RESUMEN
PURPOSE: To evaluate the possible geno/cytotoxic effects of dental composite materials by assessing the frequency of micronuclei formation and other nuclear abnormalities in the exfoliated buccal epithelium. METHODS: Swabs were taken from the buccal mucosa of 85 young healthy subjects. All participants had healthy dentition or dentition restored only with composite materials. Genotoxicity and cytotoxicity was assessed by micronucleus assay. RESULTS: The results indicated no significant difference in number of oral mucosa cells with micronuclei in subjects with different numbers of composite restored tooth surfaces (P= 0.476). Also, the number of restored surfaces had no effect on nuclear alterations closely related to cytotoxicity, such as karyolysis (P= 0.572), karyorrehexis (P= 0.573) and picnosis (P= 0.765). CLINICAL SIGNIFICANCE: Despite doubts about the safe clinical use of resin composites, this study found no evidence that composite materials trigger long-term cytogenetic damage in the epithelial cells of buccal mucosa in humans. There is no objective and quantifiable evidence of genotoxicity induced by composite restorative materials in clinical practice.
Asunto(s)
Resinas Compuestas/toxicidad , Materiales Dentales/toxicidad , Células Epiteliales/efectos de los fármacos , Mucosa Bucal/citología , Pruebas de Mutagenicidad , Adulto , Femenino , Humanos , Masculino , Pruebas de MicronúcleosRESUMEN
Adult mesenchymal progenitor cells have enormous potential for use in regenerative medicine. However, the true identity of the progenitors in vivo and their progeny has not been precisely defined. We hypothesize that cells expressing a smooth muscle α-actin promoter (αSMA)-directed Cre transgene represent mesenchymal progenitors of adult bone tissue. By combining complementary colors in combination with transgenes activating at mature stages of the lineage, we characterized the phenotype and confirmed the ability of isolated αSMA(+) cells to progress from a progenitor to fully mature state. In vivo lineage tracing experiments using a new bone formation model confirmed the osteogenic phenotype of αSMA(+) cells. In vitro analysis of the in vivo-labeled SMA9(+) cells supported their differentiation potential into mesenchymal lineages. Using a fracture-healing model, αSMA9(+) cells served as a pool of fibrocartilage and skeletal progenitors. Confirmation of the transition of αSMA9(+) progenitor cells to mature osteoblasts during fracture healing was assessed by activation of bone-specific Col2.3emd transgene. Our findings provide a novel in vivo identification of defined population of mesenchymal progenitor cells with active role in bone remodeling and regeneration.
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Linaje de la Célula , Células Madre Mesenquimatosas/metabolismo , Actinas/genética , Actinas/metabolismo , Animales , Antígenos de Diferenciación/metabolismo , Células de la Médula Ósea/metabolismo , Regeneración Ósea , Remodelación Ósea , Diferenciación Celular , Femenino , Curación de Fractura , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Masculino , Ratones , Ratones Transgénicos , Fenotipo , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Tibia/patologíaRESUMEN
OBJECTIVE: To evaluate the efficacy and safety of an intraoral electrostimulation device, consisting of stimulating electrodes, an electronic circuit, and a power source, in treating xerostomia. The device delivers electrostimulation through the oral mucosa to the lingual nerve in order to enhance the salivary reflex. METHODS: The device was tested on a sample of patients with xerostomia due to Sjögren's syndrome and other sicca conditions in a 2-stage prospective, randomized, multicenter trial. Stage I was a double-blind, crossover stage designed to compare the effects of the electrically active device with the sham device, each used for 1 month, and stage II was a 3-month open-label stage designed to assess the long-term effects of the active device. Improvement in xerostomia severity from baseline was the primary outcome measure. RESULTS: A total of 114 patients were randomized. In stage I, the active device performed better than the sham device for patient-reported xerostomia severity (P<0.002), xerostomia frequency (P<0.05), quality of life impairment (P<0.01), and swallowing difficulty (P<0.02). At the end of stage II, statistically significant improvements were verified for patient-reported xerostomia severity (P<0.0001), xerostomia frequency (P<0.0001), oral discomfort (P<0.001), speech difficulty (P<0.02), sleeping difficulty (P<0.001), and resting salivary flow rate (P<0.01). CONCLUSION: Our findings indicate that daily use of the device alleviated oral dryness, discomfort, and some complications of xerostomia, such as speech and sleeping difficulties, and increased salivary output. The results show a cumulative positive effect of the device over the period of the study, from baseline to the end of the trial.
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Terapia por Estimulación Eléctrica/efectos adversos , Terapia por Estimulación Eléctrica/instrumentación , Síndrome de Sjögren/terapia , Xerostomía/terapia , Adulto , Anciano , Método Doble Ciego , Terapia por Estimulación Eléctrica/métodos , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Mucosa Bucal , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Síndrome de Sjögren/complicaciones , Resultado del Tratamiento , Xerostomía/etiologíaRESUMEN
The aims were to obtain epidemiological and etiological data on xerostomia in cross section of Croatian population, and to evaluate adherence to "American European Consensus Group" (AECG) classification criteria for Sjögren's syndrome (SSj), in order to identify possible need for improvements in differential diagnosis of xerostomia. A retrospective study among patients seen at the Department of oral medicine for complaints of dry mouth was performed. Three hundred and ninety-five patients met inclusion criteria. A data base was formed, comprising epidemiological, clinical and sialometric data, immunological, scintigraphic, ultrasonographic and histopathological findings of salivary glands, coupled with drug intake listings. Descriptive statistics were used for data analysis. Objective salivary hypofunction was found in 74% of our patients. The most common probable cause of xerostomia was side effect of pharmacotherapy. SSj was diagnosed in 6.7% of patients with xerostomia, whereas in another 8% of patients Sjögren's syndrome was strongly suspected, but labial gland biopsy wasn't performed, indicating a lack of adherence to AECG criteria for SSj diagnosis. Application of AECG criteria in differential diagnosis of patients with dry mouth is mandatory, as well as educating general practitioners, dentists and patients on xerogenic side effects of pharmacotherapy.
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Síndrome de Sjögren/clasificación , Síndrome de Sjögren/diagnóstico , Xerostomía/etiología , Diagnóstico Diferencial , Adhesión a Directriz , Humanos , Síndrome de Sjögren/complicacionesRESUMEN
The aim of the study was to assess the influence of fixed orthodontic appliance on Streptococcus (S.) mutans and S. sobrinus counts in orthodontic patients with regard to their previous caries experience (Decayed, Missing and Filled Teeth (DMFT) index) during the first 12 weeks of orthodontic treatment. Twenty-two patients that satisfied inclusion criteria (healthy systemic and periodontal condition, avoidance of antibiotic therapy and antiseptic mouthwashes in the past three months) were included. All clinical measurements took place prior to and 12 weeks after fixed orthodontic appliance placement, in the following order: 1) stimulated saliva flow (SS); 2) Simplified Oral Hygiene Index (OHI-S); and 3) DMFT. The method of polymerase chain reaction (PCR) was used to detect the presence of S. mutans and S. sobrinus at T1 and T2. T-test showed significant increase in DMFT index and SS between T1 and T2. Results also indicated significant improvement in OHI-S index. By use of the PCR method, S. mutans was detected in two patients at T1. At T2, two more patients had S. mutans, but the increase was not statistically significant. Using the same method, S. sobrinus was detected only in two patients at T2. In conclusion, fixed orthodontic appliances did not induce statistically significant changes in caries microflora even in the presence of enhanced oral hygiene habits.
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Salud Bucal , Soportes Ortodóncicos/microbiología , Saliva/microbiología , Streptococcus mutans/aislamiento & purificación , Streptococcus sobrinus/aislamiento & purificación , Adolescente , Adulto , Recuento de Colonia Microbiana , Índice CPO , Caries Dental/microbiología , Femenino , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Infecciones Estreptocócicas/diagnósticoRESUMEN
OBJECTIVE: To determine the difference in the levels of Streptococcus mutans and S sobrinus in stimulated saliva in orthodontic patients with different bracket types (stainless steel and esthetic brackets) using polymerase chain reaction and cultivation method. MATERIALS AND METHODS: Thirty-two patients, aged 13 to 30 years, were selected following these criteria: 1) orthodontic treatment indication, 2) systemic health, and 3) no tobacco and antibiotic consummation for three months prior to the commencement of the study. Patients were divided into two groups according to the bracket type; 16 patients formed the conventional bracket group (stainless steel brackets), and 16 patients formed the esthetic bracket group (plastic brackets). The levels of S mutans and S sobrinus in stimulated whole saliva samples were collected prior to fixed orthodontic appliance placement (T1) and 12 weeks after placement (T2), as were the Decayed, Missing, and Filled Surface Index (DMFS) and Oral Hygiene Index-Simplified (OHI-S). Mann-Whitney, Wilcoxon, and chi-square tests were used for statistical analysis. RESULTS: Statistical analysis (chi-square test) showed no difference in S mutans and S sobrinus counts among patients with different brackets at either T1 or T2. There was no difference in total bacteria counts after fixed orthodontic appliance placement. CONCLUSION: The number of colony-forming units of S mutans and S sobrinus in stimulated saliva samples does not seem to be significantly different between patients with stainless steel brackets and patients with plastic brackets.
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Soportes Ortodóncicos/microbiología , Saliva/microbiología , Streptococcus mutans/aislamiento & purificación , Streptococcus sobrinus/aislamiento & purificación , Adolescente , Adulto , Células Cultivadas , Recuento de Colonia Microbiana , Femenino , Humanos , Masculino , Diseño de Aparato Ortodóncico , Reacción en Cadena de la PolimerasaRESUMEN
Presently there is no clear evidence for the ability of mature osteogenic lineage cells to dedifferentiate. In order to identify and trace mature osteogenic lineage cells, we have utilized transgenic mouse models in which the dentin matrix protein 1 (Dmp1) promoter drives expression of GFP (active marker) or Cre recombinase (historic label) in preosteocytes/osteocytes. In long bone chip outgrowth cultures, in which cells on the bone surface were enzymatically removed, cells with previous activity of the Dmp1 promoter migrated onto plastic and down-regulated Dmp1-GFP expression. Dmp1Cre-labeled cells from these cultures had the potential to re-differentiate into the osteogenic lineage, while the negative population showed evidence of adipogenesis. We observed numerous Dmp1Cre-labeled osteoblasts on the surface of bone chips following their in vivo transplantation. Our data indicate that cells embedded in bone matrix are motile, and once given access to the extra bony milieu will migrate out of their lacunae. This population of cells is phenotypically and functionally heterogeneous in vitro. Once the preosteocytes/osteocytes leave lacunae, they can dedifferentiate, potentially providing an additional source of functional osteoblasts.
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Desdiferenciación Celular , Osteoblastos/citología , Osteocitos/citología , Animales , Proteínas de la Matriz Extracelular/genética , Fémur/citología , Genes Reporteros/genética , Ratones , Osteocitos/metabolismo , FenotipoRESUMEN
OBJECTIVE: To determine the effect of different bracket designs (conventional brackets and self-ligating brackets) on periodontal clinical parameters and periodontal pathogens in subgingival plaque. MATERIAL AND METHODS: The following inclusion criteria were used: requirement of orthodontic treatment plan starting with alignment and leveling, good general health, healthy periodontium, no antibiotic therapy in the previous 6 months before the beginning of the study, and no smoking. The study sample totaled 38 patients (13 male, 25 female; mean age, 14.6 ± 2.0 years). Patients were divided into two groups with random distribution of brackets. Recording of clinical parameters was done before the placement of the orthodontic appliance (T0) and at 6 weeks (T1), 12 weeks (T2), and 18 weeks (T3) after full bonding of orthodontic appliances. Periodontal pathogens of subgingival microflora were detected at T3 using a commercially available polymerase chain reaction test (micro-Dent test) that contains probes for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola. RESULTS: There was a statistically significant higher prevalence of A actinomycetemcomitans in patients with conventional brackets than in patients with self-ligating brackets, but there was no statistically significant difference for other putative periodontal pathogens. The two different types of brackets did not show statistically significant differences in periodontal clinical parameters. CONCLUSION: Bracket design does not seem to have a strong influence on periodontal clinical parameters and periodontal pathogens in subgingival plaque. The correlation between some periodontal pathogens and clinical periodontal parameters was weak.
Asunto(s)
Aggregatibacter actinomycetemcomitans/aislamiento & purificación , Placa Dental/microbiología , Encía/microbiología , Soportes Ortodóncicos/microbiología , Adolescente , Análisis de Varianza , Femenino , Humanos , Masculino , Diseño de Aparato Ortodóncico , Reacción en Cadena de la PolimerasaRESUMEN
OBJECTIVE: A previous sham-controlled multinational study demonstrated the short-term efficacy and safety for xerostomia treatment of an intraoral device that delivers electrostimulation to the lingual nerve. The objective of this study was to test the hypothesis that those beneficial effects would be sustained over an 11-month period. STUDY DESIGN: The device was tested on a mixed sample of 94 patients with xerostomia in an open-label, uncontrolled, prospective multicenter trial. Statutory outcome assessments were done at 5th, 8th, and 11th months and analyzed by multiple comparisons. RESULTS: Improvements achieved at month 5 from baseline were sustained throughout the follow-up period for the primary outcome, xerostomia severity, and the secondary outcomes resting whole salivary flow rate, xerostomia frequency, oral discomfort, and difficulties in speech, swallowing, and sleeping. No significant side effects were detected. CONCLUSIONS: The beneficial effects of a removable intraoral electrostimulating device were sustained for an 11-month period.