Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Más filtros











Intervalo de año de publicación
1.
Oper Dent ; 49(3): 262-272, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38632866

RESUMEN

OBJECTIVES: This study evaluated the influence of hydrogen peroxide (HP) with or without titanium dioxide nanotubes (TiO2) associated with violet LED (VL) regarding: a) the temperature change in the pulp chamber and facial surface; b) the decomposition of HP; and c) the cytotoxicity of the gels on pulp cells. METHODS AND MATERIALS: The experimental groups were: HP35 (35% HP/Whiteness HP, FGM); HP35+VL; HP35T (HP35+TiO2); HP35T+VL; HP7 (7.5% HP/White Class 7.5%, FGM); HP7+VL; HP7T (HP7+TiO2); and HP7T+VL. TiO2 was incorporated into the bleaching gels at 1%. Eighty bovine incisors were evaluated to determine temperature change in 8 experimental groups (n=10/group). A k-type thermocouple was used to evaluate the temperatures of the facial surface and in the pulp chamber, achieved by enabling endodontic access to the palatal surface, throughout the 30-minute session. HP decomposition (n=3) of gels was evaluated by using an automatic potentiometric titrator at the initial and 30-minute time points. Trans-enamel and trans-dentinal cell viability were assessed with a pulp chamber device as well as enamel and dentin discs (n=6), and the treatment extracts (culture medium + diffused components) were collected and applied to MDPC-23 odontoblast cells to evaluate cell viability according to the MTT test. RESULTS: A temperature increase in the pulp chamber was observed in the presence of VL at 30 minutes (p<0.05) (Mann-Whitney test). Also at 30 minutes, HP35 showed greater decomposition in the presence of VL rather than in its absence (p<0.05) (mixed linear models and the Tukey-Kramer test). HP7 provided greater cell viability than the groups treated with HP35 (p<0.05) (generalized linear models test). Cell viability was significantly lower for HP7 in the presence of VL (p<0.05). CONCLUSION: Pulpal temperature increased with VL (maximum of 1.9°C), but did not exceed the critical limit to cause pulp damage. Less concentrated HP resulted in higher cell viability, even when associated with VL.


Asunto(s)
Pulpa Dental , Peróxido de Hidrógeno , Blanqueamiento de Dientes , Animales , Blanqueamiento de Dientes/métodos , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Bovinos , Peróxido de Hidrógeno/farmacología , Supervivencia Celular/efectos de los fármacos , Blanqueadores Dentales/farmacología , Titanio , Temperatura Corporal , Cavidad Pulpar/efectos de los fármacos
2.
Eur Arch Paediatr Dent ; 24(3): 293-299, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929510

RESUMEN

PURPOSE: This study evaluated whether the presence of the salivary acquired pellicle (AP) had any effect on the dentin's darkening and on the caries arresting effect after the use of SDF + KI, in a cariogenic challenge. METHODS: Human dentin specimens were standardised, submitted to artificial caries lesion formation, and divided into five groups (n = 20): C: control group-no treatment, SDF: 38% SDF, APSDF: SDF 38% and AP, KISDF: 38% SDF and KI, and APKISDF: 38% SDF, KI and AP, that were submitted to pH cycling. Colour evaluation (CIE L*a*b* system) and surface hardness were performed before and after the treatments/pH cycling. RESULTS: SDF and APSDF groups showed no difference in colour. KISDF and APKISDF groups showed significantly different colours than the groups without KI. SDF, APSDF, and APKISDF groups had less mineral loss than C and KISDF. SDF, APSDF, and APKISDF revealed significantly greater mineral recovery, compared to KISDF and C. CONCLUSION: The AP did not influence the dentin´s colour after SDF + KI, but had a protective role in modulating the dentin´s mineral gain/loss. KI used after SDF decreased the dentin´s darkening, and did not interfere with the dentin de/remineralization process.


Asunto(s)
Caries Dental , Yoduro de Potasio , Humanos , Película Dental/patología , Color , Dentina , Fluoruros Tópicos/farmacología , Caries Dental/prevención & control , Minerales
3.
Oper Dent ; 46(3): E158-E170, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34662908

RESUMEN

This study evaluated intrapulpal concentration and hydrogen peroxide (HP) penetration at the interface of teeth restored with bioactive composites, using conventional or bulk-fill composites. Cylindrical cavities were prepared on the buccal surface of bovine incisor crowns (n=20) and restored with: resin modified glass-ionomer (RMGI, Riva Light Cure, SDI), non-bioactive bulk-fill composite (FB, Filtek Bulk, 3M Oral Care), non-bioactive conventional composite (FZ, Filtek Z350, 3M Oral Care), bioactive bulk-fill composite (AC, Activa BioActive, Pulpedent), and bioactive conventional composite (BII, Beautifil II, Shofu). After 5,000 thermal cycles, restorations (n=10) were exposed to high (35% HP [4 applications of 8 min/session-4 sessions]) or low (9.5% HP [30 min/day-14 days]) concentration bleaching protocols. After the last bleaching application, the HP intrapulpal concentration was determined. Additional teeth were restored, pigmented with rhodamine B solution, and HP penetration around the interface was observed under laser scanning confocal fluorescence microscopy (LSCFM, n=3). The presence of gaps at the interface was observed on replicas of the cross-sectioned samples under scanning electron microscopy (SEM, n=5). Data were submitted to one-way (gap analysis) and twoway analysis of variance (ANOVA; HP intrapulpal concentration) and Tukey test (α=0.05). The LSCFM images were qualitatively analyzed. The restored teeth submitted to 35% HP presented higher HP intrapulpal concentration than teeth submitted to 9.5% HP (p<0.05). No differences in HP intrapulpal concentration was observed among groups (p>0.05) when exposed to 9.5% HP. Lower HP intrapulpal concentration was observed for teeth restored with RMGI exposed to HP 35%, when compared with teeth restored with nonbioactive conventional (FZ; p=0.004) and bulk-fill composites (FB; p=0.01). No gap formation was observed at the outer enamel adhesive interface for all restorative materials. LSCFM images showed that 35% HP promoted greater degradation of rhodamine B at the enamel, except for RMGI. In this context, RMGI promoted lower HP intrapulpal concentration than non-bioactive conventional and bulk-fill composites.


Asunto(s)
Restauración Dental Permanente , Peróxido de Hidrógeno , Animales , Bovinos , Esmalte Dental , Materiales Dentales , Ensayo de Materiales
4.
Res Vet Sci ; 124: 263-269, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31003008

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) is known to be clinically responsible for reproductive failure in sows and post-weaning respiratory disease in growing piglets. During the last years, highly pathogenic PRRSV isolates have been discovered. In Italy, a PRRSV-1 subtype 1 strain (namely PR40/2014) characterized by high pathogenicity was isolated and experimental infection was characterized in terms of virological/clinical features and immune modulation (Canelli et al., 2017; Ferrari et al., 2018). The present study was performed in 4-week-old pigs experimentally infected with the highly pathogenic PRRSV1_PR40/2014 (HP-PR40) or with the conventional PRRSV1_PR11/2014 (PR11). The aim was to evaluate the interrelation between plasmatic hormones and cytokines in infected pigs compared to uninfected controls in order to address potential effects on the course of an experimental infection. The time-related changes of growth hormone (GH), insulin-like growth factor-1 (IGF-1), adiponectin, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels appear to be modulated by the infection depending on the PRRSV isolate (HP-PR40 vs. PR11). In particular, in HP-PR40 infected animals, the association between high GH levels and viremia may testify the need to block the anabolic action of GH in order to shift available energy towards the immune response. This need appeared to be delayed in PR11 animals, given the lower pathogenicity of the isolate. Adiponectin, IL-6 and TNF-α course supports the hypothesis of GH resistance mechanisms to guarantee homeostasis in HP-PR40 animals and underlines the key role of energy availability in events leading to an effective response to the virus.


Asunto(s)
Citocinas/sangre , Hormonas/sangre , Síndrome Respiratorio y de la Reproducción Porcina/metabolismo , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Animales , Femenino , Masculino , Síndrome Respiratorio y de la Reproducción Porcina/fisiopatología , Porcinos
5.
Animal ; 11(11): 1905-1912, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28318464

RESUMEN

Many fibre sources can help the adaptation of piglets at weaning, improving the growth. In this study, the effects of a dietary crude fibre concentrate (CFC) on piglet's growth was investigated. From 31 to 51 days of age, 108 weaned piglets (D×(Lw×L)), had access to two isofibrous, isoenergetic and isonitrogenous diets, supplemented with 1% of CFC (CFC group) or not (control (CON) group). From days 52 to 64 all piglets received the same starter diet. During the dietary treatment period the CFC group showed higher average daily gain, average daily feed intake and feed efficiency (P<0.001) than CON group. At 64 days of age, BW was higher in CFC group compared with CON group (P<0.001). Blood samples were collected at days 31, 38, 45 and 52 of age. From days 31 to 52 significant differences in the somatotropic axis between groups were observed. In particular, growth hormone levels were higher only at the end of the 1st week of dietary treatment (P<0.05) in CFC group animals compared with CON group animals. The IGF-I trend was similar between groups even if the IGF-I levels were higher in the CFC group than CON group 1 week after starting treatment (P<0.01). The IGF-binding protein 3 (IGFBP-3) levels were higher in the first 2 weeks of dietary treatment and lower in the 3rd week in CON group compared with CFC group (P<0.01). Specifically, the IGFBP-3 profile was consistent with that of IGF-I in CFC group but not in CON group. At the same time, an increase of leptin in CFC compared with CON group was observed (P<0.05). Piglets fed the CFC diet showed a lower diarrhoea incidence (P<0.05) and a lower number of antibiotic interventions (P<0.05) than CON diet from 31 to 51 days of age. Pig-major acute-phase protein plasma level (P<0.01) and interleukin-6 gene expression (P<0.05) were higher in CON group than CFC group at the end of 1st week of dietary treatment. In conclusion, this study showed that CFC diet influences the hormones related to energy balance enhancing the welfare and growth of piglets. Furthermore, the increase in feed intake during 3 weeks of dietary treatment improved the feed efficiency over the entire post-weaning period.


Asunto(s)
Fibras de la Dieta/farmacología , Suplementos Dietéticos , Hormona del Crecimiento/efectos de los fármacos , Porcinos/crecimiento & desarrollo , Alimentación Animal , Animales , Dieta/veterinaria , Femenino , Hormona del Crecimiento/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/efectos de los fármacos , Masculino , Porcinos/fisiología , Destete , Aumento de Peso/efectos de los fármacos
6.
Oper Dent ; 42(2): E44-E54, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27892835

RESUMEN

This study aimed to quantify the concentration of hydrogen peroxide into the pulp chamber in the presence or absence of adhesive enamel restorations and to analyze the resin-dentin interface of bleached groups. Bovine incisors (120) were randomly divided into three groups according to enamel treatment (n=40 each): (1) enamel without restoration (control); (2) enamel cavities (3 mm diameter × 1.5 mm depth) restored with a silorane-based (SB) system; or (3) enamel cavities (3 mm diameter × 1.5 mm depth) restored with a dimethacrylate-based (DB) system. Restorations were thermocycled, and all groups were submitted to one application of 35% hydrogen peroxide (HP) agent for 45 minutes and subjected to four light activation methods (n=10 each): without light, light-emitting diode (LED), LED/diode laser, or halogen light. Acetate buffer solution was placed into the pulp chamber before bleaching, and this solution was collected to spectrophotometrically determine the concentration of HP that reached the pulp chamber after bleaching. Rhodamine B was added to the HP agent and applied on additional enamel samples of each group for 24 hours. Samples were sectioned mesiodistally, and the bleaching agent was traced using confocal microscopy. According to two-way analysis of variance and Tukey test (α=0.05), the HP concentration in the pulp chamber of the control group was significantly lower than that of the SB group (p<0.05), regardless of light activation. No differences were observed between DB and SB groups and between control and DB groups, except for the DB halogen light activated group, which exhibited higher HP intrapulpal concentration (p<0.05). Confocal microscopy exhibited HP diffusion through the interface of the SB and DB restored groups as well as enamel prisms in the control group. The SB restorative system increased the HP diffusion into the pulp chamber, but HP was able to diffuse even in the absence of enamel restorations.


Asunto(s)
Resinas Compuestas/farmacología , Permeabilidad del Esmalte Dental , Cavidad Pulpar/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Cementos de Resina/farmacología , Resinas de Silorano/farmacología , Animales , Bovinos , Restauración Dental Permanente , Técnicas In Vitro , Ensayo de Materiales , Microscopía Confocal , Rodaminas , Blanqueamiento de Dientes
7.
Animal ; 10(6): 933-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27074715

RESUMEN

Nutritional stressors may cause negative effects on animal health and growth and lead to significant economic impact. Adipose tissue is an endocrine organ producing, mediators and hormones, called adipokines. They play a dynamic role in body homeostasis and in the regulation of energy expenditure, interacting with feeding behavior, hormones and growth factors. This in vitro study aimed to investigate how nutritional conditions and growth hormone (GH) can influence nitric oxide (NO) production and the expression and secretion of three important adipokines, that is leptin, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), by swine adipocytes. In our experimental model, mesenchymal stem cells from omental adipose tissue were induced to adipogenic differentiation. After differentiation, adipocytes were incubated for 24 h (T0) with DMEM/Ham's F12 (group A) or DMEM/Ham's F12 salts (group B), a DMEM/Ham's F12 formulation deprived of nutritional components. Primary adipocyte cells were also co-cultured for 4 h (T+4) or 12 h (T+12) with or without anterior pituitary slices. To stimulate GH secretion by pituitary cells, growth hormone releasing hormone at 10-8 M was added at the start of the incubation times (4 or 12 h). At T0, T+4 and T+12, NO production, leptin, IL-6 and TNF-α expression and secretion were measured. NO increased (P<0.05) up to twofold in restricted culture conditions. Deprived medium and coincubation with anterior pituitary positively influenced leptin secretion and expression. TNF-α was expressed and secreted only in deprived culture condition groups (B, B1 and B2). Nutrients availability and pituitary co-culture did not affect IL-6 expression and secretion. Our study shows an endocrine function for porcine adipocytes. In our model, adipocytes readily responded to nutritional inputs by secretion of molecules affecting energy balance. This secretion capacity was modulated by GH. Improving our knowledge of the role of adipocyte in the endocrine system, may lead to a more complete understanding of regulating energy balance in swine.


Asunto(s)
Adipocitos/metabolismo , Adipoquinas/metabolismo , Adenohipófisis/metabolismo , Porcinos/metabolismo , Adipocitos/citología , Adipogénesis , Animales , Células Cultivadas , Técnicas de Cocultivo , Femenino , Hormona del Crecimiento/metabolismo , Interleucina-6/metabolismo , Leptina/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Adenohipófisis/citología , Factor de Necrosis Tumoral alfa/metabolismo
8.
Animal ; 9(4): 629-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25483293

RESUMEN

The mechanism of action of leptin in pregnant breeding sows, in which hyperphagia is managed through dietary strategies, is yet to be clarified. The aim of this study was to monitor leptin concentrations and their interactions with lactogenic hormones in Large White×Landrace breeding multiparous sows (n=15). All sows showed a normal body condition (mean body condition score: 2.96). Blood samples were collected the day after weaning the litters, at insemination, every 15 days up to day 45 of pregnancy and every 7 days from day 46 to farrowing. At delivery, the placenta was collected for the analysis of leptin and leptin receptor expressions. Plasma leptin levels increased from the end of mid gestation (day 72) and remained high until farrowing (P<0.05). As expected, plasma prolactin (PRL), low during most of pregnancy, increased during the 2 weeks before farrowing (P<0.05), whereas progesterone levels reached plateau at 30 days of gestation and decreased at farrowing (P<0.05). Cortisol levels peaked close to farrowing (P<0.05). Leptin was expressed in the placenta, where the receptor expression analysis showed the presence of the short form but not of the long form. A positive correlation was found between leptin and PRL concentrations during mid (r=0.430; P<0.001) and late (r=0.687; P<0.001) pregnancy, and with progesterone in early pregnancy (r=0.462; P<0.05). During late gestation, a positive correlation was observed between leptin and cortisol (r=0.585; P<0.001). Our results suggested that, in restrictively fed pregnant sows, the leptin levels increased from the end of mid pregnancy to delivery, confirming the presence of leptin resistance. We showed a correlation between leptin and lactogenic hormones during different stages of pregnancy in sows. Lactogenic hormones show pregnancy-specific changes in their secretion and all may become involved in modulating leptin signal.


Asunto(s)
Leptina/sangre , Progesterona/sangre , Receptores de Leptina/sangre , Porcinos/fisiología , Animales , Femenino , Lactancia , Paridad , Embarazo
9.
Vet Microbiol ; 168(2-4): 357-64, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24332702

RESUMEN

The systemic and respiratory local immune response induced by the intradermal administration of a commercial inactivated Mycoplasma hyopneumoniae whole-cell vaccine (Porcilis(®) MHYO ID ONCE - MSD AH) in comparison with two commercial vaccines administered via the intramuscular route and a negative control (adjuvant only) was investigated. Forty conventional M. hyopneumoniae-free pigs were randomly assigned to four groups (ten animals each): Group A=intradermal administration of the test vaccine by using the needle-less IDAL(®) vaccinator at a dose of 0.2 ml; Group B=intramuscular administration of a commercially available vaccine (vaccine B); Group C=intramuscular administration of the adjuvant only (2 ml of X-solve adjuvant); Group D=intramuscular administration of a commercially available vaccine (vaccine D). Pigs were vaccinated at 28 days of age. Blood and bronchoalveolar lavage (BAL) fluid samples were collected at vaccination (blood only), 4 and 8 weeks post-vaccination. Serum and BAL fluid were tested for the presence of antibodies by ELISA test. Peripheral blood monomorphonuclear cells (PBMC) were isolated to quantify the number of IFN-γ secreting cells by ELISpot. Moreover, cytokine gene expression from the BAL fluid was performed. Total antibodies against M. hyopneumoniae and specific IgG were detected in serum of intradermally and intramuscularly (vaccine B only) vaccinated pigs at 4 and 8 weeks post-vaccination. M. hyopneumoniae specific IgA were detected in BAL fluid from vaccinated animals (Groups A and B) but not from controls and animals vaccinated with the bacterin D (p<0.05). Significantly higher gene expression of IL-10 was observed in the BAL fluid at week 8 post-vaccination in the intradermally vaccinated pigs (p<0.05). The results support that the intradermal administration of an adjuvanted bacterin induces both systemic and mucosal immune responses. Moreover, the intramuscularly administered commercial vaccines each had a different ability to stimulate the immune response both systemically and locally.


Asunto(s)
Vacunas Bacterianas/administración & dosificación , Mycoplasma hyopneumoniae/inmunología , Neumonía Porcina por Mycoplasma/inmunología , Neumonía Porcina por Mycoplasma/prevención & control , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Vacunas Bacterianas/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Inmunoglobulina A/inmunología , Inyecciones Intradérmicas , Inyecciones Intramusculares , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Leucocitos Mononucleares/inmunología , Masculino , Sus scrofa/inmunología , Porcinos/inmunología , Vacunación/métodos , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología
10.
Animal ; 6(6): 902-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22558960

RESUMEN

The effects of dietary nucleotide supplementation from 9 days of age until the end of post-weaning on piglets hormonal and immune responses and on growth performance were investigated. During lactation (days 9 to 21) and post-weaning (days 22 to 55) 10 [HBI Fomeva11 × (Large White × Landrace)] litters (n = 108 piglets) had ad libitum access to two standard diets, both supplemented with 0% (T0 group) or 0.1% (T1 group) of yeast extract nucleotides. BW of piglets at days 21 (P < 0.10), 35 and 55 (P < 0.05) was greater in T1 compared with T0. Feed intake was not different between groups (P > 0.05). Cortisol content was lower in T1 than in T0 at days 28 and 35 (P < 0.05), whereas growth hormone was lower at day 35 (P < 0.05). Levels of IGF-1 were similar across groups (P > 0.05). Nucleotide-supplemented diets increased lymphocyte subpopulation CD4-CD8+high at days 21 and 35 (P < 0.05), whereas CD4+CD8- cells were higher in T1 than in T0 at day 21 (P < 0.05). Peripheral blood mononuclear cells cytokine expression was influenced by dietary nucleotide supplementation. At weaning, interleukin (IL)-6 and IL-1ß expression was lower (P < 0.05) in T1 compared with T0, whereas the expression of interferon (IFN)-γ and IL-10 was higher (P < 0.05). At day 28, piglets in T1 showed higher values of tumor necrosis factor (TNF)-α expression than T0 and lower values of IL-10 expression (P < 0.05). Dietary nucleotide supplementation had a suppressive effect on IL-6 and IL-10 expression (P < 0.05) at day 35. On the contrary, the expression of IFN-γ, TNF-α and IL-1ß was enhanced (P < 0.05). In conclusion, these results suggest that starting a dietary nucleotide supplementation before weaning can improve the adaptive capabilities of weaned piglets to the stressors, enhancing the growth performance.


Asunto(s)
Crianza de Animales Domésticos , Animales Lactantes/crecimiento & desarrollo , Suplementos Dietéticos/análisis , Nucleótidos/administración & dosificación , Sus scrofa/crecimiento & desarrollo , Levaduras/química , Alimentación Animal/análisis , Animales , Animales Lactantes/inmunología , Animales Lactantes/fisiología , Femenino , Expresión Génica , Hormona del Crecimiento/sangre , Hidrocortisona/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Interferón gamma/sangre , Interferón gamma/metabolismo , Interleucinas/sangre , Interleucinas/metabolismo , Lactancia , Masculino , Sus scrofa/inmunología , Sus scrofa/fisiología , Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Destete
11.
J Clin Pediatr Dent ; 37(1): 53-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23342567

RESUMEN

OBJECTIVES: The aim of the present study was to evaluate hybrid layer thickness of primary molars sectioned with diamond, carbide and ultrasonic CVD burs. STUDY DESIGN: The occlusal enamel surfaces often molars were removed and superficial dentin was exposed. Three standardized cavities were prepared at mesial, central and distal exposed dentin with diamond, carbide and ultrasonic CVD burs, respectively. A self-etching adhesive system (Adhese, Ivoclar/Vivadent) was applied to prepared cavities and composite resin Z100 (3M/ESPE) was inserted according to manufacturers'instructions to hybridized dentin. Samples were light-cured and the crown was sectioned mesio-distally dividing the restored cavities in two halves which were observed under scanning electron microscopy (SEM), in order to quantitatively evaluate hybrid layer thickness (microm). Three repeated measures were performed at mesial, central and distal sites and mean values obtained were submitted to one-way analysis of variance (ANOVA). RESULTS: Data (mean +/- sd) obtained were (microm): 2.69 (0.44), 3.38 (1.23) and 2.72 (1.18)for diamond, carbide and CVD burs, respectively. No differences were observed among groups (p > 0.05). The adhesive systems promoted mechanical retention, uniform and continuous hybrid layer and resin tags formation at all dentin sites for all instruments tested. CONCLUSION: The results suggest that the minimally invasive cavities prepared with diamond, carbide and CVD for ultrasound, promoted hybrid layer formation with a similar thickness regardless the bur used.


Asunto(s)
Compuestos Inorgánicos de Carbono/química , Resinas Compuestas/química , Preparación de la Cavidad Dental/instrumentación , Materiales Dentales/química , Dentina/ultraestructura , Diamante/química , Piezocirugía/instrumentación , Resinas Acrílicas/química , Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios/química , Diseño de Equipo , Humanos , Curación por Luz de Adhesivos Dentales , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Diente Molar/ultraestructura , Cementos de Resina/química , Dióxido de Silicio/química , Propiedades de Superficie , Diente Primario/ultraestructura , Circonio/química
12.
Oper Dent ; 37(1): 63-70, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21942239

RESUMEN

This study evaluated the effects of curing modes and storage conditions on fluoride release of resin cements. In phase 1, the cumulative fluoride release rate from samples of the resin cements (Panavia F 2.0, RelyX Unicem, MaxCem, and BisCem) was quantified after 15 days storage in water (n=4). In phase 2, the fluoride release profiles from the same materials were analyzed during pH cycling (n=4). In this second phase, fluoride was measured at specific times (one, two, three, five, eight, and 15 days). Disk-shaped specimens were prepared (10 mm × 0.5 mm), and the materials were either light activated or allowed to autopolymerize. For both phases, the fluoride release was measured using a fluoride ion-specific electrode. The fluoride release in water was not affected by the curing mode of RelyX Unicem and Maxcem resin cements. Panavia F. 2.0 and BisCem resin cements, either light cured or autopolymerized modes, released higher amounts of fluoride in water than the other self-adhesive cements. In phase 2, the concentration of fluoride released decreased from the first day of pH cycling until the 15th day for all resin cements, for both curing modes, regardless of the storage solution used (demineralizing/remineralizing). The fluoride release rate during pH cycling by Panavia F 2.0 and MaxCem was not affected by the curing mode. The effect of the curing mode on fluoride ion release in water or during pH cycling was product dependent.


Asunto(s)
Cariostáticos/química , Fluoruros/química , Cementos de Resina/química , Acetatos/química , Tampones (Química) , Calcio/química , Resinas Compuestas/química , Difusión , Humanos , Concentración de Iones de Hidrógeno , Electrodos de Iones Selectos , Curación por Luz de Adhesivos Dentales/métodos , Ensayo de Materiales , Polimerizacion , Auto-Curación de Resinas Dentales/métodos , Factores de Tiempo , Trometamina/química , Agua/química
13.
Oper Dent ; 36(3): 311-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21740238

RESUMEN

This study evaluated Streptococcus mutans biofilm adhesion on the surface of three composite resins (nanofilled, Filtek Z350, 3M ESPE, Salt Lake City, UT, USA; nanohybrid, Vit-1-escence, Ultradent Products, South Jordan, UT, USA; and microhybrid, Esthet X, Dentsply, Milford, DE, USA) following different finishing and polishing techniques. Sixty standardized samples (6 × 3 mm) of each composite were produced and randomly divided into three finishing and polishing treatments (n=20): 1) control group: composite resin surface in contact with Mylar matrix strips with no finishing or polishing performed, 2) Sof-Lex aluminum oxide disc technique (3M ESPE, and 3) carbide bur finishing and Astrobrush polishing technique (Ultradent). Half the samples of each group were incubated in human saliva for 1 hour, and all the samples were subjected to S mutans (ATCC 35688) biofilm development. The mean log of CFU/mL present in the S mutans biofilm was calculated, and data were statistically analyzed by three-way analysis of variance and the Tukey test (p<0.05). Human saliva incubation promoted a significant increase of bacterial adherence on all three of the composites' surfaces, regardless of the polishing treatment performed (p<0.05). Of the three, the nanofilled composite (Filtek Z350) had the lowest bacterial adherence with each of the finishing and polishing techniques despite the presence or absence of human saliva (p<0.05). Mylar matrix strips (control group) promoted the lowest bacterial adhesion on the surface of the microhybrid and nanofilled composites in the absence of human saliva.


Asunto(s)
Adhesión Bacteriana/fisiología , Biopelículas , Resinas Compuestas/química , Materiales Dentales/química , Pulido Dental/métodos , Streptococcus mutans/fisiología , Óxido de Aluminio/química , Carga Bacteriana , Biopelículas/crecimiento & desarrollo , Compuestos Inorgánicos de Carbono/química , Pulido Dental/instrumentación , Humanos , Ensayo de Materiales , Nanocompuestos/química , Tereftalatos Polietilenos/química , Saliva/microbiología , Compuestos de Silicona/química , Propiedades de Superficie , Temperatura , Factores de Tiempo , Compuestos de Tungsteno/química , Agua/química
14.
Quintessence Int ; 41(8): p.E157-E65, 2010.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib10647
15.
Int Endod J ; 42(7): 568-75, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19467056

RESUMEN

OBJECTIVE: To evaluate the effects of intracoronal bleaching on ultimate tensile strength (UTS) of sound and etched dentine and its ultrastructure morphology. METHODOLOGY: Bovine dentine specimens with (e) or without previous etching with 37% phosphoric acid for 15 s were used for the intracoronal bleaching experiments. Teeth were randomly assigned to five treatments (n = 10): (C) control--no bleaching, (SP) sodium perborate, (CP) 35% carbamide peroxide, (25% HP) 25% hydrogen peroxide and (35% HP) 35% hydrogen peroxide. Bleaching was performed four times within a 72 h interval and afterwards, dentine pulp chamber blocks were obtained. The blocks were sectioned in 0.7 mm-thick slices and these were trimmed to reduce the inner dentine to a dumbbell shape with a cross-sectional area of 0.8 mm(2). Specimens were tested with the microtensile method (0.5 mm min(-1)) and data were analysed (two-way ANOVA-Tukey test, P < 0.05). Additional teeth were prepared for transmission electron microscopy (TEM) to evaluate dentine ultramorphology. RESULTS: The mean values of the UTS (SD) in MPa for sound dentine were: C = 48.3(8.5)a, SP = 34.6 (8.2)b, CP = 32.9 (8.9)b, 25% HP = 28.0(4.6)b, 35% HP = 26.4(6.6)b, and pre-etched dentine: Ce = 38.9(13.8)a, SPe = 31.3 (9.3)ab, CPe = 28.4 (6.2)ab, 25% HPe = 30.0 (7.9)ab, 35% HPe = 19.9(4.6)b. Significant differences between the means are indicated by the letters. TEM observations exhibited demineralization areas for all bleaching treatments. CONCLUSION: Bleaching decreased dentine UTS after treatment. Pre-etched not-bleached dentine (Ce) presented UTS similar to pre-etched bleached dentine, except for 35% HPe. The decrease of UTS of bleached dentine could be attributed to ultrastructural alterations such as loss of inorganic components.


Asunto(s)
Cavidad Pulpar/efectos de los fármacos , Dentina/efectos de los fármacos , Oxidantes/farmacología , Blanqueamiento de Dientes/métodos , Grabado Ácido Dental , Animales , Apatitas/análisis , Boratos/administración & dosificación , Boratos/farmacología , Peróxido de Carbamida , Bovinos , Colágeno/efectos de los fármacos , Colágeno/ultraestructura , Cavidad Pulpar/ultraestructura , Dentina/ultraestructura , Combinación de Medicamentos , Peróxido de Hidrógeno/administración & dosificación , Peróxido de Hidrógeno/farmacología , Microscopía Electrónica de Transmisión , Oxidantes/administración & dosificación , Peróxidos/administración & dosificación , Peróxidos/farmacología , Ácidos Fosfóricos/administración & dosificación , Distribución Aleatoria , Capa de Barro Dentinario , Estrés Mecánico , Resistencia a la Tracción , Factores de Tiempo , Desmineralización Dental/inducido químicamente , Desmineralización Dental/patología , Diente no Vital/patología , Urea/administración & dosificación , Urea/análogos & derivados , Urea/farmacología
16.
Braz Dent J ; 20(1): p.48-53, 2009.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib7921
17.
J Oral Rehabil ; 31(2): 155-9, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15009600

RESUMEN

Concern has been expressed regarding the adverse effects of peroxide-containing tooth bleaching agents on enamel surface. This study examined enamel average surface roughness before (baseline) and after an in-office bleaching protocol and investigated the influence of high concentrations of carbamide peroxide gels on its surface staining and morphology. Flat enamel surfaces were submitted to 35 and 37% carbamide peroxide or to no bleaching treatment (n = 10) and evaluated with a profilometer. Eight specimens from each group were randomly selected and immersed in a 2% methylene blue solution. Afterwards, specimens were ground into powder and prepared for the spectrophotometric analysis. Two remained specimens of each group were examined using a scanning electron microscope. Data were subjected to analysis of variance and Tukey test (P > 0.05). Baseline roughness average was statistically similar for all groups, however, 35% carbamide peroxide produced the roughest enamel surfaces. Different concentrations of carbamide peroxide produced similar staining means and enamel surface morphological alterations.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Peróxidos/efectos adversos , Blanqueamiento de Dientes/métodos , Urea/análogos & derivados , Urea/efectos adversos , Peróxido de Carbamida , Combinación de Medicamentos , Geles , Humanos , Azul de Metileno , Diente Molar , Propiedades de Superficie
18.
J Physiol Pharmacol ; 54(3): 361-70, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14566075

RESUMEN

To verify the possible role played by pig granulosa cells in the ovarian angiogenic process, we have developed a reliable in vitro system which allows the evaluation of endothelial sprouting and capillary growth in three-dimensional matrices. Granulosa cells collected from porcine follicles of different size were co-cultured with porcine aortic endothelial cells (PAEC) in a microcarrier-based fibrin gel system; after 2 and 5 days of co-culture, we determined the number and length of all endothelial sprouts; moreover, these parameters were quantified only in capillary-like structures, which were defined as continuous multicellular sprouts at least 200 microm long. In granulosa cells- PAEC co-cultures we observed an increase of angiogenic activity as compared to controls (PAEC alone). Granulosa cells from follicles of different size regulate angiogenesis differently: cells from the small follicle group significantly enhanced endothelial sprouting, while those from the large follicle group favoured mainly capillary elongation. Our observations seem therefore to suggest that the development and growth of thecal vascular bed is controlled by paracrine factors of granulosa cell origin that may induce the formation of a primitive capillary plexus during the early phases of antral follicle growth, which will be remodelled in more advanced phases of follicular development.


Asunto(s)
Técnicas de Cocultivo/métodos , Células Endoteliales/citología , Fibrina , Geles , Células de la Granulosa/citología , Neovascularización Fisiológica , Animales , Aorta/citología , Aorta/fisiología , Capilares/citología , Capilares/crecimiento & desarrollo , Movimiento Celular , Tamaño de la Célula/fisiología , Células Cultivadas , Células Endoteliales/fisiología , Femenino , Células de la Granulosa/fisiología , Porcinos , Factores de Tiempo
20.
Eur Urol ; 41(3): 246-9, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12180223

RESUMEN

OBJECTIVE: Evaluate the predictive value of a combination of IPSS, uroflowmetry and ultrasound determination of residual urine volume in the determination of bladder outflow obstruction (BOO) and in predicting treatment outcome. METHODS: Forty-five out of a group of 60 BPH symptomatic patients were included. Preoperative evaluation: urine culture, PSA, uroflowmetry with sonographic measurement of post-void residual urine, DRE, IPSS with quality of life questions and pressure-flow study. Selection criteria for surgery were IPSS > 16 and Qmax < 10 ml/s. Transurethral resection of the prostate was performed in these patients; the control visit was performed at 3 months. Treatment success was defined as Qmax above 15 ml/s, residual urine of less than 100 ml, a 50% reduction in IPSS and absence of urinary retention. RESULTS: Urodynamic abnormalities were found in 42 patients (93.3%): 19 had detrusor instability, 5 patients showed impaired contractility, 37 patients had proven BOO, and 8 patients were unobstructed or mildly obstructed. The overall success rate was 86% when measured by the IPSS. Its preoperative value was 16.9, and dropped significantly to 4 (P = 0.005). The score improved significantly after surgery only in the obstructed group compared to the non-obstructed group (P = 0.001), however preoperative IPSS did not correlate with objective treatment results. CONCLUSIONS: A high proportion of patients successfully operated (71.1%) had a combination of IPSS > 16 and Qmax < 10 ml/s, although BOO could not be accurately predicted with non-invasive methods alone. Patients with no or mild infravesical obstruction had only minimal improvement of IPSS and uroflowmetry following surgery.


Asunto(s)
Hiperplasia Prostática/diagnóstico , Urodinámica , Anciano , Humanos , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Hiperplasia Prostática/fisiopatología , Hiperplasia Prostática/cirugía , Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico , Obstrucción del Cuello de la Vejiga Urinaria/fisiopatología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA