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1.
BMC Oral Health ; 23(1): 45, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36698104

RESUMO

BACKGROUND: Dental curriculums require regular revision to stay up to date in scientifical and societal fields. Senior dental students are among the main stakeholders of such curriculums. The present study investigated the opinions of Iranian senior dental students regarding the adequacy of their dentistry program and the national dental curriculum in training a competent dentist, the program's content, and its structure. METHODS: A previously designed and validated questionnaire on the opinion of senior dental students regarding curriculum adequacy was sent to a representative in each of the country's dental schools. Before the COVID pandemic terminated data collection, a total of 16 schools (438 students) managed to respond (37%). The questionnaire asked the students to assess the adequacy of the training received in curriculum's theoretical and practical competencies with the help of a five-point Likert scale that ranged from "Completely inadequate" to "Completely adequate". It also questioned them on its teaching methods and intensity. SPSS software version 24 and Chi-square test served for statistical analysis. RESULTS: In total, the study has 438 participants, 245 female and 193 male. Significant sex differences were spotted in the responses concerning both theoretical and practical training. Regarding general training adequacy, 50 (22.6%) female students and 50 male ones (30.7%), P = 0.08 agreed that the program was acceptable. The numbers for students of old (more than 15 years of activity) and new schools were 47 (21.7%) and 53 (31.7%), respectively (P = 0.03). Nearly one-third deemed the teaching methods appropriate. Regarding the duration of curriculum phases, 33 students (8.3%) believed that basic science required extension, while 108 (28.6%) and 266 (69.1%) reported such need for pre-clinical and clinical phases. The school's years of activity emerged as significant, as 38.1% of students from new schools versus 21.7% of those from old ones deemed the extension of pre-clinical phase necessary (P < 0.001). CONCLUSION: A significant number of Iranian senior dental students found the undergraduate dental curriculum inadequate regarding competencies, content, and teaching. Further investigations will determine whether it's the curriculum or its implementation that warrants revision.


Assuntos
COVID-19 , Estudantes de Odontologia , Feminino , Humanos , Masculino , Currículo , Retroalimentação , Irã (Geográfico) , Inquéritos e Questionários , Faculdades de Odontologia
2.
Clin Oral Investig ; 25(8): 4817-4824, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33751220

RESUMO

OBJECTIVES: Diagnosing cavitated proximal lesions is important for therapeutic decisions. This clinical study aimed to determine the validity of laser fluorescence (LF) and near-infrared reflection (NIRR) techniques for detecting early proximal cavities. MATERIALS AND METHODS: The study included 43 proximal surfaces in 15 females who had limited radiolucent lesions in their bitewing radiographs. The approximal areas of interest were assessed by DIAGNOdent Pen (LF) and the Proxi interchangeable head of VistaCam iX intraoral camera (NIRR). Finally, orthodontic separators were placed in the contact points to provide enough space between the teeth. The sensitivity, specificity, and accuracy of diagnosing cavitated proximal surfaces were calculated for LF and NIRR against direct visual and tactile examination as the reference standard. RESULTS: On the basis of the reference standard, 34 surfaces (79.1%) were not cavitated, whereas 9 surfaces (20.9%) were cavitated and in need of restoration. The sensitivity, specificity, and accuracy of LF were 44.4%, 61.8%, and 58%, and those of NIRR were 88.9%, 14.7%, and 30%, respectively. CONCLUSIONS: The VistaCam iX Proxi was more sensitive and DIAGNOdent Pen was more specific in detection of proximal cavities. However, none of the techniques was accurate enough to be recommended as a sole approach for proximal caries detection. CLINICAL RELEVANCE: LF showed an overall superior diagnostic performance to NIRR for diagnosing proximal cavitation in permanent posterior teeth. Within the limitations of this study, neither VistaCam iX Proxi nor DIAGNOdent Pen could be considered a suitable device for diagnosing proximal cavities.


Assuntos
Cárie Dentária , Cárie Dentária/diagnóstico por imagem , Feminino , Fluorescência , Humanos , Lasers , Radiografia Interproximal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Microb Pathog ; 98: 112-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27354208

RESUMO

The objective of this study was to determine the correlation between Enterobacter cloacae complex subspecies and clusters involved in UTI infections and specific pulsotypes, and to assess the contribution of major curli biogenesis genes (csgD, csgA) expression level to pathogenesis of clusters and genotypes. Based on the PFGE analysis, 37 different profiles were observed among which 8 profiles were common types. Real time PCR of csgD and csgA genes of 50 E. cloacae complex in relation to PFGE and hsp60 genotypes showed that all the genetic clusters are not equally involved in pathogenesis of urinary tract infections. It was elucidated in this study that isolates with common PFGE genotypes belonged to identical hsp60 clusters, and the foremost clusters (VI, III, and V) mainly comprised within PFGE common types. In our study, no significant correlation was detected between the specific hsp60 clusters or PFGE genotypes and the expression level of csgD and csgA genes (P-value > 0.05). This is the first study describing that unequivalent contribution of E. cloacae genotypes and clusters in pathogenesis of UTI, is not owing to varied curli biogenesis expression potential. The PFGE genotyping showed more discriminatory power than hsp60 genotyping for epidemiological studies and source tracking purpose.


Assuntos
Proteínas de Bactérias/biossíntese , Chaperonina 60/biossíntese , Eletroforese em Gel de Campo Pulsado , Enterobacter cloacae/classificação , Enterobacter cloacae/metabolismo , Regulação Bacteriana da Expressão Gênica , Genótipo , Análise por Conglomerados , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Perfilação da Expressão Gênica , Variação Genética , Humanos , Tipagem Molecular , Infecções Urinárias/microbiologia
4.
Skeletal Radiol ; 43(12): 1755-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25022808

RESUMO

Glomus tumors are predominantly benign neoplasms accounting for less than 2% of all soft tissue tumors. While generally solitary, multiple lesions have been reported in approximately 10% of cases. Glomus tumors are typically under 1 cm in dimension accompanied by the classic triad of symptoms: debilitating pain, pinpoint tenderness, and hypersensitivity to cold temperatures. Excisional therapy is the accepted standard of care, however, past reports of non-invasive treatments for multiple glomangiomata variant tumors include laser therapy, irradiation, and sclerotherapy with STS and hypertonic saline. We present a case of a patient with multiple subcutaneous and intramuscular, lower-extremity benign solid glomus tumors treated successfully utilizing ethanol ablation, which has not been previously reported. This minimally invasive treatment allowed for control of symptoms from a benign condition previously requiring multiple invasive surgeries.


Assuntos
Técnicas de Ablação/métodos , Etanol/uso terapêutico , Tumor Glômico/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Diagnóstico Diferencial , Feminino , Tumor Glômico/diagnóstico , Humanos , Perna (Membro)/diagnóstico por imagem , Perna (Membro)/patologia , Perna (Membro)/cirurgia , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Neoplasias de Tecidos Moles/diagnóstico , Solventes/uso terapêutico , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler em Cores/métodos
5.
J Contemp Dent Pract ; 15(6): 730-4, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25825098

RESUMO

OBJECTIVES: Psychoactive drugs are responsible for pathological changes in the mouth including dental caries, which most troublesome. The aim of the present study was to evaluate the effect of heroin on several salivary factors which are involved in the oral health and their changes after methadone maintenance therapy (MMT). MATERIALS AND METHODS: Forty patients with heroin abuse history, who referred to Imam Reza Hospital for MMT were included. Saliva sampling was carried out two times; at the first visit (time 1) and repeated 1 month after MMT (time 2). The saliva was analyzed immediately to evaluate the total volume, Ph, CPR, the Uric acid concentration, nitric oxide and antioxidant capacity. RESULTS: The mean values for saliva volume, pH, CRP, Uric acid, antioxidant and nitric oxide were 0.38 ± 0.14, 7.63 ± 1.22, 5.2 ± 2.3, 1.47 ± 0.8, 0.80 ± 0.23, and 0.26 ± 0.03, respectively at first visit and 0.34 ± 0.22, 7.37 ± 1.01, 6.1 ± 2.6, 2.18 ± 0.9, 0.74 ± 0.3 and 0.29 ± 0.08 after 1 month of MMT. These values are below the normal ranges; however, there was no significant difference between two times in term of saliva volume, pH and saliva component (p > 0.05). CONCLUSION: Heroin addiction changed the effective salivary factors and therefore could negatively contribute to oral health. These factors were not return to the normal range after 1 month of MMT. Physicians should be informed about focusing on oral health in patients under MMT.


Assuntos
Dependência de Heroína/metabolismo , Heroína/efeitos adversos , Metadona/uso terapêutico , Entorpecentes/efeitos adversos , Tratamento de Substituição de Opiáceos , Saliva/efeitos dos fármacos , Adolescente , Adulto , Antioxidantes/análise , Proteína C-Reativa/análise , Feminino , Seguimentos , Dependência de Heroína/reabilitação , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/análise , Peroxidase/análise , Peroxidase/efeitos dos fármacos , Ácido Úrico/análise , Adulto Jovem
6.
Iran J Parasitol ; 18(1): 38-47, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37197073

RESUMO

Background: Due to the opportunism character of Acanthamoeba, the presence of this parasite in the thermal water of recreational baths and hospital environments can be a risk to the health of staff, patients and others. The aim of this study was to investigate the distribution of potentially pathogenic Acanthamoeba genotypes isolated from the hospital environment and the thermal water of recreational baths in Markazi Province, central Iran. Methods: Overall, 180 samples including thermal water from recreational baths in Mahallat City and dust, soil and water from different hospitals of Arak, Farahan and Komijan cities, central Iran were collected. The presence of Acanthamoeba was investigated using microscopic examination and molecular methods. The PCR and sequencing was performed based on a specific 18S fragment of ribosomal DNA. Results: Based on the microscopic survey, totally 134 positive samples were detected including 35% in thermal water samples and 44.7% in hospital samples. In molecular analysis, 53.5% of the samples were identified as Acanthamoeba and 46.7% as Protacanthamoeba bohemica. The genotypes were detected as T4 (33.3%), T2 (10%), T11 (6.7%), and T5 (3.3%). Conclusion: The T4 was the most common genotype found in hospitals sampling sites while the T2 genotype and P. bohemica were detected in thermal water sampling sites.

7.
J Contemp Dent Pract ; 13(4): 515-20, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23151702

RESUMO

AIM: The objective of this study was to determine the association between DIAGNOdent laser and caries detector dye in detection of the remaining caries in restorative cavities. MATERIALS AND METHODS: The sample consisted of 100 cavities prepared in patients referring to the Department of Restorative Dentistry of Mashhad Dental School. After confirming caries absence by tactile examination, the presence of any residual caries was determined by a laser fluorescence (LF) device (DIAGNOdent Pen) and then by caries detector dye. The data were analyzed through McNemar test. RESULTS: When the cut off value was considered as ≥13, both DIAGNOdent Pen and caries detector dye found 54 cavities as without caries and 12 cavities as carious. There were 32 teeth diagnosed as decayed only by the dye and two cases that were diagnosed as having residual caries only by the DIAGNOdent. The McNemar test revealed a significant difference in the diagnosis of residual caries between the two methods (p < 0.05), as well as significant differences between each method and tactile examination (p < 0.05). When the cut off value was set at ≥25, no significant difference was found between laser fluorescence and tactile examination in residual caries detection (p > 0.05). CONCLUSION: Both DIAGNOdent Pen and caries detector dye can be considered as adjuncts for detecting residual caries in prepared cavities. However, the use of laser fluorescence device can provide results that are more consistent with tactile examination, while relying on caries detector dye may result in excessive removal of tooth tissue, and thus increase the risk of pulpal exposure. CLINICAL SIGNIFICANCE: Incomparision with caries detector dye, Residual caries detection by DIAGNOdent Pen is more consistent with tactile examination.


Assuntos
Corantes , Cárie Dentária/diagnóstico , Lasers , Adulto , Preparo da Cavidade Dentária , Fluorescência , Humanos , Pessoa de Meia-Idade , Propilenoglicóis , Rodaminas , Estatísticas não Paramétricas
8.
Protein Pept Lett ; 29(1): 102-109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34825862

RESUMO

OBJECTIVE: Oral infections and dental caries are considered serious health problems. Therefore, searching for new agents with antimicrobial properties seems to be crucial. This study aimed to evaluate the antimicrobial activity of the recombinant Thrombocidin-1 [TC-1] peptide on some oral pathogens. Also, the cytotoxicity of this peptide on human gingival fibroblast cells was investigated. METHODS: In this study, Pichia pastoris was used for the expression of recombinant TC-1. The microbroth dilution method was used to determine the minimum inhibitory concentration [MIC] and minimum bacterial concentration [MBC]. It tested against four main oral pathogens; Streptococcus mutans, Streptococcus salivarius, Streptococcus oralis, and Enterococcus faecalis. Moreover, the cytotoxicity analysis was done on gingival fibroblast cells by the MTT method. The data were analyzed using a two-way analysis of variance [ANOVA] and Tukey's HSD tests. RESULTS: The most bactericidal effect of TC-1 was against S. salivarius, the highest bacteriostatic effect was against S. salivarius, and S. oralis had the lowest MIC value of 1.512 µg/ml. The Thrombocidin- 1 peptide showed lower antibacterial properties against E. faecalis compared with CHX, unlike the stronger antimicrobial effect on examined streptococci. According to cytotoxicity examination, no concentration of TC-1 presented over 50% growth inhibition [IC50] of the fibroblasts cells. CONCLUSION: Based on antimicrobial tests and cytotoxicity results, the Thrombocidin-1 peptide may be useful as a safe antibacterial agent against some oral pathogens in dental materials.


Assuntos
Anti-Infecciosos , Cárie Dentária , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Peptídeos Antimicrobianos , Cárie Dentária/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Saccharomycetales , Streptococcus mutans/genética
9.
Curr Drug Discov Technol ; 18(6): e130921187870, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33183206

RESUMO

OBJECTIVES: The present study was conducted to evaluate the antimicrobial effects of the recombinant chimer present in the lactoferrampin-lactoferricin [LFA-LFC] derived from the camel milk on some oral bacteria responsible for dental caries and endodontic failures. METHODS AND MATERIAL: The antimicrobial activity was assessed on the Streptococcus mutans [ATCC 35668], Streptococcus salivarius [ATCC 9222], Streptococcus oralis [ATCC 35037], and Enterococcus faecalis [ATCC 29212], using the microbroth dilution method. The cytotoxicity analysis was done through the MTT method on the human gingival fibroblasts. The data were reported using the descriptive methods and were analyzed by the one-way analysis of variance (ANOVA) and Tukey HSD test. RESULTS: Results showed that the chimeric peptide had the highest bacteriostatic effect on S. salivarius with the lowest minimum inhibitory concentration value of 1.22 µg/Ml. Also, LFA-LFC chimer was more effective against S. mutans and S. salivarius compared to using 0.2% chlorhexidine mouthwash. The minimum bactericidal concentration analysis showed the most bactericidal effect against S. mutans [1.256 µg/mL]. In spite of the greater antibacterial effect on the evaluated streptococci, this peptide showed lower bacteriostatic and bactericidal properties against E. faecalis compared to the chlorhexidine. Based on cytotoxicity assay, over 50% of the cells were viable in all the evaluation times, demonstrating the biocompatibility of the peptide. CONCLUSION: The LFA-LFC chimer revealed comparable or even more effective antibacterial properties compared to the chlorhexidine mouthwash against the caries-inducing bacteria with no toxicity on the human gingival fibroblast cells. So, this peptide can be used as a safe alternative to chlorhexidine and other chemicals in dental applications for the prevention and management of dental caries.


Assuntos
Camelus , Cárie Dentária , Animais , Antibacterianos/toxicidade , Peptídeos Antimicrobianos , Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Lactoferrina , Testes de Sensibilidade Microbiana , Leite , Fragmentos de Peptídeos , Streptococcus mutans
10.
Quintessence Int ; 52(7): 596-605, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33749220

RESUMO

OBJECTIVE: Bleaching sensitivity (BS) is the most common adverse effect of tooth bleaching treatments. This study evaluated the effect of adding 1% sodium hexametaphosphate (SHMP) on BS and the whitening effectiveness of a bleaching gel. METHOD AND MATERIALS: Two maxillary quadrants from 26 patients were randomly assigned to the experimental and control groups in a split-mouth design. In the control group the at-home bleaching gel containing 3% hydrogen peroxide, and in the experimental quadrant the same gel with 1% SHMP, were applied in individual trays for 6 hours per night for 2 weeks. The patients' sensitivity to cold and touch as well as spontaneous sensitivity were recorded based on a visual analog scale (VAS). Changes in shade guide units (ΔSGU) and ΔE were measured using a spectrophotometer. Data were analyzed using the Kolmogorov-Smirnov, Mann-Whitney U, Wilcoxon signed-rank test, and independent sample t test. RESULTS: Twenty-four patients completed the study. After 2 weeks, the sensitivity to cold and touch was significantly lower in the intervention group compared to the control (P = .015 and P = .039, respectively). The spontaneous sensitivity revealed no significant alteration between these two groups and during the bleaching period in each group (P > .050). Regarding both color measurements, the bleaching effectiveness in both groups was comparable, with no noticeable difference (P > .050). CONCLUSION: The application of 1% SHMP was able to reduce the BS with no detrimental effect on the at-home bleaching effectiveness. (Quintessence Int 2021;52:596-605; doi: 10.3290/j.qi.b1098303).


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Sensibilidade da Dentina/induzido quimicamente , Sensibilidade da Dentina/prevenção & controle , Humanos , Peróxido de Hidrogênio , Fosfatos , Clareamento Dental/efeitos adversos , Clareadores Dentários/efeitos adversos , Resultado do Tratamento
11.
J Clin Exp Dent ; 12(6): e523-e532, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32665810

RESUMO

BACKGROUND: This study was conducted aimed at evaluating the antibacterial property of the recombinant peptide of bacteriocin entrocin P (EnP), the essential oil of Cuminum cyminum, and the extract of Ferulago angulata on some oral pathogens. Besides, the cytotoxicity of EnP was evaluated. MATERIAL AND METHODS: The antimicrobial property was tested on streptococcus mutans (ATCC 35668), streptococcus salivarius (ATCC 9222), streptococcus oralis (ATCC 35037), and Enterococcus faecalis (ATCC 29212), using the microbroth dilution method. The 0.2% Chlorhexidin (CHX) mouthwash was used as the control group. Besides, the cytotoxicity analysis was done on gingival fibroblasts by the MTT colorimetric method. The data were reported using descriptive methods, and analyzed by one-way ANOVA, and Tukey's HSD test. RESULTS: The strongest bacteriostatic and bactericidal effects of C. cyminum and F. angulata were observed for S.mutans and S. oralis, respectively (with the MIC and MBC value being 62.5 µg/mL). The antibacterial properties of EnP were comparable to those of CHX, being several times stronger than medicinal plants (1-14 µg/mL). Based on the cytotoxicity evaluation, there was no statistically significant difference observed between the cytotoxicity of the control group and that of Enp for three evaluations, except after 72 hours when the cell viability at the concentration of 3.75 µg/ml was significantly lower than that of the control group (P=0.05). However, no concentration of EnP was observed to be over 50% of the growth inhibition (IC50) of the fibroblasts for the three evaluations. CONCLUSIONS: EnP could be utilized in dental materials as a natural and safe antimicrobial agent against oral streptococci and E. faecalis, being as effective as CHX mouthwash. Key words:Antimicrobial peptide, Bacteriocin Entrocin P, Chlorhexidine, Cuminum cyminum, Enterococcus faecalis, Ferulago angulata.

12.
Rep Biochem Mol Biol ; 9(3): 257-263, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33649718

RESUMO

BACKGROUND: Campylobacter spp. are the main cause of human gastroenteritis. The 16SrRNA sequencing is one of fast molecualr method to detect this fastidious. In this study, we compared the sequencing of 16srRNA genewith four housekeeping genestodetect Campylobacter spp. in patients with diarrhea and healthy people. METHODS: 60 samples of Campylobacter DNA extracted from stool samples of 30 patients with diarrhea and 30 healthy people were used. In order to detect Campylobacter, we designed primers for proliferation of 16SrRNA, cadF, dnaJ, slyD , and rpoA genes using Primer 3, Mega 4.0 and Blast software. Then the PCR products were sequenced using ABI system. RESULTS: The sequencing showed concordance of PCR-products with deposited sequences in the Gene Bank. Among diarrhea patients, 53.3% of samples were significantly (p< 0.05) positive for slyD and cadF genes and 50% of samples were positive using 16SrRNA, rpoA, and dnaJ genes by PCR assay. The average of sensitivity and specificity were found 53.33% and 83.33%, respectively. CONCLUSION: Due to various copies of repeated sequences of 16SrRNA gene, analyzing its amplicons on electrophoresis may be more difficult than the slyD and cadF genes. According to our results, among the 5 studied genes; the highest detection rate was related to slyD and cadF genes. Although, dnaJ and rpoA genes,instead of 16SrRNA gene, can be considered as appropriate genes for molecular detection of Campylobacter bacteria.

13.
Swiss Dent J ; 130(6): 493-501, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32512985

RESUMO

This study aimed to evaluate the efficacy and complications of several bleaching methods in patients with discolored teeth after orthodontic treatment. This randomized clinical trial involved 60 volunteers (31 women, 29 men) aged 14 to 30 years, who finished fixed orthodontic therapy at least three months before the study commencement and complained of discoloration on upper front teeth. The subjects were divided into four groups by treatment. The patients in group 1 received home bleaching, whereas those in groups 2 to 4 underwent in-office bleaching using a diode laser, a plasma arc and no light source, respectively. Tooth color was measured at baseline, one hour after the end of the bleaching procedure, and one week later, and the color alteration between different stages was compared among the groups. The severity of tooth sensitivity and the occurrence of other post-treatment complications were recorded. The color change between baseline and one week after treatment was greatest in the home-bleaching and the laser-assisted bleaching groups, and lowest in the plasma-arc bleaching group, although the difference between the groups was not significant (p > 0.05). Tooth sensitivity over 24 hours after bleaching was lowest in subjects who had undergone laser-assisted bleaching and highest in those who had received in-office bleaching without light (p < 0.05). All methods were effective in managing tooth discoloration after orthodontic treatment. Home bleaching produced favorable color alteration. Amongst the in-office approaches, laser-assisted bleaching should be considered as the best option, as it produced effective results with lowest tooth sensitivity and over a shorter period of time.


Assuntos
Sensibilidade da Dentina , Clareamento Dental , Descoloração de Dente , Dente , Adolescente , Adulto , Feminino , Humanos , Peróxido de Hidrogênio , Masculino , Adulto Jovem
14.
Iran Endod J ; 14(3): 197-201, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-36814945

RESUMO

Introduction: The aim of this study was to evaluate the effect of addition of nano-silica (SiO2) to mineral trioxide aggregate (MTA) on its setting time and porosity. Methods and Materials: The concentration 8% of nano-silica were prepared and added to the MTA powder. After mixing with water the setting time and porosity were evaluated and compared with pure MTA. Statistical analysis was performed using the t-test. The level of significance was set at 0.001. Results: The mean setting time of MTA+8% nano-silica (9.8±0.78) was significantly lower than MTA (23.3±2.16) ( P<0.001). Also the mean porosity by imbibition method in MTA+8% nano-silica (23.49±0.48) was significantly higher than MTA (15.69±2.10) (P<0.001). There was no significant difference in mean porosity by scanning electron microscope (SEM) method in MTA+8% nano-silica (31.26±10.73) and MTA (32.74±5.26) (P>0.001). Conclusion: This in vitro study showed us an addition of 8% of nano-silica to MTA reduced the setting time. Although evaluation by imbibition test showed increasing of porosity in nano-silica MTA compared with pure MTA.

15.
J Contemp Dent Pract ; 9(7): 9-16, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18997911

RESUMO

AIM: The aim of this randomized, double blind clinical trial was to compare three lining materials (Adper Prompt L-Pop, VivaSens, and Copalite) versus unlined restorations on postoperative cold sensitivity of class I amalgam restorations. METHODS AND MATERIALS: Potential subjects were screened for the presence of four initial class I carious lesions on posterior teeth. Each tooth was assigned to treatments according to a randomized block design. After cavity preparation, teeth were lined with either VivaSens, Adper Prompt L-Pop, or Copalite, and one tooth remained unlined and served as a control. The cavities were filled with high copper amalgam (Oralloy). The time taken for a subject to respond to a standardized cold stimulus (CRM) was recorded at baseline, 24 hours, one week, and one month after treatment. Participants filled out a self-report questionnaire at each time point. Data was gathered by analysis of variance (ANOVA) and Duncan Multiple Comparisons tests (alpha=0.05). RESULTS: Twenty subjects participated in this study. Comparisons within each group found no significant reduction in mean CRM for the Adper Prompt L-Pop group (P>0.05), but a significant difference in mean CRM for the VivaSens group was observed at one week and one month intervals after restoration (P<0.05). Copalite and the unlined groups showed significant mean CRM reductions after one day (P<0.05). No significant differences between groups receiving Adper Prompt L-Pop and Copalite were found at any time point (P>0.05). VivaSens showed more cold sensitivity than Adper Prompt L-Pop at one week and one month recalls (P<0.05), while the most cold sensitivity was found in the unlined group. CONCLUSION: Adper Prompt L-Pop and Copalite reduced postoperative sensitivity to cold more than VivaSens and unlined groups at all assessment time points, 24 hours, one week, and one-month post treatment. The subjects receiving Copalite, VivaSens, and unlined restorations experienced greater sensitivity to cold at one month compared to baseline, while subjects receiving the Adper Prompt L-Pop liner experienced no greater sensitivity to cold from baseline to one month. CLINICAL SIGNIFICANCE: Adper Prompt L-Pop as a liner under spherical high copper amalgam successfully reduced cold postoperative sensitivity.


Assuntos
Amálgama Dentário/efeitos adversos , Forramento da Cavidade Dentária , Restauração Dentária Permanente/efeitos adversos , Sensibilidade da Dentina/prevenção & controle , Cimentos de Resina , Adolescente , Adulto , Temperatura Baixa , Resinas Compostas , Sensibilidade da Dentina/etiologia , Método Duplo-Cego , Humanos , Resinas Vegetais , Adulto Jovem
16.
Biomimetics (Basel) ; 3(4)2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31105256

RESUMO

To evaluate the bleaching procedure and application of sodium ascorbate on dentin bond durability, the enamel surface of intact human third molars (n = 18) were removed, and the teeth were randomly divided into two groups for immediate and six-month bond strength evaluation. The specimens were further assigned into three subgroups according to treatment procedure, as follows: subgroup A, no bleaching (positive control) was performed prior to the etch-and-rinse bonding with single bond and subsequent build-up with Z250 composite; subgroup B, the samples were bleached with 20% carbamide peroxide 6 h/day for five consecutive days prior to bonding; and subgroup C, bleaching was performed as in subgroup B, after which 10% sodium ascorbate was applied on dentin surface for 10 min before the bonding procedures. A microtensile bond strength test was performed and the failure modes were evaluated under a stereomicroscope. The data were analyzed using two-way analysis of variance (ANOVA) and Tukey's post-hoc tests with a level of significance of 0.05. Bleaching significantly decreased the immediate and six-month bond strength. The application of sodium ascorbate had no significant effect on the immediate and six-month bond strength of bleached specimens. We conclude that the bleaching procedure may decrease the durability of the resin-dentin bond of the tested etch-and-rinse adhesive.

17.
Hum Pathol ; 38(5): 797-802, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17316759

RESUMO

We describe 3 unusual B-cell non-Hodgkin's lymphomas in which the entire tumors histologically mimicked marginal zone B-cell lymphoma. All patients were male (mean age, 65 years). Excisional biopsy from lymph node (2 of 3) and parotid gland (1 of 3) showed proliferation of monocytoid B-cells with plasmacytoid features (2 of 3) and conspicuous absence of large lymphoma cells (3 of 3). By immunohistochemistry, cyclin D1 was positive (3 of 3), CD23 was negative (3 of 3), and aberrant expression of CD5/CD43 was present in 1 case. Ki67 labeling was greater than 50% in 1 case and 10% to 25% in the other 2 cases. Evidence of the t(11;14) was detectable in all by molecular techniques. One patient died within 15 months, and the other 2 patients had widely disseminated diseases at the last follow-up (8 months). Based on these features, we believed that the best classification for these lesions is the marginal zone B-cell lymphoma-like mantle cell lymphoma.


Assuntos
Ciclina D1/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/microbiologia , Translocação Genética , Adulto , Idoso , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfonodos/patologia , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade
18.
J Endod ; 33(2): 173-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17258639

RESUMO

Cleaning the root canal is not possible without using proper irrigation. The aim of this in vitro study was to evaluate the effect of MTAD as a final irrigant on bacterial leakage of the root canal, and its interaction with two conventional root canal sealers. We used 132 extracted human maxillary anterior teeth. The teeth were randomly divided into three experimental groups (n=40) and two groups (n=6) of positive and negative control. In group 1, the smear layer was not removed and irrigation was performed using 5.25% NaOCl. In group 2, the smear layer was removed using EDTA, and in group 3, the smear layer was removed using MTAD according to the clinical protocol of use. The teeth in each group were obturated with gutta-percha and AH-Plus or Rickert sealer. The coronal portion of each root was placed in contact with inoculum of Streptococcus mutans in Brain Heart Infusion (BHI) culture media. Each root tip was placed in one bottle containing sterile BHI. Mean duration of bacterial penetration in groups 2 and 3 was significantly greater than in group 1, but there was no significant difference between groups 2 and 3. According to our findings, it takes longer for bacteria to penetrate when either EDTA or MTAD is used for smear layer removal. The root canals obturated with AH Plus showed significantly longer duration of resistance to bacterial penetration than canals obturated with Rickert.


Assuntos
Ácido Cítrico , Infiltração Dentária/prevenção & controle , Doxiciclina , Polissorbatos , Irrigantes do Canal Radicular , Análise de Variância , Infiltração Dentária/microbiologia , Ácido Edético , Resinas Epóxi , Humanos , Incisivo , Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Camada de Esfregaço , Hipoclorito de Sódio , Streptococcus mutans
19.
Hum Pathol ; 37(11): 1473-81, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16949917

RESUMO

Atypical proliferations of immature cervical squamous metaplasia were reviewed and correlated with p16 and Ki-67 expression to determine whether immunoprofiling could enable more conventional classification. The longitudinal outcome of atypical immature metaplasia (AIM) and predictive role of biomarker expression were also investigated. All atypias of immature squamous metaplasia in the year 2000 were reviewed and stained with p16 and Ki-67. Biomarker features were evaluated and the Ki-67 index calculated. Diagnoses were correlated with the immunoprofile of each antibody, both separately and combined. The progression to squamous intraepithelial lesion (SIL) of lesions reclassified as AIM was determined, and biomarker immunoprofiles were correlated with outcome. The 172 atypias were reviewed as 3 (1.7%) negative, 54 (31.4%) benign, 60 (34.9%) AIM, 43 (25%) low-grade SIL (LSIL), and 12 (6.9%) high-grade SIL (HSIL). HSIL correlated significantly with a combined high index (>15%) and p16 diffusely positive profile (P = .01). Benign diagnoses correlated significantly with a low index (1%-15%) and p16 negative or focal profile (P = .01). AIM and LSIL correlations were not significant, but their profiles were very variable and nearly identical. AIM was the only pathology in 43 cases, and follow-up was available for 32 (74.4%). SIL developed in 66% (50% LSIL and 16% HSIL) and p16 positivity correlated (P = .02). p16 and Ki-67 immunoprofiling are reliable in reclassifying some atypical proliferations of immature squamous metaplasia as HSIL and some as benign. The similarity between AIM and LSIL in regard to their immunoprofile as well as outcome suggests AIM is a morphological type of LSIL.


Assuntos
Biomarcadores Tumorais/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Antígeno Ki-67/análise , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Feminino , Humanos , Imuno-Histoquímica , Metaplasia/patologia
20.
Cancer Res ; 63(13): 3575-84, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12839944

RESUMO

Activation of alternative growth factor pathways after androgen withdrawal is one mechanism mediating androgen-independent (AI) progression in advanced prostate cancer. Insulin-like growth factor (IGF) I activation is modulated by a family of IGF binding proteins (IGFBPs). Although IGFBP-2 is one of the most commonly overexpressed genes in hormone refractory prostate cancer, the functional significance of changes in IGF-I signaling during AI progression remains poorly defined. In this article, we characterize changes in IGFBP-2 in the LNCaP tumor model after androgen withdrawal and evaluate its functional significance in AI progression using gain-of-function and loss-of-function analyses. IGFBP-2 mRNA and protein levels increase 2-3-fold after androgen withdrawal in LNCaP cells in vitro in LNCaP tumors during AI progression in vivo. Increased IGFBP-2 levels after castration were also identified using a human prostate tissue microarray of untreated and posthormone therapy-treated prostatectomy specimens. LNCaP cell transfectants that stably overexpressed IGFBP-2 progressed more rapidly after castration than control tumors. Antisense oligonucleotides (ASOs) targeting the translation initiation site of IGFBP-2 reduced IGFBP-2 mRNA and protein expression by >70% in a dose-dependent and sequence-specific manner. ASO-induced decreases in IGFBP-2-reduced LNCaP cell growth rates and increased apoptosis 3-fold. LNCaP tumor growth and serum prostate-specific antigen levels in mice treated with castration plus adjuvant IGFBP-2 ASOs were significantly reduced compared with mismatch control oligonucleotides. Increased IGFBP-2 levels after androgen ablation may represent an adaptive response that helps potentiate IGF-I-mediated survival and mitogenesis and promote androgen-independent tumor growth. Inhibiting IGFBP-2 expression using ASO technology may offer a treatment strategy to delay AI progression.


Assuntos
Androgênios/fisiologia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Orquiectomia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Sequência de Bases , Divisão Celular , Primers do DNA , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Biossíntese de Proteínas , Transcrição Gênica/efeitos dos fármacos
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