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1.
J Endod ; 45(5): 651-659, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30833094

RESUMO

The purpose of this study was to report the clinical efficacy of decompression for 3 cases with large periapical lesions and to review technique details. Three cases with large periapical cystic lesions were treated with decompression after root canal treatment. A traditional decompression technique was used for the first case. After aspiration, mucogingival incision, irrigation, and incisional biopsy, a pediatric endotracheal tube was sutured in place and kept for 3 weeks for lesion debridement. An aspiration/irrigation technique was adopted for the second case. An 18-G needle with a syringe was used to aspirate the cystic lesion. Two needles were then inserted into the lesion; copious saline irrigation was delivered from 1 needle and until clear saline was expressed from the other. For the third case, decompression was accomplished with a surgical catheter that was subsequently replaced with a gutta-percha plug after 1 month. None of the 3 cases underwent complete enucleation and root-end surgery. Healed lesions or lesions in healing were observed after 1 to 2 years. Based on the presented cases and published case reports on decompression, a literature review was provided covering indications, technique details, modification, and prognosis of decompression in endodontics. For large periapical cystic lesions, conservative decompression may be used for certain cases before or in lieu of apical surgery. Decompression enables healing of large, persistent periapical lesions after root canal treatment.


Assuntos
Cisto Radicular , Tratamento do Canal Radicular , Criança , Guta-Percha , Humanos , Prognóstico , Cisto Radicular/terapia , Resultado do Tratamento
2.
Adv Sci (Weinh) ; 5(10): 1800873, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30356983

RESUMO

Biomineralization in vertebrates is initiated via amorphous calcium phosphate (ACP) precursors. These precursors infiltrate the extracellular collagen matrix where they undergo phase transformation into intrafibrillar carbonated apatite. Although it is well established that ACP precursors are released from intracellular vesicles through exocytosis, an unsolved enigma in this cell-mediated mineralization process is how ACP precursors, initially produced in the mitochondria, are translocated to the intracellular vesicles. The present study proposes that mitophagy provides the mechanism for transfer of ACP precursors from the dysfunctioned mitochondria to autophagosomes, which, upon fusion with lysosomes, become autolysosomes where the mitochondrial ACP precursors coalesce to form larger intravesicular granules, prior to their release into the extracellular matrix. Apart from endowing the mitochondria with the function of ACP delivery through mitophagy, the present results indicate that mitophagy, triggered upon intramitochondrial ACP accumulation in osteogenic lineage-committed mesenchymal stem cells, participates in the biomineralization process through the BMP/Smad signaling pathway.

3.
J Oral Sci ; 59(4): 527-532, 2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-29151458

RESUMO

This in vivo study aimed to evaluate the efficacy of in-office and home teeth bleaching in Asian patients. Moreover, the correlation between tooth color change and patient's outcome satisfaction was investigated. Overall, 40 Chinese patients were randomly divided into two groups and prescribed in-office (OB) or take-home bleaching (HB). The color of the maxillary central incisor and canine were recorded at baseline, immediately after first treatment, 1 week, and 3 months after treatment by using a spectrophotometer. Bleaching sensitivity and outcome satisfaction were assessed using Likert and visual analogue scale (VAS), and the results were analyzed using independent t-test and Pearson correlation (P < 0.05). ΔL*, Δa*, Δb*, and ΔE* values of HB were greater than those of OB. Color changes observed in canines were generally greater than those in incisors. Moreover, HB was generally associated with less tooth sensitivity than OB. Patients were satisfied with both treatments, but VAS scores were greater for HB. Furthermore, the correlation between ΔE* and VAS was significant for canines immediately after the first treatment and 1 week after HB. In conclusion, HB was more effective in lightening teeth and reducing chromacity in Chinese patients. The correlation between tooth color change and outcome satisfaction was generally insignificant and weak.


Assuntos
Grupo com Ancestrais do Continente Asiático , Consultórios Odontológicos , Serviços de Assistência Domiciliar , Satisfação do Paciente , Clareamento Dental , Adulto , China , Cor , Feminino , Humanos , Masculino , Resultado do Tratamento , Adulto Jovem
4.
Acta Biomater ; 57: 435-448, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28499631

RESUMO

Limitations associated with wet-bonding led to the recent development of a selective demineralization strategy in which dentin was etched with a reduced concentration of phosphoric acid to create exclusive extrafibrillar demineralization of the collagen matrix. However, the use of acidic conditioners removes calcium via diffusion of very small hydronium ions into the intrafibrillar collagen water compartments. This defeats the purpose of limiting the conditioner to the extrafibrillar space to create a collagen matrix containing only intrafibrillar minerals to prevent collapse of the collagen matrix. The present work examined the use of polymeric chelators (the sodium salt of polyacrylic acid) of different molecular weights to selectively demineralize extrafibrillar dentin. These polymeric chelators exhibit different affinities for calcium ions (isothermal titration calorimetry), penetrated intrafibrillar dentin collagen to different extents based on their molecular sizes (modified size-exclusion chromatography), and preserve the dynamic mechanical properties of mineralized dentin more favorably compared with completely demineralized phosphoric acid-etched dentin (nanoscopical dynamic mechanical analysis). Scanning and transmission electron microscopy provided evidence for retention of intrafibrillar minerals in dentin surfaces conditioned with polymeric chelators. Microtensile bond strengths to wet-bonded and dry-bonded dentin conditioned with these polymeric chelators showed that the use of sodium salts of polyacrylic acid for chelating dentin prior to bonding did not result in significant decline in resin-dentin bond strength. Taken together, the findings led to the conclusion that a chelate-and-rinse conditioning technique based on extrafibrillar collagen demineralization bridges the gap between wet and dry dentin bonding. STATEMENT OF SIGNIFICANCE: The chelate-and-rinse dental adhesive bonding concept differentiates from previous research in that it is based on the size-exclusion characteristics of fibrillar collagen; molecules larger than 40kDa are prevented from accessing the intrafibrillar water compartments of the collagen fibrils. Using this chelate-and-rinse extrafibrillar calcium chelation concept, collagen fibrils with retained intrafibrillar minerals will not collapse upon air-drying. This enables adhesive infiltration into the mineral-depleted extrafibrillar spaces without relying on wet-bonding. By bridging the gap between wet and dry dentine bonding, the chelate-and-rinse concept introduces additional insight to the field by preventing exposure of endogenous proteases via preservation of the intrafibrillar minerals within a collagen matrix. If successfully validated, this should help prevent degradation of resin-dentine bonds by collagenolytic enzymes.


Assuntos
Colágeno/química , Dentina/química , Dente Molar/química , Desmineralização do Dente , Humanos
6.
Acta Biomater ; 38: 190-200, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27130275

RESUMO

UNLABELLED: To investigate the contribution of nanolayering on resin-dentin bond durability, two phosphoric acid ester resin monomers, 10-methacryloyloxy-decyl-dihydrogen-phosphate (10-MDP) or its analog, methacryloyloxy-penta-propyleneglycol-dihydrogen-phosphate (MDA), were examined for their affinity for mineralized dentin powder in a column chromatography setup. Hydroxyapatite (HA) powder was dispersed in experimental primers consisting of 10-MDP or MDA solvated in ethanol/water and examined with FTIR, (31)P MAS-NMR and XPS. Light-curable 10-MDP or MDA primers were used for bonding to dentin, and examined after 24h or one-year of water-aging by TEM for evidence of nanolayering, and for microtensile bond strength evaluation. Primer-bonded dentin was examined by thin-film XRD to identify short-range order peaks characteristic of nanolayering of resin monomer-Ca salts. Although 10-MDP had better affinity for mineralized dentin than MDA, both monomers completely eluted from the mineralized dentin powder column using ethanol-water as mobile phase, indicating that the adsorption processes were reversible. This finding was supported by chemoanalytic data. XRD of 10-MDP-bonded dentin showed three diffraction peaks hat were absent from MDA-bonded dentin. Nanolayering was identified by TEM in 10-MDP-bonded dentin, but not in MDA-bonded dentin. Significant drop in bond strength (in MPa) was observed for both groups after one-year of water-aging compared with 24-h: 10-MDP group from 48.3±6.3 to 37.4±4.6; MDA group from 50.7±5.0 to 35.7±3.8 (P<0.05), with no significant difference between the two groups at the same time-point. Because both functional monomer-primed, resin-bonded dentin exhibited similar bond strength decline after water-aging, presence of nanolayering is unlikely to contribute to the overall resin-dentin bond durability. STATEMENT OF SIGNIFICANCE: The durability of resin-dentin bonds in 10-MDP containing self-etching adhesives has been anecdotally attributed to the presence of nanolayering of 10-MDP-calcium salts in the resin-dentin interface. Results of the present work indicate that such a claim cannot be justified. Complete elution of the phosphoric acid ester monomer from mineralized dentin powder in the column chromatography experiments using ethanol-water mobile phase to simulate the solvent mixture employed in most 10-MDP-containing dentin adhesives further challenges the previously proposed adhesion-decalcification concept that utilizes chemical bonding of phosphoric acid ester monomers to apatite as a bonding mechanism in 10-MDP containing dentin adhesives.


Assuntos
Dentina/química , Durapatita , Metacrilatos , Dente Molar/química , Resinas Sintéticas , Tiazolidinedionas , Durapatita/química , Durapatita/farmacologia , Humanos , Metacrilatos/química , Metacrilatos/farmacologia , Resinas Sintéticas/química , Resinas Sintéticas/farmacologia , Tiazolidinedionas/química , Tiazolidinedionas/farmacologia
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 57-62, 2016 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-26885909

RESUMO

OBJECTIVE: To investigate the antibacterial effect of different self-etching adhesive systems against Streptococcus mutans (S. mutans). METHODS: Six reagents Clearfil(TM) SE Bond primer (SP), Clearfil(TM) SE Bond adhesive (SA),Clearfil(TM) Protect Bond primer (PP), which contained antibacterial monomer methacryloyloxydodecylpyridinium bromide (MDPB), ClearfilTM Protect Bond adhesive (PA), positive control chlorhexidine acetate [CHX, 1% (mass fraction)], and negative control phosphate buffer solution (PBS) were selected. They were mixed with S. mutans for 30 s respectively, then colony-forming units (CFU) were counted after incubated for 48 h on brain heart infusion (BHI) agar medium. The 6 reagents were applied to the sterile paper discs, and distributed onto the BHI agar medium with S. mutans and incubated for 24 h, then the inhibition zones were observed. CHX, PBS, PP, and SP were added on the dentin with artificial caries induced by S. mutans and kept for 30 s, then confocal laser scanning microscope (CLSM) was used to observe the live and dead bacteria after staining. The ratio of live to dead bacteria was calculated. PP+PA and SP+SA were applied on the dentin according to the manual and light cured. S. mutans were incubated on the samples for 2 h, ultrasonically treated and incubated on BHI agar medium for 48 h, then CFU was counted. The data were analyzed by non-parametric analysis and one-way ANOVA. RESULTS: Compared with PBS, the PP, SP, PA, SA and CHX showed the antibacterial effect on free S. mutans (P<0.05); SP and PP showed stronger antibacterial effect than PA, SA and CHX (P<0.05). CHX, SP and PP presented inhibition zones, while PBS, SA and PA did not. Compared with PBS, the CHX, SP and PP could lower the ratio of the live to dead bacteria significantly (P<0.05). Cured self-etching adhesive systems did not show any antibacterial effect on the free S. mutans. CONCLUSION: The primer of self-etching adhesives Clearfil(TM) SE Bond and Clearfil(TM) Protect Bond showed significant antibacterial effect on free and attached S. mutans. The adhesive only showed antibacterial effect on free S. mutans before light-cured polymerization. After being cured, the self-etching adhesive systems did not show antibacterial effect anymore.


Assuntos
Adesivos/química , Antibacterianos/farmacologia , Corrosão Dentária , Adesivos Dentinários/química , Streptococcus mutans/efeitos dos fármacos , Cárie Dentária , Dentina/química , Humanos , Compostos de Piridínio/farmacologia
8.
J Dent ; 45: 43-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26655173

RESUMO

OBJECTIVES: The present study evaluated the long-term dentine bonding effectiveness of five universal adhesives in etch-and-rinse or self-etch mode after 12 months of water-ageing. METHODS: The adhesives evaluated included All-Bond Universal, Clearfil Universal Bond, Futurabond U Prime&Bond Elect and Scotchbond Universal. Microtensile bond strength and transmission electron microscopy of the resin-dentine interfaces created in human coronal dentine were examined after 24h or 12 months. RESULTS: Microtensile bond strength were significantly affected by bonding strategy (etch-and-rinse vs self-etch) and ageing (24h vs 12 months). All subgroups showed significantly decreased bond strength after ageing except for Prime&Bond Elect and Scotchbond Universal used in self-etch mode. All five adhesives employed in etch-and-rinse mode exhibited ultrastructural features characteristic of collagen degradation and resin hydrolysis. A previously-unobserved inside-out collagen degradation pattern was identified in hybrid layers created by 10-MDP containing adhesives (All-Bond Universal, Scotchbond Universal and Clearfil Universal Bond) in the etch-and-rinse mode, producing partially degraded collagen fibrils with intact periphery and a hollow core. In the self-etch mode, all adhesives except for Prime&Bond Elect exhibited degradation of the collagen fibrils along the thin hybrid layers. The three 10-MDP containing universal adhesives did not protect surface collagen fibrils from degradation when bonding was performed in the self-etch mode. CONCLUSIONS: Despite the adjunctive conclusion that bonds created by universal adhesives in the self-etch bonding mode are more resistant to decline in bond strength when compared with those bonds created using the etch-and-rinse mode, bonds created by universal adhesives are generally incapable of defying ageing.


Assuntos
Colagem Dentária , Cimentos Dentários/química , Esmalte Dentário/ultraestrutura , Adesivos Dentinários/química , Dentina/ultraestrutura , Teste de Materiais , Condicionamento Ácido do Dente/métodos , Bis-Fenol A-Glicidil Metacrilato/química , Colágeno/metabolismo , Resinas Compostas/química , Dentina/diagnóstico por imagem , Adesivos Dentinários/classificação , Humanos , Metacrilatos/química , Ácidos Fosfóricos , Ácidos Polimetacrílicos/química , Cimentos de Resina/química , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Água/química
9.
Dent Mater ; 31(12): 1510-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26494267

RESUMO

OBJECTIVES: In pulpal revascularization, a protective material is placed coronal to the blood clot to prevent recontamination and to facilitate osteogenic differentiation of mesenchymal stem cells to produce new dental tissues. Although mineral trioxide aggregate (MTA) has been the material of choice for clot protection, it is easily displaced into the clot during condensation. The present study evaluated the effects of recently introduced calcium silicate cements (Biodentine and TheraCal LC) on the viability and osteogenic differentiation of human dental pulp stem cells (hDPSCs) by comparing with MTA Angelus. METHODS: Cell viability was assessed using XTT assay and flow cytometry. The osteogenic potential of hDPSCs exposed to calcium silicate cements was examined using qRT-PCR for osteogenic gene expressions, alkaline phosphatase enzyme activity, Alizarin red S staining and transmission electron microscopy of extracellular calcium deposits. Parametric statistical methods were employed for analyses of significant difference among groups, with α=0.05. RESULTS: The cytotoxic effects of Biodentine and TheraCal LC on hDPSCs were time- and concentration-dependent. Osteogenic differentiation of hDPSCs was enhanced after exposure to Biodentine that was depleted of its cytotoxic components. This effect was less readily observed in hDPSCs exposed to TheraCal LC, although both cements supported extracellular mineralization better than the positive control (zinc oxide-eugenol-based cement). SIGNIFICANCE: A favorable tissue response is anticipated to occur with the use of Biodentine as a blood clot-protecting material for pulpal revascularization. Further investigations with the use of in vivo animal models are required to validate the potential adverse biological effects of TheraCal LC on hDPSCs.


Assuntos
Compostos de Alumínio/química , Bismuto/química , Compostos de Cálcio/química , Cimentos Dentários/química , Polpa Dentária/irrigação sanguínea , Polpa Dentária/citologia , Osteogênese/efeitos dos fármacos , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Células-Tronco/efeitos dos fármacos , Adolescente , Adulto , Compostos de Alumínio/toxicidade , Bismuto/toxicidade , Compostos de Cálcio/toxicidade , Sobrevivência Celular , Cimentos Dentários/toxicidade , Combinação de Medicamentos , Citometria de Fluxo , Humanos , Teste de Materiais , Óxidos/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Cimento de Óxido de Zinco e Eugenol/química , Cimento de Óxido de Zinco e Eugenol/toxicidade
10.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(2): 284-7, 2014 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-24743822

RESUMO

OBJECTIVE: To investigate influence of thermalcycling on the bonding durability of two one-step products [Adper Prompt (AP) and G-bond (GB)] and one two-step self-etching adhesive [Clearfil SE bond (SE)] with dentin in vitro. METHODS: Forty-two extracted human molars were selected. The superficial dentin was exposed by grinding off the enamel. The teeth were randomly distributed into six groups with varied bonding protocols. The adhesives were applied to the dentin surface. Composite crowns were built up, then the samples were cut longitudinally into sticks with 1.0 mm×1.0 mm bonding area [for microtensile bond strength (MTBS) testing] or 1.0 mm thick slabs (for nanoleakage observation). Bonding performance was evaluated with or without thermalcyling. For the MTBS testing, the strength values were statistically analysed using One-Way ANOVA. Four slabs in each group were observed for nanoleakage by SEM with a backscattered electron detector. RESULTS: Thermalcycling procedures affected MTBS. In the two one-step groups, the MTBS decreased significantly (P<0.05) after thermalcycling [AP group from (19.06±1.50) MPa to (12.62±2.10) MPa; GB group from (17.75±1.10) MPa to (6.24±0.42)MPa]. But in SE groups, MTBS did not significantly affect [(45.80±2.97) MPa compared with(40.60±5.76) MPa]. As a whole, one-step self-etching adhesives showed lower MTBS than two-step bonding system after aging.For AP and GB, continuous nanoleakage appearance was notable and more obvious than for SE. CONCLUSION: Thermalcycling can affect the bonding performance of self-etch adhesives including decrease of bond strength and nanoleakage pattern. one-step self-etch adhesives showed more obvious change compared with their two-step counterparts.


Assuntos
Adesivos , Colagem Dentária , Bis-Fenol A-Glicidil Metacrilato , Esmalte Dentário , Dentina , Humanos , Teste de Materiais , Metacrilatos , Organofosfatos , Cimentos de Resina , Resistência à Tração
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 46(1): 58-61, 2014 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-24535349

RESUMO

OBJECTIVE: To compare the clinical effectiveness of the two-step etch-and-rinse with the one-step self-etch adhesive in non-carious cervical lesions. METHODS: Fifty patients were selected, each with at least two wedge-shaped defects in the mouth. The paired defects were randomly bonded either with the two-step etch-and-rinse adhesive α or the one-step self-etch adhesive ß and then restored with resin composite. The treatment was carried out by one practitioner according to standard procedures. The evaluation was performed by another practitioner according to modified United States Public Health Service (USPHS) criteria at one week, six months and eighteen months after treatment. Chi-square test was used for statistical analysis. RESULTS: Fifty restorations were placed for each group. Forty-eight patients attended the six months recall, with two restorations loss for each group. Forty-four patients attended the eighteen months recall, with accumulative four restorations loss for adhesive α and six restorations loss for adhesive ß. The retention rate was 90.0% for group α and 86.4% for group ß. Marginal adaptation of three restorations in group α and five restorations in group ß were scored Bravo; while for marginal discoloration, two restorations in group α and three restorations in group ß were scored Bravo respectively. No secondary caries and post-operative sensitivity occurred for any of the restorations after eighteen months. No significant difference was detected between the groups for any evaluation criteria (P > 0.05). CONCLUSION: Within the observation period of this study, the two-step etch-and-rinse adhesive and the one-step self-etch adhesive showed similar clinical performance. The long term follow-up is still warranted.


Assuntos
Cimentos Dentários , Restauração Dentária Permanente , Condicionamento Ácido do Dente , Resinas Compostas , Humanos , Período Pós-Operatório , Colo do Dente/patologia
12.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 48(4): 244-7, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24021206

RESUMO

OBJECTIVE: To investigate the durability of self-etch adhesives bonded to dentin in vitro. METHODS: Forty-two extracted human molars were selected and occlusal dentin surfaces were exposed. The teeth were randomly distributed into three groups based on adhesives applied. The one-step self-etch adhesive B(Adper Prompt) and C(G-Bond) and two-step self-etch adhesive A (Clearfil SE bond) were used. After application of the adhesives to the dentin surfaces, composite crowns were built up, after 24 h water storage, the teeth were sectioned longitudinally into sticks (1.0 mm×1.0 mm bonding area) for microtensile testing or slabs (1 mm thick) for scanning electron microscopec (SEM) observation. Bonding strength (mTBS) and nano-leakage were evaluated immediately after cutting or after 6 months in water. The mTBS was analyzed using one-way ANOVA (SPSS 13.0). The nanoleakage was observed by SEM with a backscattered electron detector. RESULTS: Both adhesives and water storage time affected the mTBS. All adhesives showed decreased bond strength after six-month water aging [A dropped from (40.60 ± 5.76) MPa to (36.04 ± 3.15) MPa; B dropped from (19.06 ± 1.50) MPa to (11.19 ± 1.97) MPa; C dropped from (17.75 ± 1.10) MPa to (9.14 ± 1.15) MPa] (P < 0.05). B and C showed lower mTBS than A after aging (P < 0.05). Compared to A, nanoleakage was more obvious after aging for B and C. CONCLUSIONS: All self-etch adhesives tested were probably influenced by water aging, however, the two-step adhesive showed better durability than the one-step adhesives.


Assuntos
Adesivos , Colagem Dentária , Dentina , Humanos , Teste de Materiais , Resistência à Tração
13.
J Endod ; 39(10): 1218-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24041381

RESUMO

INTRODUCTION: The aim of this study was to compare the outcome of a root canal treatment with and without additional ultrasonic activation of the irrigant. METHODS: Single-rooted teeth with radiographic evidence of periapical bone loss were randomly assigned to 2 treatment groups. In both groups syringe irrigation was performed, and in one group the irrigant was also activated by ultrasound. Ten to 19 months after treatment, the teeth were examined by using periapical radiography (PA) and cone-beam computed tomography (CBCT). Area and volume of the periapical lesions were measured, and the outcome was presented in 4 categories: absence, reduction or enlargement of the radiolucency, or uncertain. Lesions were classified as reduced or enlarged when the change in size of the radiolucency was 20% or more. RESULTS: The recall rate was 82%, and 84 teeth were analyzed. CBCT detected significantly more post-treatment lesions than PA (P = .038), but the percentages of absence and reduction of the radiolucency together revealed by CBCT and PA were similar (P = .383). The CBCT results showed that absence of the radiolucency was observed in 16 of 84 teeth (19%) and reduction of the radiolucency in 61 of 84 teeth (72.6%), but there was no significant difference between the results of the 2 groups (P = .470). Absence and reduction of the radiolucency together were observed in the ultrasonic group in 39 of 41 teeth (95.1%) and in the syringe group in 38 of 43 teeth (88.4%). CONCLUSIONS: Root canal treatments with and without additional ultrasonic activation of the irrigant contributed equally to periapical healing.


Assuntos
Irrigantes do Canal Radicular/administração & dosagem , Preparo de Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Adolescente , Adulto , Idoso , Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/patologia , Ácido Edético/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Doenças Periapicais/diagnóstico por imagem , Doenças Periapicais/terapia , Radiografia Interproximal/métodos , Radiografia Dentária Digital/métodos , Materiais Restauradores do Canal Radicular/uso terapêutico , Preparo de Canal Radicular/instrumentação , Hipoclorito de Sódio/administração & dosagem , Seringas , Irrigação Terapêutica/instrumentação , Irrigação Terapêutica/métodos , Resultado do Tratamento , Ultrassom , Cicatrização/fisiologia , Adulto Jovem
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(5): 582-5, 2010 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-20957020

RESUMO

OBJECTIVE: To investigate the effect of filler content on the polymerization shrinkage of resins and to evaluate whether Acuvol is a simple and easy method in volumetric shrinkage measurement. METHODS: Six experimental resins with filler contents of 80%, 78%, 76%, 70%, 60%, and 50% were made. Three commercial resins were Syn D6 with 80% filler content, Syn Compact Nano with 74% filler content and Syn Flow with 55% filler content(using the mass fraction to express the filler content). Small semi-sphere samples of these composites were manually formed and light cured for 40 s using a quartz tungsten halogen unit at 650 mW/cm2 (n=10). The volumetric shrinkage was measured in both SVVR and MVVR modes using Acuvol. RESULTS: The volumetric shrinkage of the three commercial resins were: Syn Flow > Syn Compact Nano > Syn D6. The shrinkage values of the six experimental resins with different filler contents were: 50% > 60% > 70% > 76% > 78% > 80%. The negative correlation between filler content and volumetric shrinkage of commercial and experimental resins were strongly (-0.982 and -0.968 respectively, P<0.001). No significant difference between SVVR and MVVR modes (t=0.385, P>0.05). CONCLUSION: The present results support the view that filler content is one of the most important factors influencing polymerization shrinkage of composites. Acuvol provides an easy method for measuring polymerization shrinkage of composites. Both SVVR and MVVR modes of Acuvol give reproducible results.


Assuntos
Resinas Acrílicas/química , Resinas Compostas/química , Poliuretanos/química , Resinas Sintéticas/química , Gravação em Vídeo , Teste de Materiais/métodos , Polimerização
15.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(7): 426-8, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19031821

RESUMO

OBJECTIVE: To investigate the effects of application time and rubbing action of self-etching adhesives on resin-dentin bond strength and interface morphology in vitro. METHODS: Caries-free human third molars were wet ground to expose dentin surface. Three self-etching bonding agents were applied with varying application time and with/without rubbing. The microtensile bond strength and interface morphology were evaluated. RESULTS: When etching time was shortened, normal and prolonged, the bond strength was bonding agent 1 (Adper Prompt): (16.30 +/- 2.59), (23.13 +/- 2.56), (22.28 +/- 2.83) MPa, bonding agent 2 (Xeno III): (15.17 +/- 6.07), (34.50 +/- 3.64), (24.87 +/- 7.01) MPa, bonding agent 3 (Clearfil SE Bond): (29.92 +/- 3.32), (42.21 +/- 6.28), (41.07 +/- 3.93) MPa. When etching was applied with and without rubbing, the bond strength was bonding agent 1 (23.13 +/- 2.56), (12.53 +/- 3.73) MPa, bonding agent 2 (23.98 +/- 3.86), (34.50 +/- 3.64) MPa, bonding agent 3 (48.37 +/- 4.95), (42.21 +/- 6.28) MPa. CONCLUSIONS: Shortening application time decreased bond strength of self-etching adhesives, while prolonging application time did not increase bond strength of self-etching adhesives. Not all self-etching adhesives applied with rubbing showed increased bond strength to dentin, which is product-dependent. Manufactures' instructions should be followed to achieve optimum bonding.


Assuntos
Condicionamento Ácido do Dente/métodos , Colagem Dentária/métodos , Cimentos Dentários , Cimentos Dentários/classificação , Humanos , Dente Serotino
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 42(4): 240-1, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17683675

RESUMO

OBJECTIVE: To evaluate the microtensile bond strength of one-step self-etching adhesives to dentin in vitro. METHODS: Three commercially available one-step self-etching bonding systems (group A: Adper Prompt, group B: Clearfil S(3) Bond, group C: Xeno III) were compared with two-step self-etching adhesive (group D: Clearfil SE Bond) in this study. The microtensile bond strength was determined with microtensile tester and the fractured bonding surfaces were observed under stereomicroscope and scanning electronic microscope (SEM). The mean bond strengths were analyzed using one-way ANOVA test (P < 0.05). RESULTS: Mean microtensile bond strengths of group C, B, A and D were (34.59 +/- 3.46), (30.46 +/- 3.82), (23.36 +/- 2.55) and (45.06 +/- 5.29) MPa, respectively. Group D showed the highest bond strength (P < 0.01). CONCLUSIONS: Two-step self-etching adhesive had a higher bond strength than one-step self-etching adhesive systems, although all of them can satisfy the clinical requirements.


Assuntos
Resinas Compostas , Adesivos Dentinários , Bis-Fenol A-Glicidil Metacrilato , Humanos , Organofosfatos , Cimentos de Resina , Resistência à Tração
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