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1.
Braz Dent J ; 31(3): 201-220, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32667513

RESUMO

The effect of root canal preparation technique on microcrack initiation is a controversial issue. This systematic review aimed to assess the role of root canal preparation techniques with different kinematics (manual, rotary, reciprocating, adaptive, self-adjusting file) on microcrack initiation. In vitro and in situ studies comparing the influence of at least two different root canal preparation techniques on the initiation of dentin microcracks were searched in PubMed/MEDLINE and SCOPUS up to June 5, 2018 without language and period restriction. Two authors independently reviewed all identified titles and abstracts for eligibility. Tables were generated to summarize the included studies, and the included studies were assessed for bias. Fifty-four (n=54) articles met the eligibility criteria. The results were classified according to the method used for microcrack evaluation, and most studies that used micro-computed tomography showed no formation of new cracks after root canal preparation. In general, the instrumentation techniques induced microcrack formation when the methods were destructive, irrespective of kinematics. In relation to the apex region, when the preparation working length was set as the root canal length subtracted of 1 mm, the risk of microcrack initiation reduces. The majority of the included studies had low risk of bias for all assessed domains. Our results seem to indicate that the various root canal preparation techniques considered in this study will not cause damage to the dental structure when adequately employed and the proper methodology is applied.


Assuntos
Dentina , Preparo de Canal Radicular , Cavidade Pulpar , Microtomografia por Raio-X
2.
Braz Dent J ; 31(3): 272-280, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32667522

RESUMO

The purpose of this study was to evaluate the influence of the application mode of three universal adhesive systems on interfacial physical properties of indirect composite restorations adhesively cemented to dentin cavities. Seventy-eight bovine lower incisors were selected and a slice of dentin (thickness: 2 mm) between the buccal surface and pulp chamber was obtained for each tooth. Conical cavities were made on this surface. The internal walls of the cavities were then coated with a hydrophilic gel, filled with composite resin and photopolymerized. The dentin/cone sets were divided into 6 groups (n=10) according to type of universal adhesive (TETRI: Tetric N Bond, FUT: Futura Bond U, SBU: Single Bond Universal) and acid etching on dentin (A: with acid etching; WA: without acid etching). The acid etching and the adhesive systems were applied to the surface of the dentin. All composite resin cones were sandblasted (Al2O3, 20 s) and silanized. After surface treatment, the cones were cemented (RelyX Ultimate) into the dentin cavity and photopolymerized. After thermocycling (10,000 cycles), samples were submitted to marginal adaptation analysis (using caries detector dye), push-out test (0.5 mm/min), and failure mode analysis. Additional samples were prepared for nanoleakage analysis (SEM). The data (MPa) were analyzed by two-way ANOVA and Tukey's post-test (5%). The groups in which the dentin was acid etched showed significantly lower bond strength values in the push-out test (p<0.01). Dentin acid etching significantly reduced the bond strength between universal adhesive systems and dentin in indirect restorative procedures.


Assuntos
Colagem Dentária , Adesivos Dentinários , Animais , Bovinos , Resinas Compostas , Cimentos Dentários , Cavidade Pulpar , Dentina , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , Resistência à Tração
3.
Braz Dent J ; 31(3): 257-263, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32667523

RESUMO

The aim of this in vitro study was to determine the fluoride concentration in silver diamine fluoride (SDF) products and their bioavailability with demineralized dentine. The products evaluated (expected fluoride concentrations) were: I: Saforide 38% (45,283 ppm F); II: Advantage Arrest 38.3 to 43.2% (45,283 to 51,013 ppm F); III: Ancárie 12% (14,100 ppm F); IV: Ancárie 30% (35,400 ppm F), V: Cariestop 12% (14,100 ppm F) and VI: Cariestop 30% (35,400 ppm F). The fluoride concentration was evaluated using an ion-specific electrode (ISE) by direct technique, which was confirmed after microdiffusion. The pH of the products was determined with a pH test strip. For the bioavailability test, demineralized dentine slabs were treated with one of the products for 1 min. Loosely (CaF2-like) and firmly-bound fluoride (FAp) were determined. The fluoride concentration found in the products (mean±SD; ppm F) by the ISE direct technique was: I:53,491±554; II:57,249±1,851; III:4,814±268; IV:5,726±43; V:10,145±468; VI:11,858±575; these values were confirmed after microdiffusion (t-test; p>0.05) and disagree with the declared by the manufacturers. The pH of Ancárie 12 and 30% was 6.0 and 4.5, respectively, in disagreement with the alkaline pH expected for SDF solution and found in the other products evaluated. There was no correlation between either CaF2-like (r=0.221; p=0.337) or FAp (r=-0.144; p=0.830) formed in demineralized dentine and fluoride concentration found in the products. The problems of pH and fluoride concentration found in available professional commercial SDF products suggest that they are not under sanitary surveillance.


Assuntos
Cariostáticos , Fluoretos , Disponibilidade Biológica , Dentina , Fluoretos Tópicos , Concentração de Íons de Hidrogênio , Compostos de Amônio Quaternário , Compostos de Prata , Fluoreto de Sódio
4.
J Adhes Dent ; 22(4): 393-398, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32666065

RESUMO

PURPOSE: To assess the effect of the application of different electric currents on dentin bonding and resin infiltration of self-etching and etch-and-rinse adhesives. MATERIALS AND METHODS: Two hundred four sound third molars were selected and divided in groups according to the adhesive (self-etch [CSE, Clearfil SE Bond, Kuraray Noritake], universal [SBU, Single Bond Universal, 3M Oral Care], and etch-and-rinse [SB2, Adper Single Bond 2 (SB2), 3M Oral Care]) and electrical current used (0, 5, 10, 15, 20, 25, 30, and 35 µA). Light curing was performed for 10 s with an LED-curing unit at 1000 mW/cm2. Composite blocks were constructed of nanofilled composite in increments of 2 mm, which were light cured for 20 s. Specimens were sectioned into sticks with a cross-sectional area of ~1 mm2 and stored in distilled water at 37°C for 24 h. Microtensile bond strength (µTBS) testing (n = 8) was performed using a universal testing machine at a crosshead speed of 0.5 mm/min until failure. The bonding quality (n = 2) of adhesives applied with or without 35-µA electric current was evaluated using confocal laser scanning microscopy. Bond strengths were analyzed with two-way ANOVA and Tukey's test (α = 0.05). RESULTS: CSE presented the highest µTBS for all electrical currents tested. For CSE and SBU, electrical currents from 0-20 µA showed the lowest µTBS. Electrical currents from 0-10 and 20-25 µA yielded the lowest µTBS for SB2. CSE and SB2 applied under 35 µA showed a greater number of resin tags in dentin tubules. Fluorescein penetration into the hybrid layer was found for SBU applied without electric current. CONCLUSION: The application of adhesives using 35-µA electric current improved the bond strength and quality of the adhesive interface.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos , Resinas Compostas , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
5.
J Adhes Dent ; 22(4): 399-407, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32666066

RESUMO

PURPOSE: The aim of this study was to evaluate the chemomechanical properties, antibacterial activity, and cytotoxicity of an experimental adhesive resin containing halloysite nanotubes (HNT), doped with alkyl trimethyl ammonium bromide (ATAB). MATERIALS AND METHODS: A filler of HNT doped with ATAB was obtained (ATAB:HNT) and incorporated (5 wt%) into a resin blend made of bisphenol A glycerolate dimethacrylate, 2-hydroxyethyl methacrylate and a photoinitiator/co-initiator system (GATAB:HNT). The same resin blend without ATAB:HNT was used as control (Ctrl). The ATAB:HNT filler was assessed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The two tested adhesives were evaluated for degree of conversion (DC) in vitro and in situ, softening in alcohol, dentin microtensile bond strength (µTBS), antibacterial activity, and cytotoxicity (n = 5). RESULTS: SEM showed that the nanotubes had a characteristic tubular-needle morphology, while the TEM analysis confirmed the presence of ATAB inside the lumens of HNT. The incorporation of ATAB:HNT induced no reduction (p > 0.05) of the DC either in situ or in vitro. No difference was encountered after the softening challenge test (p > 0.05) and no difference was found in µTBS between the two adhesives, both at 24 h (p > 0.05) and after 6 months of storage in distilled water (p > 0.05). However, ATAB:HNT reduced Streptococcus mutans viability (p < 0.05) without a cytotoxic effect on pulp cells (p > 0.05). CONCLUSIONS: GATAB:HNT adhesive demonstrated appropriate polymerization without significant differences in softening after solvent immersion, while concomitantly maintaining reliable bond strength after 6 months of water aging. Moreover, the ATAB:HNT filler can provide antibacterial activity to the adhesive resin without affecting pulp cell viability.


Assuntos
Colagem Dentária , Nanotubos , Brometos , Argila , Cimentos Dentários , Dentina , Adesivos Dentinários , Teste de Materiais , Microscopia Eletrônica de Varredura , Compostos de Amônio Quaternário , Cimentos de Resina , Resistência à Tração
6.
J Adhes Dent ; 22(4): 415-420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32666068

RESUMO

PURPOSE: To investigate whether interfacial enzymatic activity and adhesion receptiveness of artificial caries-affected dentin (ACAD) simulate those of natural caries-affected dentin (NCAD). MATERIALS AND METHODS: Thirty dentin specimens were prepared from human molars to determine interfacial gelatinolytic activity using in situ zymography and adhesion experiments (micropermeability and bond strength [µTBS]). Groups were formed according to the type of dentin: artificial caries-affected dentin (ACAD), natural caries-affected dentin (NCAD), or sound dentin. ACAD was produced by incubating dentin with Streptococcus mutans in a chemically defined medium (CDM) with 1% sucrose for 7 days at 37°C under anaerobic conditions. CDM was replaced daily, and the sterility as well as the pH of the culture was monitored. Adhesion experiments employed Single Bond Universal (3M Oral Care) in self-etch mode. Data were individually processed and analyzed using ANOVA and post-hoc tests (α = 0.05). RESULTS: The enzymatic activity of ACAD was similar to that of sound dentin, but was lower than that of NCAD, which elicited the highest activity (p < 0.05). Interfacial micropermeability intensity at the hybrid layer or in underlying dentin (5 µm below the interface) was similar in all types of dentin (p > 0.05). On the other hand, substrate permeability was higher for NCAD than for ACAD. The highest sealing ability was detected in sound dentin. Bond strengths to ACAD were higher than to NCAD. However, the highest µTBS was observed in sound dentin (p < 0.05). CONCLUSION: Artificial caries-affected dentin simulated neither the gelatinolytic activity nor bonding receptiveness of natural caries-affected dentin.


Assuntos
Colagem Dentária , Cárie Dentária , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração
7.
Acta Odontol Latinoam ; 33(1): 27-32, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32621596

RESUMO

The aim of this study was to assess the influence of different pre-treatment approaches on glass ionomer cement (GIC) bond strength (BS) to dentine. Sixty bovine incisors were allocated into six groups according to substrate - sound or caries-affected dentine; and substrate pre-treatment approach - no conditioning (control), polyacrylic acid for 10 s and phosphoric acid for 7 s. Teeth in the caries-affected dentine group were previously submitted to cariogenic pH-cycling challenge. After dentine pre-treatment, according to experimental groups, polyethylene tubes were placed on flat dentine surfaces and filled with GIC. Teeth were stored in distilled water for 24 h at 37 °C and then submitted to microshear test (0.5 mm/min). Failure pattern analysis was performed under stereomicroscope (400x). Data were analysed using two-way ANOVA and Tukey's test (α=5%). Statistically significant differences were found for the pre-treatment approach, regardless of substrate (p<0.001). The polyacrylic acid group and control group had similar BS values, and were both better than the phosphoric acid group. In general, GIC had better bonding performance in sound dentine than in caries-affected dentine. In conclusion, dentine pre-treatment with polyacrylic acid did not improve the performance of GIC restoration on clinically relevant substrates.


Assuntos
Resinas Acrílicas/farmacologia , Colagem Dentária/métodos , Dentina/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/química , Animais , Bovinos , Infiltração Dentária/prevenção & controle , Dentina/diagnóstico por imagem , Dentina/patologia , Teste de Materiais
8.
Shanghai Kou Qiang Yi Xue ; 29(2): 213-216, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32626888

RESUMO

PURPOSE: To investigate the efficacy of autologous dentin particles combined with platelet-rich fibrin membrane (PRF) in the treatment of root bifurcation lesions of mandibular first molar. METHODS: Ninety-three patients (93 teeth) with mandibular first molar root bifurcation lesions were selected from our department from February 2016 to October 2017. They were randomly divided into 2 groups. Forty-six patients with 46 teeth in the experimental group underwent autologous dentin particles combined with platelet-rich fibrin membrane, while patents in the control group (47 patients with 47 teeth) were treated with Bio-Oss implanted in the bone defect area covered with collagen membrane. The patients were revisted at 1, 3, 6 and 12 months after operation. The success rate of the operation group, the depth of periodontal pocket (PD), the loss of attachment (AL), the depth of penetration of the root bifurcation (HPD), and the bone density of the root bifurcation area before and after treatment. The data were recorded and compared with SPSS25.0 software package. RESULTS: The success rate was 97.83%(45/46) in the experimental group, 85.11%(40/47) in the control group, the difference between the two groups was significant(P<0.05). After treatment, PD, AL and HPD decreased significantly (P<0.05), and MGVs increased gradually. There was no significant difference in MGVs before treatment and 1 month after treatment in the experimental group (P>0.05). MGVs at other time points were significantly higher than those of the control group (P<0.05). PD, AL and HPD of the experimental group were lower significantly than the control group at each time point after treatment (P<0.05), and MGVs value was significantly higher than the control group (P<0.05). There was no significant difference in the incidence of complications(4.35% vs 6.38%, χ2=0.189, P>0.05). CONCLUSIONS: Autologous dentin particles combined with platelet-rich fibrin membrane is effective for the treatment of root bifurcation lesions of mandibular first molar, which is worthy of wide application.


Assuntos
Fibrina Rica em Plaquetas , Densidade Óssea , Dentina , Humanos , Dente Molar , Bolsa Periodontal
9.
J Contemp Dent Pract ; 21(5): 515-520, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32690833

RESUMO

AIM: To evaluate in vitro effect of apical root canal perforation size on push-out bond strength of glass fiber dowels cemented to sound or perforated root canals using two different adhesive systems. MATERIALS AND METHODS: A total of 120 human-extracted intact upper central incisors were selected. Teeth were sectioned 3 mm coronal to cement enamel junction, and the remaining root received endodontic root canal therapy. The roots were divided into two experimental groups according to the root condition: either sound (n = 40) or apically perforated (n = 80). Dowel spaces were prepared for all specimens to a depth of 10 mm. Roots were restored with glass fiber dowels. The experimental group was further subdivided into four subgroups (n = 20) according to the adhesive system used and apical perforation size: group I, perforated root 2 mm apically, dowel cemented using total-etch adhesive cement; group II, perforated root 2 mm apically, dowel cemented using self-etch adhesive cement; group III, perforated root 4 mm apically, dowel cemented using total-etch adhesive cement; and group IV, perforated root 4 mm apically, dowel cemented using self-etch adhesive cement. The control group, sound root, was divided into two subgroups: group I, sound root, dowel cemented using total-etch adhesive cement, and group II, sound root, dowel cemented using self-etch or total-etch adhesive cement. Each root was then cut horizontally, and root segments were prepared to be tested. The bond strength between dowel and dentin was measured with universal testing machine using a push-out test. The two-way analysis of variance (ANOVA) was used to analyze the data and post hoc Tukey's test (α = 0.05). RESULTS: Root canal perforation and the type of adhesive system used resulted in significant differences in push-out bond strength (p < 0.05). Regardless of root canal perforation size, glass fiber dowels in normal root canals had significantly higher mean bond strength values (9.2 ± 1.4 MPa) compared with perforated root canals (6.1 ± 1.4 MPa). Also, self-etch protocol had significantly higher mean bond strength values (9.1 ± 1.3 MPa) compared with total-etch protocol (6.2 ± 2.1 MPa). CONCLUSION: The apical root perforation size caused a direct effect on the bond strength of the glass fiber dowels cemented to dentin by reducing the bond strength values to the root dentin regardless of the adhesive system used. CLINICAL SIGNIFICANCE: Prior to perforation repair, dentist or endodontist should evaluate the perforation size to predict the treatment outcome.


Assuntos
Colagem Dentária , Técnica para Retentor Intrarradicular , Cavidade Pulpar , Dentina , Vidro , Humanos , Teste de Materiais , Cimentos de Resina , Tratamento do Canal Radicular
10.
Stomatologiia (Mosk) ; 99(4): 15-20, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32692514

RESUMO

The study was aimed to conduct a morphological assessment of the influence exerted by a certain method of activation of endodontic rinsing liquid on the root dentin structure and canal cleaning effectiveness in an ex vivo experiment. The study was performed on 20 single-rooted teeth removed due to complicated caries in people aged 25-44 years. A devised method of vacuum-jet irrigation was used to carry out the final antiseptic treatment and to activate a rinsing liquid in the group No. 1 (n=10), and an endodontic syringe with ultrasonic activation was used in the group No. 2 (n=10). Optical and scanning electron microscopy data were used to assess dentin histostructure, presence or absence of organic inclusions in the root canal lumens, quality of preparation and contour lines of their sides. An analysis of scans demonstrates that the vacuum-jet irrigation method effectively cleans the root canal lumen in the apical area in 90% of the cases, while irrigation with an endodontic syringe and ultrasound activation has been effective in 67% of the cases. The smear layer throughout the root canals in the samples of the group No. 1 was removed in 100% of the cases. At the same time, the smear layer in the canal apical area was not completely removed in either of the samples of the group No. 2. An analysis of photomicrographs of histotopographic cross sections of the dental roots in group No. 2 under consideration revealed numerous cavities in the circumpulpal dentin, which form nidi of destruction up to 10-15 mcr in diameter merging in the cervical and middle third of the root. At the same time, a typical structure of the circumpulpal dentin with a well-developed network of dentinal tubules and intact peritubular and intertubular matrix was observed throughout the dental roots in the samples of the group No. 1. These investigational studies allow us to conclude that vacuum-jet irrigation of root canals provides better cleaning, completely removes the smear layer and does not damage the root dentin structure.


Assuntos
Cavidade Pulpar , Camada de Esfregaço , Adulto , Dentina , Ácido Edético , Humanos , Microscopia Eletrônica de Varredura , Irrigantes do Canal Radicular , Preparo de Canal Radicular , Hipoclorito de Sódio
11.
Stomatologiia (Mosk) ; 99(3): 7-10, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32608941

RESUMO

OBJECTIVE: To study the dynamics of changes in the adhesion between the composite and dentin of the tooth when using different volumes of a single-component adhesive system in case of contamination of it with human blood plasma. MATERIAL AND METHODS: To achieve this goal, the following were used: extracted human teeth, XP Bond one-component adhesive systems (DENTSPLY, Germany), Esthet X HD micrometric restoration material (DENTSPLY, Germany), and centrifuged blood plasma. The strength of the adhesive bond between the composite material and the hard tissues of the tooth was studied using a shear test machine Zwick Roell Z 010 («Zwick¼, Germany). RESULTS: The use of a single-component adhesive system in an amount of 17.7 mg (1 drop from a dispenser) for treating open dentin makes it more resistant to contamination compared to using the same adhesive, but in an amount of 6.6 mg (the amount of adhesive that adsorbs a medium-sized dental take). A decrease in the adhesion force between the composite material and tooth hard tissues from 1.5 to 17.7% occurs when a single-component adhesive system weighing 17.7 mg of blood plasma simulating a dentinal fluid weighing from 0.2 to 2.0 mg enters. The ingestion of the same amount of blood plasma in a single-component adhesive system weighing 6.6 mg leads to a decrease in its adhesion from 4.3 to 43%.


Assuntos
Colagem Dentária , Resinas Compostas , Cimentos Dentários , Análise do Estresse Dentário , Dentina , Humanos , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
12.
J Indian Soc Pedod Prev Dent ; 38(2): 138-144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32611859

RESUMO

Background: Use of silver diamine fluoride (SDF) after selective caries excavation can arrest the further progress of the carious lesion. Application of potassium iodide (KI) can reduce the staining due to SDF. Aim: The aim of the study was to evaluate the effect of the application of SDF, with and without acid etching and KI on the bond strength of resin-modified glass ionomer cement (RMGIC) to the carious dentin of primary teeth. Materials and Methods: In thisin vitro study, caries was induced on the occlusal surface by inoculating Streptococcus mutans strain in 36 extracted primary molars. The teeth were divided into four groups (n = 9), and the following treatments were done to the carious dentin prior to final restoration with RMGIC: Group I: 10% polyacrylic acid conditioner, Group II: 38% SDF, Group III: 37% phosphoric acid etchant followed by 38% SDF, and Group IV: 37% phosphoric acid etchant followed by 38% SDF and 10% potassium iodide solution. The microtensile bond strength was measured using universal testing machine. Failure modes were recorded using a scanning electron microscope. Results: There was no significant difference in microtensile bond strengths between the groups (P = 0.665), with the highest value seen in Group III. Conclusions: Application of SDF with or without acid etching and KI does not affect the bond strength of RMGIC to carious dentin of primary teeth.


Assuntos
Colagem Dentária , Cárie Dentária , Dentina , Adesivos Dentinários , Fluoretos Tópicos , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Compostos de Amônio Quaternário , Cimentos de Resina , Compostos de Prata , Resistência à Tração , Dente Decíduo
13.
Shanghai Kou Qiang Yi Xue ; 29(2): 150-154, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32626877

RESUMO

PURPOSE: To evaluate the effect of 2% chlorhexidine(CHX) on the self-etching adhesive to dentin. METHODS: Fifty carious free molars were selected to expose the flat dentin surface. The specimens were bonded with composite resin by self-etching adhesive ,which were pretreated by 2% CHX for 0, 15, 30, 45 and 60 s. The microtensile bond strength (µTBS) and scanning electron microscope(SEM) were evaluated before and after thermocycling. SPSS 19.0 software package was used for statistical analysis. RESULTS: µTBS of the 45 and 60s-CHX pretreated group had significant difference before thermocycling, significantly higher than the control group(P<0.05). The 60s-CHX pretreated group showed significant greater µTBS than the control group after thermocycling(P<0.05). CONCLUSIONS: 2%CHX pretreatment can improve the bonding strength of the self-etching adhesive, and slow down the aging progress of bonding interface.


Assuntos
Clorexidina , Colagem Dentária , Resinas Compostas , Cimentos Dentários , Dentina , Adesivos Dentinários , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina , Estresse Mecânico , Resistência à Tração
14.
J Contemp Dent Pract ; 21(4): 426-430, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32584281

RESUMO

AIM: The aim of this study was to evaluate and compare various conditioning regimes (laser and conventional) on shear bond strength (SBS) of resin-modified glass ionomer cement (RMGIC) bonded to dentin. MATERIALS AND METHODS: Sixty non-carious intact maxillary molars were cleaned, isolated, and randomly divided into six groups (n = 10). Before randomization, the dentin surface was exposed and finished. Samples in group I were conditioned using Er,Cr:YSGG laser (ECYL). Specimens in group II were conditioned using Er:YAG laser (EYL), and the dentin surfaces of specimens in group III and group IV were conditioned using cavity conditioner and K930. Similarly, the samples in group V and group VI were surface treated using 17% EDTA and total etch. All samples were bonded with RMGIC following conditioning regime. For SBS testing, the samples were placed in universal testing machine. A fracture analysis of debonded surfaces was evaluated using stereomicroscope at 40× magnification. Means and standard deviations (SDs) were calculated using analysis of variance (ANOVA) and Tukey's post hoc test at a significant level of p < 0.05. RESULTS: The maximum bond strength values were observed in group VI total etch (23.85 ± 3.67). The lowest bond strength was displayed in laser dentin group II conditioned by EYL (11.65 ± 2.77). Dentin conditioned with ECYL, cavity conditioner, K930 conditioner, and 17% ethylenediaminetetraacetic acid (EDTA) were found to be comparable, p > 0.05. Cohesive failure was dominant among experimental groups. CONCLUSION: Er,Cr:YSGG laser has a potential to be recommended for dentin conditioning prior to application of RMGIC. CLINICAL SIGNIFICANCE: Dentin conditioning enhances adhesion of RMGIC for improved prognosis and treatment outcome.


Assuntos
Colagem Dentária , Lasers de Estado Sólido , Dentina , Cimentos de Ionômeros de Vidro , Teste de Materiais , Resistência ao Cisalhamento
15.
Int J Nanomedicine ; 15: 3921-3936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581537

RESUMO

Background: Mesoporous calcium-silicate nanoparticles (MCSNs) have good prospects in the medical field due to their great physicochemical characteristics, antibacterial activity and drug delivery capacity. This study was to analyze the antibiofilm activity and mechanisms of silver (Ag) and zinc (Zn) incorporated MCSNs (Ag/Zn-MCSNs) with different percentages of Ag and Zn. Methods: Ag/Zn(1:9, molar ratio)-MCSNs and Ag/Zn(9:1, molar ratio)-MCSNs were prepared and characterized. Endocytosis of nanoparticles by Enterococcus faecalis (E. faecalis) treated with Ag/Zn-MCSNs was observed using TEM to explore the antibacterial mechanisms. The antibiofilm activity of Ag/Zn-MCSNs with different ratios of Ag and Zn was tested by E. faecalis biofilm model in human roots. The human roots pretreated by different Ag/Zn-MCSNs were cultured with E. faecalis. Then, SEM and CLSM were used to observe the survival of E. faecalis on the root canal wall. Cytotoxicity of the nanoparticles was tested by CCK8 kits. Results: The Ag/Zn-MCSNs release Ag+ and destroy the cell membranes to kill bacteria. The MCSNs containing Ag showed antibacterial activity against E. faecalis biofilms in different degrees, and they can adhere to dentin surfaces to get a continuous antibacterial effect. However, MTA, MCSNs and Zn-MCSNs could not disrupt the bacterial biofilms obviously. MCSNs, Ag/Zn(1:1, molar ratio)-MCSNs and Ag/Zn(1:9)-MCSNs showed no obvious cytotoxicity, while Ag-MCSNs and Ag/Zn(9:1)-MCSNs showed cytotoxicity. Zn-MCSNs can slightly promote cell proliferation. Conclusion: Ag/Zn-MCSNs have good antibiofilm activity. They might achieve an appropriate balance between the antibacterial activity and cytotoxicity by adjusting the ratio of Ag and Zn. Ag/Zn-MCSNs are expected to be a new type of root canal disinfectant or sealer for root canal treatment.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Nanopartículas/química , Prata/química , Zinco/química , Animais , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Compostos de Cálcio/química , Cavidade Pulpar/microbiologia , Dentina/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Humanos , Camundongos , Osteoblastos/efeitos dos fármacos , Porosidade , Silicatos/química , Prata/farmacologia , Zinco/farmacologia
16.
J Endod ; 46(8): 1099-1104, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32479803

RESUMO

INTRODUCTION: This study focused on the optimization of sodium hypochlorite-EDTA irrigation in terms of the viability and morphology of dental pulp stem cells (DPSCs) and the effects of an optimized EDTA protocol alone or prepared with nanobubble (NB) water on cell behavior. METHODS: In the first part, human dentin discs were conditioned with the following protocols: (1) Sodium hypochlorite followed by phosphate-buffered saline (PBS), (2) Irrigation protocol from group 1 followed by EDTA, (3) Irrigation protocol from group 2 followed by PBS, (4) Sodium hypochlorite followed by EDTA, (5) Irrigation protocol from group 4 followed by PBS. DPSC viability and morphology were determined. In the second part, dentin discs were conditioned with the (1) optimized protocol in the first part, (2) EDTA prepared using NB water, (3) ultrasonic-activated EDTA, or (4) ultrasonic-activated EDTA prepared using NB water. Transforming growth factor beta release and DPSC viability, morphology, and migration were determined using the enzyme-linked immunosorbent assay, the water-soluble tetrazolium salt-1 cell viability assay and live-dead assay, and the transwell migration assay, respectively. Data were analyzed using Kruskal-Wallis or one-way analysis of variance and post hoc tests. RESULTS: The highest cell viability was observed in group 3 followed by group 5 (P < .05) in which PBS was used as a final rinse. Irrigation protocol from group 3 was used for the subsequent experiments. Ultrasonic-activated EDTA improved transforming growth factor beta release, viability, and migration of the cells compared with EDTA (P < .05). The preparation of EDTA with NBs did not change the biological properties of the EDTA-conditioned dentin (P > .05). CONCLUSIONS: Removing the residual EDTA using PBS improved the cell viability on the dentin surface. Ultrasonic activation enhanced the growth factor release and biological properties, whereas the preparation of EDTA with NBs showed a similar effect to regular EDTA without compromising the cellular effect.


Assuntos
Endodontia Regenerativa , Cavidade Pulpar , Dentina , Ácido Edético , Humanos , Irrigantes do Canal Radicular , Hipoclorito de Sódio
17.
Braz Dent J ; 31(2): 179-185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32556018

RESUMO

The aim was to evaluate, in vitro, the influence of pH cycling on microtensile bond strength (µTBS) and percentage of nanoleakage (%NL) in the dentin-adhesive interface. Flat dentin surfaces were obtained in 56 extracted third molars. The teeth were randomly divided into four groups (n=14): G1- Single Bond Universal (etch-and-rinse mode); G2- Single Bond Universal (self-etch mode); G3- Scotchbond Multi-Purpose; G4- Clearfil SE Bond. A block of composite was built on the adhesive area. Eight tooth/resin sets were cut parallel to the tooth's long axis to obtain 48 beams (0.8 mm2) for each group. Half of the beams were submitted to four cycles of pH cycling (demineralizing solution for 6 h and remineralizing solution for 18 h). The samples were submitted to µTBS test in a universal testing machine. Six tooth/resin sets were cut parallel to the tooth's long axis to obtain three slices of the central region (1.0 mm thickness). Half of the slices were submitted to pH cycling. The nanoleakage methodology was applied to obtain the %NL at the adhesive interfaces. According to two-way ANOVA, the interaction between factors (adhesive system x storage) was significant (p=0.0001) for µTBS and %NL. After pH cycling, there was a significant decrease in µTBS and a significant increase in %NL for all adhesives. The adhesives applied in the self-etch mode obtained lower %NL, differing significantly from the etch-and-rinse adhesives. It was concluded that the pH cycling negatively influenced the µTBS and %NL for all adhesives evaluated. However, self-etch adhesives allowed less %NL.


Assuntos
Colagem Dentária , Adesivos Dentinários , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
18.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(3): 256-262, 2020 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-32573131

RESUMO

OBJECTIVE: This study aimed to develop novel self-adhesive resin cement with antibacterial and self-healing properties. Furthermore, the dentin bonding strength, mechanical properties, self-healing efficiency, and antibacterial property of the developed cement were measured. METHODS: Novel nano-antibacterial inorganic fillers that contain quaternary ammonium salts with long-chain alkyls were synthesized. These fillers were added into self-adhesive resin cement containing self-healing microcapsules at mass fractions of 0, 2.5%, 5.0%, 7.5%, or 10.0%. The dentin shear bonding test was used to test the bonding strength, whereas the flexural test was used to measure the flexural strength and elastic modulus of the cement. The single-edge V-notched beam method was used to measure self-healing efficiency, and human dental plaque microcosm biofilms were chosen to calculate the antibacterial property. RESULTS: The dentin shear bond strength significantly decreased when the mass fraction of the nano-antibacterial inorganic fillers in the novel cement reached 7.5% (P<0.05). The incorporation of 0, 2.5%, 5.0%, 7.5%, or 10.0% mass fraction of nano-antibacterial inorganic fillers did not adversely affect the flexural strength, elastic modulus, fracture toughness, and self-healing efficiency of the cement (P>0.1). Resin cement containing 2.5% mass fraction or more nano-antibacterial inorganic fillers significantly inhibited the metabolic activity of dental plaque microcosm biofilms, indicating strong antibacterial potency (P<0.05). CONCLUSIONS: The novel self-adhesive resin cement exhibited promising antibacterial and self-healing properties, which enable the cement to be used for dental applications.


Assuntos
Colagem Dentária , Cimentos de Resina , Antibacterianos , Cimentos Dentários , Análise do Estresse Dentário , Dentina , Humanos , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície
19.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(3): 314-318, 2020 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-32573141

RESUMO

Tubular dentin is of great significance in the process of tooth tissue and tooth regeneration, because it is not only the structural feature of primary dentin, but also can affect the tooth sensory function, affect the differentiation of dental pulp cells and provide strong mechanical support for teeth. Scaffold is one of the three elements of tissue engineering dentin regeneration. Most experiments on dentin regeneration involve the study of the microstructure and mechanical properties of the scaffold. The microstructure and mechanical characteristics of scaffold materials have important effects on the differentiation and adhesion of odontoblast, it can directly affect the tissue structure of regenerated dentin.


Assuntos
Polpa Dentária , Tecidos Suporte , Diferenciação Celular , Dentina , Odontoblastos , Regeneração , Engenharia Tecidual
20.
Niger J Clin Pract ; 23(6): 792-797, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32525113

RESUMO

Background: There is no information about the shear bond strengths (SBS) of zirconia ceramic to primary tooth dentin. Aim: To investigate the effect of different surface treatments and cements on the shear bond strength (SBS) of zirconia ceramic to primary tooth dentin. Materials and Methods: Prepared zirconia bars were distributed into four groups according to surface treatment procedure: control, sandblasting, CoJet and hot etching. The zirconia specimens in each group were further divided into subgroups according to cement (n = 13): self-adhesive resin (Rely-X Unicem), resin-modified glass ionomer (Ketac-Cem Plus), and universal bioactive (BioCem). Zirconia specimens were bonded to the primary tooth dentin surface by cement. SBS was measured, and the data were subjected to two-way ANOVA and Tukey's tests. Results: Statistical differences were observed in the surface treatment procedures for Rely-X Unicem (P < 0.05), but no statistically significant differences were found in the sandblasting, CoJet and hot-etching groups for Ketac-Cem Plus (P > 0.05). For BioCem, the SBS value for the hot etching group was significantly lower than those for the CoJet and sandblasting groups (P < 0.05). The SBS values for the Rely-X Unicem subgroups (sandblasting, CoJet and hot etching) were significantly higher than those for the other cements (P < 0.05). Conclusion: The bond strength of zirconia ceramic to primary tooth dentin is affected by surface treatments and cements.


Assuntos
Cerâmica/química , Colagem Dentária , Dentina , Cimentos de Resina/química , Resistência ao Cisalhamento , Dente Decíduo , Zircônio/química , Resinas Acrílicas , Adesivos , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Dióxido de Silício , Propriedades de Superfície
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