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1.
Sci Prog ; 107(1): 368504241228964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489928

RESUMO

Background/Aim: The ideal treatment of tooth avulsion is replantation. However, replanting teeth may lead to root resorption. Fibroblast growth factor-2 (FGF-2) is a cytokine that plays an important role in wound repair and tissue regeneration. Recently, FGF-2 has been studied a potential regenerative agent to prevent root resorption and ankylosis. The aim of this review is to analyze and summarize the currently available literature focusing on using FGF-2 based regenerative modalities to improve the outcomes of tooth replantation. Materials and Methods: An electronic search was conducted via PubMed/Medline, Google Scholar and ISI Web of Knowledge, using the Medical Subject Headings (MeSH) terms "Basic fibroblast growth factor," "Fibroblast growth factor-2," "tooth replantation," and "replantation" for studies published between January 2001 and June 2021. Data was extracted and quality assessment was carried using the ARRIVE guidelines. Results: Nine animal studies were included in this review. In six studies, FGF-2 had a favorable effect on the tissue regeneration around roots of replanted teeth when compared to other treatment groups. However, quality assessment of the studies revealed many sources of bias and deficiencies in the studies. Conclusions: Within the limitations of this study, it may be concluded that FGF-2 may improve the outcomes of delayed replantation of avulsed teeth. However, more long-term animal studies, with improved experimental designs, and clinical trials are required to determine the clinical potential of the growth factor in improving the outcomes of delayed tooth replantation.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Reabsorção da Raiz , Avulsão Dentária , Animais , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Reabsorção da Raiz/prevenção & controle , Fatores de Tempo , Reimplante Dentário
2.
Heliyon ; 9(12): e23061, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38076061

RESUMO

Objective: This study aims to determine the prevalence and degree of Burnout during the COVID 19 pandemic in practicing Pakistani dentists. Introduction: The COVID-19 pandemic has significantly impacted dental practices worldwide, leading to increased stress and burnout among dental practitioners. Burnout, characterized by emotional exhaustion, depersonalization, and reduced personal accomplishment, can have detrimental effects on the quality of care and patient safety. Previous studies have shown high rates of burnout among healthcare workers, including dentists. The pandemic has added new challenges, such as financial losses and increased costs due to safety protocols. Recognizing and managing burnout is crucial to mitigate its severe consequences. By understanding the prevalence of burnout in this unique context, strategies can be developed to support dental practitioners and improve their well-being. Methods: A cross-sectional study was conducted using a 22-items based validated Maslach Burnout Inventory. The study was conducted between July and September 2021. Practicing dentists across Pakistan were approached via social media platforms. The questions were answered on a 7-point Likert scale. The sums of the scores were used as the evaluation criteria. Data analysis was done using SPSS version 24. Shapiro Wilk test was used to check normality of data. Mann Whitney U and Kruskal Wallis tests were utilized to analyze the differences in the prevalence of burnout amongst the different demographic groups. A P-value of <0.05 was considered as statistically significant. Results: Total of 282 dentists responded with 116 (41.1 %) male and 166 (58.9 %) female. Majority of the respondents were postgraduate residents (24.8 %), 47.9 % of the practitioners had 0-3 years of work experience, 48.6 % of the respondents were practicing in the Federal region, and 62.8 % of the subjects were between the age of 25-34. Emotional exhaustion was the major dimension of burnout identified in our study with 47.5 % of the population reporting high levels, while only 23 % of the population showed high levels of depersonalization and 29.4 % showed low sense of personal accomplishment. Conclusion: This study indicates a considerable percentage of burnout in the chosen sample. The mean scores of Emotional Exhaustion, Depersonalization and Diminished sense of personal accomplishment were all found to be in the moderate range, and that appropriate measures should be taken to manage it.

3.
Int J Dent ; 2023: 4179210, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111754

RESUMO

Optical coherence tomography (OCT) is an optics-based imaging technique, which may be called an "optical biopsy." It can be used to acquire structural information about a tissue at a resolution comparable to histopathology. OCT is based on the principle of low-coherence interferometry where near-infrared (NIR) light is shown on a tissue sample and then cross-sectional images are obtained based on backscattered light and echo time delay. Two main types of OCT are characterized as time-domain OCT (TD-OCT) and Fourier-domain OCT (FD-OCT). The applications of OCT in dentistry can be broadly divided into two groups, i.e., assessment of pathologies and assessment of surfaces and interfaces. Lately, OCT has made its transition from experimental laboratories to mainstream clinical applications. Starting from the short-term training courses, clinicians working in specialities like oral pathology, oral medicine, and oral implantology may find it a useful tool for their practices. It is now clear that OCT will be considered a gold standard diagnostic tool for the detection and characterization of several conditions and lesions of the orofacial region. However, the next challenge will be to incorporate it into the undergraduate and postgraduate curriculum and train dental healthcare staff in the use of these devices.

4.
Cureus ; 15(10): e47271, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021485

RESUMO

INTRODUCTION: The scholarly productivity of a faculty member can be measured through several indicators including annual appraisals, feedback, and the number of publications per year. The present study aims to assess the association of quantitative research measures and academic ranks in Australian and New Zealand dental schools. METHODS: It was an analytical observational cross-sectional study. Full-time faculty members working in Australia and New Zealand's dental schools were discovered on official websites. Various bibliometric parameters including h-index, total number of citations, total number of publications, and maximum number of sources of a single publication were analyzed. Spearman rank correlation was used to determine the correlation between bibliometric variables and academic ranks (lecturer, assistant professor, professor). The Mann-Whitney U test was used to compare bibliometric parameters among departments (Basic and Clinical) and gender (male and female). RESULTS: Through the present search strategy, 207 full-time faculty members were identified, of which 12 were from New Zealand, and 195 were from Australia. Among them, 130 (62.8%) were male and 70 (33.8%) were female faculty members. There was a positive correlation of all bibliometric parameters with academic ranks (p = 0.001). There was no statistical difference between the two countries for academic parameters (p > 0.05). Male faculty members showed significantly higher academic productivity than female members in Australian dental schools (p = 0.001). CONCLUSION: These bibliometric parameters and other educational parameters can be considered for determining faculty promotions. These bibliometric parameters appear to be suitable metrics for assessing research productivity, impact, and visibility.

5.
Biomolecules ; 13(10)2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37892210

RESUMO

BACKGROUND: The emergence of dental implants has revolutionized the management of tooth loss. However, the placement of clinical implants exposes them to complex oral environment and numerous microscopic entities, such as bacteria. Cold atmospheric plasma (CAP) is often used to treat the surfaces of dental implants, which alters morphological features and effectively reduces bacterial load. PURPOSE: This systematic review aims to assess the existing literature on the bactericidal properties of CAP when used on various kinds of dental implant surfaces. REVIEW METHOD: An in-depth examination of MEDLINE/PubMed and EMBASE was performed to identify relevant studies, with the most recent search conducted in May 2023. Studies were selected based on their exploration of CAP's effects on dental implants compared to control groups, focusing on CAP's bactericidal efficacy. However, studies that lacked a control group or that failed to measure bactericidal effects were excluded. RESULTS: After applying the selection criteria, 15 studies were ultimately included in the systematic review. The collected data suggest that CAP can effectively reduce bacterial loads on dental implant surfaces, including pathogens like Streptococcus mitis and Staphylococcus aureus. Furthermore, CAP appears to combat biofilms and plaques that are key contributors to periimplantitis. CONCLUSION: CAP emerges as a promising treatment option, exhibiting significant bactericidal activity on dental implant surfaces. CAP can decrease the rates of bacterial biofilm and plaque formation, leading to improved outcomes for dental implant patients.


Assuntos
Implantes Dentários , Gases em Plasma , Humanos , Gases em Plasma/farmacologia , Bactérias , Biofilmes , Carga Bacteriana , Antibacterianos
6.
Polymers (Basel) ; 15(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37571151

RESUMO

An ideal denture base must have good physical and mechanical properties, biocompatibility, and esthetic properties. Various polymeric materials have been used to construct denture bases. Polymethyl methacrylate (PMMA) is the most used biomaterial for dentures fabrication due to its favorable properties, which include ease of processing and pigmenting, sufficient mechanical properties, economy, and low toxicity. This article aimed to comprehensively review the current knowledge about denture base materials (DBMs) types, properties, modifications, applications, and construction methods. We searched for articles about denture base materials in PubMed, Scopus, and Embase. Journals covering topics including dental materials, prosthodontics, and restorative dentistry were also combed through. Denture base material variations, types, qualities, applications, and fabrication research published in English were considered. Although PMMA has several benefits and gained popularity as a denture base material, it has certain limitations and cannot be classified as an ideal biomaterial for fabricating dental prostheses. Accordingly, several studies have been performed to enhance the physical and mechanical properties of PMMA by chemical modifications and mechanical reinforcement using fibers, nanofillers, and hybrid materials. This review aimed to update the current knowledge about DBMs' types, properties, applications, and recent developments. There is a need for specific research to improve their biological properties due to patient and dental staff adverse reactions to possibly harmful substances produced during their manufacturing and use.

7.
J Taibah Univ Med Sci ; 18(6): 1299-1310, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37275952

RESUMO

Metformin is a versatile drug with numerous medical uses. It is known primarily as an anti-hyperglycemic drug that has become the main oral blood-glucose-lowering medication for managing type 2 diabetes mellitus globally. Its use has been reported in a variety of oral conditions and dentistry in general. Recent clinical trials have indicated the effectiveness of adjunct topical application of metformin in improving the periodontal parameters of patients with diabetes and periodontitis. Additionally, studies have suggested that metformin stimulates odontogenic differentiation and mineral synthesis of stem cells in the tooth pulp. Metformin also stimulates osteoblast proliferation, decreases osteoclast activity and exerts regenerative effects on periodontal bone, thus making it a viable candidate for periodontal regeneration. Metformin monotherapy significantly enhances osseointegration of endosseous implants and has been reported to have anti-cancer effects on oral squamous cell carcinoma by impeding tumor progression. Animal studies have indicated that metformin improves orthodontic tooth movement and resists orthodontic appliance corrosion. This narrative review aims to provide a current summary of research highlighting the prospective uses of metformin in dentistry.

8.
Int J Biol Macromol ; 241: 124623, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37119888

RESUMO

Hydrogels which become increasingly important in the biomedical field are composed of a three-dimensional hydrophilic network. Pure hydrogels are usually weak and brittle; therefore, reinforcements are assimilated into the hydrogel structure to improve the mechanical strength of the hydrogels. However, even if mechanical properties are enhanced, drapability remains an issue. In that regard, natural fiber-reinforced composite hydrogel fibers for wound dressing application are investigated in this study. Kapok and hemp fibers were used as reinforcement to improve the strength of hydrogel fibers. The properties of the prepared composite hydrogel fibers were studied with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and differential scanning calorimeter (DSC). The effect of alginate concentration and fiber weight percent on the mechanical characteristics and water absorbency was studied. Diclofenac sodium drug was loaded in the hydrogel fibers and investigated the drug release as well as antibacterial characteristics. Both fibers' reinforcement enhanced the strength of the alginate hydrogel fiber, but hemp reinforcement showed better mechanical properties. Kapok reinforcement resulted in a maximum tensile strength of 174 cN (1.24 % elongation) and 432 % exudate absorbency, while hemp reinforcement resulted in 185 cN (1.48 % elongation) and 435 % exudate absorbency. Statistical analysis revealed significant effects of sodium alginate concentration on tensile strength (p-value 0.042) and exudate absorbency (p-value 0.020) and of reinforcement (wt%) on exudate absorbency (p-value 0.043). Therefore, these composite hydrogel fibers with improved mechanical properties are capable of drug release and exhibit antibacterial effectiveness, making them a promising option for use as wound dressings.


Assuntos
Diclofenaco , Hidrogéis , Hidrogéis/química , Diclofenaco/farmacologia , Alginatos/química , Cicatrização , Bandagens , Antibacterianos/farmacologia
9.
SAGE Open Med ; 11: 20503121231158981, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909796

RESUMO

Coronavirus disease 2019 is a severe communicable pulmonary medical problem that has been a challenging disease for everyone in the globe, but vaccines development and administration against this severe acute respiratory syndrome-inducing disease (coronavirus disease 2019) are currently yielding fabulous results. The mean duration of the coronavirus disease 2019 pandemic for this study spanned from 2020 until 2022. These manifestations are accompanied by symptoms of respiratory tract illnesses such as non-productive cough, sore throat, and nasal discharge. Relevant reviews on coronavirus disease 2019 manifestations and outcomes, consisting mainly of the infections/outbreaks, experimental information, and pre- and post-serovaccination details that occurred, were described. After a typical vaccination course, the study aims to summarize and understand more about the effectiveness of exercise on the pre-and post-coronavirus disease 2019 vaccination and its implementations. Physical activity is an immunological function adjuvant to decrease communicable disease risk and enhance immunity post-viral infection vaccination. Moderate-intensity resistance exercisesession directly before getting the influenza vaccine decreases vaccine responses in older adults, such as redness, pain, or inflammation at the injection spot or other adverse consequences compared to the inactive circumstance. However, it was reported that exercise after a shot is generally safe as long as vaccinated people feel well enough. Though exercise before or after vaccination has no negative impact on the protection afforded by the vaccine, people can exercise immediately after receiving the vaccine, as any changes in blood flow will not affect the vaccine's response. One episode of light-to-moderate-intensifying exercise after vaccination may improve the antibody reactions to influenza or the coronavirus disease 2019 vaccine. Vaccination administered pre- and post-regular exercise is an effective approach for boosting antibody responses due to its immunostimulant effects. Future research should investigate how different vaccine antibodies respond to low, moderate, and high physical activity levels.

10.
Biomimetics (Basel) ; 8(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36648805

RESUMO

During the last 10 years, various companies have marketed different "bulk-fill" resin dental composites for the restoration of posterior stress-bearing teeth; however, the impact of acidic conditions on these relatively newer materials has not been thoroughly investigated. Therefore, an attempt was made to evaluate the effect of acidic beverages on the mechanical biomimetic characteristics of four bulk-fill and one conventional nanohybrid resin-based dental composites (RBCs). The specimens of each RBC were stored in two acidic beverages namely 'Orange Juice' and 'Coca-Cola', whereas 'dry' and 'distilled water' storage of specimens served as controls. After 1 week of storage, flexural and surface hardness properties of specimens were determined using a universal testing machine and Vickers hardness tester, respectively. In general, the 'Coca-Cola' beverage caused the greatest degradation of flexural strength, flexural modulus, and surface hardness characteristics in all RBCs in contrast to the 'dry', 'distilled water' controls and 'Orange Juice' storage conditions. However, the overall mechanical biomimetic performance of nanohybrid RBCs was relatively better than all other bulk-fill RBCs and may, therefore, be considered a suitable candidate for the restoration of posterior stress-bearing permanent dentition.

11.
Dent Mater ; 39(2): 141-151, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36604257

RESUMO

OBJECTIVE: This review aimed to highlight the insight into adhesion aspects within the components of the glass FRC (i.e., fiber and matrix) and between resin luting material and the glass FRC construction. METHODS: The fundamentals of semi-interpenetrating polymer network (semi-IPN) based FRCs and their advantages in forming a solid adhesive interface with indirect FRC restoration, dental adhesive, and luting cement are elaborated. The important resin matrix systems and glass fibers used in FRCs are discussed. This is principally based on a survey of the literature over Medline/PubMed, Web of Science, and Scopus databases and a review of the relevant studies and publications in scientific papers in international peer-reviewed journals for the specific topic of biomaterials science. The keywords used for the search approach were: adhesion, fiber-reinforced composite, glass fiber, and semi-interpenetrating polymer network. RESULTS: The polymer matrix systems of semi-IPN-based FRCs and formation of secondary-IPN layer are pivotal for bonding of multiphasic indirect dental constructs and repair. Additionally, describing areas of indication for FRCs in dentistry, explaining the adhesion aspects of FRC for the cohesion of the material itself, and for obtaining durable adhesion when the FRC construct is luted to tooth and remaining dentition. Current progress in the field of FRC research and future directions are summarized and presented. SIGNIFICANCE: By understanding the isotropic-anisotropic nature of fibers and the interfacial adhesion within the components of the FRC; between resin cement and the FRC construction, the clinically successful FRC-based multiphasic indirect tooth construct can be achieved. The interfacial adhesion within the components of the FRC and between resin luting material and the FRC construction play a key role in adhesion-based unibody dental restorations.


Assuntos
Resinas Compostas , Colagem Dentária , Cimentos de Resina , Polímeros , Odontologia , Vidro , Teste de Materiais , Materiais Dentários
12.
Biomimetics (Basel) ; 7(4)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36546929

RESUMO

In the last few decades, biomimetic concepts have been widely adopted in various biomedical fields, including clinical dentistry. Endodontics is an important sub-branch of dentistry which deals with the different conditions of pulp to prevent tooth loss. Traditionally, common procedures, namely pulp capping, root canal treatment, apexification, and apexigonesis, have been considered for the treatment of different pulp conditions using selected materials. However, clinically to regenerate dental pulp, tissue engineering has been advocated as a feasible approach. Currently, new trends are emerging in terms of regenerative endodontics which have led to the replacement of diseased and non-vital teeth into the functional and healthy dentine-pulp complex. Root- canal therapy is the standard management option when dental pulp is damaged irreversibly. This treatment modality involves soft-tissue removal and then filling that gap through the obturation technique with a synthetic material. The formation of tubular dentine and pulp-like tissue formation occurs when stem cells are transplanted into the root canal with an appropriate scaffold material. To sum up tissue engineering approach includes three components: (1) scaffold, (2) differentiation, growth, and factors, and (3) the recruitment of stem cells within the pulp or from the periapical region. The aim of this paper is to thoroughly review and discuss various pulp-regenerative approaches and materials used in regenerative endodontics which may highlight the current trends and future research prospects in this particular area.

13.
Biomed Res Int ; 2022: 6544292, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36567909

RESUMO

Introduction/Objectives. Enterococcus faecalis has been implicated in infections of treated root canals. Current irrigants and intracanal medicaments cannot eliminate E. faecalis completely from the root canal. Silver diamine fluoride (SDF) prevents caries by promoting remineralization and exerting an antibacterial effect. Studies suggest that SDF may possess antibacterial properties against E. faecalis. The purpose of this review is to systematically and critically analyze the literature, focusing on the use of SDF as an intracanal medicament or irrigant, when compared to other antibacterial agents. Data/Sources. The focused question was "Is the antibacterial effect of SDF against E. faecalis better than other intracanal medicaments and irrigants?" Using the keywords ((silver diamine fluoride) AND (Enterococcus faecalis)) AND ((sodium hypochlorite) OR (NaOCl) OR (chlorhexidine) OR (calcium hydroxide) OR (Ca(OH)2)), an electronic search was conducted on the following databases: PubMed/MEDLINE, ISI Web of Science, Scopus, EMBASE, and Google Scholar. The clinical trial registers ClinicalTrials.gov and CONTROL were also searched using the same keywords. General characteristics and outcomes were extracted, and quality of the studies was assessed using the Preferred Reporting Items for Laboratory studies in Endodontology (PRILE) guidelines. Study Selection. Six articles (five in vitro studies and one ex vivo study) were included in this systematic review. In the majority of the studies, SDF had equal or better antibacterial efficacy against E. faecalis compared to calcium hydroxide, sodium hypochlorite, and chlorhexidine. However, the majority of the studies did not fulfill several items in the PRILE criteria and had numerous sources of bias. Conclusions. Within the limitations of the systematic review and the studies reviewed, SDF may be effective against E. faecalis and therefore could be used as an intracanal medicament and/or irrigant to prevent reinfections of the root canals and improve the outcomes of endodontic treatment. However, animal and clinical studies should be carried out to determine the efficacy of SDF in endodontics. Trial Registration. The protocol for this review was registered on PROSPERO. Registration number: CRD42021224741.


Assuntos
Anti-Infecciosos , Clorexidina , Animais , Clorexidina/farmacologia , Enterococcus faecalis , Hipoclorito de Sódio , Hidróxido de Cálcio/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cavidade Pulpar
14.
Polymers (Basel) ; 14(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36365700

RESUMO

In this study, cotton-reinforced alginate hydrogel fibers were successfully synthesized using the wet spinning technique to improve hydrogel fibers' mechanical strength and durability. Structural, chemical, and mechanical properties of the prepared fibers were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray Diffraction, differential scanning calorimeter, and single fiber strength tester. Based on the results obtained from fourier transform infrared spectroscopy and x-ray Diffraction, cotton fibers have been successfully incorporated into the structure of the hydrogel fibers. It was seen from the differential scanning calorimeter results that the incorporation of fibers in the structure even enhanced the thermal stability of the fiber and is viable to be implanted in the human body. Cotton reinforcement in alginate hydrogel fibers increases the modulus up to 56.45 MPa providing significant stiffness and toughness for the hydrogel composite fiber. The tenacity of the fibers increased by increasing the concentration of alginate from 2.1 cN/Tex (1% w/v) to 8.16 cN/Tex (1.5% w/v). Fiber strength increased by 26.75% and water absorbance increased by 120% by incorporating (10% w/w) cotton fibers into the fibrous structure. It was concluded that these cotton-reinforced alginate hydrogel fibers have improved mechanical properties and liquid absorption properties suitable for use in various biomedical applications.

15.
Biosensors (Basel) ; 12(11)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36354437

RESUMO

Electrochemical biosensors are a family of biosensors that use an electrochemical transducer to perform their functions. In recent decades, many electrochemical biosensors have been created for pathogen detection. These biosensors for detecting infections have been comprehensively studied in terms of transduction elements, biorecognition components, and electrochemical methods. This review discusses the biorecognition components that may be used to identify pathogens. These include antibodies and aptamers. The integration of transducers and electrode changes in biosensor design is a major discussion topic. Pathogen detection methods can be categorized by sample preparation and secondary binding processes. Diagnostics in medicine, environmental monitoring, and biothreat detection can benefit from electrochemical biosensors to ensure food and water safety. Disposable and reusable biosensors for process monitoring, as well as multiplexed and conformal pathogen detection, are all included in this review. It is now possible to identify a wide range of diseases using biosensors that may be applied to food, bodily fluids, and even objects' surfaces. The sensitivity of optical techniques may be superior to electrochemical approaches, but optical methods are prohibitively expensive and challenging for most end users to utilize. On the other hand, electrochemical approaches are simpler to use, but their efficacy in identifying infections is still far from satisfactory.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Transdutores , Anticorpos
16.
Materials (Basel) ; 15(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35955317

RESUMO

Nowadays, a large variety of prostheses both in medicine and dentistry are increasingly made of polymers and polymer-based materials [...].

17.
Molecules ; 27(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36014357

RESUMO

It is always difficult to avoid subjectivism in the assessment of the properties of prosthodontics materials due to the ambiguity in the evaluation criteria of dental research [...].


Assuntos
Materiais Biocompatíveis , Prostodontia
18.
Materials (Basel) ; 15(14)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35888420

RESUMO

The aim of this study was to assess and compare the stress-strain pattern of zygomatic dental implants supporting different superstructures using 3D finite element analysis (FEA). A model of a tridimensional edentulous maxilla with four dental implants was designed using the computer-aided design (CAD) software. Two standard and two zygomatic implants were positioned to support the U-shaped bar superstructure. In the computer-aided engineering (CAE) software, different materials have been simulated for the superstructure: cobalt-chrome (CoCr) alloy, titanium alloy (Ti), zirconia (Zr), carbon-fiber polymers (CF) and polyetheretherketone (PEEK). An axial load of 500 N was applied in the posterior regions near the zygomatic implants. Considering the mechanical response of the bone tissue, all superstructure materials resulted in homogeneous strain and thus could reconstruct the edentulous maxilla. However, with the aim to reduce the stress in the zygomatic implants and prosthetic screws, stiffer materials, such Zr, CoCr and Ti, appeared to be a preferable option.

19.
Biomimetics (Basel) ; 7(3)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35892372

RESUMO

The objectives of this study were to investigate the pH of common beverages and to evaluate the effects of common acidic beverages on the surface hardness and weight loss of human tooth specimens. A total of 106 beverages were conveniently purchased from supermarkets in Karachi, Pakistan. Prior to evaluation, beverages were refrigerated or stored at room temperature in accordance with the manufacturers' recommendations. Beverages were categorized into six groups: 'Sports and Energy drinks', 'Water', 'Fruit Juices and Drinks', 'Sodas', 'Milk and Flavored Milk' and 'Teas and Coffee'. Using a pH meter, the pH of each beverage was measured in triplicate at room temperature. In addition, the influence of five highly acidic beverages on the weight loss and surface hardness of human tooth specimens was evaluated using gravimetric analysis and the Vickers hardness tester, respectively. 'Sports and Energy drinks', 'Fruits Juices and Drinks' and 'Sodas' were the most acidic beverage categories, with a pH range of 3.00−5.00. A total of 33% of beverages tested in this study were highly acidic (pH less than 4.00), 29% of beverages were moderately acidic (pH 4.00−4.99) and 31% were mildly acidic (pH 5.00−6.99). Significant weight loss was observed in all immersed specimens compared to control counterparts (p < 0.05). Similarly, for surface hardness, five highly acidic beverages (Red Bull, Pepsi, Apple Cidra, Tang Mosambi and Tang Orange) significantly decreased the surface hardness of specimens (p < 0.05). The pH levels of commonly available beverages in Pakistan are highly acidic, which may encourage loss of minerals from teeth; hence, affecting their surface hardness.

20.
Healthcare (Basel) ; 10(8)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893195

RESUMO

This systematic review aimed to investigate the relation between orthodontic treatment (OT) and the incidence of the gingival black triangle (GBT) after completing treatment with a fixed orthodontic appliance, as well as the associated risk factors and the level of alveolar bone. Electronic and hand searches were conducted in three electronic databases for relevant articles published up to March 2022. Retrieved articles went through a two-step screening procedure, and the risk of bias (RoB) was assessed by the Joanna Briggs Institute checklists. The incidence of GBT after OT was set as the primary outcome, while the secondary outcomes were the risk factors associated with GBT and alveolar bone loss following OT. Out of 421 papers, 5 were selected for the final analysis. The RoBs of three studies were moderate and the remaining two were low. The incidence of GBT following OT ranged from 38% to 58%. In addition, three studies reported that alveolar bone loss was reduced significantly following OT and associated with GBT, while one study found the opposite. Regarding the risk factors associated with GBT, the reported results attributed GBT to several factors including age, tooth-related factors, treatment duration, and soft tissue factors. The analysis indicates an increased incidence of GBT following OT; however, a firm conclusion cannot be drawn. Additionally, it was not possible to reach a consensus on risk factors associated with GBT due to the heterogeneity of the data. Therefore, further randomized clinical trials are highly recommended to draw a firm conclusion.

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