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1.
Braz. j. oral sci ; 20: e219342, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1253927

ABSTRACT

Aim: The aim of this study was to compare the microtensile bond strength (µTBS) and the characteristics of the adhesive interface of Scotchbond Universal - SU ­ etch-and-rise mode (3M ESPE) and Adper Scotchbond Multi-Purpose - MP (3M ESPE) to dentin over time. Methods: Class I cavity preparations were performed in 60 human molars that were randomly divided according to the dentin bonding system (DBS) used (n=30): (1) Acid conditioning + SU and (2) Acid conditioning + MP. For bonding strength (BS) analysis, 30 teeth (n = 15) were sectioned into sticks and submitted to the microtensile test in a universal testing machine after 24 hours and 12 months. The adhesive interface of the others 30 teeth was analyzed in a confocal microscope after 24 hours and 12 months. The data of µTBS were analyzed by two-way repeated measures ANOVA and Tukey's HSD (α = 0.05). Results: SU presented the lowest DBS compared to MP (p=0.000). Time did not influenced DBS for both adhesive systems (p=0.177). Confocal microscopy analysis showed no cracks between both adhesive systems tested. Conclusion: The results indicate that MP - µTBS showed a better performance compared to SU in total-etch mode


Subject(s)
Humans , Dentin-Bonding Agents , Microscopy, Confocal , Dentin , Methacrylates
2.
Braz. j. oral sci ; 20: e211194, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1253930

ABSTRACT

Aim: The aim of this study was to evaluate the effect of ethanol-conditioned dentin on endodontic sealer penetration into dentinal tubules by confocal laser scanning microscopy (CLSM). Methods: Forty human maxillary anterior teeth were instrumented and divided into four groups (n = 10) according to the drying methods: 1) wet: vacuum only, 2) paper points: vacuum + absorbent paper points, (3) 70% ethanol: 70% ethanol (1 min) + vacuum + absorbent paper points, and (4) 100% ethanol: 100% ethanol (1 min) + vacuum + absorbent paper points. All root canals were filled with resin-based endodontic sealer. Four sections from each third (cervical, middle, and apical) were examined by CLSM. Root canal wall perimeter infiltrated by sealer, maximum depth of sealer penetration, percentage of penetrated area, and fluorescence intensity of rhodamine B were measured. Statistical analysis was performed by analysis of variance and Tukey's tests (α = 0.05). Results: No statistical difference was found when percentage of root canal wall coverage infiltrated by sealer were compared. The groups in which ethanol solutions were used presented greater depth of sealer penetration, higher percentage of penetrated area, and higher fluorescence intensity of rhodamine B (p< 0.05) when compared with the wet and paper point groups. Overall, 100% ethanol produced better results than 70% ethanol, except for rhodamine B intensity (cervical third). In addition, the absorbent paper points drying method behaved better than did vacuum only group, except for rhodamine B intensity (apical third). Conclusion: Ethanol-conditioned dentin improved the penetration of resin-based sealer into dentinal tubules, especially at the concentration of 100%


Subject(s)
Humans , Wettability , Microscopy, Confocal , Resin Cements , Dentin , Ethanol , Endodontics
3.
An. bras. dermatol ; 96(5): 609-612, Sept.-Oct. 2021. graf
Article in English | LILACS | ID: biblio-1345155

ABSTRACT

Abstract The penile localization of pigmented Bowen's disease has been rarely reported and has been mostly related to human papillomavirus infection. Early diagnosis and treatment are important to prevent progression to invasive squamous cell carcinoma. However, diagnosis can be challenging because it may be difficult to distinguish from melanoma, even using dermoscopy. Reflectance confocal microscopy may be useful in suggesting the bedside diagnosis before the histopathological confirmation. A case of penile pigmented Bowen's disease is described along with its dermoscopy and reflectance confocal microscopy findings and their correlation with histopathology.


Subject(s)
Humans , Skin Neoplasms/diagnostic imaging , Bowen's Disease/diagnostic imaging , Microscopy, Confocal , Dermoscopy , Diagnosis, Differential
4.
Rev. cuba. oftalmol ; 34(1): e929, 2021. graf
Article in Spanish | LILACS, CUMED | ID: biblio-1289535

ABSTRACT

La queratitis por Acanthamoeba es una infección corneal de baja incidencia, condicionada por varios factores, pero con manifestación clínica variada y sintomatología típica. En su fase epitelial debe ser diferenciada de otras queratitis, específicamente de la queratitis por herpes simple, por la similitud entre ambas en cuanto a las características de la lesión corneal. La microscopia confocal in vivo constituye una alternativa diagnóstica. Es una biopsia fotográfica en cuyas imágenes podemos describir los quistes y trofozoítos de Acanthamoeba desde etapas iniciales, que nos ayudan a diferenciarla de otros tipos de queratitis e iniciar el tratamiento precoz. Se realizó una búsqueda de artículos publicados, con el objetivo de mostrar las imágenes por microscopia confocal de la fase epitelial de la infección corneal por Acanthamoeba y herpes simple. Se utilizó la plataforma Infomed, específicamente la Biblioteca Virtual de Salud(AU)


Acanthamoeba keratitis is a low-incidence corneal infection caused by several factors and characterized by a variety of clinical manifestations and typical symptoms. In its epithelial phase, it should be differentiated from other keratitis, particularly from herpes simplex keratitis, due to the similar characteristics of the corneal lesion. In vivo confocal microscopy is a diagnostic alternative consisting in a photographic biopsy showing images of Acanthamoeba cysts and trophozoites since their initial stages, thus allowing differentiation from other types of keratitis and the initiation of early treatment. A search was conducted of published papers with the purpose of showing confocal microscopy images of the epithelial phase of Acanthamoeba and herpes simplex corneal infection. Use was made of the platform Infomed, specifically the Virtual Health Library(AU)


Subject(s)
Humans , Acanthamoeba Keratitis/epidemiology , Keratitis, Herpetic/diagnostic imaging , Microscopy, Confocal/methods , Review Literature as Topic , Databases, Bibliographic
5.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 352-360, Mar.-Apr. 2021. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1248941

ABSTRACT

In this study, the toxic effects of melittin on Madin-Darby Bovine Kidney cells (MDBK) were analyzed with respect to mitochondrial functionality by reduction of MTT and flow cytometry, apoptosis potential, necrosis, oxygen reactive species (ROS) production, lipid peroxidation, and DNA fragmentation using flow cytometry and cell membrane destabilization by confocal microscopy. The toxicity presented dose-dependent characteristics and mitochondrial activity was inhibited by up to 78.24 ±3.59% (P<0.01, n = 6) in MDBK cells exposed to melittin (10µg/mL). Flow cytometry analysis revealed that melittin at 2µg/mL had the highest necrosis rate (P<0.05) for the cells. The lipoperoxidation of the membranes was also higher at 2µg/mL of melittin (P<0.05), which was further confirmed by the microphotographs obtained by confocal microscopy. The highest ROS production occurred when the cells were exposed to 2.5µg/mL melittin (P<0.05), and this concentration also increased DNA fragmentation (P<0.05). There was a significative and positive correlation between the lipoperoxidation of membranes with ROS (R=0.4158), mitochondrial functionality (R=0.4149), and apoptosis (R=0.4978). Thus, the oxidative stress generated by melittin culminates in the elevation of intracellular ROS that initiates a cascade of toxic events in MDBK cells.(AU)


Neste estudo, os efeitos tóxicos da melitina em células Madin-Darby Bovine Kidney (MDBK) foram analisados quanto à funcionalidade mitocondrial, por redução de MTT e citometria de fluxo, potencial de apoptose, necrose, produção de espécies reativas de oxigênio (ROS), peroxidação lipídica e fragmentação de DNA, utilizando-se citometria de fluxo e desestabilização da membrana celular, por microscopia confocal. A toxicidade apresentou características dose-dependentes e a atividade mitocondrial foi inibida até 78,24±3,59% (P<0,01, n = 6) em células MDBK expostas à melitina (10µg/mL). Análises por citometria de fluxo revelaram que a melitina a 2µg/mL apresentou o maior índice necrótico celular (P<0,05). A maior lipoperoxidação de membranas também foi na concentração de 2µg/mL de melitina (P<0,05), o que foi posteriormente confirmado por microscopia confocal. A maior produção de ROS aconteceu quando as células foram expostas a 2,5µg/mL de melitina (P<0,05), e essa concentração também aumentou a fragmentação de DNA (P<0,05). Houve uma significativa correlação positiva entre a lipoperoxidação de membranas e a produção de ROS (R=0,4158), funcionalidade mitocondrial (R=0,4149) e apoptose (R=0,4978). Portanto, o estresse oxidativo gerado pela melitina culminou na elevação de ROS intracelular, que inicia uma cascata de eventos tóxicos nas células MDBK.(AU)


Subject(s)
Reactive Oxygen Species/adverse effects , Apoptosis , Cytotoxins/analysis , Melitten/analysis , Bee Venoms/analysis , Microscopy, Confocal , Flow Cytometry
6.
J. appl. oral sci ; 29: e20200733, 2021. graf
Article in English | LILACS | ID: biblio-1154616

ABSTRACT

Abstract Enterococcus faecalis (E. faecalis), one of the main pathogens responsible for refractory periapical periodontitis and nosocomial infections, exhibits markedly higher pathogenicity in biofilms. Objectives Studies have shown that caseinolytic protease P (ClpP) is involved in biofilm formation. However, to date, few studies have investigated the role of ClpP in the survival of E. faecalis, and in enhancing biofilm formation. Therefore, we investigated the role of ClpP in the formation of E. faecalis biofilms. Methodology In our study, we used homologous recombination to construct clpP deleted and clpP complement strains of E. faecalis ATCC 29212. A viable colony counting method was used to analyze the growth patterns of E. faecalis. Crystal violet staining (CV) and confocal scanning laser microscopy (CLSM) were used to characterize biofilm mass formation and scanning electron microscopy (SEM) was used to observe the biofilm microstructure. Data was statistically analyzed via Student's t-test or one-way analysis of variance (ANOVA). Results The results exhibited altered growth patterns for the clpP deletion strains and depleted polysaccharide matrix, resulting in reduced biofilm formation capacity compared to the standard strains. Moreover, ClpP was observed to increase biofilm formation in E. faecalis. Conclusion Our study shows that ClpP can increase biofilm formation in E. faecalis and emphasizes the importance of ClpP as a potential target against E. faecalis.


Subject(s)
Humans , Enterococcus faecalis , Biofilms , Peptide Hydrolases , Virulence , Microscopy, Electron, Scanning , Microscopy, Confocal , Endopeptidase Clp
7.
Article in Chinese | WPRIM | ID: wpr-878708

ABSTRACT

Diabetic peripheral neuropathy(DPN),a chronic diabetic microvascular complication with a high incidence among diabetic patients,increases the risk of diabetic foot and amputation.Many methods are available for screening and evaluating DPN,including traditional 10 g monofilament,tuning fork and vibration perception,and tendon reflex tests,which should be combined with some nerve function score systems to improve the detection rate and accuracy for DPN.In recent years,a number of noninvasive new techniques have been developed for the evaluation of nerve injury,such as corneal confocal microscopy,quantitative sensory testing,current perception threshold test,sympathetic sudomotor function evaluation,and quantitative detection of skin advanced glycation end products.This paper reviews these noninvasive methods for screening and evaluating DPN to help clinicians detect and focus on DPN early.


Subject(s)
Cornea , Diabetes Mellitus , Diabetic Foot , Diabetic Neuropathies/diagnosis , Humans , Mass Screening , Microscopy, Confocal
8.
Int. j. odontostomatol. (Print) ; 14(4): 632-638, dic. 2020. tab, graf
Article in English | LILACS | ID: biblio-1134550

ABSTRACT

ABSTRACT: The aim of this in vitro study was to investigate the influence of ethylenediaminetetraacetic acid (EDTA) associated with the benzalkonium chloride (BAK) on the adhesion and formation of Enterococcus faecalis biofilms attached to coated dentin. Discs standard bovine dentin blocks were treated with the coating materials evaluated: Saline solution (control), 17 % EDTA, 17 % EDTA associated with 1 % BAK for 5 minutes and subsequently washed with saline solution. Afterwards, biofilms of E. faecalis (ATCC 29212) were grown on the surface of coated dentin blocks for time intervals of 1 hour and 7 days (n = 20) and were subsequently washed with phosphate-buffered saline (PBS). Bacterial viability and total biovolume were analyzed by confocal laser scanning microscopy (CLSM) using the Live/Dead technique. Nonparametric Kruskal-Wallis followed by Dunn tests were used to determine statistical differences (a = 5 %). The 17 % EDTA + 1 % BAK group showed significantly lower biovolume and bacterial viability values at the end of 1 hour (p < 0.05). After 7 days of contamination, the 17 % EDTA and 17 % EDTA + 1 % BAK groups showed similar results that differed statistically from those of the control group (p < 0.05). The saline solution group showed higher values. The use of BAK associated with EDTA on dentin blocks surfaces before exposure to contamination was able to interfere in the adhesion of E. faecalis to dentin. Also, dentin treatment by BAK associated with a chelating agent influences the secondary biofilm formation, which could have important effects on the long-term success of root canal treatment.


RESUMEN: El objetivo del estudio consistió en investigar in vitro, la influencia del ácido etilendiamino-tetraacético (EDTA) con cloruro de benzalconio (BAK) en la adhesión y formación de biopelículas de Enterococcus faecalis a la dentina. Discos de dentina bovina fueron tratadas con solución salina (control), 17 % de EDTA, 17% de EDTA asociado con 1 % de BAK durante 5 minutos y lavadas con solución salina. Las biopelículas de E. faecalis (ATCC 29212) se cultivaron sobre los discos de dentina durante intervalos de tiempo de 1 hora y 7 días (n = 20), lavados con solución salina tamponada con fosfato (PBS). La viabilidad bacteriana y el biovolumen total se analizaron mediante microscopía de barrido por láser (CLSM) utilizando la técnica Live / Dead. Se realizó prueba no paramétrica de Kruskal-Wallis, seguida por Dunn con una diferencia estadística (a = 5 %). El grupo de 17 % EDTA + 1 % BAK mostró valores significativamente menores de biovolumen y viabilidad bacteriana al final de 1 hora (p < 0,05). Después de 7 días de contaminación, los grupos de 17 % EDTA y 17 % EDTA + 1 % BAK mostraron resultados similares que diferían estadísticamente del grupo control (p < 0,05). La solución salina mostró valores más altos. La asociación de BAK con EDTA antes de la contaminación interfirió en la adhesión de E. faecalis. Además, el tratamiento de la dentina por BAK asociado con EDTA influye en la formación de biopelículas secundarias, lo que podría tener efectos importantes sobre el éxito a largo plazo del tratamiento del conducto radicular.


Subject(s)
Animals , Cattle , Bacterial Adhesion/drug effects , Edetic Acid/pharmacology , Enterococcus faecalis/growth & development , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dentin/microbiology , Benzalkonium Compounds/pharmacology , Statistical Analysis , Microscopy, Confocal , Saline Solution
9.
Braz. dent. j ; 31(2): 109-115, Mar.-Apr. 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1132277

ABSTRACT

Abstract This study aimed to evaluate penetrability on dentinal tubule of a new bioceramic sealer through confocal laser scanning microscopy (CLSM). A specific fluorophore (Fluo-3) was mixed with the sealer. Forty distobuccal roots from maxillary molars were selected, and root canal preparation was carried out with Wave One Gold # 35.06 instruments. Roots were randomly assigned to 4 groups according to the filling procedures: Bioceramic/Lentulo (Sealer Plus BC); Bioceramic/EasyClean group, three activation of the sealer (3x20 s) with Easy Clean instrument; Bioceramic/Irrisonic: ultrasonic activation for 30 s; and AHplus/Lentulo: epoxy resin based sealer (AH Plus) was utilized with the same protocol as the BC/LE group. After 72 h, specimens were transversally sectioned at 2 and 7 mm from root apex and then analyzed through CLSM. Sealer penetration area on dentinal tubule was measured by Adobe Photoshop CC2018. Kruskal Wallis and Wilcoxon T tests were carried out. Penetrability results were similar for both sealers regardless of which technique was performed to activate them inside the root canal (p>0.05). It is reasonable to conclude that penetration of bioceramic and epoxy resin based sealers occurred unimpressively. The type of instrument used to activate bioceramic sealer did not affect penetrability. Fluo 3 should be recommended as the fluorophore to evaluate dentinal tubule penetration of bioceramic sealers.


Resumo Este estudo objetivou avaliar a penetração nos túbulos dentinários de um novo cimento biocerâmico utilizando microscopia confocal de varredura a laser (MCVL). Um fluoróforo específico (Fluo-3) foi misturado com o cimento. Quarenta raízes distovestibulares de molares superiores foram selecionados e o preparo do canal radicular foi realizado com instrumentos Wave One Gold #35.06. As raízes foram divididas randomicamente em quatro grupos de acordo com os procedimentos obturadores: Bioceramic/Lentulo: cimento biocerâmico (Sealer Plus BC); Bioceramic/EasyClean: três ativações do cimento com instrumento Easy Clean (3 x 20 s); Bioceramic/Irrisonic: ativação ultrassônica do cimento por 30 s e AHplus/Lentulo: cimento à base de resina epóxica (AH Plus) foi utilizado com o mesmo protocolo que o grupo Bioceramic/Lentulo. Após 72h, os espécimes foram seccionados transversalmente em 2 e 7 mm do ápice radicular e analisados com MCVL. A área de penetração nos túbulos dentinários foi mensurada com Adobe Photoshop CC2018. O teste de Kruskal Wallis e T de Wilcoxon foram realizados. Os resultados de penetração foram similares para ambos os cimentos independentemente de qual técnica foi utilizada para ativá-los no interior do canal radicular (p>0,05). É razoável concluir que a penetração de cimentos biocerâmicos e à base de resina epóxica ocorreram de forma pouco expressiva. O tipo de ativação do cimento biocerâmcio não afeta sua penetrabilidade nos túbulos dentinários. Fluo 3 deve ser recomendado como o fluoróforo para avaliar a penetração intratubular de cimentos biocerâmicos.


Subject(s)
Root Canal Filling Materials , Calcium , Root Canal Obturation , Silicates , Calcium Compounds , Microscopy, Confocal , Dental Pulp Cavity , Epoxy Resins
10.
Arq. bras. oftalmol ; 83(2): 146-148, Mar.-Apr. 2020. graf
Article in English | LILACS | ID: biblio-1088972

ABSTRACT

ABSTRACT Lisch corneal dystrophy is a rare corneal disease characterized by the distinctive feature of highly vacuolated cells. Although this feature is important, the nature of these vacuoles within corneal cells remains unknown. Here, we sought to analyze corneal cells from a patient diagnosed with Lisch dystrophy to characterize the vacuoles within these cells. Analyses using histopathology examination, confocal microscopy, and transmission electron microscopy were all consistent with previous descriptions of Lisch cells. Importantly, the vacuoles within these cells appeared to be autophagosomes and autolysosomes, and could be stained with an anti-microtubule-associated protein 1A/1B-light chain 3 (LC3) antibody. Taken together, these findings indicate that the vacuoles we observed within superficial corneal cells of a patient with Lisch corneal dystrophy constituted autophagosomes and autolysosomes; this finding has not been previously reported and suggests a need for further analyses to define the role of autophagy in this ocular disease.


RESUMO A distrofia corneana de Lisch é uma doença rara, caracterizada principalmente pela presença de células altamente vacuoladas. Embora esta característica seja importante, a natureza desses vacúolos dentro das células da córnea permanece des conhecida. Aqui, procuramos analisar as células da córnea de um paciente diagnosticado com distrofia de Lisch para caracte rizar os vacúolos dentro dessas células. Análises utilizando exame histopatológico, microscopia confocal e microscopia eletrônica de transmissão foram todas consistentes com descrições previas de células de Lisch. Importante, os vacúolos dentro dessas células pareciam ser autofagossomos e autolisossomos, e po deriam ser corados com um anticorpo proteico 1A/1B-cadeia leve 3 (LC3) da proteína anti-microtúbulo associado a microtúbulos. Em conjunto, esses achados indicam que os vacúolos observados nas células superficiais da córnea de um paciente com distrofia corneana de Lisch constituíram autofagossomos e autolisossomos. Esse achado não foi relatado anteriormente e sugere a necessidade de mais análises para definir o papel da autofagia nessa doença ocular.


Subject(s)
Humans , Female , Adult , Vacuoles/pathology , Corneal Dystrophies, Hereditary/pathology , Autophagosomes/pathology , Corneal Dystrophies, Hereditary/diagnostic imaging , Microscopy, Confocal/methods , Corneal Opacity/pathology , Corneal Opacity/diagnostic imaging , Tomography, Optical Coherence/methods , Microscopy, Electron, Transmission/methods , Microautophagy
11.
Rev. cuba. oftalmol ; 33(1): e692, ene.-mar. 2020. tab
Article in Spanish | LILACS, CUMED | ID: biblio-1126725

ABSTRACT

RESUMEN Objetivo: Identificar las características morfológicas del epitelio, el estroma y el endotelio corneal, así como la densidad celular de este último mediante el empleo de la microscopia confocal de la córnea en pacientes diabéticos. Métodos: Se realizó un estudio descriptivo, comparativo, en 90 ojos; 60 de ellos pertenecientes a pacientes diabéticos (30 tipo 1 y 30 tipo 2) y 30 ojos a pacientes supuestamente sanos. El estudio se realizó en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" entre enero del año 2012 y enero de 2017. Resultados: Predominó el sexo masculino con 66,7 por ciento en los pacientes con diabetes mellitus tipo 1; el sexo femenino en los pacientes con diabetes mellitus tipo 2 (60 por ciento) y aparentemente sanos (56,7 por ciento). En los pacientes con diabetes mellitus tipo 1 fueron más frecuentes las edades entre 45 y 54 años (33,3 por ciento) y entre 55 y 66 años en los pacientes con diabetes mellitus tipo 2 y aparentemente sanos con 60 y 40 por ciento respectivamente. La morfología del epitelio y el estroma corneal fue normal en el 86,7 y 87,3 por ciento respectivamente. Predominaron las alteraciones de la morfología endotelial en pacientes diabéticos tipo 1 (73,3 por ciento), así como el polimegatismo y el pleomorfismo (73,3 y 56,7 por ciento respectivamente) y la densidad celular más baja (2 222,76 células /mm2). Conclusiones: La ausencia de alteraciones morfológicas del epitelio y el estroma corneal y la presencia de polimegatismo y de pleomorfismo fueron los hallazgos más frecuentes(AU)


ABSTRACT Objective: Identify the morphological characteristics of the corneal epithelium, stroma and endothelium, as well as the cell density of the endothelium by means of confocal microscopy of the cornea in diabetic patients. Methods: A descriptive comparative study was conducted of 90 eyes: 60 from diabetic patients (30 type 1 and 30 type 2) and 30 from supposedly healthy patients, at Ramón Pando Ferrer Cuban Institute of Ophthalmology from January 2012 to January 2017. Results: A predominance was found of the male sex (66.7 percent) among patients with diabetes mellitus type 1 and of the female sex among patients with diabetes mellitus type 2 (60 percent) and seemingly healthy patients (56.7 percent). The most common age ranges were 45-54 years for patients with diabetes mellitus type 1 (33.3 percent) and 55-66 years for patients with diabetes mellitus type 2 (60 percent) and seemingly healthy patients (40 percent). Morphology of the corneal epithelium and stroma was normal in 86.7 percent and 87.3 percent, respectively. In type 1 diabetic patients there was a predominance of endothelial morphological alterations (73.3 percent), polymegethism and pleomorphism (73.3 percent and 56.7 percent, respectively) and the lowest cell density (2 222.76 cells /mm2). Conclusions: Absence of morphological alterations of the corneal epithelium and stroma, as well as the presence of polymegethism and pleomorphism were the most common findings(AU)


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Cell Count/methods , Cornea/abnormalities , Diabetes Mellitus, Type 1/etiology , Diabetes Mellitus, Type 2/etiology , Epidemiology, Descriptive , Microscopy, Confocal/methods
13.
J. appl. oral sci ; 28: e20190005, 2020. tab, graf
Article in English | LILACS | ID: biblio-1056579

ABSTRACT

Abstract Chitosan is a natural, biocompatible chelating substance with potential for dental use. This study compared the effects of final canal irrigation with chitosan and EDTA on dentin microhardness, sealer dentin tubules penetration capacity, and push-out strength. Methodology: Fifty canine roots were distributed according to the final irrigation protocol (n=10): G1- 15% EDTA with conventional irrigation; G2- 15% EDTA with Endovac; G3- 0.2% chitosan with conventional irrigation; G4- 0.2% chitosan with Endovac; and G5- without irrigation. Specimens were obturated (AH Plus) and sectioned in 3 slices per root third. The first slice was used for microhardness and sealer penetration assessments under a laser confocal microscope. The second was utilized in a push-out strength test. The third slice was discarded. Data were analyzed using 2-way ANOVA and Tukey's post hoc test (α<0.05). Failure mode was determined at x40 magnification. Results: Microhardness reduction was more significant in groups G2 and G4 (p<0.05). Sealer penetration through dentin was significantly greater in group G2 (p<0.05). There was no significant difference between groups G1, G3, and G4 (p>0.05). In general, all experimental groups presented similar bond resistance (p>0.05) that significantly differed from the control (p<0.001). Mixed type failures were predominant. Conclusions: In general, 0.2% chitosan and 15% EDTA solutions act in a similar manner with regard to the variables studied. The use of Endovac potentiates the effect of these solutions.


Subject(s)
Humans , Root Canal Irrigants/chemistry , Chelating Agents/chemistry , Dental Bonding/methods , Edetic Acid/chemistry , Dentin/drug effects , Chitosan/chemistry , Reference Values , Root Canal Filling Materials/chemistry , Surface Properties/drug effects , Materials Testing , Reproducibility of Results , Analysis of Variance , Microscopy, Confocal , Shear Strength , Epoxy Resins/chemistry , Hardness Tests , Middle Aged
14.
Braz. oral res. (Online) ; 34: e050, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1132693

ABSTRACT

Abstract Candida infection is an important cause of morbidity and mortality in immunocompromised patients. The increase in its incidence has been associated with resistance to antimicrobial therapy and biofilm formation. The aim of this study was to evaluate the efficacy of tea tree oil (TTO) and its main component - terpinen-4-ol - against resistant Candida albicans strains (genotypes A and B) identified by molecular typing and against C. albicans ATCC 90028 and SC 5314 reference strains in planktonic and biofilm cultures. The minimum inhibitory concentration, minimum fungicidal concentration, and rate of biofilm development were used to evaluate antifungal activity. Results were obtained from analysis of the biofilm using the cell proliferation assay 2,3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) and confocal laser scanning microscopy (CLSM). Terpinen-4-ol and TTO inhibited C. albicans growth. CLSM confirmed that 17.92 mg/mL of TTO and 8.86 mg/mL of terpinen-4-ol applied for 60 s (rinse simulation) interfered with biofilm formation. Hence, this in vitro study revealed that natural substances such as TTO and terpinen-4-ol present promising results for the treatment of oral candidiasis.


Subject(s)
Terpenes/pharmacology , Candida albicans/drug effects , Biofilms/drug effects , Tea Tree Oil/pharmacology , Reference Values , Terpenes/chemistry , Acrylic Resins , Candida albicans/growth & development , Microbial Sensitivity Tests , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Microscopy, Confocal , Biofilms/growth & development , Tea Tree Oil/chemistry , Denture Bases/microbiology , Antifungal Agents/pharmacology
15.
J. appl. oral sci ; 28: e20190371, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1056595

ABSTRACT

Abstract Objective This study aims to evaluate the influence of different air-abrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. Methodology Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. Results The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal ( t )-, and rhombohedral ( r )-ZrO2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r -ZrO2 phase increased, with a significant amount of r -ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t -ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. Conclusion Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.


Subject(s)
Zirconium/chemistry , Dental Bonding/methods , Resin Cements/chemistry , Air Abrasion, Dental/methods , Aluminum Oxide/chemistry , Reference Values , Surface Properties , Tensile Strength , X-Ray Diffraction/methods , Materials Testing , Reproducibility of Results , Analysis of Variance , Microscopy, Confocal/methods , Flexural Strength , Hot Temperature
16.
J. appl. oral sci ; 28: e20190516, 2020. graf
Article in English | LILACS, BBO | ID: biblio-1090775

ABSTRACT

Abstract This study investigated the effect of a calcium hydroxide (CH) paste (CleaniCal®) containing N-2-methyl pyrrolidone (NMP) as a vehicle on Enterococcus faecalis (E. faecalis) biofilms compared with other products containing saline (Calasept Plus™) or propylene glycol (PG) (Calcipex II®). Methodology Standardized bovine root canal specimens were used. The antibacterial effects were measured by colony-forming unit counting. The thickness of bacterial microcolonies and exopolysaccharides was assessed using confocal laser scanning microscopy. Morphological features of the biofilms were observed using field-emission scanning electron microscopy (FE-SEM). Bovine tooth blocks covered with nail polish were immersed into the vehicles and dispelling was observed. The data were analyzed using one-way analysis of variance and Tukey tests (p<0.05). Results CleaniCal® showed the highest antibacterial activity, followed by Calcipex II® (p<0.05). Moreover, NMP showed a higher antibacterial effect compared with PG (p<0.05). The thickness of bacteria and EPS in the CleaniCal® group was significantly lower than that of other materials tested (p<0.05). FE-SEM images showed the specimens treated with Calasept Plus™ were covered with biofilms, whereas the specimens treated with other medicaments were not. Notably, the specimen treated with CleaniCal® was cleaner than the one treated with Calcipex II®. Furthermore, the nail polish on the bovine tooth block immersed in NMP was completely dispelled. Conclusions CleaniCal® performed better than Calasept Plus™ and Calcipex II® in the removal efficacy of E. faecalis biofilms. The results suggest the effect might be due to the potent dissolving effect of NMP on organic substances.


Subject(s)
Animals , Cattle , Pyrrolidinones/pharmacology , Root Canal Irrigants/pharmacology , Calcium Hydroxide/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Potassium Chloride/pharmacology , Potassium Chloride/chemistry , Pyrrolidinones/chemistry , Root Canal Irrigants/chemistry , Materials Testing , Calcium Chloride/pharmacology , Calcium Chloride/chemistry , Calcium Hydroxide/chemistry , Microscopy, Electron, Scanning , Sodium Chloride/pharmacology , Sodium Chloride/chemistry , Colony Count, Microbial , Reproducibility of Results , Analysis of Variance , Sodium Bicarbonate/pharmacology , Sodium Bicarbonate/chemistry , Statistics, Nonparametric , Microscopy, Confocal , Drug Combinations
17.
Braz. dent. sci ; 23(3): 1-8, 2020. ilus
Article in English | LILACS, BBO | ID: biblio-1104271

ABSTRACT

Objective: The influence of four root canal filling techniques on the penetration of an endodontic sealer into dentinal tubules and the gutta percha/ sealer ratio (GP/SR) in root canals was evaluated using confocal laser scanning microscopy (CLSM). Material and Methods: Roots of the maxillary central incisors (n=40) were prepared with ProTaper Universal files up to file F5 and assigned to five groups: continuous wave condensation, lateral condensation, single cone, Thermafill®, and negative control group. After root canal filling with gutta-percha and AH26, along with the addition of 0.01% fluorescein, the roots were cut into 2-mm slices. Using CLSM, the specimens were transversely sectioned at 3, 6, and 10 mm from the apex. Results: Sealer penetration was deeper and more frequent at 10 mm than at the 6mm and 3mm for all obturation technique. Penetration was not significantly affected by obturation techniques except single master cone tecnique. Single cone technique demonstrated the lowest sealer penetration at all levels. However, sealer thickness was strongly dependent on obturation technique. Termafill® demostrated superior GP ratio followed by continuous wave condensation, lateral condensation and single cone. Conclusion: In conclusion, the single cone technique resulted in lower sealer penetration than the other techniques, which did not differ significantly from each other. However, sealer thickness was strongly dependent on obturation technique. Termafill® demostrated superior GP ratio followed by continuous wave condensation, lateral condensation and single cone. (AU)


Objetivo: A influência de quatro técnicas de obturação do canal radicular na penetração de um cimento endodôntico nos túbulos dentinários e a relação gutapercha / cimento (GP / CIM) em canais radiculares foram avaliadas por microscopia de varredura confocal a laser (MVCL). Material e Métodos: As raízes de incisivos centrais superiores (n = 40) foram preparadas com limas ProTaper Universal até a lima F5 e distribuídas em cinco grupos: condensação de onda contínua, condensação lateral, cone único, Thermafill® e grupo de controle negativo. Após o preenchimento do canal radicular com guta-percha e AH26, juntamente com a adição de 0,01% de fluoresceína, as raízes foram cortadas em fatias de 2 mm. Usando MVCL, as amostras foram seccionadas transversalmente a 3, 6 e 10 mm do ápice. Resultados: A penetração do cimento foi mais profunda e mais frequente em 10 mm do que nos 6 mm e 3 mm para todas as técnicas de obturação. A penetração não foi significativamente afetada pelas técnicas de obturação, exceto pela técnica de cone mestre único. A técnica de cone único demonstrou a menor penetração do cimento em todos os níveis. No entanto, a espessura do cimento foi fortemente dependente da técnica de obturação. O Termafill® demonstrou uma relação superior de GP, seguida por condensação de onda contínua, condensação lateral e cone único. Conclusão: Em conclusão, a técnica de cone único resultou em menor penetração do cimento do que as outras técnicas, que não diferiram significativamente uma da outra. No entanto, a espessura do cimento foi fortemente dependente da técnica de obturação. O Termafill® demonstrou uma relação superior de GP, seguida por condensação contínua das ondas, condensação lateral e cone único. (AU)


Subject(s)
Root Canal Obturation , Microscopy, Confocal , Dental Cements , Gutta-Percha
18.
Rev. cuba. oftalmol ; 32(4): e694, oct.-dic. 2019. tab
Article in Spanish | LILACS, CUMED | ID: biblio-1099097

ABSTRACT

RESUMEN Objetivo: Identificar las características morfológicas y morfométricas de las capas de la córnea mediante microscopia confocal en pacientes diabéticos. Métodos: Se realizó un estudio descriptivo, comparativo, en 90 ojos, 60 de ellos pertenecientes a pacientes diabéticos (30 tipo 1 y 30 tipo 2) y 30 a pacientes supuestamente sanos. El estudio se realizó en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" entre enero del año 2012 y enero de 2017. Resultados: El espesor del epitelio, el estroma y el endotelio corneal fue mayor en los ojos de diabéticos tipo 1 con una media de 54,6; 506,7 y 26,7 micras respectivamente. La membrana basal epitelial se observó en el 20 por ciento de los ojos de pacientes con diabetes mellitus tipo 1, y en el 10 por ciento de los diabéticos tipo 2. El grupo de diabéticos tipo 1 mostró uno y dos plexos nerviosos por campo de microscopia confocal para el 33,3 por ciento cada uno. En los diabéticos tipo 2, predominó un plexo nervioso (40 por ciento) y en pacientes sanos predominaron 4 plexos nerviosos (66,7 por ciento). Ambos grupos de pacientes diabéticos presentaron plexos verticales tortuosos (40 por ciento y 53,3 por ciento respectivamente) y plexos nerviosos oblicuos en el grupo de pacientes supuestamente sanos (80 por ciento). Conclusiones: El estudio de la córnea por microscopia confocal en pacientes diabéticos evidencia mayor espesor corneal total y por capas, membrana basal visible, disminución del plexo nervioso sub-basal con disposición vertical y tortuosidad de las fibras(AU)


ABSTRACT Objective: To identify the morphological and morphometric characteristics of the corneal layers by confocal microscopy in diabetic patients. Methods: A descriptive and comparative study was carried out in 90 eyes, 60 of which belonged to diabetic patients (30 type 1 and 30 type 2) and 30 to supposedly healthy patients. The study was conducted at Ramón Pando Ferrer Cuban Institute of Ophthalmology, between January 2012 and January 2017. Results: Epithelial thickness, stroma and corneal endothelium was greater in the eyes of type 1 diabetics with a mean of 54.6, 506.7 and 26.7 microns, respectively. The epithelial basement membrane was observed in 20 percent of the eyes of patients with type 1 diabetes mellitus, and in 10 percent of type 2 diabetics. The group of type 1 diabetics showed one and two nerve plexuses per confocal microscopy field for 33.3 percent each. In type 2 diabetics, one nerve plexus (40 percent) predominated, while in healthy patients, four nerve plexuses (66.7 percent) predominated. Both groups of diabetic patients presented tortuous vertical plexuses (40 percent and 53.3 percent, respectively) and oblique nerve plexuses in the group of supposedly healthy patients (80 percent). Conclusions: The study of the cornea by confocal microscopy in diabetic patients showed greater total and layered corneal thicknesses, visible basal membrane, decrease in the sub-basal nerve plexus with vertical arrangement, and tortuous fiber(AU)


Subject(s)
Humans , Endothelium, Corneal/physiology , Microscopy, Confocal/methods , Diabetes Mellitus/etiology , Epidemiology, Descriptive
19.
Rev. cuba. oftalmol ; 32(4): e767, oct.-dic. 2019. tab
Article in Spanish | LILACS, CUMED | ID: biblio-1099095

ABSTRACT

RESUMEN Objetivo: Estimar los valores morfológicos y morfométricos del endotelio corneal según la cantidad de células y evaluar la concordancia interobservadores para los diferentes parámetros, considerados según los diferentes conteos celulares en adultos sin alteraciones corneales. Métodos: Se realizó una investigación observacional, descriptiva y transversal de serie de casos en el Servicio de Cirugía Refractiva del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en dos años de estudio. Después de aplicar los criterios de exclusión, la muestra quedó conformada por 200 ojos de 100 pacientes adultos sin alteraciones corneales. Se realizó microscopia endotelial de no contacto SP-3000P, para identificar los valores morfológicos (hexagonalidad y coeficiente de variabilidad) y morfométricos (densidad celular), así como el promedio del tamaño celular corneal según cantidad de células evaluadas. Resultados: Según la cantidad de células endoteliales evaluadas, no existieron diferencias significativas de las variables morfológicas y morfométricas (p> 0,05) en ambos ojos. La concordancia entre los diferentes conteos celulares según los valores de los coeficientes de correlación intraclase fueron todos altos. La concordancia interobservadores (excepto para la hexagonalidad) y los coeficientes de correlación intraclase fueron altos. Conclusiones: Los valores morfológicos y morfométricos del endotelio corneal según cantidad de células evaluadas, son similares en todos los conteos celulares. Se demuestra una buena concordancia entre los diferentes conteos celulares estudiados para los diferentes parámetros estimados(AU)


ABSTRACT Objective: To estimate the morphological and morphometric values of the corneal endothelium according to the number of cells and evaluate the interobserver concordance for the different parameters, estimated according to the different cell counts in adults without corneal alterations. Methods: An observational, descriptive and cross-sectional case series research was carried out in the Refractive Surgery Service of Ramón Pando Ferrer Cuban Institute of Ophthalmology during two years of study. After applying the exclusion criteria, the sample was made up of 200 eyes of 100 adult patients without corneal alterations. Non-contact endothelial microscopy SP-3000P was performed to identify morphological values (hexagonality and coefficient of variability) and morphometric values (cell density), as well as the average corneal cell size according to the number of cells evaluated. Results: According to the amount of endothelial cells evaluated, there were no significant differences between morphological and morphometric variables (p>0.05) in both eyes. The agreement between the different cell counts according to the values of the interclass correlation coefficients (ICC) were all high. The interobserver concordance and ICCs were also high, except for hexagonality. Conclusions: The morphological and morphometric values of the corneal endothelium, according to the number of cells evaluated, are similar in all cell counts. Good concordance between the different cell counts studied for the different estimated parameters is demonstrated(AU)


Subject(s)
Humans , Endothelium, Corneal/physiology , Epidemiology, Descriptive , Cross-Sectional Studies , Microscopy, Confocal/methods , Observational Studies as Topic
20.
Braz. dent. j ; 30(6): 555-562, Nov.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1055446

ABSTRACT

Abstract This study correlated the bond strength (BS) and dentin penetration of different sealers by push-out test and Confocal Laser Scanning Microscopy (CLSM) analysis. Forty-five root canals were prepared according to the crown-down technique and filled with gutta-percha associated to the following sealers (n=15): Endofill, AH Plus and MTA Fillapex. Five canals of each group were filled with the sealers added with 0.1% Rhodamine B dye. Next, the specimens were transversely sectioned and submitted to the push-out test (n=10) and CLSM analysis (n=5). The BS data showed the following means (MPa) and standard deviation: AH Plus (4.17±1.86); MTA Fillapex (3.13±1.96) and Endofill (2.10±1.03). Statistical analysis (two-way ANOVA, α=0.05) showed significant difference among sealers (p<0.001) and root canal thirds (p<0.001). The BS results of Endofill and MTA Fillapex were statistically similar (p>0.05), however, they were statistically different from AH Plus (p<0.001). The regional analysis of BS showed similarity between middle and apical thirds (p>0.05), and both were different from coronal portion (p<0.001). CLSM analysis verified tags formation in all groups and higher penetration of the specimens filled with AH Plus (p<0.05). The Kendall test (correlation between BS to dentin and sealer penetration into dentinal tubules) and the Pearson test (between failures pattern and sealer penetration into dentinal tubules) did not show correlation between the variables evaluated for all the tested sealers (p>0.05). AH Plus group had higher BS to dentin, and deeper tags formation than the other sealers. There was no significant correlation between BS and intratubular penetration of the tested sealers.


Resumo Este estudo correlacionou a resistência de união (RU) e a penetração de cimentos de diferentes bases à dentina radicular por meio do teste push-out e da análise por microscopia Confocal a laser (MCL). Quarenta e cinco canais radiculares foram preparados pela técnica coroa-ápice e obturados com guta-percha associada aos seguintes cimentos (n=15): Endofill, AH Plus e MTA Fillapex. Para análise por MCL da penetração dos cimentos, cinco canais foram obturados com os cimentos manipulados com Rodamina B a 0,1%. Em seguida, os espécimes foram seccionados transversalmente e submetidos ao teste de push-out (n=10) e análise por MCL (n=5). Os dados da RU apresentaram as seguintes médias (MPa) e desvio padrão: AH Plus (4,17±1,86); MTA Fillapex (3,13±1,96) e Endofill (2,10±1,03). A análise estatística (two-way ANOVA, α=0,05) mostrou diferença significativa entre os cimentos (p<0,001) e as regiões do canal radicular (p<0,001). Os resultados de RU de Endofill e MTA Fillapex foram estatisticamente semelhantes (p>0,05), no entanto, foram estatisticamente diferentes de AH Plus (p<0,001). A análise regional da RU demonstrou semelhança entre as regiões média e apical (p>0,05), e ambas foram diferentes da região cervical (p<0,001). A análise por MCL verificou a formação de tags em todos os grupos, com maior penetração nos espécimes obturados com AH Plus (p<0,05). O teste de Kendall (correlação entre RU à dentina e profundidade de penetração dos cimentos na dentina) e o teste de Pearson (correlação entre o padrão de falha e a profundidade de penetração dos cimentos na dentina) não evidenciaram correlação significativa entre as variáveis avaliadas nos cimentos testados (p<0,05). O grupo AH Plus apresentou maior RU, e formação de tags mais profundos que os outros cimentos. Não houve correlação significativa entre RU e penetração intratubular dos cimentos testados.


Subject(s)
Root Canal Filling Materials , Root Canal Therapy , Materials Testing , Microscopy, Confocal , Dentin , Epoxy Resins , Gutta-Percha
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