, Hypertension and Clinical Oncology at the Wroclaw Medical University. They underwent a single-night video polysomnography during which sleep and SB parameters and heart rate were evaluated. Additionally, body mass index and blood serotonin levels were evaluated for each patient. RESULTS: A total of 105 patients were included in this study (80 women and 25 men). All the patients were Caucasians aged 18-63 years, with a mean age ± (standard deviation) of 33.43± 10.8 years. Seventy-five patients (71.43%) presented sleep bruxism (bruxism episodes index ≥2) and 30 (28.57%) did not. Fifty patients (47.62%) presented severe sleep bruxism (bruxism episodes index >4). The results showed that lower blood serotonin levels were associated with severe sleep bruxism; increased bruxism episodes index, rapid eye movement sleep, and body mass index; and decreased maximal pulse. CONCLUSION: Severe sleep bruxism and the associated phenomena seem to co-occur with lower blood serotonin levels. The study supports the hypothesis on the relationship between the serotoninergic pathway and sleep bruxism.


Subject(s)
Serotonin , Sleep Bruxism , Adolescent , Adult , Body Mass Index , Female , Heart Rate , Humans , Male , Middle Aged , Sleep , Young Adult
4.
Int J Mol Sci ; 23(18)2022 Sep 17.
Article in English | MEDLINE | ID: mdl-36142778

ABSTRACT

There is an ongoing search for novel disinfection techniques that are not only effective, cheap, and convenient, but that also do not have adverse effects on the properties of dental impressions. We compared the effects of various methods (UVC, gaseous ozone, commercial solution, and spray) on the dimensional change, tensile strength, and hardness of silicone impressions. Moreover, as a secondary aim, we performed a statistical comparison of the properties of nondisinfected addition (Panasil Putty Soft, Panasil monophase Medium, Panasil initial contact Light) and condensation silicones (Zetaplus Putty and Oranwash L), as well as a comparison of materials of various viscosities (putty, medium-bodied, and light-bodied). Our results revealed that addition silicones had higher dimensional stability, tensile strength, and Shore A hardness compared to condensation silicones. Both traditional (immersion and spraying) and alternative methods of disinfection (UVC and ozone) had no significant impact on the tensile properties and dimensional stability of the studied silicones; however, they significantly affected the hardness, particularly of Oranwash L. Our study demonstrated that, similarly to standard liquid disinfectants, both UVC and ozone do not strongly affect the material properties of most silicones. However, before recommendation, their usefulness for each individual material should be thoroughly evaluated.


Subject(s)
Disinfectants , Ozone , Disinfection/methods , Materials Testing , Silicones , Surface Properties , Viscosity
5.
Int J Mol Sci ; 23(2)2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35054931

ABSTRACT

The aim of the study was to evaluate the influence of thermocycling on the shear bond strength of self-adhesive, self-etching resin cements luted to human dentin and computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics. Three modern self-adhesive dental cements (Maxcem Elite, RelyX U200, Panavia SA) were used to lute three CAD/CAM ceramics (IPS Empress CAD, IPS e.max CAD, IPS e.max ZirCAD) onto the dentin. One conventional cement (Panavia V5) served as a control. After preparation, the samples were subjected to thermocycling as a method of artificial aging of dental materials applied to simulate long-term use in oral conditions. Shear bond strength was evaluated according to PN-EN ISO 29022:2013-10 and failure modes were observed under a light microscope. Statistical analysis was performed. The study demonstrated that a combination of ceramics and cements directly impacts the bond strength. The highest bond strength was observed in Panavia V5, lower in Panavia SA and Maxcem Elite and the lowest-in RelyX U200. Adhesive failure between human dentin and cements was the most common failure mode. Moreover, thermocycling highly decreased bond strength of self-adhesive, self-etching cements.


Subject(s)
Ceramics , Computer-Aided Design , Dentin-Bonding Agents/chemistry , Dentin/chemistry , Resin Cements/chemistry , Temperature , Ceramics/chemistry , Chemical Phenomena , Dental Bonding , Humans , Materials Testing , Shear Strength , Surface Properties
6.
Int J Mol Sci ; 22(19)2021 Sep 25.
Article in English | MEDLINE | ID: mdl-34638678

ABSTRACT

The success of modern dental treatment is strongly dependent on the materials used both temporarily and permanently. Among all dental materials, polymers are a very important class with a wide spectrum of applications. This review aims to provide a state-of-the-art overview of the recent advances in the field of natural polymers used to maintain or restore oral health. It focuses on the properties of the most common proteins and polysaccharides of natural origin in terms of meeting the specific biological requirements in the increasingly demanding field of modern dentistry. The use of naturally derived polymers in different dental specialties for preventive and therapeutic purposes has been discussed. The major fields of application cover caries and the management of periodontal diseases, the fabrication of membranes and scaffolds for the regeneration of dental structures, the manufacturing of oral appliances and dentures as well as providing systems for oral drug delivery. This paper also includes a comparative characteristic of natural and synthetic dental polymers. Finally, the current review highlights new perspectives, possible future advancements, as well as challenges that may be encountered by researchers in the field of dental applications of polymers of natural origin.


Subject(s)
Biological Products/pharmacology , Polymers/pharmacology , Animals , Biocompatible Materials/pharmacology , Humans , Oral Health , Periodontal Diseases/drug therapy , Regeneration/drug effects , Tissue Engineering/methods
7.
Molecules ; 26(19)2021 Oct 06.
Article in English | MEDLINE | ID: mdl-34641600

ABSTRACT

This study aimed to characterize the hydrogel micro- and macro-particles designed to deliver curcumin to human colon cancer cells (LoVo). Six series of vehicles based on sodium alginate (micro- and macro-particles, uncoated, coated with chitosan or gelatin) were synthesized. The uncoated microparticles were fabricated using an emulsion-based technique and the uncoated macroparticles with an extrusion technique, with both coupled with ionotropic gelation. The surface morphology of the particles was examined with scanning electron microscopy and the average size was measured. The encapsulation efficiency, moisture content, and swelling index were calculated. The release of curcumin from the particles was studied in an experiment simulating the conditions of the stomach, intestine, and colon. To evaluate the anticancer properties of such targeted drug delivery systems, the cytotoxicity of both curcumin-loaded and unloaded carriers to human colon cancer cells was assessed. The microparticles encapsulated much less of the payload than the macroparticles and released their content in a more prolonged manner. The unloaded carriers were not cytotoxic to LoVo cells, while the curcumin-loaded vehicles impaired their viability-more significantly after incubation with microparticles compared to macroparticles. Gelatin-coated or uncoated microparticles were the most promising carriers but their potential anticancer activity requires further thorough investigation.


Subject(s)
Adenocarcinoma/drug therapy , Colorectal Neoplasms/drug therapy , Curcumin/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacology , Hydrogels/chemistry , Hydrogels/pharmacology , Alginates/chemistry , Alginates/pharmacology , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Chitosan/chemistry , Chitosan/pharmacology , Drug Delivery Systems/methods , Gelatin/chemistry , Gelatin/pharmacology , Humans , Microspheres , Particle Size
8.
Molecules ; 26(5)2021 Feb 25.
Article in English | MEDLINE | ID: mdl-33668944

ABSTRACT

For long-term successful use of ceramic materials in dental procedures, it is necessary to ensure reliable bonding of restorations to dental substrates. This can be achieved by the application of a proper luting cement and through additional surface conditioning. The present systematic review summarizes the most up-to-date evidence on the use of different surface modification methods to enhance the bond strength of dental ceramics to the hard tissues of the teeth. The authors of the review searched the Web of Science, Scopus, and MEDLINE databases to identify relevant articles published between 1 January 2010 and 1 January 2020. A total of 4892 records were identified, and after screening, the full text of 159 articles was evaluated, which finally resulted in the inclusion of 19 studies. The available reports were found to be heterogeneous in terms of materials and methodology, and therefore, only within-studies comparison was performed instead of comparison between studies. A statistically significant difference in the bond strength between the samples treated with different methods of surface conditioning, or between conditioned and nonconditioned samples, was revealed by most of the studies. Predominantly, the studies showed that a combination of mechanical and chemical methods was the most effective way of enhancing bond strength. Artificial aging and luting cement were also identified as the factors significantly influencing bond strength.


Subject(s)
Dental Cements/chemistry , Humans , Materials Testing , Surface Properties , Tensile Strength
9.
J Prosthet Dent ; 123(4): 647.e1-647.e7, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32115217

ABSTRACT

STATEMENT OF PROBLEM: Artificial denture teeth made of polymethyl methacrylate (PMMA) resin have good adhesion to the denture base but are relatively soft and have limited wear resistance during function. PURPOSE: The purpose of this in vitro study was to evaluate the influence of the addition of 2 inorganic nanofillers on the flexural strength, maximal displacement, elastic modulus, Isolde impact resistance, and Brinell hardness of acrylic resin denture teeth. MATERIAL AND METHODS: Heat polymerizing polymethyl methacrylate resin was mixed with silanized silica or silanized feldspar in concentrations of 5 wt%, 10 wt%, and 15 wt%. The first test was conducted after 24 hours of storage in laboratory conditions, and the second assessment was conducted after 3 months of storage in distilled water at 37 °C. The Brinell hardness was evaluated, and the elastic modulus and maximal displacement at fracture were calculated. The flexural strength and Isolde impact resistance were measured with a 3-point flexural test. Acrylic resin specimens without filler addition were used as a control group. Statistical analysis included 2-way ANOVA for independent variables (α=.05) and the Student t test for time-dependent changes (α=.05). These were performed with Statistica 12 software. RESULTS: The acrylic resin specimens modified with the addition of silanized feldspar had significantly higher Brinell hardness, elastic modulus, maximal displacement, and flexural strength and also had no adverse effect on Isolde impact resistance compared with the conventional acrylic resin. Silica filler increased the Brinell hardness and elastic modulus of acrylic resins but significantly reduced the flexural strength and Isolde impact resistance.


Subject(s)
Polymethyl Methacrylate , Silicon Dioxide , Aluminum Silicates , Dental Materials , Denture Bases , Dentures , Humans , Materials Testing , Pliability , Potassium Compounds , Stress, Mechanical , Surface Properties
10.
Molecules ; 25(10)2020 May 22.
Article in English | MEDLINE | ID: mdl-32455950

ABSTRACT

The purpose of this study was to compare the chemical composition and biological properties of Polish propolis. Ethanol, ethanol-hexane, hexane and hexane-ethanol extracts of propolis from three different regions of Poland were prepared. On the basis of the evaluation of their chemical composition as well as the extraction yield and free radical scavenging activity, the ethanol and hexane-ethanol extractions were proposed as the most effective methods. Subsequently, the biological properties of the extracts were evaluated to investigate the selectivity of an anticancer effect on tongue cancer cells in comparison to normal gingival fibroblasts. The obtained products demonstrated anticancer activity against tongue cancer cells. Additionally, when the lowest extract concentration (100 µg/mL) was applied, they were not cytotoxic to gingival fibroblasts. Finally, a possible anti-inflammatory potential of the prepared products was revealed, as reduced mitochondrial activity and proliferation of macrophages exposed to the extracts were observed. The results obtained indicate a potential of Polish propolis as a natural product with cancer-selective toxicity and anti-inflammatory effect. However, further studies are still needed to thoroughly explain the molecular mechanisms of its action and to obtain the promising health benefits of this versatile natural product.


Subject(s)
Antineoplastic Agents/pharmacology , Plant Extracts/pharmacology , Propolis/chemistry , Tongue Neoplasms/drug therapy , Antineoplastic Agents/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Cell Proliferation/drug effects , Fibroblasts/drug effects , Humans , Macrophages/drug effects , Mitochondria/drug effects , Plant Extracts/chemistry , Poland , Propolis/pharmacology , Tongue Neoplasms/pathology
11.
Adv Anat Embryol Cell Biol ; 227: 39-58, 2017.
Article in English | MEDLINE | ID: mdl-28980039

ABSTRACT

Cellular life strongly depends on the membrane ability to precisely control exchange of solutes between the internal and external (environmental) compartments. This barrier regulates which types of solutes can enter and leave the cell. Transmembrane transport involves complex mechanisms responsible for passive and active carriage of ions and small- and medium-size molecules. Transport mechanisms existing in the biological membranes highly determine proper cellular functions and contribute to drug transport. The present chapter deals with features and electrical properties of the cell membrane and addresses the questions how the cell membrane accomplishes transport functions and how transmembrane transport can be affected. Since dysfunctions of plasma membrane transporters very often are the cause of human diseases, we also report how specific transport mechanisms can be modulated or inhibited in order to enhance the therapeutic effect.


Subject(s)
Biological Transport , Cell Membrane/physiology , Ion Channels/metabolism , Electric Conductivity , Ion Channels/chemistry
12.
Dent Med Probl ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38686973

ABSTRACT

BACKGROUND: The mechanical reliability of occlusal splints and their long-term behavior are significant factors determining the clinical outcome of temporomandibular disorder (TMD) therapy. However, improvements are still needed in this area. OBJECTIVES: This in vitro study aimed to (1) compare the hardness and flexural properties of materials manufactured using 3 techniques for occlusal splint fabrication (conventional heat curing, thermoforming followed by light curing, and three-dimensional (3D) printing) and (2) analyze the effect of artificial aging on the properties of the materials. MATERIAL AND METHODS: A total of 120 disc-shaped specimens were manufactured for the Shore D hardness evaluation, and 120 bar-shaped specimens were fabricated for the flexural properties evaluation (n = 15 for each group). Each material was tested in 2 groups of specimens, non-aged and artificially aged (stored for 90 days in water at 37°C). Statistical differences were assessed using one-way or two-way parametric analysis of variance (ANOVA) with Tukey's or Sídák's post-hoc test, or the non-parametric KruskalWallis test with Dunn's post-hoc test. A p-value of less than 0.05 was considered statistically significant. RESULTS: The mechanical properties of the materials varied significantly. Among the non-aged materials, the 3D-printed resin exhibited the highest Shore D hardness (85.3D), but it decreased significantly after 90 days of water storage (80.4D, p < 0.0001). The unpolished heat curing acrylic showed the highest resistance to artificial aging (p = 0.0436). However, its hardness decreased significantly after polishing (81.0D vs. 83.4D, p = 0.0015). The conventional heat curing material also exhibited superior flexural properties (σ = 89.63 MPa, E = 2616 MPa). All tested materials were susceptible to deterioration due to aging. CONCLUSIONS: The conventional method of occlusal splint fabrication remains the optimal choice, particularly for long-term use. However, it is still necessary to develop materials that are resistant to aging in order to ensure successful clinical performance.

13.
J Membr Biol ; 246(10): 725-35, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23546012

ABSTRACT

The influence of electroporation on the Photofrin uptake and distribution was evaluated in the breast adenocarcinoma cells (MCF-7) and normal Chinese hamster ovary cells (CHO) lacking voltage-dependent channels in vitro. Photofrin was used at a concentration of 5 and 25 µM. The uptake of Photofrin was assessed using flow cytometry and fluorescence microscopy methods. Cells viability was evaluated with crystal violet assay. Our results indicated that electropermeabilization of cells, in the presence of Photofrin, increased the uptake of the photosensitizer. Even at the lowest electric field intensity (700 V/cm) Photofrin transport was enhanced. Flow cytometry results for MCF-7 cells revealed ~1.7 times stronger fluorescence emission intensity for cells exposed to Photofrin and electric field of 700 V/cm than cells treated with Photofrin alone. Photofrin was effective only when irradiated with blue light. Our studies on combination of photodynamic reaction with electroporation suggested improved effectiveness of the treatment and showed intracellular distribution of Photofrin. This approach may be attractive for cancer treatment as enhanced cellular uptake of Photofrin in MCF-7 cells can help to reduce effective dose of the photosensitizer and exposure time in this type of cancer, diminishing side effects of the therapy.


Subject(s)
Antineoplastic Agents/metabolism , Breast Neoplasms/metabolism , Dihematoporphyrin Ether/metabolism , Electroporation , Photosensitizing Agents/metabolism , Animals , CHO Cells , Cell Survival , Cricetinae , Cricetulus , Electroporation/methods , Female , Humans , MCF-7 Cells
14.
Materials (Basel) ; 16(6)2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36984116

ABSTRACT

(1) Background: In recent years, 3D printing has become a highly popular tool for manufacturing in various fields such as aviation, automobiles, plastics, and even medicine, including dentistry. Three-dimensional printing allows dentists to create high-precision models of teeth and jaw structure, and enables them to develop customized tools for patients' treatment. The range of resins used in dentistry is quite large, and this branch is developing rapidly; hence, studies comparing different resins are required. The present study aimed to compare the mechanical properties of two chosen resins used in dentistry. (2) Materials and methods: Ten specimens each of two types of 3D-printable resins (BioMed Amber and IBT, developed by Formlabs) were prepared. The samples were printed on a Formlabs Form 2 3D printer according to ISO standards. Samples for the compression test were rectangular in shape (10 ± 0.2 mm × 10 ± 0.2 mm × 4 ± 0.2 mm), while the samples used for the tensile test were dumbbell shaped (75 mm long, with 10 mm end width and 2 mm thickness). Tensile and compression tests of both materials were performed in accordance with the appropriate ISO standards. (3) Results: The BioMed Amber resin was more resistant to compression and tensile forces, thus implying that the resin could withstand higher stress during stretching, pulling, or pushing. The IBT resin was less resistant to such loads, and failure of this material occurred at lower forces than those for Biomed Amber. An ANOVA test confirmed that the observed differences were statistically significant (p < 0.001). (4) Conclusions: Based on the properties of both materials, the IBT resin could be better used as a tray for placing orthodontic brackets through an indirect bonding technique, while the BioMed Amber resin would be more useful as a surgical guide for placing dental implants and mini-implants. Further potential fields of application of the resins should be investigated.

15.
J Funct Biomater ; 14(5)2023 May 02.
Article in English | MEDLINE | ID: mdl-37233364

ABSTRACT

Currently, 3D print is becoming more common in all branches of medicine, including dentistry. Some novel resins, such as BioMed Amber (Formlabs), are used and incorporated to more advanced techniques. The aims of the study were to check whether or not polishing and/or artificial aging influences the properties of the 3D-printed resin. A total of 240 specimens of BioMed Resin were printed. Two shapes (rectangular and dumbbell) were prepared. Of each shape, 120 specimens were divided into four groups each (with no influence, after polishing only, after artificial aging only, and after both polishing and artificial aging). Artificial aging took place in water at the temperature of 37 °C for 90 days. For testing, the universal testing machine (Z10-X700, AML Instruments, Lincoln, UK) was used. The axial compression was performed with the speed of 1mm/min. The tensile modulus was measured with the constant speed of 5 mm/min. The highest resistance to compression and tensile test were observed in the specimens that were neither polished nor aged (0.88 ± 0.03 and 2.88 ± 0.26, respectively). The lowest resistance to compression was observed in the specimens that were not polished, but aged (0.70 ± 0.02). The lowest results of the tensile test were observed when specimens were both polished and aged (2.05 ± 0.28). Both polishing and artificial aging weakened the mechanical properties of the BioMed Amber resin. The compressive modulus changed much with or without polishing. The tensile modulus differed in specimens that were either polished or aged. The application of both did not change the properties when compared to the polished or aged probes only.

16.
J Funct Biomater ; 14(6)2023 May 25.
Article in English | MEDLINE | ID: mdl-37367259

ABSTRACT

Three-dimensional printing has become incorporated into various aspects of everyday life, including dentistry. Novel materials are being introduced rapidly. One such material is Dental LT Clear by Formlabs, a resin used for manufacturing occlusal splints, aligners, and orthodontic retainers. In this study, a total of 240 specimens, comprising two shapes (dumbbell and rectangular), were evaluated through compression and tensile tests. The compression tests revealed that the specimens were neither polished nor aged. However, after polishing, the compression modulus values decreased significantly. Specifically, the unpolished and nonaged specimens measured 0.87 ± 0.02, whereas the polished group measured 0.086 ± 0.03. The results were significantly affected by artificial aging. The polished group measured 0.73 ± 0.05, while the unpolished group measured 0.73 ± 0.03. In contrast, the tensile test proved that the specimens showed the highest resistance when the polishing was applied. The artificial aging influenced the tensile test and reduced the force needed to damage the specimens. The tensile modulus had the highest value when polishing was applied (3.00 ± 0.11). The conclusions drawn from these findings are as follows: 1. Polishing does not change the properties of the examined resin. 2. Artificial aging reduces resistance in both compression and tensile tests. 3. Polishing reduces the damage to the specimens in the aging process.

17.
Sci Rep ; 13(1): 11800, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37479853

ABSTRACT

This exploratory observational study aimed to evaluate whether the blood levels of serotonin and enzymes involved in serotonin synthesis are associated with sleep breathing parameters. A total of 105 patients were included in this study, who were subjected to single-night polysomnography with simultaneous audio-video recordings. Peripheral blood samples were collected to estimate the serum levels of serotonin, tryptophan hydroxylase 1 (TPH1), and aromatic l-amino acid decarboxylase (AADC). Results showed a negative correlation between blood serotonin levels, and oxygen desaturation index (ODI) (p = 0.027), central apnea (p = 0.044) and obstructive apnea (OA) (p = 0.032) scores. Blood TPH1 levels were negatively correlated with average (p = 0.003) and minimal saturation (p = 0.035) and positively correlated with apnea-hypopnea index (p = 0.010), OA (p = 0.049), and hypopnea index (p = 0.007) scores. A tendency to sleep-disordered breathing seemed to co-occur with lower blood serotonin and higher TPH1 levels.Clinical Trial Registration : www.ClinicalTrials.gov , identifier NCT04214561.


Subject(s)
Airway Obstruction , Sleep Apnea Syndromes , Sleep Apnea, Obstructive , Sleep Wake Disorders , Humans , Serotonin , Respiration , Sleep
18.
Dent Med Probl ; 60(3): 505-511, 2023.
Article in English | MEDLINE | ID: mdl-37227002

ABSTRACT

BACKGROUND: Three-dimensional (3D) printing technology has brought much innovation to medicine and has been successfully adopted in many areas of dentistry. Although 3D printing techniques are being increasingly used, their advantages and disadvantages still need to be investigated, particularly with regard to the materials used in dentistry. Dental materials should be biocompatible and non-cytotoxic, and have sufficient mechanical integrity in the oral environment in which they are intended for use. OBJECTIVES: The present work aimed to identify and compare the mechanical properties of three 3D-printable resins. The materials included IBT Resin, BioMed Amber Resin and Dental LT Clear Resin. The Formlabs Form 2 printer was used. MATERIAL AND METHODS: A tensile strength test was performed on 10 specimens of each resin. Tensile modulus was measured on 2-millimeter-thick dumbbell-shaped specimens, 75 mm in length and 10 mm in width. The 10 specimens of each resin were mounted between the grips of a universal testing machine (Z10-X700). RESULTS: The results showed that BioMed Amber specimens cracked easily, yet no deformation was observed. The amount of force used to test the tensility of the specimens was the lowest for IBT Resin, while it was the highest for Dental LT Clear Resin. CONCLUSIONS: IBT Resin was the weakest material, whereas Dental Clear LT Resin was the strongest.


Subject(s)
Amber , Dentistry , Humans
20.
Materials (Basel) ; 15(7)2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35407884

ABSTRACT

Effective disinfection of dental impressions is an indispensable requirement for the safety of dental personnel and patients. The ideal method should be not only effective but also convenient, cheap, and environmentally friendly. This study aimed to reliably evaluate the efficacy of ultraviolet C (UVC) radiation, gaseous ozone, and commercial liquid chemicals used for silicone dental impressions disinfection. These methods were applied to two types of elastomeric impression materials: condensation silicones and addition silicones of various consistency (putty, medium, and light). The antimicrobial effectiveness against Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans was evaluated in vitro by counting colony-forming units (CFU) on the surface of samples. The one-way ANOVA with a Tukey HSD test or the Kruskal-Wallis with a Dunn's test was performed. The results obtained revealed the efficacy of the proposed methods for disinfection of both C-silicones and A-silicones in most of the studied groups. Only one material (Panasil initial contact Light) was not effectively disinfected after UVC irradiation or ozone application. In conclusion, the potential of each disinfection method should be evaluated separately for each material. Moreover, in further research, the possible influence of the proposed methods on the physical properties of the impression materials should be thoroughly investigated.

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