[Show abstract][Hide abstract] ABSTRACT: Multi-specie biofilms are highly resistant to antimicrobials due to cellular interactions found in them. The purpose of this study was to evaluate, by confocal laser scanning microscopy, the biofilm dissolution effectiveness of different irrigant solutions on biofilms developed on infected dentin in situ.
[Show abstract][Hide abstract] ABSTRACT: The present study evaluated the antimicrobial in vitro effects of the salivary proteins lactoferrin and lysozyme on microorganisms involved in the carious process, obtaining their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Streptococcus mutans (ATCC 25175) and Lactobacillus casei (ATCC 7469) were submitted to broth macrodilution of lysozyme at 80 mg/mL and lactoferrin at 200 mg/mL. The tubes were read in a spectrophotometer after they had been incubated at 37 °C for 18 h, in a carbon dioxide chamber, in order to read the MIC. A new subculture was carried on agar plates to obtain the MBC. The agar diffusion method was also tested, using BHI agar with 100 µL of the standardized microbial inocula. Filter-paper disks soaked in 10 µL of the solutions lactoferrin (200 µg/mL) and lysozyme (80 µg/mL) were placed on the agar surface. Inhibition halos were not observed on the plates, showing the absence of the antimicrobial effects of these proteins in this method. The bactericidal and bacteriostatic effects of lysozyme on L. casei were 50.3 mg/mL and 43.1 mg/mL respectively. The bactericidal and bacteriostatic effects on S. mutans were 68.5 mg/mL and 58.7 mg/mL. Lactoferrin did not induce any inhibitory effects on any microorganism, even in the concentration of 200 mg/mL. There was not a synergic antimicrobial effect of proteins, when they were tested together, even in the concentration of 42.8 mg/mL of lysozyme and 114 mg/mL of lactoferrin (the highest values evaluated). S. mutans and L. casei were only inhibited by lysozyme, not affected by lactoferrin and by the synergic use of both proteins.
[Show abstract][Hide abstract] ABSTRACT: Introduction: The purpose of this study was to evaluate the effects of ultrasonic activation on the filling quality (in-tratubular sealer penetration, interfacial adaptation, and presence of voids) of 4 epoxy resin–based sealers. Methods: Eighty-four extracted human canines were divided into 4 groups (n = 20) according to the sealer used to obturate the root canals instrumented with F5 Pro-Taper instruments (50/05) (Dentsply Maillefer, Ballaigues, Switzerland). The canals were filled by the lateral compac-tion technique. Previously, the sealers were labeled with rhodamine B dye to allow analysis under a confocal micro-scope. At the time of obturation, the specimens were divided again into 2 groups (n = 10) according to the ultra-sonic activation of the sealers: ultrasonically activated and nonultrasonically activated groups. All samples were sectioned at 2, 4, and 6 mm from the apex. The percentages of voids, gaps, and dentinal sealer penetration segments of the canal were analyzed. Results: Regarding the sealer penetration segments, there was a significant increase for the AH Plus (Dentsply Maillefer), Acroseal (Specialit es Septodont, Saint Maur-des-Foss es, France), and Sealer 26 (Dentsply Maillefer) at the 4-mm level and the AH Plus and Sealer 26 at the 6-mm level with ultrasonic activation (P < .05). Concerning the gaps, the ultrasonic activation promoted a smaller presence for all sealers at the 4-and 6-mm levels (P < .05). No statistical significant differences were found for the percentages of voids (P < .05). Conclusions: The use of ultrasonic activation of an epoxy resin–based sealer promoted greater dentinal sealer pene-tration and less presence of gaps. (J Endod 2014;-:1–5) Key Words
Journal of Endodontics 01/2014; 40(7):964-968. · 2.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objetivo. El propósito de este estudio fue comparar el material sólido extruido por el foramen apical usando las técnicas manuales Step Back, Oregon y las rotatorias, Sistema K3 Endo, Sistemas Protaper y sistema F.K.G. RaCe. Material y métodos. Sesenta y cinco dientes unirradiculares fueron utilizados siendo 15 para cada uno de los grupos. El material extruído en las diferentes técnicas fue recogido en papel de filtro (Whatman ®) sometidos a secado en estufa y pesado en balanza digital de alta precisión. A través del test ANOVA se observó la diferencia existente entre los diferentes grupos estudiados y el test paramétrico de Tukey fue aplicado para el análisis comparativo de los grupos entre sí. Resultados. El análisis de los resultados mostró extrusión de material por el foramen en todas las técnicas testadas.siendo que Step Back promovió la mayor cantidad de material extruido siendo significante en relación a las demás que fueron equivalentes estadísticamente. Conclusiones. No fue observada diferencia significativa entre la técnica de Oregon y las rotatorias siendo que entre estas el sistema K3 Endo proporcionó el menor índice de extrusión. PALABRAS CLAVE Extrusión apical; Endodoncia; Técnicas rotatorias; Técnicas manuales. ABSTRACT Objective. The purpose of this study was to conpare the solid material extruded through the apical foramen using manual techniques Step Back, Oregon and rotary systems: K3 Endo, ProTaper and FKG RaCe. Material and methods. Sixty-five single-root teeth were used with 15 for each of the groups. The extruded material of different techniques was collected in filter paper (Whatman ®) submitted to oven drying and weighing in high precision digital scale. Through ANOVA test was observed the difference between the different studied groups and the Tukey parametric test was applied to the comparative analysis of the groups together. Results. The analysis of the results showed extrusion material through the foramen in all techniques. Step Back promoted the most significant being extruded material in relation to the others that were statistically equivalent. Conclusions. No significant difference was observed between the technique of Oregon and rotary systems; among these being that K3 Endo system provided the lowest rate of extrusion.
[Show abstract][Hide abstract] ABSTRACT: The objective of this study was to analyze the genotypic diversity, frequency of serotypes and the detection of mutacins from Streptococcus mutans isolates in caries-free and caries-active individuals.A total of 260 S. mutans isolated from 28 individuals with and without dental caries were subjected to AP-PCR and PCR screening of glucosyltransferase B, mutacin and serotype genes, which showed the presence of. 70 different genotypes. There was no statistically significant association between the presence of genes for serotypes and mutacins with dental caries. However, there was a statistically significant and a strong association between the higher genotypic diversity in the subjects with caries (r = 0.72, p = 0.001). There was an increase in the number of genotypes with increasing age (p <0.01).
Brazilian Archives of Biology and Technology 04/2013; 56(2):241-248. · 0.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Abstract Objectives. To evaluate if the incorporation of antimicrobial compounds to chelating agents or the use of chelating agents with antimicrobial activity as 7% maleic acid and peracetic acid show similar disinfection ability in comparison to conventional irrigants as sodium hypochlorite or iodine potassium iodide against biofilms developed on dentin. Materials and methods. The total bio-volume of live cells, the ratio of live cells and the substratum coverage of dentin infected intra-orally and treated with the irrigant solutions: MTAD, Qmix, Smear Clear, 7% maleic acid, 2% iodine potassium iodide, 4% peracetic acid, 2.5% and 5.25% sodium hypochlorite was measured by using confocal microscopy and the live/dead technique. Five samples were used for each irrigant solution. Results. Several endodontic irrigants containing antimicrobials as clorhexidine (Qmix), cetrimide (Smear Clear), maleic acid, iodine compounds or antibiotics (MTAD) lacked an effective antibiofilm activity when the dentin was infected intra-orally. The irrigant solutions 4% peracetic acid and 2.5-5.25% sodium hypochlorite decrease significantly the number of live bacteria in biofilms, providing also cleaner dentin surfaces (p < 0.05). Conclusions. Several chelating agents containing antimicrobials could not remove nor kill significantly biofilms developed on intra-orally infected dentin, with the exception of sodium hypochlorite and 4% peracetic acid. Dissolution ability is mandatory for an appropriate eradication of biofilms attached to dentin.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the pH, calcium ion release, setting time, and solubility of white mineral trioxide aggregate (WMTA) and white Portland cement (WPC) combined with the following radiopacifying agents: bismuth oxide (BO), calcium tungstate (CT), and zirconium oxide (ZO).
Fifty acrylic teeth with root-end filling material were immersed in ultrapure water for measurement of pH and calcium release (atomic absorption spectrophotometry) at 3, 24, 72, and 168 hours. For evaluation of setting time, each material was analyzed according to the American Society for Testing and Materials guidelines 266/08. The solubility test was performed according to American National Standards Institute/American Dental Association specification no. 57/2000. Solubility, setting time, and pH values were compared by using analysis of variance and Tukey test, and the values of calcium release were compared by the Kruskal-Wallis and Miller tests. The significance level was set at 5%.
The pH and calcium release were higher at 3 and 24 hours. WPC was the material with the higher values for both properties. WMTA had the greatest solubility among all materials (P < .05). All radiopacifiers increased the setting time of WPC, and WMTA had the shortest setting time among all materials (P < .05).
All materials released calcium ions. Except for WPC/CT at 168 hours, all materials promoted an alkaline pH. On the basis of the obtained results, ZO and CT can be considered as potential radiopacifying agents to be used in combination with Portland cement.
Journal of endodontics 03/2012; 38(3):394-7. · 2.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: From an academic standpoint, the university format, in general, has been nurturing a "paradigm of expertise" and, consequently, the relationship between specialties has declined. The upshot is that recent college dental graduates have adopted a clinical performance focusing on system parts and their specificities, in detriment to a more comprehensive view of the mouth and of the patient as a whole, with his/her vital, emotional and individual attributes. An interaction between the several different areas of human knowledge is needed imminently to decrease the dichotomy in professional behavior, because the demand for professionals and dental patients interested in a more comprehensive approach are increasing day by day. Patients want to know: "What, in fact, is behind the etiological extrinsic and intrinsic factors that maintain neuropathic pain, recurrent thrush, or persistent halitosis," among other questions, "even under the care of a dentist?" or "Why is this disease affecting me?" There are several issues composing the paradigm of salutogenesis: What are the essential aspects that constitute a healthy individual, overlapping the usual investigation: How to destroy, avoid and quell the pathological agents? A proposed approach is based on salutogenesis, which examines such issues. According to this approach, anthroposophical dentistry includes determinant factors, determinants of health, basic research and the development of oral health promotion, thus connecting dental academia with integrative thinking, while also complementing and gathering information that subsidizes basic research with the primordial concepts on laws governing the parameters involved in the vital processes of nature.
Brazilian oral research 01/2012; 26 Suppl 1:57-63.
[Show abstract][Hide abstract] ABSTRACT: The aim of the study was to evaluate the radiopacity, solubility, flow, film thickness, setting time, and adaptation to the root canal walls of 3 epoxy resin-based sealers: AH Plus, Acroseal, and Adseal.
Physical tests were performed following American National Standards Institute/American Dental Association's requirements. For interfacial adaptation analysis, 30 maxillary canines were shaped by using ProTaper instruments. The specimens were divided into 3 groups (n = 10): group 1, AH Plus; group 2, Acroseal; and group 3, Adseal. The sealers were mixed with rhodamine B dye, and the canals were filled by using the lateral compaction technique. The percentage of gaps and voids area was calculated at 2, 4, and 6 mm levels from the apex. Statistical evaluation was performed by using analysis of variance for physical analysis and nonparametric Kruskal-Wallis and Dunn tests for interfacial adaptation (P < .05).
No statistical differences were found for adaptation, percentage of voids, solubility, flow, and film thickness among the sealers (P > .05). AH Plus was significantly more radiopaque (P < .05). For the setting time, there were statistical differences among all the studied sealers (P < .05).
AH Plus, Acroseal, and Adseal presented similar root canal adaptation, solubility, flow, and film thickness. Statistical differences were found for radiopacity and setting time (P < .05).
Journal of endodontics 10/2011; 37(10):1417-21. · 2.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study evaluated the caries risk of asthmatic patients on the basis of mutans streptococci (MS) and lactobacilli levels in saliva samples as well as the index of oral hygiene and dental caries (DMFT index). The study population was composed of 80 asthmatic children, aged 3-15 years, who use specific medication, and 80 matched, healthy control children. The parents were interviewed about oral health-related factors. The World Health Organization criteria were used for dental examinations. The Köhler and Bratthal methodology was used to detect salivary MS levels and dilutions of saliva were done for lactobacilli counting. No differences between asthma and control groups were observed for caries prevalence in children aged 3-6 and 7-10 years, except in severe cases in the younger group. However, higher caries prevalence for permanent dentition was observed in 11- to 15-year-old asthmatic children. An increased dental biofilm was observed in the asthma group, as well as salivary levels of MS. No differences were observed in levels of lactobacilli. No statistical correlations were found between medication, frequency of treatment, method of consumption and caries experience, dental biofilm and salivary levels of MS or lactobacilli. However, there was a correlation between MS levels and treatment duration. The logistic regression revealed that MS level is an important risk factor for increased caries experience. Asthma should be evaluated as a risk factor for caries experience because it can increase the levels of MS and the dental biofilm.
Caries Research 08/2011; 45(4):386-92. · 2.51 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the biofilm dissolution and cleaning ability of different irrigant solutions on intraorally infected dentin.
One hundred twenty bovine dentin specimens were infected intraorally by using a removable orthodontic device. Thirty samples were used for each irrigant solution: 2% chlorhexidine and 1%, 2.5%, and 5.25% sodium hypochlorite (NaOCl). The solutions were used for 5, 15, and 30 minutes and at 2 experimental volumes, 500 μL and 1 mL. The samples were stained by using acridine orange dye before and after the experiments and evaluated by using a confocal microscope. The percentage of biofilm, isolated cells, and noncolonized dentin was measured by using a grid system. Differences in the reduction or increase of the studied parameters were assessed by using nonparametric methods (P < .05).
The higher values of biofilm dissolution and noncolonized dentin were found in the 30-minute NaOCl group and in the 5-minute and 15-minute groups of 5.25% NaOCL. The use of 2% chlorhexidine solution did not improve the biofilm dissolution or increase the cleaning of the dentin in comparison with the NaOCl solutions (P < .05).
Two percent chlorhexidine does not dissolve the biofilms. Thirty minutes of NaOCl are necessary to have higher values of biofilm dissolution and to increase the cleaning of the dentin independently of the concentration in comparison with the 5-minute and 15-minute contact times.
Journal of endodontics 08/2011; 37(8):1134-8. · 2.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study investigated the mechanical properties of glass ionomer cements (GICs) combined with propolis as a natural antimicrobial substance.
Typified green propolis, as an ethanolic extract (EEP) or in the lyophilized form (powder), was incorporated to specimens of Ketac Fil Plus, ChemFlex and Ketac Molar Easymix GICs. For each test, 8 specimens of each material were prepared. For water sorption and solubility tests, specimens were subjected to dehydration, hydration and redehydration cycles until a constant mass was obtained for each step. Measurements were recorded using a digital balance of 10-4 g precision. For the diametral tensile strength test, specimens were tested in a universal test machine at 0.5 mm/min crosshead speed after 24 h storage in deionized water. Data were evaluated by one-way ANOVA and Tukey's tests (p<0.05).
The addition of propolis to GIC clearly increased water sorption compared to pure material. Solubility was material-dependent and was not clearly evident. For the diametral tensile strength test, association with propolis altered negatively only Chemflex.
It may be concluded that incorporation of propolis to GICs alters some properties in a material-dependent condition.
Journal of applied oral science: revista FOB 04/2011; 19(2):100-5. · 0.39 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study aimed to investigate the dental caries status and salivary properties in 3- to 15-year-old children/adolescents.
The sample was split in two groups: asthma group (AG), composed of 65 patients who attended Public Health Service; asthma-free group (AFG), composed of 65 nonasthmatic children/adolescents recruited in two public schools. Stimulated salivary samples were collected for 3 min. Buffering capacity and pH were ascertained in each salivary sample. A single trained and calibrated examiner (kappa = 0.98) performed the dental caries examination according to WHO criteria.
The AFG showed salivary flow rate (1.10 ± 0.63 mL/min) higher (P = 0.002) than AG (0.80 ± 0.50 mL/min). An inverse relationship was observed between asthma severity and salivary flow rate (Phi coefficient, rφ: 0.79, P = 0.0001). Children with moderate or severe asthma showed an increased risk for reduced salivary flow rate (OR: 17.15, P < 0.001). No association was observed between drug use frequency (P > 0.05) and drug type (P > 0.05) with salivary flow rate. Buffering capacity was similar in both groups. No significant differences were encountered in dental caries experience between AFG and AG groups.
Although asthma can cause reduction in flow rate, the illness did not seem to influence dental caries experience in children with access to proper dental care.
International Journal of Paediatric Dentistry 02/2011; 21(3):185-91. · 0.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: PURPOSE: Saliva contains both specific and non-specific protective factors of the immune system, such as antimicrobial proteins, which can inhibit the adhesion and viability of cariogenic microorganisms. The association between caries experience/activity and the electrophoretic profiles of salivary proteins lactoferrin and lysozyme was evaluated. METHODS: Eighty 12-year-old students from public schools in Londrina, PR, Brazil, were selected and divided into two groups: Group A with decayed teeth and Group B with caries-free teeth. The parent/guardian of each child signed a consent form and filled out a questionnaire regarding the oral and systemic health of his/her child. A clinical examination to diagnose the presence or absence of dental caries, by means of the DMFT index, was conducted. A total of 1 mL of saliva was collected for protein analysis using a polyacrylamide gel electrophoresis (SDS-PAGE). RESULTS: A total of 58.8% of the children were caries-inactive; in contrast, 63.3% showed caries experience. There was a slight association between lysozyme concentrations and DMFT. Lactoferrin was positively correlated with both DMFT and restored teeth. CONCLUSION: The quantification of lactoferrin and lysozyme enabled an assessment of possible associations with caries status, thus improving the understanding of the biological and etiological aspects of caries.