RESUMO
Sepsis is one of the leading causes of mortality in intensive care units besides causing profound alterations in the brain. One of the structures notably affected during sepsis is the hypothalamus, resulting in important physiopathological consequences. Recently, we provided evidence that the presence of neuroinflammation, oxidative stress, and apoptosis in the hypothalamus of septic rats, is accompanied by impairment of arginine vasopressin (AVP) secretion. We had also demonstrated that sepsis survivor animals present attenuated AVP secretion after osmotic challenge, suggesting a persistent inflammation in the hypothalamus. However, the long-term course of inflammation in the hypothalamus remains unclear. Thus, we induced sepsis by cecal ligation and puncture (CLP) in Wistar rats and, five days after sepsis induction, the hypothalamus of each animal was collected for analysis. Nonmanipulated animals (naive) were used as controls. We found that CLP-induced morphological alterations in microglial cells are accompanied by an increase in Iba-1 immunoreactivity. Moreover, we observed enhanced expression of NF-κB and CREB transcription factors, which are well known to modulate the immune response. Additionally, we found that phosphorylation of GSK3α/ß (a kinase upstream to the CREB signaling pathway) was increased, as well as COX-2, iNOS, and IL-6 that are canonic inflammatory proteins. Thus, our results indicated the presence of sustained activation of resident glial cells that may result in neuroinflammation and cholinergic neurotransmission disruptions in the hypothalamus.
Assuntos
Acetilcolinesterase/metabolismo , Microambiente Celular/fisiologia , Hipotálamo/metabolismo , Mediadores da Inflamação/metabolismo , Microglia/metabolismo , Sepse/metabolismo , Animais , Ativação Enzimática , Hipotálamo/patologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Microglia/patologia , Ratos , Ratos Wistar , Sepse/patologiaRESUMO
The impairment in arginine vasopressin (AVP) secretion during sepsis is described in clinical and experimental studies and has been associated with oxidative stress, apoptosis, and diminished activation of hypothalamic neurons. Few studies have, however, assessed these abnormalities in sepsis survivors. Here we performed two sets of experiments on Wistar rats that had been subjected to sepsis by cecal ligation and puncture (CLP) or nonmanipulated (naive) as control. In the first set, tissues and blood were collected from survivor rats 10 days after CLP to quantify hypothalamic Bcl-2, cleaved caspase- 3 and synaptophysin content, and bacterial load. In the second set, survivor rats were submitted to an acute osmotic stimulus (hypertonic saline), and after 30 minutes the water intake and AVP secretion were analyzed. The sepsis-surviving rats did not show bacterial load in tissues, but their hypothalamic synaptophysin and Bcl-2 levels were decreased, and the cleaved caspase- 3 level was increased when compared with the control group. However, AVP secretion was significantly attenuated in the CLP survivor animals submitted to an acute osmotic stimulus. These results suggest that the persistent AVP impairment in sepsis survivor animals may be due to a hypothalamic dysfunction associated with a synaptic deficit and decreased anti-apoptotic protein expression. This article is protected by copyright. All rights reserved.
RESUMO
Besides their well-established endocrine roles, vasopressin and oxytocin are also important regulators of immune function, participating in a complex neuroendocrine-immune network. In the present study, we investigated whether and how vasopressin and oxytocin could modulate lipopolysaccharide (LPS)-induced nitric oxide (NO) production in a well-established model of experimental endotoxaemia. Male Wistar rats were previously treated i.v. with vasopressin V1 or oxytocin receptor antagonists and then received either an i.v. LPS injection to induce endotoxaemia or a saline imjection as a control. The animals were divided into two groups: in the first group, blood was collected at 2, 4 and 6 h after LPS injection; in the second group, mean arterial blood pressure (MABP) and heart rate (HR) were recorded over 6 h. Plasma vasopressin and oxytocin values were higher in LPS- compared to saline-injected animals at 2 and 4 h but returned to basal levels at 6 h. NO levels exhibited an opposite pattern, showing a progressive increase over the entire period. The previous administration of a vasopressin V1 receptor antagonist significantly reduced NO plasma concentrations at 2 and 4 h but not at 6 h. By contrast, oxytocin receptor agonist pre-treatment had no effect on the NO plasma concentration. In relation to MABP, previous treatment with vasopressin V1 receptor antagonist reversed the LPS-induced hypotension at 4 h, although this was not the case for oxytocin antagonist-treated animals. None of the antagonists affected HR. Our findings indicate that vasopressin (but not oxytocin) has effects on NO production during endotoxaemia in rats, although they do not lend support to the proposed anti-inflammatory actions of vasopressin during endotoxaemia.
Assuntos
Endotoxemia/sangue , Hipotensão/sangue , Óxido Nítrico/sangue , Ocitocina/sangue , Neuro-Hipófise/metabolismo , Vasopressinas/sangue , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Arginina Vasopressina/análogos & derivados , Arginina Vasopressina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hipotensão/induzido quimicamente , Lipopolissacarídeos/antagonistas & inibidores , Masculino , Ratos , Receptores de Ocitocina/antagonistas & inibidores , Fatores de TempoRESUMO
OBJECTIVE: To assess disability in patients with venous leg ulcers treated with compression therapy with Unna's boot. METHOD: A descriptive analytic case control study was conducted from June 2010 to May 2011 in an outpatient wound care clinic in interior Brazil. Fifty patients of both sexes, aged 18 years or above, who had had a venous leg ulcer for more than 1 year and a Doppler ankle-brachial index of 0.8-1.0 were selected for the study. Patients were treated with wound dressings and Unna's boot. Disability was assessed using the 20-item Stanford Health Assessment Disability Scale (HAQ-20). Statistical analysis was performed using the Student's t-test, the Kruskal-Wallis test and the chi-square test of independence, all at a significance level of 0.05 (p < 0.05). RESULTS: The mean overall HAQ score at inclusion (baseline) was 2.98, indicating impaired functional capacity. After 8 and 12 months of compression treatment with Unna's boot, the mean overall HAQ scores were 1.35 and 1.0, respectively, indicating good functional capacity. CONCLUSION: Patients with venous leg ulcer reported severe difficulty or serious disability in their daily functioning at baseline; after 8 months of treatment with Unna's boot, these patients were able to perform activities of daily living.
Assuntos
Atividades Cotidianas , Úlcera Varicosa , Índice Tornozelo-Braço , Bandagens , Estudos de Casos e Controles , Humanos , Úlcera da Perna/terapia , Pressão , Úlcera Varicosa/terapiaRESUMO
BACKGROUND: Acinetobacter baumannii has evolved from an opportunistic pathogen into a common and persistent nosocomial bacterium capable of causing severe infections during endemic and epidemic periods. METHODS: The study period extended from January 1999 to December 2011 and involved patients hospitalized at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, Jalisco, Mexico. From each patient, a single isolate was obtained, and a total of 3,680 unique isolates were collected. Susceptibility tests were performed according to the guidelines of the Clinical and Laboratory Standards Institute. RESULTS: A. baumannii has disseminated throughout the Hospital Civil de Guadalajara, Fray Antonio Alcalde, since 1999. A. baumannii isolates obtained from patients treated in the adult intensive care unit represent the majority of the isolates that have been collected. In addition, A. baumannii was isolated from the adult neurosurgical ward and the adult internal medicine ward, and these isolates were frequently obtained from secretions. A persistent decrease in the susceptibility of A. baumannii isolates to meropenem (92% in 1999 to 12% in 2011), imipenem and amikacin has been observed. CONCLUSIONS: A. baumannii became an endemic nosocomial pathogen during the study period at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, and has exhibited a persistent decrease in susceptibility to all categories of antimicrobial agents over the past 13 years.
Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/efeitos dos fármacos , Amicacina/farmacologia , Antibacterianos/farmacologia , DNA Bacteriano/análise , Eletroforese em Gel de Campo Pulsado , Humanos , Imipenem/farmacologia , Unidades de Terapia Intensiva , Meropeném , México , Testes de Sensibilidade Microbiana , Atenção Terciária à Saúde , Tienamicinas/farmacologiaRESUMO
AIM: The aim was to assess the characteristics and outcomes of infections affecting the structures of carious primary molars. MATERIALS AND METHODS: Forty primary molars were used and classified according to the following clinical situation: With profound caries lesion, with bone loss at the furcation region, with perforation of the pulp chamber floor, and residual roots. The teeth were demineralized, cut, and stained with both haematoxylin-eosin and Brown and Brenn staining techniques. Assessment was performed using optical microscopy. RESULTS: Statistical analysis of the data by means of the Chi-square test suggests that there was a significant relationship (P<0.001) between the intensity and localization of infection and the level of destruction of dental structures. A significant difference was also observed in the intensity and localization of infection between the groups regarding crown, furca, and root (P<0.001). CONCLUSION: More intense and profound the infection, more severe is the dental destruction. The groups of residual roots showed the most severe bacterial infection compared to other groups.
Assuntos
Cárie Dentária/microbiologia , Dente Molar/microbiologia , Dente Decíduo/microbiologia , Adolescente , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/patologia , Carga Bacteriana , Criança , Pré-Escolar , Corantes , Cárie Dentária/patologia , Exposição da Polpa Dentária/microbiologia , Exposição da Polpa Dentária/patologia , Necrose da Polpa Dentária/microbiologia , Necrose da Polpa Dentária/patologia , Amarelo de Eosina-(YS) , Feminino , Corantes Fluorescentes , Hematoxilina , Humanos , Hiperemia/microbiologia , Hiperemia/patologia , Masculino , Dente Molar/patologia , Granuloma Periapical/microbiologia , Granuloma Periapical/patologia , Abscesso Periodontal/microbiologia , Abscesso Periodontal/patologia , Pulpite/microbiologia , Pulpite/patologia , Coroa do Dente/microbiologia , Coroa do Dente/patologia , Raiz Dentária/microbiologia , Raiz Dentária/patologia , Dente Decíduo/patologiaRESUMO
In a previous study, we reported that the short-term treatment with celecoxib, a non-steroidal anti-inflammatory drug (NSAID) attenuates the activation of brain structures related to nociception and does not interfere with orthodontic incisor separation in rats. The conclusion was that celecoxib could possibly be prescribed for pain in orthodontic patients. However, we did not analyze the effects of this drug in periodontium. The aim of this follow-up study was to analyze effects of celecoxib treatment on recruitment and activation of osteoclasts and alveolar bone resorption after inserting an activated orthodontic appliance between the incisors in our rat model. Twenty rats (400-420 g) were pretreated through oral gavage with celecoxib (50 mg/kg) or vehicle (carboxymethylcellulose 0.4%). After 30 min, they received an activated (30 g) orthodontic appliance, set not to cause any palate disjunction. In sham animals, the appliance was immediately removed after introduction. All animals received ground food and, every 12 h, celecoxib or vehicle. After 48 h, they were anesthetized and transcardiacally perfused through the aorta with 4% formaldehyde. Subsequently, maxillae were removed, post-fixed and processed for histomorphometry or immunohistochemical analyses. As expected, incisor distalization induced an inflammatory response with certain histological changes, including an increase in the number of active osteoclasts at the compression side in group treated with vehicle (appliance: 32.2 ± 2.49 vs sham: 4.8 ± 1.79, P<0.05) and celecoxib (appliance: 31.0 ± 1.45 vs sham: 4.6 ± 1.82, P<0.05). The treatment with celecoxib did not modify substantially the histological alterations and the number of active osteoclasts after activation of orthodontic appliance. Moreover, we did not see any difference between the groups with respect to percentage of bone resorption area. Taken together with our previous results we conclude that short-term treatment with celecoxib can indeed be a therapeutic alternative for pain relieve during orthodontic procedures.
Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Osteoclastos/efeitos dos fármacos , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Técnicas de Movimentação Dentária , Animais , Reabsorção Óssea , Celecoxib , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Seguimentos , Modelos Animais , Aparelhos Ortodônticos , Osteoclastos/citologia , Dor/tratamento farmacológico , Pirazóis/uso terapêutico , Ratos , Sulfonamidas/uso terapêutico , Fatores de TempoRESUMO
Sepsis induces production of inflammatory mediators such as nitric oxide (NO) and causes physiological alterations, including changes in body temperature (Tb). We evaluated the involvement of the central NO-cGMP pathway in thermoregulation during sepsis induced by cecal ligation and puncture (CLP), and analyzed its effect on survival rate. Male Wistar rats with a Tb probe inserted in their abdomen were intracerebroventricularly injected with 1 microL NG-nitro-L-arginine methyl ester (L-NAME, 250 microg), a nonselective NO synthase (NOS) inhibitor; or aminoguanidine (250 microg), an inducible NOS inhibitor; or 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ, 0.25 microg), a guanylate cyclase inhibitor. Thirty minutes after injection, sepsis was induced by cecal ligation and puncture (CLP), or the rats were sham operated. The animals were divided into 2 groups for determination of Tb for 24 h and assessment of survival during 3 days. The drop in Tb seen in the CLP group was attenuated by pretreatment with the NOS inhibitors (p < 0.05) and blocked with ODQ. CLP rats pretreated with either of the inhibitors showed higher survival rates than vehicle injected groups (p < 0.05), and were even higher in the ODQ pretreated group. Our results showed that the effect of NOS inhibition on the hypothermic response to CLP is consistent with the role of nitrergic pathways in thermoregulation.
Assuntos
Regulação da Temperatura Corporal/fisiologia , GMP Cíclico/fisiologia , Óxido Nítrico/fisiologia , Sepse/mortalidade , Sepse/fisiopatologia , Animais , Temperatura Corporal/fisiologia , Ceco , Guanidinas/administração & dosagem , Injeções Intraperitoneais , Ligadura , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/fisiologia , Punções , Distribuição Aleatória , Ratos , Ratos Wistar , Sepse/enzimologia , Sepse/microbiologia , Taxa de Sobrevida/tendênciasRESUMO
Non-steroidal anti-inflammatory drugs (NSAIDs) have been used for pain relief in orthodontics, but clinical studies reported that they may reduce tooth movement (TM). By other side, TM seems to activate brain structures related to nociception, but the effects of NSAIDs in this activation have not been studied yet. We analyzed the effect of short-term treatment with acetaminophen or celecoxib in the separation of rat upper incisors, as well as in neuronal activation of the spinal trigeminal nucleus, following tooth movement. Thirty rats (400-420 g) were pretreated through oral gavage (1 ml/dose) with acetaminophen (200mg/kg), celecoxib (50mg/kg) or vehicle (carboxymethylcellulose 0.4%). After 30 min, they received an activated (30 g) orthodontic appliance for TM. In controls, this appliance was immediately removed after its introduction. Rats received ground food, and every 12h, one of the drugs or vehicle. After 48 h, they were anesthetized, maxilla was radiographed, and were perfused with 4% paraformaldehyde. Brains were further processed for Fos immunohistochemistry. TM induced incisor distalization (p<0.05) and neuronal activation of the spinal trigeminal nucleus. Treatment with both drugs did not affect tooth movement, but reduced c-fos expression in the caudalis subnucleus. No changes in c-fos expression were seen in the oralis and interpolaris subnuclei. We conclude that neither celecoxib nor acetaminophen seems to affect tooth movement, when used for 2 days, but both drugs are able to reduce the activation of brain structures related to nociception. Short-term treatment with celecoxib, thus, may be a therapeutic alternative to acetaminophen when the latter is contraindicated.
Assuntos
Acetaminofen/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Neurônios/efeitos dos fármacos , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Técnicas de Movimentação Dentária , Núcleo Espinal do Trigêmeo/efeitos dos fármacos , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Celecoxib , Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Incisivo , Masculino , Maxila/diagnóstico por imagem , Maxila/efeitos dos fármacos , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Radiografia , Ratos , Ratos Wistar , Núcleo Espinal do Trigêmeo/metabolismoRESUMO
Recent studies revealed that vasopressinergic neurons have a high content of cys-leukotriene C(4) (LTC(4)) synthase, a critical enzyme in cys-leukotriene synthesis that may play a role in regulating vasopressin secretion. This study investigates the role of this enzyme in arginine vasopressin (AVP) release during experimentally induced sepsis. Male Wistar rats received an i.c.v. injection of 3-[1-(p-chlorobenzyl)-5-(isopropyl)-3-tert-butylthioindol-2-yl]-2, 2-dimethylpropanoic acid (MK-886) (1.0 microg/kg), a leukotrienes (LTs) synthesis inhibitor, or vehicle, 1 h before cecal ligation and puncture (CLP) or sham operation. In one group of animals the survival rate was monitored for 3 days. In another group, the animals were decapitated at 0, 4, 6, 18 and 24 h after CLP or sham operation, and blood was collected for hematocrit, serum sodium and nitrate, plasma osmolality, protein and AVP determination. A third group was used for blood pressure measurements. The neurohypophysis was removed for quantification of AVP content, and the hypothalamus was dissected for LTC(4) synthase analysis by Western blot. Mortality after CLP was reduced by the central administration of MK-886. The increase in plasma AVP levels and hypothalamus LTC(4) synthase content in the initial phase of sepsis was blocked, whereas the decrease in neurohypophyseal AVP content was partially reversed. Also the blood pressure drop was abolished in this phase. The increase of serum nitric oxide and hematocrit was reduced, and the decrease in plasma protein and osmolality was not affected by the LTs blocker. In the final phase of sepsis, the plasma AVP level and the hypothalamic LTC(4) synthase content were at basal levels. The central administration of MK-886 increased the hypothalamic LTC(4) synthase content but did not alter the plasma and neurohypophysis AVP levels observed, or the blood pressure during this phase. These results suggest that the central LTs are involved in the vasopressin release observed during sepsis.
Assuntos
Arginina Vasopressina/metabolismo , Glutationa Transferase/antagonistas & inibidores , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Leucotrienos/biossíntese , Sepse/enzimologia , Animais , Arginina Vasopressina/sangue , Modelos Animais de Doenças , Glutationa Transferase/metabolismo , Hematócrito , Hipotensão/tratamento farmacológico , Hipotensão/enzimologia , Hipotensão/fisiopatologia , Indóis/farmacologia , Leucotrieno C4/biossíntese , Inibidores de Lipoxigenase/farmacologia , Masculino , Óxido Nítrico/sangue , Neuro-Hipófise/efeitos dos fármacos , Neuro-Hipófise/metabolismo , Ratos , Ratos Wistar , Sepse/fisiopatologiaRESUMO
A correlation between pain sensation and neuronal c-fos expression has been analyzed following experimental rapid maxillar expansion (RME). Adult male Wistar rats were anaesthetized and divided into three groups: animals that received an orthodontic apparatus, which was immediately removed after the insertion (control), animals that received an inactivated orthodontic apparatus (without force), and animals that received an orthodontic apparatus previously activated (140 g force). After 6, 24, 48, or 72 h, the animals were re-anaesthetized, and perfused with 4% paraformaldehyde. The brains were removed, fixed, and sections containing brain structures related to nociception were processed for Fos protein immunohistochemistry (IHC). The insertion of the orthodontic apparatus with 140 g was able to cause RME that could be seen by radiography. The IHC results showed that the number of activated neurons in the different nuclei changed according to the duration of appliance insertion and followed a temporal pattern similar to that of sensations described in clinics. The animals that received the orthodontic apparatus without force did not show RME but a smaller c-fos expression in the same brain structures. In conclusion, we demonstrate that orthodontic force used for palate disjunction activates brain structures that are related to nociception, and that this activation is related to the pain sensation described during orthodontic treatment.
Assuntos
Vias Aferentes/metabolismo , Encéfalo/metabolismo , Maxila/inervação , Neurônios Aferentes/metabolismo , Nociceptores/metabolismo , Dor/fisiopatologia , Vias Aferentes/anatomia & histologia , Animais , Biomarcadores/metabolismo , Encéfalo/anatomia & histologia , Mapeamento Encefálico , Imuno-Histoquímica , Masculino , Maxila/lesões , Maxila/cirurgia , Aparelhos Ortodônticos/efeitos adversos , Dor/etiologia , Dor/metabolismo , Substância Cinzenta Periaquedutal/anatomia & histologia , Substância Cinzenta Periaquedutal/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Núcleo Espinal do Trigêmeo/anatomia & histologia , Núcleo Espinal do Trigêmeo/metabolismoRESUMO
AIM: To evaluate ex vivo the efficacy of 35% hydrogen peroxide for intracoronal bleaching when activated by LEDs, halogen lamp or by the walking bleach technique. METHODOLOGY: Forty extracted human maxillary central incisors had their crowns resected 1 mm below the amelo-cemental junction and were submitted to artificial staining in centrifuged rat haemolysed blood. A 2-mm thick glass ionomer cervical plug was placed inside the canal, at the level of the amelo-cemental junction. Samples were divided randomly into five groups: group I received 35% hydrogen peroxide gel activated by LEDs. Group II received 35% hydrogen peroxide gel activated by a halogen lamp-based light curing unit. Group III received 35% hydrogen peroxide gel followed by the walking bleach technique. Group IV was neither artificially stained nor bleached (positive control) and group V was stained, but not bleached (negative control). The shade of the teeth was assessed visually by three independent and calibrated evaluators, before and after bleaching. The results were analysed using Kruskal-Wallis one-way analysis of variance and Dunn's post-test. RESULTS: No statistical differences regarding sample shades were found amongst groups for the tested internal bleaching techniques (P > 0.05). CONCLUSIONS: Hydrogen peroxide for intracoronal bleaching when activated either by LEDs, halogen lamp or by the walking bleach technique presented similar efficacy.
Assuntos
Clareamento Dental/métodos , Descoloração de Dente/tratamento farmacológico , Adulto , Idoso , Análise de Variância , Animais , Sangue , Halogênios , Humanos , Peróxido de Hidrogênio/uso terapêutico , Incisivo , Luz , Masculino , Pessoa de Meia-Idade , Oxidantes/uso terapêutico , Ratos , Semicondutores , Dente não VitalRESUMO
AIM: To evaluate the influence of mineral trioxide aggregate (MTA) on apexification and periapical healing of teeth in dogs with incomplete root formation and previously contaminated canals and to verify the necessity of employing calcium hydroxide paste before using MTA. METHODOLOGY: Twenty premolars from two 6-month old dogs were used. After access to the root canals and complete removal of the pulp, the canal systems remained exposed to the oral environment for 2 weeks. Canal preparation was then carried out using Hedström files, under irrigation with 1% sodium hypochlorite, 1 mm short of the radiographic apex. After drying, the canals of two premolars in each dog were left empty (control group). The other eight teeth in each animal were divided into two experimental groups. The apical thirds of the canals of group 1 were filled with MTA. In the teeth of group 2, the canals were dressed with a calcium hydroxide-propylene glycol paste. After 1 week, the paste was removed and the apical third was filled with MTA. All teeth were restored with reinforced zinc oxide cement (IRM) and amalgam. The animals were killed 5 months later, and blocks of the teeth and surrounding tissues were submitted to histological processing. The sections were studied to evaluate seven parameters: formation of an apical calcified tissue barrier, level of barrier formation, inflammatory reaction, bone and root resorption, MTA extrusion, and microorganisms. Results of experimental groups were analysed by Wilcoxon's nonparametric tests and by the test of proportions. The critical value of statistical significance was 5%. RESULTS: Significant differences (P < 0.05) were found in relation to the position of barrier formation and MTA extrusion. The barrier was formed in the interior of the canal in 69.2% of roots from MTA group only. In group 2, it was formed beyond the limits of the canal walls in 75% of the roots. MTA extrusion occurred mainly in roots from group 2. There was similarity between the groups for the other parameters. CONCLUSIONS: Mineral trioxide aggregate used after root canal preparation favoured the occurrence of the apexification and periapical healing. The initial use of calcium hydroxide paste was not necessary for apexification to occur, and has shown to be strongly related to the extrusion of MTA and formation of barriers beyond the limits of the root canal walls.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Tratamento do Canal Radicular/métodos , Silicatos/farmacologia , Ápice Dentário/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Hidróxido de Cálcio/farmacologia , Cães , Combinação de Medicamentos , Radiografia , Preparo de Canal Radicular/métodos , Ápice Dentário/diagnóstico por imagem , Doenças Dentárias/diagnóstico por imagem , Doenças Dentárias/tratamento farmacológicoRESUMO
AIM: To evaluate ex vivo the capacity of the Tri Auto ZX to locate the apical foramen during root canal retreatment. METHODOLOGY: The root canals of 62 maxillary and mandibular canines were prepared to a length 1 mm short of the apical foramen, to an apical size 35 using 1% sodium hypochlorite as an irrigant. Once prepared, the length of each tooth was measured directly using a size 15 K-Flexofile introduced in the canal until the tip was visible at the apical foramen. After the file was removed, its length was recorded to a precision of 0.01 mm using a calliper. These direct lengths (DL) became the 'gold standard' for comparison with the electronic lengths (EL) derived from the Tri Auto ZX. After direct measurement, the tooth was measured electronically (EL1) and the canals were filled using lateral condensation of gutta-percha cones and sealer. Seven days later the root filling was removed using solvent, Gates-Glidden burs, and K-files, and new electronic lengths determined (EL2). The electronic lengths (EL1 and EL2) were compared with the DL, and the differences were analysed statistically using the proportions test and Student's t-test. RESULTS: At a tolerance limit of +/-0.5 mm, EL1 coincided with the DL in 76% of cases. Lengths obtained in the presence of remnant of filling material (EL2) coincided in 81% of cases. The proportions test used to compare these percentages showed no statistically significant difference between EL1 and EL2 (P > 0.05). The Student's t-test revealed a statistically significant difference (P < 0.05) between the means of the differences between DL/EL1 (-0.36 mm) and DL/EL2 (-0.04 mm). CONCLUSION: The Tri Auto ZX was accurate to +/-0.5 mm in more than 80% of teeth following removal of root fillings.
Assuntos
Instrumentos Odontológicos , Cavidade Pulpar/anatomia & histologia , Odontometria/instrumentação , Ápice Dentário/anatomia & histologia , Dente Canino/anatomia & histologia , Eletrônica Médica , Humanos , Reprodutibilidade dos Testes , Retratamento , Preparo de Canal Radicular/instrumentaçãoRESUMO
In the rat experimental model, molar tooth movement induced by Waldo's method is known to cause a temporally and spatially defined pattern of brain neuronal activation. Since orthodontic correction usually involves the entire dental arch, we used a spring-activated appliance to extend the investigation to incisors, and we included brain regions related to antinociception. Adjustment of the non-activated appliance on incisors resulted in c-fos expression in the dorsal raphe, peri-aqueductal gray matter, and the locus coeruleus, in addition to trigeminal sensory subnuclei and the parabrachial nucleus, where neuronal activation has already been detected in previous studies on molar tooth movement. Appliance activation with a 70-g force resulted in a further increase in Fos-immunoreactive neurons in the trigeminal sensory subnucleus caudalis and in the dorsal raphe. This result suggests that there is a recruitment of neurons related to nociception and to antinociception when tooth movement is increased.
Assuntos
Encéfalo/metabolismo , Genes fos/genética , Incisivo/patologia , Proteínas Proto-Oncogênicas c-fos/análise , Técnicas de Movimentação Dentária , Analgésicos/farmacologia , Animais , Encéfalo/patologia , Genes fos/efeitos dos fármacos , Ketamina/farmacologia , Locus Cerúleo/metabolismo , Locus Cerúleo/patologia , Masculino , Modelos Animais , Neurônios/metabolismo , Neurônios/ultraestrutura , Nociceptores/metabolismo , Nociceptores/ultraestrutura , Aparelhos Ortodônticos , Dor/genética , Substância Cinzenta Periaquedutal/metabolismo , Substância Cinzenta Periaquedutal/patologia , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Ratos , Ratos Wistar , Recrutamento Neurofisiológico/genética , Formação Reticular/metabolismo , Formação Reticular/patologia , Técnicas de Movimentação Dentária/instrumentação , Núcleos do Trigêmeo/metabolismo , Núcleos do Trigêmeo/patologia , Xilazina/farmacologiaRESUMO
This paper describes a case in which pulp therapy was provided in a fused maxillary primary central incisor in a 4-year-old patient with a history of fistula on the gingival mucosa. The tooth involved was larger than expected, suggesting fusion. The diagnosis of fusion was confirmed on radiographical examination. The clinical management of the case is described and the diagnosis and treatment discussed.
Assuntos
Dentes Fusionados/complicações , Incisivo/anormalidades , Tratamento do Canal Radicular , Dente Decíduo/anormalidades , Pré-Escolar , Fístula Dentária/etiologia , Doenças da Polpa Dentária/complicações , Doenças da Polpa Dentária/terapia , Feminino , HumanosRESUMO
Our study corroborated previous findings on the distribution of ANP and co-localization of ANP and OT in hypothalamic magnocellular neurons. We detected ANP/OT in smaller cells which apparently corresponded to parvocellular neurons and additionally a massive group of ANP immunoreactive fibers from periventricular regions to the median eminence, here closely associated with oxytocinergic fibers originated from PVN. ANP immunoneutralization did not change the basal OT level but blocked the OT secretion normally induced by osmotic stimulus. Thus, endogenous hypothalamic ANP seems necessary to stimulate OT release in the hyperosmolality condition.
Assuntos
Fator Natriurético Atrial/fisiologia , Hipotálamo/fisiologia , Ocitocina/metabolismo , Animais , Anticorpos Bloqueadores/administração & dosagem , Anticorpos Bloqueadores/farmacologia , Fator Natriurético Atrial/antagonistas & inibidores , Hipotálamo/citologia , Hipotálamo/metabolismo , Imuno-Histoquímica , Injeções Intraventriculares , Masculino , Eminência Mediana/metabolismo , Neurônios/metabolismo , Ratos , Ratos WistarRESUMO
The goal of this study was to determine factors related to the occurrence of dental trauma in permanent teeth of children assisted at the Pediatric Dentistry Clinic of the Federal University of Santa Catarina (UFSC) Florianópolis, Brazil. During a period of 18 months, 36 children between 7 and 12 years of age had 72 traumatized teeth treated. The children were all assisted by one professional, a dentist working as a trainee of the Pediatric Dentistry Clinic. The occurrence of trauma was higher in male patients (61.3%) and in children between 8 and 9 years old with an average age of mean=9.4 years. In the group assisted, 63.9% of the children had more than one traumatized tooth and trauma reoccurred 19.4% of the time. The maxillary anterior teeth represented 96.1% of the cases and the central incisor teeth were the most affected. Both sides of the mouth had approximately the same number of traumas. Fractures were more frequent (51.4%) than luxations (48.6%). Enamel/dentin crown fractures represented 51.4% of the total traumatized teeth. Falls were the main cause of trauma (83.3%). A dental professional assisted 36.1% of the children in some way during the first 24 h after the incident. The study concluded that the permanent dentition is mostly affected by crown fractures that occur especially on maxillary central incisor teeth in patients between 8 and 9 years of age. The major etiological factor is falls that affected more than one tooth. Re-occurrence of trauma is fairly common.
Assuntos
Traumatismos Dentários/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Fatores Etários , Brasil/epidemiologia , Criança , Esmalte Dentário/lesões , Dentina/lesões , Feminino , Humanos , Incidência , Incisivo/lesões , Masculino , Maxila , Recidiva , Fatores Sexuais , Avulsão Dentária/epidemiologia , Coroa do Dente/lesões , Fraturas dos Dentes/epidemiologia , Raiz Dentária/lesõesRESUMO
A four-year-old child was presented to the Pediatric Dentistry Clinic of the Federal University, 21 days after an incident in which canine first and second primary molar teeth were avulsed, due to a trauma to the face. This was confirmed on radiological examination. The clinical examinations showed that tissues were normal. A removable space-maintaining dental-mucosa supported appliance was made in acrylic resin to replace the three missing teeth. After a period of eight months, the tissues were preserved, the device is helping the child to eat, to speak, and preserving the appearance of the patient. Radiograph examinations have shown that the first molar tooth and canine, first pre molar and second pre molar teeth are erupting normally. Trauma in primary dentition can cause psychological, morphological and functional problems. In the presented case the treatment was planned to recuperate the function and to avoid problems from the premature loss of primary teeth.
Assuntos
Dente Canino/lesões , Dente Molar/lesões , Aparelhos Ortodônticos Removíveis , Mantenedor de Espaço em Ortodontia/instrumentação , Avulsão Dentária/terapia , Dente Decíduo/lesões , Resinas Acrílicas , Dente Pré-Molar/diagnóstico por imagem , Pré-Escolar , Dente Canino/diagnóstico por imagem , Estética Dentária , Traumatismos Faciais/complicações , Seguimentos , Humanos , Masculino , Mastigação/fisiologia , Dente Molar/diagnóstico por imagem , Desenho de Aparelho Ortodôntico , Radiografia Interproximal , Radiografia Panorâmica , Fala/fisiologia , Erupção Dentária/fisiologiaRESUMO
Extracellular volume expansion (EVE) was performed in intact rats and 24 h after locus coeruleus (LC) lesions or sham-operation. Blood pressure was registered 5 min before and after EVE. At the end of the experiment the animals were decapitated and blood was collected from the trunk for quantification of plasma atrial natriuretic peptide (ANP). All experimental groups showed similar basal blood pressure. Volume expansion caused a slight decrease in blood pressure and an increase in ANP secretion in all groups, but these changes were significantly enhanced in animals bearing a lesion in the anterior region of the LC. There was no pronounced c-fos expression in any region of the LC 2 h after EVE in intact animals. In conclusion, the data support the idea that the LC does not participate in blood pressure control in resting conditions. However, the anterior region of the LC seems to play a role when adjustments of blood pressure and excretion of water and sodium are necessary during changes in blood volume. The results on c-fos expression are in accordance with the idea that this nucleus may be part of an inhibitory pathway which modulates the circuits of control for depressor reflex response and ANP secretion after extracellular volume expansion.