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1.
J Prosthet Dent ; 130(2): 179-186, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34740459

RESUMO

STATEMENT OF PROBLEM: Minimally invasive dentistry is a technique for the maximal preservation of healthy tooth structures and has been a focus of attention in dental research. However, a detailed bibliometric analysis focusing on research related to minimally invasive dentistry is lacking. PURPOSE: The purpose of this bibliometric analysis was to analyze leading countries and organizations and to identify the preferred journals, the most productive authors, and the most commonly used keywords in the field of minimally invasive dentistry. MATERIAL AND METHODS: The search was performed by using the Scopus database, and publications pertinent to the field of minimally invasive dentistry from 1994 to 2021 were identified. A bibliometric analysis with reference to citations and documents, authors, journals, and keywords was performed. A total of 391 articles published in Scopus indexed journals between 1994 and January 2021 were analyzed by using a software program. RESULTS: A continuing yet steady increase in research publications was identified, with a substantial increase in publications since 2013. The United States and Germany were the countries that published the most articles (98 and 46, respectively), articles that received 1877 and 806 citations, respectively. Cardiff University, UK, was the most productive organization that received 212 citations. The most highly cited articles were from the Q1 category. Blum from King's College London was the highest-cited author in this field. CONCLUSIONS: Considerable advancement has been made in minimally invasive dentistry, as demonstrated by the increase in the number of publications linked with collaboration among various authors, nations, and institutes. This citation analysis gives a perspective on the progress of research in the field of minimally invasive dentistry and allows identification of the most significant and pertinent research areas.


Assuntos
Bibliometria , Eficiência , Humanos , Alemanha , Odontologia , Londres
2.
Sci Rep ; 10(1): 15520, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968120

RESUMO

Technological advances have made it possible to examine dental resin composites using 3D nanometer resolution. This investigation aims to characterize existing dental nano-hybrid and micro-hybrid resin composites through comparing and contrasting nano-computed tomography (nano-CT) with micro-CT and high-resolution SEM images. Eight commercially available and widely used dental resin composites, 2 micro-hybrid and 6 nano-hybrid were researched. Cured samples were examined and characterized using nano-CT (resolution 450 nm) and compared with micro-CT images (resolution 2 µm). Acquired images were reconstructed and image analysis was carried out to determine porosity and pore morphology. A comprehensive comparison of scanning micrograph images unsurprisingly revealed that the nano-CT images displayed greater detail of the ultrastructure of cured dental resin composites. Filler particle diameters and its volumes were lower when measured using nano-CT, porosity being higher where analysed at higher resolution. There were large variations between the examined materials. Fewer voids were found in Tetric EvoCeram and IPS Empress Direct, the smallest pores being found in Universal XTE and Tetric EvoCeram. Nano-CT was successfully used to investigate the morphology of dental resin composites and showed that micro-CT gives a lower porosity and pore size but overestimates filler particle size. There were large discrepancies between the tested composites. Evidence of porosities and pores within a specimen is a critical finding and it might have a detrimental effect on a material's clinical performance.


Assuntos
Resinas Acrílicas/química , Resinas Compostas/química , Poliuretanos/química , Resinas Sintéticas/química , Microtomografia por Raio-X/métodos , Microscopia Eletrônica de Varredura , Nanotecnologia/métodos
3.
J Mech Behav Biomed Mater ; 110: 103927, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32957222

RESUMO

OBJECTIVE: Here we describe a novel formulation, based on quaternary ammonium (QA) and riboflavin (RF), which combines antimicrobial activities and protease inhibitory properties with collagen crosslinking without interference to bonding capabilities, was investigated. METHODS: Experimental adhesives modified with different fractions of dioctadecyldimethyl ammonium bromide quaternary ammonium and riboflavin (QARF) were formulated. Dentine specimens were bonded to resincomposites with control or the experimental adhesives to be evaluated for bond strength, interfacial morphology, micro-Raman analysis, nano-CT and nano-leakage expression. In addition, the antibacterial and biocompatibilities of the experimental adhesives were investigated. The endogenous proteases activities and their molecular binding-sites were studied. RESULTS: Modifying the experimental adhesives with QARF did not adversely affect micro-tensile bond strength or the degree of conversion along with the demonstration of anti-proteases and antibacterial abilities with acceptable biocompatibilities. In general, all experimental adhesives demonstrated favourable bond strength with increased and improved values in 1% QARF adhesive at 24 h (39.2 ± 3.0 MPa) and following thermocycling (34.8 ± 4.3 MPa). SIGNIFICANCE: It is possible to conclude that the use of QARF with defined concentration can maintain bond strength values when an appropriate protocol is used and have contributed in ensuring a significant decrease in microbial growth of biofilms. Incorporation of 1% QARF in the experimental adhesive lead to simultaneous antimicrobial and anti-proteolytic effects with low cytotoxic effects, acceptable bond strength and interfacial morphology.


Assuntos
Antibacterianos , Colagem Dentária , Antibacterianos/farmacologia , Colágeno , Dentina , Adesivos Dentinários , Teste de Materiais , Cimentos de Resina , Resistência à Tração
4.
Int J Mol Sci ; 19(2)2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29385727

RESUMO

Electrospinning has been used for decades to generate nano-fibres via an electrically charged jet of polymer solution. This process is established on a spinning technique, using electrostatic forces to produce fine fibres from polymer solutions. Amongst, the electrospinning of available biopolymers (silk, cellulose, collagen, gelatine and hyaluronic acid), chitosan (CH) has shown a favourable outcome for tissue regeneration applications. The aim of the current review is to assess the current literature about electrospinning chitosan and its composite formulations for creating fibres in combination with other natural polymers to be employed in tissue engineering. In addition, various polymers blended with chitosan for electrospinning have been discussed in terms of their potential biomedical applications. The review shows that evidence exists in support of the favourable properties and biocompatibility of chitosan electrospun composite biomaterials for a range of applications. However, further research and in vivo studies are required to translate these materials from the laboratory to clinical applications.


Assuntos
Quitosana/química , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Animais , Humanos
5.
Materials (Basel) ; 10(6)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28772963

RESUMO

Chitosan (CHS) is a very versatile natural biomaterial that has been explored for a range of bio-dental applications. CHS has numerous favourable properties such as biocompatibility, hydrophilicity, biodegradability, and a broad antibacterial spectrum (covering gram-negative and gram-positive bacteria as well as fungi). In addition, the molecular structure boasts reactive functional groups that provide numerous reaction sites and opportunities for forging electrochemical relationships at the cellular and molecular levels. The unique properties of CHS have attracted materials scientists around the globe to explore it for bio-dental applications. This review aims to highlight and discuss the hype around the development of novel chitosan biomaterials. Utilizing chitosan as a critical additive for the modification and improvement of existing dental materials has also been discussed.

6.
Prog Orthod ; 18(1): 5, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28133716

RESUMO

Diabetes mellitus (DM) may adversely affect periodontal tissues during orthodontic tooth movement (OTM). The aim of this review is to systematically analyze and review animal studies investigating the effect of DM on periodontal tissues during OTM. An electronic search was conducted via PubMed/Medline, Google Scholar, Embase, ISI Web of Knowledge, and Cochrane Central Register of Controlled Trials (CONTROL) using the keywords "diabetes," "orthodontics," and "tooth movement" for studies published between January 2000 and August 2016. After elimination of duplicate items, the primary search resulted in 89 articles. After exclusion of irrelevant articles on the basis of abstract and title, full texts of 25 articles were read to exclude additional irrelevant studies. Seven animal studies were included in this review for qualitative analysis. When compared to healthy animals, more bone resorption and diminished bone remodeling were observed in diabetic animals in all studies. Furthermore, DM decreased the rate of OTM in one study, but in another study, DM accelerated OTM. DM may adversely affect bone remodeling and tooth movement during application of orthodontic forces. However, a number of potential sources of bias and deficiencies in methodology are present in studies investigating the association between OTM and DM. Hence, more long-term and well-designed studies are required before the exact mechanism and impact of DM on outcomes of orthodontic treatment is understood.


Assuntos
Diabetes Mellitus Experimental/complicações , Doenças Periodontais/etiologia , Técnicas de Movimentação Dentária/efeitos adversos , Animais , Doenças Periodontais/patologia , Periodonto/patologia , Ratos
7.
J Investig Clin Dent ; 8(4)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27782374

RESUMO

AIM: The aim of the present study was to evaluate the effect of chemical disinfection, autoclave, and microwave sterilization on some of the key properties of elastomers. METHODS: Five polyvinylsiloxane elastomeric impression materials were evaluated. Forty samples were fabricated from each material. The samples were randomly selected and assigned to four experimental groups with 50 samples each: group I, control; group II,chemical disinfection; group III, autoclave sterilization; and group IV, microwave sterilization. The differences in the mean values were contrasted and compared with the control group and analyzed using two-way analysis of variance (P < 0.05). RESULTS: The results showed that chemical disinfection and autoclave sterilization had no significant effect on the tensile strength and surface roughness, whereas microwave sterilization showed a statistically-significant reduction in tensile strength, and an increase in surface roughness. None of the disinfection and sterilization techniques had a significant effect on wettability. However, autoclave and microwave sterilization resulted in an increase in hydrophilicity of all the materials tested. CONCLUSION: Chemical disinfection and autoclave sterilization had no statistically-significant effect on the tested properties of elastomers, thus autoclave sterilization can be considered as an alternative and an effective mode of disinfection and sterilization to eliminate all forms of disease causing microorganisms from dental impressions.


Assuntos
Materiais para Moldagem Odontológica/química , Desinfecção , Elastômeros/química , Esterilização , Resistência à Tração , Molhabilidade , Teste de Materiais , Propriedades de Superfície
8.
Dent Mater ; 33(1): 71-83, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27842886

RESUMO

OBJECTIVE: The regeneration of periodontal tissues lost as a consequence of destructive periodontal disease remains a challenge for clinicians. Guided tissue regeneration (GTR) has emerged as the most widely practiced regenerative procedure. Aim of this study was to electrospin chitosan (CH) membranes with a low or high degree of fiber orientation and examines their suitability for use as a surface layer in GTR membranes, which can ease integration with the periodontal tissue by controlling the direction of cell growth. METHODS: A solution of CH-doped with polyethylene oxide (PEO) (ratio 95:5) was prepared for electrospinning. Characterization was performed for biophysiochemical and mechanical properties by means of scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, swelling ratio, tensile testing and monitoring degradation using pH analysis, weight profile, ultraviolet-visible (UV-vis) spectroscopy and FTIR analysis. Obtained fibers were also assessed for viability and matrix deposition using human osteosarcoma (MG63) and human embryonic stem cell-derived mesenchymal progenitor (hES-MP) cells. RESULTS: Random and aligned CH fibers were obtained. FTIR analysis showed neat CH spectral profile before and after electrospinning. Electropsun mats were conducive to cellular attachment and viability increased with time. The fibers supported matrix deposition by hES-MPs. Histological sections showed cellular infiltration as well. SIGNIFICANCE: The surface layer would act as seal to prevent junctional epithelium from falling into the defect site and hence maintain space for bone regeneration.


Assuntos
Regeneração Óssea , Quitosana , Regeneração Tecidual Guiada , Periodonto , Regeneração Tecidual Guiada Periodontal , Humanos , Masculino , Membranas Artificiais
9.
Medicina (Kaunas) ; 52(5): 263-268, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27717563

RESUMO

BACKGROUND AND OBJECTIVE: The exact etiology of recurrent aphthous ulcers (RAS) is unknown. The management of RAS is not always straightforward. The aim of this review is to critically analyze and summarize the clinical literature focusing on the management of aphthous ulcers using low-level lasers. MATERIALS AND METHODS: The Medline (PubMed), Web of Knowledge (ISI), Cochrane Central Register of Controlled Trials (CENTRAL) and Embase databases were searched electronically for studies published in last 20 years (1995-2015) using the keywords "recurrent aphthous stomatitis," "aphthous ulcers," and "laser." RESULTS: A total of 85 articles were found during the initial search; 76 studies were excluded for not fulfilling the criteria whereas nine studies were deemed suitable for this review. Among the included studies, two articles were case reports and seven were randomized clinical trials. Study design, sample size, type of intervention and control of each study were critically analyzed and summarized according to the CONSORT protocol. In majority of the patients, immediate pain relief and accelerated ulcer healing was observed following irradiation with lasers. CONCLUSIONS: Although various types of lasers have succeeded in providing immediate pain relief to patients, carbon dioxide (CO2) lasers have the unique advantage of requiring a short exposure time (5-10s). In order to ascertain the efficacy of laser for treating ulcers in the clinical setting, more clinical trials are required.


Assuntos
Dor Crônica/radioterapia , Lasers de Gás/uso terapêutico , Terapia com Luz de Baixa Intensidade , Estomatite Aftosa/radioterapia , Adulto , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
10.
J Mech Behav Biomed Mater ; 61: 617-626, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27068802

RESUMO

In this manuscript for the first time calcium hydroxide (Ca(OH)2) has been used for preparation of bioactive glass (BG-2) by co-precipitation method and compared with glass prepared using calcium nitrate tetrahydrate Ca(NO3)2·4H2O (BG-1), which is a conventional source of calcium. The new source positively affected physical, biological and mechanical properties of BG-2. The glasses were characterized by Fourier transform infrared (FTIR), X-Ray Diffractometer (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis/Differential Scanning Calorimetry (TGA-DSC), BET surface area analysis and Knoop hardness. The results showed that BG-2 possessed relatively larger surface properties (100m(2)g(-1) surface area) as compared to BG-1 (78m(2)g(-1)), spherical morphology and crystalline phases (wollastonite and apatite) after sintering at lower than conventional temperature. These properties contribute critical role in both mechanical and biological properties of glasses. The Knoop hardness measurements revealed that BG-2 possessed much better hardness (0.43±0.06GPa at 680°C and 2.16±0.46GPa at 980°C) than BG-1 (0.24±0.01 at 680°C and 0.57±0.07GPA at 980°C) under same conditions. Alamar blue Assay and confocal microscopy revealed that BG-2 exhibited better attachment and proliferation of MG63 cells. Based on the improved biological properties of BG-2 as a consequent of novel calcium source selection, BG-2 is proposed as a bioactive ceramic for hard tissue repair and regeneration applications.


Assuntos
Materiais Biocompatíveis , Hidróxido de Cálcio/química , Vidro/química , Cerâmica , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
11.
Technol Health Care ; 24(2): 153-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26484886

RESUMO

BACKGROUND: Bleaching agents are commonly used in dentistry for treating the discolored teeth. A number of biomaterials and methods are in clinical applications. OBJECTIVE: The major aim of this study was to evaluate the effects of two different bleaching agents on the surface roughness properties of dental resin nanocomposites and dental porcelains using various regimes. METHODS: This study was conducted using direct restorative hybrid and nanocomposite materials and dental porcelains. The specimens were treated using the bleaching gels [(Opalescence Boost 40% OP) and (Whiteness HP 35% WHP)] for 30, 45, 60 and 120 minutes respectively. Treated samples were analyzed for surface roughness properties using contact mode surface profilometry and surface topography using scanning electron microscopy (SEM). Data was analyzed statistically using analysis of variance (ANOVA). RESULTS: There were no significant changes observed in the roughness of nanofill, nanohybrid composites and ceramic materials compared to microhybrid resin composites (p> 0.05). The SEM photomicrographs confirmed the results of the profilometer showing slight changes in the microhybrid resin composite. CONCLUSIONS: No remarkable difference was observed between the bleaching agents (Opalescence Boost and Whiteness HP Blue) for the surface roughness of tested dental materials. The bleaching agents can be used without harming the ceramic, nanofilled or nanohybrid resin restorations. However, if microhybrid or microfilled composite restorations are present in the oral cavity, bleaching may damage the surface finish and requiring replacement of restorations.


Assuntos
Resinas Compostas/química , Porcelana Dentária/química , Propriedades de Superfície/efeitos dos fármacos , Clareadores Dentários/farmacologia , Materiais Biocompatíveis , Humanos , Teste de Materiais , Nanocompostos
12.
Acta Biomater ; 23: 317-328, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25968357

RESUMO

Guided tissue regeneration (GTR) membranes have been used for the management of destructive forms of periodontal disease as a means of aiding regeneration of lost supporting tissues, including the alveolar bone, cementum, gingiva and periodontal ligaments (PDL). Currently available GTR membranes are either non-biodegradable, requiring a second surgery for removal, or biodegradable. The mechanical and biofunctional limitations of currently available membranes result in a limited and unpredictable treatment outcome in terms of periodontal tissue regeneration. In this study, porous membranes of chitosan (CH) were fabricated with or without hydroxyapatite (HA) using the simple technique of freeze gelation (FG) via two different solvents systems, acetic acid (ACa) or ascorbic acid (ASa). The aim was to prepare porous membranes to be used for GTR to improve periodontal regeneration. FG membranes were characterized for ultra-structural morphology, physiochemical properties, water uptake, degradation, mechanical properties, and biocompatibility with mature and progenitor osteogenic cells. Fourier transform infrared (FTIR) spectroscopy confirmed the presence of hydroxyapatite and its interaction with chitosan. µCT analysis showed membranes had 85-77% porosity. Mechanical properties and degradation rate were affected by solvent type and the presence of hydroxyapatite. Culture of human osteosarcoma cells (MG63) and human embryonic stem cell-derived mesenchymal progenitors (hES-MPs) showed that all membranes supported cell proliferation and long term matrix deposition was supported by HA incorporated membranes. These CH and HA composite membranes show their potential use for GTR applications in periodontal lesions and in addition FG membranes could be further tuned to achieve characteristics desirable of a GTR membrane for periodontal regeneration.


Assuntos
Géis/química , Regeneração Tecidual Guiada Periodontal/instrumentação , Membranas Artificiais , Osteoblastos/citologia , Células-Tronco/citologia , Alicerces Teciduais , Proliferação de Células/fisiologia , Células Cultivadas , Quitosana/química , Durapatita/química , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Congelamento , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Teste de Materiais , Osteoblastos/fisiologia , Osteogênese/fisiologia , Porosidade , Células-Tronco/fisiologia , Estresse Mecânico , Resistência à Tração
13.
Materials (Basel) ; 8(2): 717-731, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28787967

RESUMO

Rationalizing has become a new trend in the world of science and technology. Nanotechnology has ascended to become one of the most favorable technologies, and one which will change the application of materials in different fields. The quality of dental biomaterials has been improved by the emergence of nanotechnology. This technology manufactures materials with much better properties or by improving the properties of existing materials. The science of nanotechnology has become the most popular area of research, currently covering a broad range of applications in dentistry. This review describes the basic concept of nanomaterials, recent innovations in nanomaterials and their applications in restorative dentistry. Advances in nanotechnologies are paving the future of dentistry, and there are a plenty of hopes placed on nanomaterials in terms of improving the health care of dental patients.

14.
Acta Odontol Scand ; 69(6): 367-73, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21449690

RESUMO

OBJECTIVE: To investigate the failure of 15 dental implants (Paragon/Zimmer) in relation to their surface quality. MATERIALS AND METHODS: The study comprised of 15 dental implants (7 mm D Advent Implant, 3.9 mm D apex design implant), which were followed from surgery to completion of prosthetic restorations. The implants were placed during a 6-year period from 2003-2009 in non-smoking patients (male; 7, females; 5). There were eight upper and seven lower implants. Surface characterization after immersion in SBF of these failed implants was investigated using SEM and EDS compared to that of an unused implant of the same brand. RESULTS: Results revealed that, following immersion in SBF, the implant surfaces showed new components like Ca(+), Na(+) and Cl(-), but in trace quantities. CONCLUSIONS: After SEM observation and EDS analysis, it was concluded that the apatite layer formation could not be verified.


Assuntos
Implantes Dentários , Materiais Dentários/química , Falha de Restauração Dentária , Titânio/química , Adulto , Apatitas/análise , Cálcio/análise , Cloretos/análise , Feminino , Humanos , Imersão , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Plasma , Porosidade , Potássio/análise , Sódio/análise , Espectrometria por Raios X , Propriedades de Superfície , Temperatura , Fatores de Tempo , Titânio/análise
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