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1.
Int Endod J ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34516682

RESUMO

AIM: To evaluate the impact of various predictors on the outcome of root canal retreatment in symptomatic mandibular first molars with periapical lesions after a minimum of 2 years. METHODOLOGY: One hundred and twenty previously root canal treated symptomatic mandibular first molars with periapical lesions which were diagnosed as symptomatic apical periodontitis or acute apical abscess with localized intraoral swelling were included. Root canal retreatment was performed by an experienced endodontist using a standardized treatment protocol. The teeth were followed up clinically and radiographically and the radiographic outcome was assessed using a modified periapical index scale (PAI). The cumulative success proportion and the influence of predictors on the outcome of the root canal retreatment were analysed using Kaplan-Meier analyses and log-rank tests, and the hazard ratios for the predictors were also investigated using Univariate Cox Proportional Hazard regression analysis at a significance level of 5%. RESULTS: Of the 120 teeth, 103 teeth were re-examined with an 85% recall rate. The cumulative success rate was 88% in which 64% were healed and 24% were healing, and failure rate was recorded as 12%. None of the preoperative predictors, including age, gender, soft tissue tenderness, intraoral swelling, size of the lesion, PAI score, apical level and density of root canal filling before root canal retreatment, nor intraoperative predictors, such as active exudate drainage, density of root canal filling after root canal retreatment and restoration type had an influence on the outcome of root canal retreatment (p > .05). The only factor that significantly reduced the success rate of root canal retreatment was the apical level of the root canal filling; when it was more than 2 mm short of the radiographic apex in teeth where apical patency was not established, the success was significantly lower (p = .023). CONCLUSIONS: Root canal retreatment in symptomatic mandibular first molars with periapical lesions resulted in a success rate of 88%. None of the predictors had a significant influence on the outcome, except for the apical level of the root canal filling after root canal retreatment with short root fillings being associated with significantly more post-treatment endodontic disease.

2.
Nanoscale ; 13(35): 14879-14899, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533177

RESUMO

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag2S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codelivery of 5FU. Delivery of ALA via covalent linkages was also effective for PDT, but required a longer incubation time for the release of ALA in therapeutic doses. Phototoxicity was correlated with high levels of reactive oxygen species (ROS) and apoptotic/necrotic cell death. Hence, both AS-2MPA-ALA-Cet based PDT and AS-2MPA-ALA-Cet-5FU based chemo/PDT combination therapy coupled with strong NIR tracking of the nanoparticles demonstrate an exceptional therapeutic effect on CRC cells and excellent potential for synergistic multistage tumour targeting therapy.


Assuntos
Neoplasias Colorretais , Fotoquimioterapia , Pontos Quânticos , Ácido Aminolevulínico/farmacologia , Linhagem Celular Tumoral , Cetuximab/farmacologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Humanos , Imagem Óptica , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas
3.
Aust Endod J ; 2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34278665

RESUMO

This study aimed to evaluate the effect of multi-file rotary (Protaper Universal) and reciprocating single-file (Reciproc Blue) root canal preparation techniques on the occurrence of postoperative pain in asymptomatic mandibular molar teeth with large periapical lesions in single-visit root canal treatment (RCT). A hundred and twenty teeth were randomly assigned to two groups: Protaper Universal (PTU) or Reciproc Blue (RB) instruments. Postoperative pain at 6, 12, 24, 48, 72 h and 7 days after obturation was measured. Mann-Whitney U-test was performed to compare the pain scores between the groups and to assess the relation of pain with patients' age and gender. Spearman's rank correlation was utilized to correlate the pain intensity and analgesic intake at different time points. There was no significant difference between the instrumentation techniques regarding postoperative pain at any time points evaluated (P > 0.05). There was a correlation between analgesic intake and intensity of pain (P < 0.05). No statistically significant difference was found among the groups assessed in the study in terms of analgesic intake (P > 0.05).

4.
J Biomed Mater Res A ; 108(10): 2100-2110, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32319210

RESUMO

Novel phosphonic acid-functionalized poly(amido amine) (PAA) macromers are synthesized through aza-Michael addition of 2-aminoethyl phosphonic acid or its mixture with 5-amino-1-pentanol at different ratios onto N,N'-methylene bis(acrylamide) to control the amount of phosphonic acid functionality. The macromers were homo- and copolymerized with 2-hydroxyethyl methacrylate at different ratios to obtain hydrogels with various hydrophilicities. The hydrogels' swelling, biodegradation and mineralization properties were evaluated. The swelling and degradation rates of the gels can be tuned by the chemical structure of PAA macromer precursors as well as pH and CaCl2 pre-treatment. The hydrogels show composition-dependent mineralization in SBF and 5xSBF, as evidenced from Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX) analyses. The degradation products of the hydrogels have no effect on U-2 OS, Saos-2 and NIH 3T3 cells, suggesting their cytocompatibility. Overall, these materials have potential to be used as nontoxic degradable biomaterials.

5.
Microsc Res Tech ; 83(7): 790-794, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32170795

RESUMO

The aim of this study was to evaluate the cyclic fatigue resistance of Dia-X, WaveOne Gold and One Curve files in a water bath at intracanal temperature (35°C). Thirty-nine instruments Dia-X, WaveOne Gold, and One Curve systems (n = 13) were tested in an artificial canal with a curvature angle of 60° and a radius of 3 mm. A water bath setup at a temperature of 35°C was used to simulate the intracanal temperature and time to fracture (TTF) as seconds was recorded. The mean data were analyzed statistically using one-way ANOVA, and post hoc Tukey test (p = .05). The fractured surface of the instruments was examined with scanning electron microscopy (SEM) and chemical composition of the instruments were investigated with energy dispersive X-ray spectroscopy (EDS). Statistically significant differences were detected in TTF values of all the systems as follows: One Curve > WaveOne Gold > Dia-X (p < .05). One Curve instruments demonstrated the highest TTF values in all the tested instruments. The EDS microanalysis revealed similar NiTi composition of on the surface of One Curve, WaveOne Gold, and Dia-X instruments. The novel manufacturing process, including C-wire heat treatment and the variable cross-section of the One Curve files, could be the main factors affecting the fatigue life of the instruments.

6.
J Endod ; 46(2): 277-282, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812359

RESUMO

INTRODUCTION: Root canal retreatment procedure may reduce the mechanical resistance of nickel-titanium instruments and increase the frequency of instrument fracture. The aim of the present study was to evaluate the effect of multiuse of Reciproc Blue R25 instruments on cyclic fatigue resistance during retreatment procedure in mandibular molar teeth. METHODS: Forty-eight Reciproc Blue R25 files were included in the study. In control group, 12 new Reciproc Blue R25 instruments were subjected to cyclic fatigue test by using a stainless steel artificial canal with a 90° angle and 3-mm radius of curvatures. In experimental groups, Reciproc Blue R25 files (n = 12) were used to remove the root canal filling (RCF) material of 1, 2, and 3 molar teeth, respectively. Then cyclic fatigue tests of these 36 instruments were performed. The number of cycles to fracture (NCF) and the length of the fractured fragment were calculated for each instrument. Working time for retreatment procedures was determined in seconds with a digital chronometer. The data were analyzed by using one-way analysis of variance followed by post hoc Tukey test and mixed-effect analysis (P = .05). RESULTS: No significant difference was found between NCF values of new and first time used files (P > .05), but NCF values of new and first time used files were significantly higher than those of second and third time used files (P < .05). The second and third time used files revealed no difference (P > .05). As the number of uses increased, the average time for retreatment procedure statistically extended (P < .05). CONCLUSIONS: Reciproc Blue R25 instrument can be used to remove RCF material of 2 molar teeth. However, because of its decreased NCF values, multiple use over 2 molars may not be suggested.


Assuntos
Instrumentos Odontológicos , Preparo de Canal Radicular , Desenho de Equipamento , Falha de Equipamento , Teste de Materiais , Retratamento , Titânio
7.
J Mater Chem B ; 7(46): 7363-7376, 2019 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-31696188

RESUMO

Targeted drug delivery systems that combine imaging and therapeutic functions in a single structure have become very popular in nanomedicine. Near-infrared (NIR) emitting Ag2S quantum dots (QDs) are excellent candidates for this task. Here, we have developed PEGylated Ag2S QDs functionalized with Cetuximab (Cet) antibody and loaded with an anticancer drug, 5-fluorouracil (5FU). These theranostic QDs were used for targeted NIR imaging and treatment of lung cancer using low (H1299) and high (A549) Epidermal Growth Factor Receptor (EGFR) overexpressing cell lines. The Cet conjugated QDs effectively and selectively delivered 5FU to A549 cells and provided significantly enhanced cell death associated with apoptosis. Interestingly, while treatment of cells with free 5FU activated autophagy, a cellular mechanism conferring resistance to cell death, these EGFR targeting multimodal QDs significantly overcame drug resistance compared to 5FU treatment alone. The improved therapeutic outcome of 5FU delivered to A549 cells by Cet conjugated Ag2S QDs is suggested as the synergistic outcome of enhanced receptor mediated uptake of nanoparticles, and hence the drug, coupled with suppressed autophagy even in the absence of addition of an autophagy suppressor.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/administração & dosagem , Neoplasias Pulmonares/metabolismo , Compostos de Prata/química , Células A549 , Autofagia , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetuximab/administração & dosagem , Receptores ErbB/genética , Humanos , Imidazóis/química , Neoplasias Pulmonares/tratamento farmacológico , Polietilenoglicóis/química , Pontos Quânticos , Nanomedicina Teranóstica
8.
Nanomedicine (Lond) ; 14(8): 969-987, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30917096

RESUMO

AIM: N-acetyl-L-cysteine (NAC) is a free radical scavenger. We developed NAC-coated Ag2S (NAC-Ag2S) quantum dot (QD) as an optical imaging and therapeutic agent. MATERIALS & METHODS: QDs were synthesized in water. Their optical imaging potential and toxicity were studied in vitro. RESULTS: NAC-Ag2S QDs have strong emission, that is tunable between 748 and 840 nm, and are stable in biologically relevant media. QDs showed significant differences both in cell internalization and toxicity in vitro. QDs were quite toxic to breast and cervical cancer cells but not to lung derived cells despite the higher uptake. NAC-Ag2S reduces reactive oxygen species (ROS) but causes cell death via DNA damage and apoptosis. CONCLUSION: NAC-Ag2S QDs are stable and strong signal-generating theranostic agents offering selective therapeutic effects.


Assuntos
Acetilcisteína/química , Antineoplásicos/química , Sequestradores de Radicais Livres/química , Substâncias Luminescentes/química , Pontos Quânticos/química , Compostos de Prata/química , Apoptose/efeitos dos fármacos , Transporte Biológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Raios Infravermelhos , Luminescência , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
9.
J Endod ; 44(8): 1228-1236, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29935875

RESUMO

INTRODUCTION: The concept of maintaining apical patency (AP) is a controversial issue in endodontics. The primary objectives of this systematic review of randomized controlled trials (RCTs) were to determine the influence of maintaining AP during instrumentation on postoperative pain severity and the prevalence of flare-ups. A second objective was to assess the effect of maintaining AP on the use of analgesics. METHODS: RCTs and controlled clinical trials were searched for in MEDLINE (Ovid), Embase (Ovid), and the Cochrane Library. Four reviewers independently screened all identified articles for eligibility. The included studies were assessed for bias using the Cochrane Risk of Bias Tool. The Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the quality of the body of evidence. Because of the considerable heterogeneity of the studies, a meta-analysis was not possible. Therefore, the results were analyzed narratively. RESULTS: Five RCTs that included a total of 848 patients were found eligible and included in the review. An assessment of the risk of bias in the included studies provided results that classified the studies as showing a low risk (n = 1), high risk (n = 1), or unclear risk (n = 3) of bias. The available evidence indicated that maintaining AP (1) did not increase postoperative pain in teeth with nonvital pulp, (2) did not increase postoperative pain in teeth with vital pulp, and (3) did not cause (0%) flare-ups. The available evidence also indicated that maintaining AP did not increase analgesic use. The available evidence indicated that maintaining AP did not increase postoperative pain when a single-visit or 2-visit root canal treatment approach was used. CONCLUSIONS: In light of the current evidence, maintaining AP does not increase postoperative pain in teeth with vital/nonvital pulp when compared with nonapical patency (low to moderate quality evidence). Furthermore, maintaining AP did not cause flare-ups (low evidence) and did not increase analgesic use (moderate evidence).


Assuntos
Dor Pós-Operatória/etiologia , Tratamento do Canal Radicular/métodos , Ápice Dentário/cirurgia , Analgésicos/uso terapêutico , Humanos , Dor Pós-Operatória/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Tratamento do Canal Radicular/efeitos adversos , Tratamento do Canal Radicular/instrumentação
10.
J Endod ; 42(2): 206-10, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26686053

RESUMO

INTRODUCTION: The aim of this study was to compare the outcome of root canal treatment using either Thermafil (TF; Dentsply Maillefer, Ballaigues, Switzerland) or the cold lateral condensation (CLC) obturation technique in teeth with periapical lesions and to investigate the influence on postoperative pain and treatment outcomes. METHODS: After standardized root canal preparation technique, 112 teeth were obturated with either the TF or the CLC technique during 2 sessions by single operator. Postoperative pain, obturation length, and treatment outcomes were recorded. The teeth were reviewed clinically and radiographically for 2 years. RESULTS: Although there were no significant differences between the techniques in the incidence of postoperative pain at 24 hours (P > .05), the incidence of pain was significantly higher in the TF group than in the CLC group at 48 hours (P < .05). During the 2-year follow-up period, there was no statistically significant difference in the success rate of the teeth treated with TF (96.4%) in comparison with those treated with CLC (98.2%) (P > .05). CONCLUSIONS: In this study, the outcome of the root canal treatment of teeth using the TF and CLC techniques revealed that these techniques are useful for root canal obturation.


Assuntos
Guta-Percha , Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Obturação do Canal Radicular/efeitos adversos , Preparo de Canal Radicular/efeitos adversos , Tratamento do Canal Radicular/efeitos adversos , Temperatura , Resultado do Tratamento , Adulto Jovem
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