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1.
Braz Oral Res ; 34: e005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022224

RESUMO

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Assuntos
Apatitas/efeitos da radiação , Bis-Fenol A-Glicidil Metacrilato/efeitos da radiação , Resinas Compostas/efeitos da radiação , Fluoretos/química , Cimentos de Ionômeros de Vidro/efeitos da radiação , Radiação Ionizante , Zircônio/efeitos da radiação , Análise de Variância , Apatitas/química , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Resistência à Flexão , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Espectrometria por Raios X , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo , Zircônio/química
2.
Microsc Res Tech ; 82(11): 1869-1877, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31373738

RESUMO

Laser irradiation has been proposed as a preventive method against dental caries since it is capable to inhibit enamel demineralization by reducing carbonate and modifying organic matter, yet it can produce significant morphological changes. The purpose of this study was to evaluate the influence of Er:YAG laser irradiation on superficial roughness of deciduous dental enamel and bacterial adhesion. Fifty-four samples of deciduous enamel were divided into three groups (n = 18 each). G1_control (nonirradiated); G2_100 (7.5 J/cm2 ) and G3_100 (12.7 J/cm2 ) were irradiated with Er:YAG laser at 7.5 and 12.7 J/cm2 , respectively, under water irrigation. Surface roughness was measured before and after irradiation using a profilometer. Afterwards, six samples per group were used to measure bacterial growth by XTT cell viability assay. Adhered bacteria were observed using confocal laser scanning microscopy (CLSM) and a scanning electron microscopy (SEM). Paired t-, one-way analysis of variance (ANOVA), Kruskal-Wallis and pairwise Mann-Whitney U tests were performed to analyze statistical differences (p < .05). Before treatment, samples showed homogenous surface roughness, and after Er:YAG laser irradiation, the surfaces showed a significant increase in roughness values (p < .05). G3_100 (12.7 J/cm2 ) showed the highest amount of Streptococcus mutans adhered (p < .05). The increase in the roughness of the tooth enamel surfaces was proportional to the energy density used; the increase in surface roughness caused by laser irradiation did not augment the adhesion of Streptococcus sanguinis; only the use of the energy density of 12.7 J/cm2 favored significantly the adhesion of S. mutans.


Assuntos
Aderência Bacteriana/efeitos da radiação , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Streptococcus mutans/fisiologia , Streptococcus/fisiologia , Aderência Bacteriana/fisiologia , Humanos , Microscopia Eletrônica de Varredura , Streptococcus/crescimento & desenvolvimento , Streptococcus/efeitos da radiação , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
3.
PLoS One ; 14(7): e0219198, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291308

RESUMO

The light-promoted recovery of epidermal barrier of skin was evaluated by the associated recovery of transepidermal potential (TEP), the potential difference between the surface and dermis of skin, by using porcine skin samples. An accelerated recovery of TEP was observed by irradiation of red light with the irradiance of 40 mW/cm2 and a duration of > 10 min. The influence of the light stimulation to the surroundings (~ 20 mm) was also observed. The irradiations of blue and purple lights were ineffective in accelerating the barrier recovery. These characteristics of the light stimulation would be useful for the design of effective and safe phototherapy devices for skin. The present study proves that the TEP can serve as a spatiotemporal indicator of the epidermal barrier function.


Assuntos
Derme/efeitos da radiação , Epiderme/efeitos da radiação , Fototerapia , Pele/efeitos da radiação , Acetona/metabolismo , Animais , Humanos , Luz , Sais/metabolismo , Propriedades de Superfície/efeitos da radiação , Suínos
4.
Int J Mol Sci ; 20(8)2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31003413

RESUMO

Gamma-ray radiation was used as a clean and easy method for turning the physicochemical properties of graphene oxide (GO) in this study. Silane functionalized-GO were synthesized by chemically grafting 3-aminopropyltriethoxysilane (APTES) and 3-glycidyloxypropyltrimethoxysilane (GPTES) onto GO surface using gamma-ray irradiation. This established non-contact process is used to create a reductive medium which is deemed simpler, purer and less harmful compared conventional chemical reduction. The resulting functionalized-GO were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA), and Raman spectroscopy. The chemical interaction of silane with the GO surface was confirmed by FT-IR. X-ray diffraction reveals the change in the crystalline phases was due to surface functionalization. Surface defects of the GO due to the introduction of silane mioties was revealed by Raman spectroscopy. Thermogravimetric analysis of the functionalized-GO exhibits a multiple peaks in the temperature range of 200-650 °C which corresponds to the degradation of chemically grafted silane on the GO surface.


Assuntos
Grafite/química , Compostos de Organossilício/química , Propilaminas/química , Silanos/química , Compostos de Epóxi/síntese química , Compostos de Epóxi/química , Compostos de Epóxi/efeitos da radiação , Raios gama , Grafite/síntese química , Grafite/efeitos da radiação , Microscopia Eletrônica de Varredura , Compostos de Organossilício/efeitos da radiação , Propilaminas/síntese química , Propilaminas/efeitos da radiação , Silanos/síntese química , Silanos/efeitos da radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Propriedades de Superfície/efeitos da radiação , Temperatura Ambiente , Termogravimetria , Difração de Raios X
5.
J Appl Oral Sci ; 27: e20180075, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30624462

RESUMO

Currently, there is no consensus in terms of defining the minimum radiant exposure values necessary for achieving adequate properties of composite resin. In addition, the long-term influence that radiant exposure has on the properties of composite resins is still questionable. OBJECTIVE: The objective of this study was to evaluate the effect of radiant exposure and UV accelerated aging on the physico-chemical and mechanical properties of micro-hybrid and nanofilled composite resins. MATERIAL AND METHODS: A nanofilled (Filtek Supreme; 3M ESPE) and a micro-hybrid composite resin (Filtek Z250; 3M ESPE) were investigated under different radiant exposures (3.75, 9, and 24 J/cm2) and UV accelerated aging protocols (0, 500, 1000, and 1500 aging hours). The degree of conversion (DC), flexural strength (FS), modulus (M), water sorption (WS), and solubility (WL) were evaluated. The results obtained were analyzed using two-way ANOVA and Tukey's test. Comparisons were performed using a significance level of α=0.05. RESULTS: The DC, FS, and M were found to be significantly influenced by both radiant exposure and accelerated aging time. The DC and EM increased with radiant exposure in the no-aging group (0-hour aging) for both micro-hybrid and nanofilled composites, whereas no correlation was found after accelerated aging protocols. WS and WL of micro-hybrid and nanofilled composite resins were scarcely affected by radiant exposure (p>0.05), whereas they were significantly reduced by accelerated aging (p<0.001). CONCLUSIONS: Although increasing radiant exposure affected the degree of conversion and mechanical properties of micro-hybrid and nanofilled composites, no influence on the hydrolytic degradation of the material was observed. In contrast, UV accelerated aging affected both the physico-chemical and mechanical properties of the composites.


Assuntos
Resinas Compostas/química , Resinas Compostas/efeitos da radiação , Raios Ultravioleta , Análise de Variância , Luzes de Cura Dentária , Resistência à Flexão/efeitos da radiação , Teste de Materiais , Microscopia Eletrônica de Varredura , Transição de Fase/efeitos da radiação , Processos Fotoquímicos/efeitos da radiação , Polimerização/efeitos da radiação , Doses de Radiação , Valores de Referência , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo , Água/química
6.
Arch Oral Biol ; 98: 195-203, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30502562

RESUMO

OBJECTIVE: To investigate effects of HIFU on macrophage phenotype, surface micro-topography and nano-scale surface mechanical properties of dental cementum. MATERIALS AND METHODS: Root discs (2 mm thickness) were cut apical to CEJ and sectioned into quadrants. HIFU setup with bowl-shaped piezo ceramic transducer submerged in a water tank was used for exposure on each specimen for 15 s, 30 s or 60 s. The specimens of the control group were left without any HIFU exposure. HIFU was generated with a continuous sinusoidal wave of 120Vpp amplitude, 250 KHZ resonance-frequency and highest ultrasonic pressure of ∼10 bar at the focus. Specimens for SEM were viewed, and micro-topography characterization performed, using AFM and Ra parameter and surface area (SA) calculated by specialized SPM surface analysis software. For nano-indentation testing, experiments were carried out using AFM. Macrophage cell isolation and culturing was performed on cementum to receive the HIFU treatment at different time periods. Raman spectroscopy were scanned to create spectra perpendicular to the cementum substrate to analyze generation of standard spectra for Raman intensity ratio of hydroxyapatite normalized to the peaks ν1 960 cm-1. Data was expressed as means ± standard deviations and analyzed by one-way ANOVA in term of Ra, SA, H and Er. Different points for fluorescence intensity ratio were analyzed by Raman using Wilcoxon rank sum test. RESULTS: HIFU exposure at 60 s removed the smear layer and most of cementum appeared smoothened. AFM characterisation, showed a slight decrease in the irregularity of the surface as exposure time increased. Intact macrophages can be identified in control and all experimental HIFU groups. The level of fluorescence for the control and HIFU 15 and 30 s were low as compared to HIFU 60 s. CONCLUSION: If HIFU can be successfully implemented, it may be a possible alternative to current methods used in periodontal therapy to achieve smooth root surfaces.


Assuntos
Cemento Dentário/metabolismo , Cemento Dentário/efeitos da radiação , Tratamento por Ondas de Choque Extracorpóreas/métodos , Macrófagos/metabolismo , Macrófagos/efeitos da radiação , Análise de Variância , Cemento Dentário/ultraestrutura , Relação Dose-Resposta à Radiação , Durapatita , Fluorescência , Doenças Periodontais/radioterapia , Doses de Radiação , Análise Espectral Raman , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo , Raiz Dentária/efeitos da radiação , Raiz Dentária/ultraestrutura , Transdutores
7.
Braz Oral Res ; 32: e122, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30569972

RESUMO

The effects of tooth brushing could affect the long-term esthetic outcome of composite restorations. This study evaluated the effect of two different emission spectrum light-curing units on the surface roughness, roughness profile, topography and microhardness of bulk-fill composites after in vitro toothbrushing. Valo (multiple-peak) and Demi Ultra (single-peak) curing lights were each used for 10s to polymerize three bulk-fill resin composites: Filtek Bulk Fill Posterior Restorative (FBF), Tetric EvoCeram Bulk Fill (TET) and Surefil SDR Flow (SDR). After 30,000 reciprocal strokes in a toothbrushing machine, the roughness profile, surface roughness, surface morphology, and microhardness were examined. Representative SEM images were also obtained. When light-cured with the Demi Ultra, SDR showed the most loss in volume compared to the other composites and higher volume loss compared to when was light-cured with Valo. The highest surface roughness and roughness profile values were found in SDR after toothbrushing, for both light-curing units tested. FBF always had the greatest microhardness values. Light-curing TET with Valo resulted in higher microhardness compared to when using the Demi Ultra. Confocal and SEM images show that toothbrushing resulted in smoother surfaces for FBF and TET. All composites exhibited surface volume loss after toothbrushing. The loss in volume of SDR depended on the light-curing unit used. Toothbrushing can alter the surface roughness and superficial aspect of some bulk-fill composites. The choice of light-curing unit did not affect the roughness profile, but, depending on the composite, it affected the microhardness.


Assuntos
Resinas Compostas/efeitos da radiação , Luzes de Cura Dentária , Escovação Dentária/efeitos adversos , Análise de Variância , Resinas Compostas/química , Dureza/efeitos dos fármacos , Dureza/efeitos da radiação , Cura Luminosa de Adesivos Dentários/métodos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Polimerização , Reprodutibilidade dos Testes , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo
8.
Braz Oral Res ; 32: e121, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30517430

RESUMO

The aim of this study was to evaluate the influence of radiation therapy on root canal sealer push-out bond strength (BS) to dentin and the sealer/dentin interface after different final irrigation solutions (NaOCl, EDTA, and chitosan). Sixty-four maxillary canines were distributed into two groups (n=30): non-irradiated and irradiated with 60 Gy. Canals were prepared with Reciproc-R50 and subdivided (n=10) for final irrigation (NaOCl, EDTA, chitosan) and filled. Three dentin slices were obtained from each root third. The first slice of each third was selected for BS evaluation, and the failure mode was determined by stereomicroscopy. SEM analysis of the sealer-dentin interface was performed in the remaining slices. Two-way ANOVA and Tukey's tests (α=0.05) were used. Lower BS (P<0.0001) was obtained after irradiation (2.07±0.79 MPa), regardless of the final irrigation solution used. The NaOCl group (P<0.001) had the lowest BS in the irradiated (1.68±0.72) and non-irradiated (2.39±0.89) groups, whereas the EDTA (irradiated: 2.14±0.77 and non-irradiated: 3.92±1.54) and chitosan (irradiated: 2.37±0.73 and non-irradiated: 3.51±1.47) groups demonstrated a higher BS (P<0.05). The highest values were observed in the coronal third (3.17±1.38) when compared to the middle (2.74±1.36) and apical ones (2.09±0.97)(P<0.0001). There were more cohesive failures and more gaps in irradiated specimens, regardless of the final solution. The present study showed that radiation was associated with a decrease in BS, regardless of the final solution used, whereas chitosan increased BS in teeth subjected to radiation therapy.


Assuntos
Colagem Dentária/métodos , Dentina/efeitos dos fármacos , Dentina/efeitos da radiação , Resinas Epóxi/efeitos da radiação , Materiais Restauradores do Canal Radicular/efeitos da radiação , Irrigantes do Canal Radicular/efeitos da radiação , Análise de Variância , Quitosana/química , Falha de Restauração Dentária , Ácido Edético/química , Resinas Epóxi/química , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação , Raiz Dentária/efeitos dos fármacos , Raiz Dentária/efeitos da radiação
9.
J Appl Oral Sci ; 27: e20180126, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30540073

RESUMO

OBJECTIVES: The aim of this in vitro study was to evaluate the bonding strength of non-simplified dentin bonding systems (DBS) to dentin irradiated with a diode laser (970 nm) immediately and after 12 months of water storage following either primer or bond application. MATERIAL AND METHODS: The experimental design included three different factors: DBS type [AdperTM Scotchbond Multipurpose (MP) and Clearfil™ SE Bond (CSE)], irradiation [without irradiation - control (C), irradiation after primer application (AP), and irradiation after bond application (AB)], and time [initial (I) and after 12 months of water storage (12 m)]. Sixty sound human third molars (n = 10) were obtained, and their flat occlusal dentin areas were prepared and standardized. Laser irradiation was performed in the contact mode perpendicular to the dental surface over an automatically selected scanning area at a pulse energy of 0.8 W, frequency of 10 Hz, and energy density of 66.67 J/cm2. After 7 days of treatment, the specimens were cut, and half of them were subjected to microtensile testing (500 N/0.05 mm/min), whereas the remaining sticks were examined after 12 months of water storage. The obtained data were analyzed by three-way analysis of variance (ANOVA) followed by a Tukey test (p<0.05). The observed fracture modes were investigated using a portable digital microscope with a magnification of 40x. RESULTS: Among the utilized DBS, MP generally exhibited higher bond strengths, but did not always differ from CSE under similar conditions. The irradiation factor was statistically significant only for the MP/AB groups. After 12 months of storage, all groups demonstrated a significant reduction in the bond strength, whereas the results of fracture analysis showed a predominance of the adhesive type. CONCLUSIONS: The laser treatment of non-simplified DBS was not able to stabilize their bonding characteristics after 12 months.


Assuntos
Colagem Dentária/métodos , Adesivos Dentinários/efeitos da radiação , Dentina/efeitos da radiação , Lasers Semicondutores , Cimentos de Resina/efeitos da radiação , Análise de Variância , Dentina/efeitos dos fármacos , Adesivos Dentinários/química , Humanos , Teste de Materiais , Microscopia de Força Atômica , Polimerização/efeitos da radiação , Valores de Referência , Reprodutibilidade dos Testes , Cimentos de Resina/química , Propriedades de Superfície/efeitos da radiação , Resistência à Tração , Fatores de Tempo , Água/química
10.
Microsc Res Tech ; 81(9): 973-979, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30295342

RESUMO

The aim of this study was to evaluate the chemical and morphological effects of different lasers as a final surface treatment for endodontic therapy through energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) respectively. Twenty-five maxillary canines were selected and instrumented with K3 system. Roots were randomly distributed into five groups (n = 5) according to the surface treatment: GI (distilled water), GII (NaOCl + EDTA), GIII (NaOCl + EDTA + 980 nm diode laser), GIV (NaOCl + EDTA+ 1,064 nm Nd:YAG laser), and GV (NaOCl + EDTA+ 2,780 nm Er, Cr:YSGG laser). Lasers were applied for 20 s and samples were bisected, exposing the treated surface and then subjected to elements quantification by EDS and morphological evaluation by scanning electron microscope (SEM). EDS data were submitted to ANOVA-two way, and SEM scores were submitted to two-way Kruskal-Wallis and Dunn's tests. The EDS analysis showed no difference for the chemical elements and Ca/P ratio between groups (p > .05). Statistical analysis showed more intense results for GV and less intense results for GI (p < .05). The GIII showed an amorphous organic matrix surface, while GV provided greater removal of intertubular dentin forming craters, and GIV promoted dentin fusion. The EDS method used in this study was not able to verify any chemical changes in root canal dentin; Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser were capable of modifying the dentin morphology, correlating characteristics features for each one, which are essential clinical knowledge to establish the correct indication for each case. RESEARCH HIGHLIGHTS: EDS was not able to verify any chemical changes in root canal dentin after 980 nm diode, Nd:YAG and Er;Cr:YSGG laser treatments Nd:YAG, Er, Cr:YSGG, and 980 nm diode laser modified dentin morphology, correlating characteristics features for each one.


Assuntos
Dente Canino/efeitos da radiação , Dentina/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Raiz Dentária/efeitos da radiação , Dente não Vital , Dente Canino/anatomia & histologia , Dente Canino/química , Dentina/anatomia & histologia , Dentina/química , Humanos , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Propriedades de Superfície/efeitos da radiação , Raiz Dentária/anatomia & histologia , Raiz Dentária/química
11.
Braz Oral Res ; 32: e47, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30281682

RESUMO

The objective of this study was to assess the effect of a UV light-based auxiliary illumination on adhesive remnant (AR) removal after orthodontic debonding. Sixty human molars were divided according to the adhesive used for bonding: O-opaque; LF-low fluorescence; and HF-high fluorescence. After debonding, the teeth were subdivided according to the AR removal method: No UV light or With UV light. After AR removal, the teeth were polished. Direct visual analysis, scanning electron microscopy (SEM) and time quantification for AR removal analyses were performed (Fisher-Freeman-Halton, Fisher's exact, chi-square trend, ANOVA, and independent t-tests; α = 5%). Concerning the adhesives, there was no significant difference among direct visual, SEM and time analyses for AR removal (p ≥ 0.05). Regarding AR removal methods, a similarity among the subgroups was verified for direct visual and SEM analyses (p≥0.05). However, a significant trend was verified for the with UV light method to produce greater marks, and the no UV light method, to produce a greater rate of samples with AR before polishing (p = 0.015). AR removal with light was significantly quicker in comparison with the no UV light method (p < 0.0001). The use of UV light may aid orthodontists in removing AR more thoroughly and in less time. However, they should receive special training to apply this technology, and should never dismiss the final polishing procedure.


Assuntos
Cimentos Dentários/efeitos da radiação , Descolagem Dentária/métodos , Esmalte Dentário/efeitos da radiação , Aparelhos Ortodônticos , Raios Ultravioleta , Análise de Variância , Cimentos Dentários/química , Polimento Dentário/métodos , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo
12.
Clin Implant Dent Relat Res ; 20(4): 583-591, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29939477

RESUMO

BACKGROUND: Studies have reported a high prevalence of peri-implantitis. The etiology of peri-implantitis remains unclear and no available treatments result in total resolution of established peri-implantitis. PURPOSE: To investigate the factors that interfere with osteoblast adhesion to contaminated titanium surfaces after different surface treatments. MATERIALS AND METHODS: Grade 4 titanium discs were randomly divided into 5 groups and each group was divided into 2 subgroups, with one contaminated with Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), and the other contaminated with Porphyromonas gingivalis (P. gingivalis). Group 1 did not receive bacterial inoculation or surface debridement and served as a control. Group 2 received A. actinomycetemcomitans or P. gingivalis inoculation, separately. Group 3 received bacterial inoculation and titanium curette debridement, followed by normal saline irrigation. Group 4 received bacterial inoculation, curette debridement, normal saline irrigation, and ultrasonication. Group 5 received bacterial inoculation, curette debridement, normal saline irrigation, and placement in 0.12% chlorhexidine. After various surface treatments, the surface roughness and hydrophilicity of the titanium surface were measured, the number of adhered osteoblast cells was calculated, and the amount of residual lipopolysaccharide (LPS) was quantified. RESULTS: A. actinomycetemcomitans and P. gingivalis biofilms noticeably reduced surface hydrophilicity. Groups 3-5 showed decreased hydrophilicity and fewer adhered osteoblast cells compared with the control group. Although ultrasonication was more effective in removing LPS than curette debridement and chlorhexidine, cell adhesion was not as high as with clean titanium discs. CONCLUSIONS: The non-surgical treatment used in this study was not effective in removing LPS from titanium surfaces and increasing osteoblast adhesion. A more effective method to remove LPS completely is required to enhance the treatment outcome of peri-implantitis.


Assuntos
Adesão Celular , Contaminação de Equipamentos , Osteoblastos , Titânio/química , Aggregatibacter actinomycetemcomitans , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Clorexidina/farmacologia , Desbridamento , Implantes Dentários/microbiologia , Interações Hidrofóbicas e Hidrofílicas , Lipopolissacarídeos/efeitos da radiação , Teste de Materiais , Peri-Implantite/etiologia , Porphyromonas gingivalis , Solução Salina/farmacologia , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação , Ultrassom/métodos
13.
J Appl Oral Sci ; 26: e20170029, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29742259

RESUMO

Literature has reported positive results regarding the use of lasers in the control of erosive lesions; however, evaluating whether they are effective in the control of the progression of erosive/abrasive lesions is important. Objectives This study aimed to evaluate the effect of the Er:YAG laser irradiation in controlling the progression of erosion associated with abrasive lesions in enamel. Material and methods Bovine incisors were sectioned, flattened and polished. Forty-eight enamel slabs were subjected to treatment in an intraoral phase. Twelve volunteers used an intraoral appliance containing one slab that was irradiated with an Er:YAG laser (5.2 J/cm2, 85 mJ, 2 Hz) and another non-irradiated slab on each side of the appliance, during one phase of 5 d, under a split-mouth design. Devices were subjected to erosive challenges (1% citric acid, 5 min, 3 times a day) and abrasive challenges one h after (brushing force of 1.5 N for 15 s) randomly and independently on each side of the device. Measurements of enamel loss were performed via 3D optical profilometry (µm). We analyzed data using the Kruskal-Wallis and Mann-Whitney tests and morphological characteristics via scanning electron microscopy. Results Following erosive and abrasive challenges, the group that was irradiated with the Er:YAG laser presented less loss of structure than the non-irradiated group. The group that underwent erosion and irradiation did not exhibit a significant difference from the non-irradiated group. Conclusion Irradiation with the Er:YAG laser did not control the loss of structure of enamel subjected to erosion but did control abrasion after erosion.


Assuntos
Esmalte Dentário/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Abrasão Dentária/prevenção & controle , Erosão Dentária/prevenção & controle , Animais , Bovinos , Ácido Cítrico/química , Esmalte Dentário/efeitos dos fármacos , Progressão da Doença , Testes de Dureza , Imagem Tridimensional , Teste de Materiais , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos da radiação
14.
J Mater Sci Mater Med ; 29(5): 56, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728865

RESUMO

The purpose of this study was to evaluate blood and platelet response to nanostructured TiO2 coatings and to investigate the effect of Ultraviolet (UV) light treatment on blood clotting ability, platelet activation and protein adhesion. Ti-6Al-4V titanium alloy plates (n = 138) were divided into three groups; a sol-gel derived MetAliveTM coating (MA); hydrothermal coating (HT); and a non-coated group (NC). Sixty nine titanium substrates were further treated with UV light for 1 h. The thrombogenicity of the titanium substrates was assessed using fresh human blood with a whole blood kinetic clotting time method. The platelet adhesion test was conducted to evaluate the morphology and adhesion behavior of the platelets on the titanium substrates. Human diluted plasma and bovine fibronectin were used to evaluate protein adsorption. Total clotting time for the UV treated HT, MA and NC titanium substrates was almost 40 min compared to 60 min for non-UV substrates, the total clotting time for the UV treated groups were significantly lower than that of the non UV NC group (p < 0.05). UV light treatment had significantly enhanced coagulation rates. The HT and MA substrates presented more platelet aggregation, spreading and pseudopod formation in comparison with the NC substrates. UV treatment did not affect the platelet activation and protein adsorption. This in vitro study concluded that nanostructured titanium dioxide implant surfaces obtained by sol-gel and hydrothermal coating methods increased coagulation rates and enhanced platelet response when compared with non-coated surfaces. UV light treatment clearly improved thrombogenicity of all examined Ti-6Al-4V surfaces.


Assuntos
Plaquetas/citologia , Plaquetas/fisiologia , Materiais Revestidos Biocompatíveis/efeitos da radiação , Tecidos Suporte/química , Titânio/química , Raios Ultravioleta , Adulto , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Adesão Celular/fisiologia , Materiais Revestidos Biocompatíveis/química , Feminino , Voluntários Saudáveis , Humanos , Teste de Materiais , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Agregação Plaquetária/fisiologia , Próteses e Implantes , Propriedades de Superfície/efeitos da radiação
15.
An Acad Bras Cienc ; 90(1): 195-204, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29641759

RESUMO

Demand for medical implants is rising day by day as the world becomes the place for more diseased and older people. Accordingly, in this research, metallocene polyethylene (mPE), a commonly used polymer was treated with UV rays for improving its biocompatibility. Scanning electron microscopy (SEM) images confirmed the formation of crests and troughs, which depicts the improvement of surface roughness of mPE substrates caused by UV etching. Accordingly, the contact angle measurements revealed that the wettability of mPE-2.5 J/cm2 (68.09º) and mPE-5 J/cm2 (57.93º) samples were found to be increased compared to untreated mPE (86.84º) indicating better hydrophilicity. Further, the UV treated surface exhibited enhanced blood compatibility as determined in APTT (untreated mPE- 55.3 ± 2.5 s, mPE-2.5 J/cm2 - 76.7 ± 4.1 s and mPE-5 J/cm2 - 112.3 ± 2 s) and PT (untreated mPE - 24.7 ± 1.5 s, mPE- 2.5 J/cm2 - 34.3 ± 1.1 s and mPE-5 J/cm2 - 43 ± 2 s) assay. Moreover, the treated mPE-2.5 J/cm2 (4.88%) and mPE-5 J/cm2 (1.79%) showed decreased hemolytic percentage compared to untreated mPE (15.40%) indicating better safety to red blood cells. Interestingly, the changes in physicochemical properties of mPE are directly proportional to the dosage of the UV rays. UV modified mPE surfaces were found to be more compatible as identified through MTT assay, photomicrograph and SEM images of the seeded 3T3 cell population. Hence UV-modified surface of mPE may be successfully exploited for medical implants.


Assuntos
Teste de Materiais , Metalocenos/efeitos da radiação , Raios Ultravioleta , Células 3T3 , Animais , Bovinos , Hemólise , Histocompatibilidade , Interações Hidrofóbicas e Hidrofílicas , Metalocenos/química , Camundongos , Microscopia Eletrônica de Varredura , Coelhos , Propriedades de Superfície/efeitos da radiação
16.
J Dent ; 72: 29-38, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29501794

RESUMO

OBJECTIVES: To evaluate the effects of airborne-particle abrasion (APA) and Er,Cr:YSGG laser irradiation on 4-point-flexural strength, phase transformation and morphologic changes of zirconia ceramics treated at pre-sintered or post-sintered stage. METHODS: Three hundred and forty-two bar shaped zirconia specimens were milled with different sizes according to the flexural strength test (n = 10), X-ray diffraction (XRD) (n = 4) and field emission scanning electron microscope (FE-SEM) (n = 4) analyses. For each test protocol, specimens were divided into 4 main groups whether the surface treatments applied before or after sintering and whether the specimens received heat treatment or not as pre-sintered, post-sintered no-heat and post-sintered heat-treated groups, and a group was served as control. Main groups were further divided into 6 equal subgroups according to surface treatment method applied (2 W-, 3 W-, 4 W-, 5 W-, 6 W-laser irradiations and APA). Surface treatments were applied to pre-sintered groups before sintering and to post-sintered groups after sintering. Post-sintered heat-treated groups were subjected to veneer ceramic firing simulation after surface treatments. Flexural strength and flexural modulus values were statistically analysed and monoclinic phase content was calculated. Weibull analysis was used to evaluate strength reliability and fractographic analysis was conducted. RESULTS: Highest flexural strength values were detected at post-sintered no-heat APA and 4W-laser groups (P < 0.05). Pre-sintered groups showed statistically lower flexural strength values. Heat treatment decreased the strength of the specimens. Monoclinic phase content was only detected at post-sintered no-heat groups and the highest amount was detected at APA group. Rougher surfaces and deeper irregularities were detected at FE-SEM images pre-sintered groups. CONCLUSIONS: Application of surface treatments at pre-sintered stage may be detrimental for zirconia ceramics in terms of flexural strength. CLINICAL SIGNIFICANCE: Treating the surface of zirconia ceramic before sintering process is not recommended due to significant decrease in flexural strength values. 2 W-4 W Er,Cr:YSGG laser irradiations can be regarded as alternative surface treatment methods when zirconia restoration would be subjected to veneer ceramic firing procedures.


Assuntos
Abrasão Dental por Ar/métodos , Resistência à Flexão/efeitos da radiação , Lasers de Estado Sólido , Resistência ao Cisalhamento , Zircônio/química , Zircônio/efeitos da radiação , Compostos Inorgânicos de Carbono , Cerâmica/efeitos da radiação , Materiais Dentários , Temperatura Alta , Teste de Materiais , Microscopia Eletrônica de Varredura , Transição de Fase , Compostos de Silício , Propriedades de Superfície/efeitos da radiação , Resistência à Tração , Difração de Raios X
17.
Saudi Med J ; 39(2): 197-202, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29436570

RESUMO

OBJECTIVES: To evaluate the surface roughness of 4 different bulk-fill resin-based composites cured using different irradiance levels. Methods: This in vitro study was performed in February 2017 to August 2017 at the College of Dentistry, King Saud University. Twenty-four specimens were prepared from each of the bulk-fill materials [Tetric N-Ceram (TNC), SonicFill (SF), Smart Dentin Replacement (SDR), and Filtek Bulk-Fill (FB)] using a brass metal mold, resulting in a total of 96 specimens, cured using a Bluephase N light curing unit. Half of the total number of specimens (N=48) were cured using high-power irradiance (1200 mW/cm2) for 20 seconds, while the remaining half (N=48) were cured using low power irradiance (650 mW/cm2) for 40 seconds. After 24 hours, baseline surface roughness of each specimen was analyzed using a profilometer, then polished using Sof-lex abrasive disks, and the surface roughness of all groups was assessed. Results: Post-polished SonicFill cured at high irradiance had the highest mean surface roughness (0.23±0.03), whereas pre-polished Smart Dentin Replacement (0.11±0.01) and SonicFill (0.11±0.02) cured at low irradiance had the lowest mean surface roughness. Conclusion: High curing irradiance (1,200 mW/cm2) had no positive influence on the surface roughness of Filtek Bulk Fill and Tetric N-Ceram bulk-fill RBCs compared with lower curing irradiance (650 mW/cm2). However, the difference of curing irradiance significantly affected the surface roughness in SDR and sonic fill RBCs.


Assuntos
Resinas Compostas/efeitos da radiação , Cura Luminosa de Adesivos Dentários , Luz , Teste de Materiais , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo
18.
J Appl Oral Sci ; 26: e20160662, 2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29364336

RESUMO

The main goal of this study was to compare the polymerization degree of bulk-fill giomer resin cured with three different light-curing units (LCUs): a polywave third-generation (Valo); a monowave (DemiUltra: DU); and a second-generation LED (Optima 10: Opt) LCUs by using structural and mechanical properties. Giomer samples of 2 and 4 mm cured with three LCUs were employed in vitro analysis. The degree of curing (DC%) was determined with Fourier-Transform Infrared Spectroscopy (FTIR). Microstructural features were observed with scanning electron microscopy (SEM). Flexural strength (FS), compression strength (CS), elastic modulus and fracturing strain were determined for mechanical properties. Surface microhardness (SMH) values were also measured. Oneway ANOVA, two-way analysis of variance and Tukey multiple comparison tests were used for statistically analyzing the FS and SMH. DC% values were 58.2, 47.6, and 39.7 for the 2 mm samples cured with DU, Opt., and Valo LCUs, respectively. DC% values of the 4 mm samples were 50.4, 44.6, and 38.2 for DU, Opt, and Valo, respectively. SMH values were Valo, Opt

Assuntos
Bis-Fenol A-Glicidil Metacrilato/química , Bis-Fenol A-Glicidil Metacrilato/efeitos da radiação , Resinas Compostas/química , Resinas Compostas/efeitos da radiação , Cura Luminosa de Adesivos Dentários/métodos , Polimerização/efeitos da radiação , Análise de Variância , Força Compressiva , Módulo de Elasticidade , Testes de Dureza , Teste de Materiais , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo
19.
J Biosci Bioeng ; 125(5): 606-612, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29352711

RESUMO

Self-assembled monolayers (SAMs) have been used to elucidate interactions between cells and material surface chemistry. Gold surfaces modified with oligopeptide SAMs exhibit several unique characteristics, such as cell-repulsive surfaces, micropatterns of cell adhesion and non-adhesion regions for control over cell microenvironments, and dynamic release of cells upon external stimuli under culture conditions. However, basic procedures for the preparation of oligopeptide SAMs, including appropriate cleaning methods of the gold surface before modification, have not been fully established. Because gold surfaces are readily contaminated with organic compounds in the air, cleaning methods may be critical for SAM formation. In this study, we examined the effects of four gold cleaning methods: dilute aqua regia, an ozone water, atmospheric plasma, and UV irradiation. Among the methods, UV irradiation most significantly improved the formation of oligopeptide SAMs in terms of repulsion of cells on the surfaces. We fabricated an apparatus with a UV light source, a rotation table, and HEPA filter, to treat a number of gold substrates simultaneously. Furthermore, UV-cleaned gold substrates were capable of detaching cell sheets without serious cell injury. This may potentially provide a stable and robust approach to oligopeptide SAM-based experiments for biomedical studies.


Assuntos
Adesão Celular , Técnicas de Cultura de Células , Detergentes , Ouro/química , Oligopeptídeos/química , Tecidos Suporte/química , Adesão Celular/efeitos da radiação , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/efeitos da radiação , Cor , Reutilização de Equipamento , Multimerização Proteica , Propriedades de Superfície/efeitos da radiação , Raios Ultravioleta
20.
Photomed Laser Surg ; 36(2): 72-77, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29028438

RESUMO

OBJECTIVE: The aim of this review was to evaluate the balling phenomenon which occurs typically in Selective Laser Sintering (SLS). BACKGROUND DATA: The balling phenomenon is a typical SLS defect, and observed in laser sintered powder, significantly reduces the quality of SLS, and hinders the further development of SLS Technology. METHODS: Electronic database searches were performed using Google Scholar. The keywords "laser sintering, selective laser sintering, direct metal laser melting, and balling phenomenon" were searched in title/abstract of publications, limited to December 31, 2016. The inclusion criteria were SLS, balling phenomenon, some alloys (such as Cr-Co, iron, stainless steel, and Cu-based alloys) mechanical properties, microstructure and bond strength between metal-ceramic crown, laboratory studies, full text, and in English language. RESULTS: A total of 100 articles were found the initial search and yielded a total of 50 studies, 30 of which did not fulfill the inclusion criteria and were therefore excluded. In addition, 20 studies were found by screening the reference list of all included publications. Finally, 40 studies were selected for this review. CONCLUSIONS: The method in question is regulated by powder material characteristics and the conditions of laser processing. The procedure of formation, affecting factors, and the mechanism of the balling effect are very complex.


Assuntos
Ligas de Cromo/química , Colagem Dentária/instrumentação , Lasers , Terapia com Luz de Baixa Intensidade/métodos , Ligas Metalo-Cerâmicas/química , Técnica de Fundição Odontológica , Desenho de Equipamento , Humanos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Teste de Materiais , Controle de Qualidade , Estresse Mecânico , Propriedades de Superfície/efeitos da radiação
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