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The petals of the saffron crocus (Crocus sativus L.) are considered a waste material in saffron production, but may be a sustainable source of natural biologically active substances of nutraceutical interest. The aim of this work was to study the cardiovascular effects of kaempferol and crocin extracted from saffron petals. The antiarrhythmic, inotropic, and chronotropic effects of saffron petal extract (SPE), kaempferol, and crocin were evaluated through in vitro biological assays. The antioxidant activity of kaempferol and crocin was investigated through the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) assay using rat cardiomyoblast cell line H9c2. The MTT assay was applied to assess the effects of kaempferol and crocin on cell viability. SPE showed weak negative inotropic and chronotropic intrinsic activities but a significant intrinsic activity on smooth muscle with a potency on the ileum greater than on the aorta: EC50 = 0.66 mg/mL versus EC50 = 1.45 mg/mL. Kaempferol and crocin showed a selective negative inotropic activity. In addition, kaempferol decreased the contraction induced by KCl (80 mM) in guinea pig aortic and ileal strips, while crocin had no effect. Furthermore, following oxidative stress, both crocin and kaempferol decreased intracellular ROS formation and increased cell viability in a concentration-dependent manner. The results indicate that SPE, a by-product of saffron cultivation, may represent a good source of phytochemicals with a potential application in the prevention of cardiovascular diseases.
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Background: The use of medicated mouthwashes and gels in the home care maintenance of dental implants is controversial due to the possibility of residue deposition on the implant collar. The aim of this in vitro study was to analyse, by means of scanning electron microscopy (SEM), the amount of residues on dental implant collars treated with various commercial home dental care products. Methods: Gel and mouthwash products were tested on 10 implants. The gels included sodium fluoride, amine fluoride, and sodium hyaluronate products. The mouthwashes tested contained triclosan, nimesulide, stannous fluoride, amine fluoride, and hexetidine-chlorobutanol. The SEM observations were performed at different magnifications in double modality SE (secondary electrons) and BSE (backscattered electrons) to qualitatively assess any residual products. The image quantitative analysis was performed by Image J® software to assess areas occupied by residuals. All results were analysed by the same researcher with experience in electron microscopy. Results: The fluoride-based gel products left wider areas occupied by residuals than the mouthwash products. In particular the fluoride-based and hyaluronate products left the highest amount of residues. Among mouthwashes, fluoride-based and triclosan products showed the highest amount of residuals deposition. Discussion: Oral hygiene procedures and related professional products are fundamental to the prevention, treatment, and control of microorganisms. In the case of implants, mechanical and chemical plaque control strategies are even more important since the potentially harmful biofilm covers abiotic titanium surfaces. In situ fixture maintenance is crucial for dental implant therapy success. Correct recommendation of home care products for bacterial control is fundamental to the health of implants and their surrounding tissues. Conclusions: Data from this experimental study showed that home care commercial products in gel formulation, especially those containing fluoride, leave more residuals on titanium smooth surfaces than mouthwash products. The longer permanence of the products may lead to a more effective plaque control than other products.
Contexte: L'utilisation de bains de bouche et de gels médicamentés lors des soins d'entretien à domicile des implants dentaires porte à controverse en raison de la possibilité de dépôts de résidus sur le collet de l'implant. La présente étude in vitro visait à analyser par microscopie électronique à balayage (MÉB) la quantité de résidus sur les collets d'implants dentaires traités in vitro avec divers produits commerciaux de soins dentaires à domicile. Méthodologie: Les produits de gels et de bains de bouche ont été testés sur 10 implants. Les gels comprenaient les produits de fluorure de sodium, de fluorure d'amine et de hyaluronate de sodium. Les bains de bouche évalués contenaient du triclosan, de la nimésulide, du fluorure d'étain et du hexétidine-chlorobutanol. Les observations par MÉB ont été effectuées à diverses amplifications en modalité double SE (électrons secondaires) et BSE (électrons rétrodiffusés) pour évaluer de manière qualitative tout produit résiduel. L'analyse quantitative de l'image a été effectuée à l'aide du logiciel Image J® pour évaluer les zones ayant des résidus. Tous les résultats ont été analysés par le même chercheur expérimenté dans le domaine de la microscopie électronique. Résultats: Les produits de gels à base de fluorure ont laissé des résidus sur de plus vastes zones que les produits de bains de bouche. En particulier, les produits à base de fluorure et le hyaluronate ont laissé la plus grande quantité de résidus. Parmi les bains de bouche, les produits à base de fluorure et de triclosan ont révélé la plus grande quantité de dépôts de résidus. Discussion: Les procédures d'hygiène buccodentaire et les produits professionnels qui y sont liés sont essentiels à la prévention, au traitement et au contrôle des microorganismes. En matière d'implants, les stratégies de contrôle mécanique et chimique de la plaque sont encore plus importantes puisque le biofilm potentiellement nocif couvre les surfaces abiotiques du titane. L'entretien in situ du montage est primordial au succès de la thérapie de l'implant dentaire. La bonne recommandation de produits de soins à domicile pour le contrôle des bactéries est essentielle à la santé des implants et des tissus environnants. Conclusions: Les données de cette étude expérimentale ont montré que les produits commerciaux de soins à domicile en formule de gels, surtout ceux contenant du fluorure, laissent une plus grande quantité de résidus sur les surfaces lisses du titane que les produits de bains de bouche. La permanence plus longue des produits peut mener à un contrôle plus efficace de la plaque que d'autres produits.
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Implantes Dentários , Placa Dentária , Humanos , Microscopia Eletrônica de Varredura , Antissépticos Bucais , Higiene BucalRESUMO
During aging, usually graying of the hair occurs as a result of oxidative stress. Driven by social acceptance and self-perception of the exterior appearance, both men and women rely on hair dyeing products, in order to mask the graying hair. At the same time, a frequent use of synthetic products and treatment can damage the hair shaft; for this reason, this study aimed to evaluate the morphological effect of the herbal dye derived from Lawsonia inermis (henna), on hair. Dyed hairs were evaluated by means of SEM. Subsequently, they were compared, qualitatively and quantitatively, with undyed hairs. Results showed a positive impact on the cuticula pattern and on the diameters of the examined samples, after henna application. Different results, about the degree and the type of morphological changes occurring on pigmented hairs, may depend on the phenotype and on the health condition of hair, before dye treatment.
Durante el envejecimiento, generalmente se produce el envejecimiento del cabello como resultado del estrés oxidativo. Motivados por la aceptación social y la autopercepción de la apariencia, tanto hombres como mujeres confían en productos para teñir el cabello para enmascarar las canas. Al mismo tiempo, el uso frecuente de productos y tratamientos sintéticos puede dañar el tallo del cabello. Por esta razón, este estudio tuvo como objetivo evaluar el efecto morfológico del tinte derivado de Lawsonia inermis (henna) en el cabello. Los cabellos teñidos se evaluaron mediante SEM. Posteriormente, se compararon, cualitativa y cuantitativamente, con cabellos sin teñir. Los resultados mostraron un impacto positivo en el patrón de la cutícula y en los diámetros de las muestras examinadas, después de la aplicación de henna. Los diferentes resultados, sobre el grado y el tipo de cambios morfológicos que ocurren en los cabellos pigmentados, pueden depender del fenotipo y del estado de salud del cabello, antes del tratamiento con tinte.
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Humanos , Microscopia Eletrônica de Varredura , Folículo Piloso/efeitos dos fármacos , Lawsonia (Planta) , Tinturas para Cabelo/farmacologia , Folículo Piloso/ultraestrutura , Cabelo/efeitos dos fármacos , Cabelo/ultraestruturaRESUMO
Inflammatory diseases affecting the soft and hard tissues surrounding an implant represent a new challenge in contemporary implant dentistry. Among several methods proposed for the decontamination of titanium surfaces, the administration of topical 14% doxycycline gel seems to be a reliable option. In the present study, we evaluated the microbial effect of 14% doxycycline gel applied on titanium surfaces and exposed to human salivary microbes in anaerobic conditions. We also examined the composition of the exposed surfaces to assess the safe use of periodontal gel on titanium surfaces. Six anatase and six type 5 alloy titanium surfaces were used and divided into two groups: The test group and the positive control group. Both were cultured with human salivary samples in anaerobic conditions. On the test groups, 240 mg of periodontal gel was applied. The microbial assessment was performed with a colony-forming unit (CFU) count and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) to identify the species. The surface integrity was assessed using scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDS). The results demonstrated the microbial efficacy of the 14% doxycycline periodontal gel and its safe use on titanium surfaces. However, the SEM observations revealed the permanence of the gel on the titanium surfaces due to the physical composition of the gel. This permanence needs to be further investigated in vivo and a final polishing protocol on the titanium surface is recommended.
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The present study involved a qualitative and quantitative evaluation of tongue dorsum biofilms sampled from halitosis patients and healthy volunteers. The aim of the study was to quantify the distribution of Streptococcus spp. and Fusobacterium nucleatum within the oral halitosis biofilm in order to highlight the role of these bacterial members in halitosis. Tongue plaque samples from four halitosis-diagnosed patients and four healthy volunteers were analyzed and compared. The visualization and quantification of the tongue dorsum biofilm was performed combining fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM). Eubacteria, Streptococcus spp. and Fusobacterium nucleatum were stained using specific fluorescent probes. For a comparison of the two tested biofilm groups the Wilcoxon rank-sum test was used. Morphological analysis by CLSM illustrated the distribution of the species which were tracked. Streptococcus spp. appeared to be enclosed within the samples and always associated to F. nucleatum. Furthermore, compared to the control group the biofilm within the halitosis group contained significantly higher proportions of F. nucleatum and Streptococcus spp., as revealed by the FISH and CLSM-analysis. The total microbial load and relative proportions of F. nucleatum and Streptococcus spp. can be considered as causative factors of halitosis and thus, as potential treatment targets.
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Biofilmes , Fusobacterium nucleatum , Halitose , Streptococcus , Língua , Fusobacterium nucleatum/fisiologia , Halitose/microbiologia , Humanos , Hibridização in Situ Fluorescente , Microscopia Confocal , Streptococcus/fisiologia , Língua/microbiologiaRESUMO
Objective To define the association between mandibular fractures and alterations of the cranio-atlo-axial joint (CAAJ). Methods 315 cases of displaced mandibular fractures were retrospectively evaluated by CT scan and cervical X-ray for associated alterations of the CAAJ. Statistical analysis employed the chi-square and Cohen's kappa coefficient. Results Single fractures amounted to 69.84% and multiple fractures to 30.16% of total fractures. CT scans showed a rotation of the atlas on the same side of single fractures and subluxation of the CAAJ. Vertical derangement of the joint was observed in 79.65% of single fractures and in 20.35% of multiple fractures. Approximately16.19% of all displaced mandibular fractures showed cervical disorders at long-term follow-up. Discussion The outcomes of this study revealed an association between traumatic mandibular fractures and CAAJ, accompanied by clinical disorders. These conditions require clinical attention due to their effects on long-term craniocervical functionality and future forensic issues.
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Atlas Cervical , Luxações Articulares , Fraturas Mandibulares , Vértebras Cervicais , Humanos , Estudos RetrospectivosRESUMO
Saffron extracts have a long history of application as skin protectant, possibly due to their ability to scavenge free radicals. In this work, the performance of a hydrogel enriched with antioxidant compounds isolated from saffron crocus (Crocus sativus L.) petals was tested. These hydrogels could be considered as new drug delivery system. Hydrogels are crosslinked polymer networks that absorb large quantities of water but retain the properties of a solid, thus making ideal dressings for sensitive skin. We tested antioxidant-enriched hydrogels on primary mouse fibroblasts. Hydrogels enriched with kaempferol and crocin extracted from saffron petals showed good biocompatibility with in vitro cultured fibroblasts. These new types of hydrogels may find applications in wound treatment and/or beautification.
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Antioxidantes/farmacologia , Crocus/química , Hidrogéis/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Antioxidantes/química , Carotenoides/química , Carotenoides/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos/efeitos dos fármacos , Flores/química , Hidrogéis/química , Quempferóis/farmacologia , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
Lingual mandibular foramina are peculiar anatomical variations often present on the bone surface of the inferior jaw. These structures host vascular and nervous anastomosis deriving from the branches of the submental artery, lingual artery, and the mylohyoid nerve. Reports pointed out intra-operative massive bleeding accidents during implant interventions occurred in this area. The aim of this systematic review and meta-analysis was to summarize quantitatively the features of the lingual foramina on the midline of the inferior jaw. We performed a systematic review and meta-analysis complying the PRISMA statement and registering it in PROSPERO database. The frequency rate of the foramina resulted to have a point estimate of 0.965. The means of the diameters showed to have a point estimate of 0.840 with a standard error of 0.06. The results showed a significant high frequency reported in the literature of this variation, with a quite important diameter, sign of significant caliber of the related vessels. Even if this variation is underreported in modern textbooks of oral anatomy, we suggest an accurate screening via CT scan pre-operatively. In addition, a proper risk management is necessary to minimize injure hazard and properly managing the vascular plexus of the anterior floor of oral cavity.
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Mandíbula/anatomia & histologia , Variação Anatômica , Humanos , Mandíbula/diagnóstico por imagem , Procedimentos Cirúrgicos BucaisRESUMO
Along with the emerging needs of the dental patients, numerous techniques for oral tissue stimulation and regeneration were developed to be employed in the modern implant rehabilitation therapies. The Concentrated Growth Factors (CGF) are a relatively new therapeutic presidium that can be used for this purpose, enhancing the regenerative potential property of blood cells. Although literature presents numerous studies evaluating the CGF for their clinical uses and efficacy, data regarding their biological characteristics are very few. The present study evaluates and describes the CGF structural morphology by means of classical histological methods, using haematoxilin-eosin and azan mallory stains. A three layers organization with a fibrin complex network was noted, with blood corpuscular elements entrapped, especially in the most external layer. These descriptions enrich the knowledge about this new type of membrane, showing the bio-morphological side of the regenerative techniques. These findings will be useful in clinical practice for the choice of the most suitable technique in each implant rehabilitation.
Junto con las nuevas necesidades dentales de los pacientes, se han desarrollado numerosas técnicas para la estimulación y regeneración de los tejidos orales para ser empleadas en las modernas terapias de rehabilitación de implante. Los Factores de Crecimiento Concentrados (FCC) son relativamente una nueva alternativa terapéutica que pueden utilizarse para este propósito, mejorando la propiedad regenerativa potencial de las células de la sangre. A pesar de que la literatura presenta numerosos estudios que evalúan los FCC por sus usos clínicos y su eficacia, los datos relativos a sus características biológicas son muy escasos. El presente estudio evalúa y describe la morfología estructural de los FCC por medio de métodos histológicos tradicionales, utilizando hematoxilina-eosina y tinción de Azan Mallory. Se observó una organización en tres capas con una compleja red de fibrina, con elementos corpusculares de la sangre atrapados, especialmente en la capa más externa. Estas descripciones enriquecen el conocimiento acerca de este nuevo tipo de membrana, que muestra el lado biomorfológico de las técnicas regenerativas. Estos resultados serán de utilidad en la práctica clínica para la elección de la técnica más adecuada en los casos de rehabilitación con implantes.
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Humanos , Implantação Dentária , Regeneração Tecidual Guiada , Peptídeos e Proteínas de Sinalização IntercelularRESUMO
OBJECTIVE: The aim of this study was to evaluate the beneficial effect of NeoHeal during laser-assisted oral surgery. BACKGROUND DATA: Laser-assisted surgery is a less invasive technique than conventional surgery using a blade; however, the heat produced by the laser can damage tissue proximal to the treated area. We hypothesized the hydrogel NeoHeal could be applied during oral surgery and have similar benefits as those already described for dermatological surgery. METHODS: In our randomized controlled trial, we first selected 30 patients who were to undergo laser surgical intervention using a diode laser. Both at the end of intervention and at follow-up, each patient filled out a questionnaire comprising two questions. The answers to the questions were statistically analyzed with regard to frequency of each response, and validated by the Wilcoxon test with a p value <0.05 being considered significant. RESULTS: The use of NeoHeal significantly reduced the pain experienced by patients both during the intervention and at the 7-day follow-up. NeoHeal clearly reduces surgery-related pain experienced by patients. CONCLUSIONS: The results show positive feedback from the patients, demonstrating how the hydrogel pads are necessary, useful, and effective as a cooling aid in laser-assisted dental surgery.
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Terapia a Laser/instrumentação , Lasers Semicondutores , Procedimentos Cirúrgicos Bucais/instrumentação , Adulto , Temperatura Baixa , Difusão de Inovações , Feminino , Humanos , Masculino , Inquéritos e Questionários , Resultado do TratamentoRESUMO
PURPOSE: The aim of the present in vitro study was to evaluate the leakage observed for 2 different microbial species at the level of the implant-abutment (I-A) interface, and the marginal fit and size of microgap at the I-A interface in 2 different implant connections. METHODS: Ten specimens of each group were tested. The inner parts of 5 implants per group were inoculated with 0.1 µL of a viable Enterococcus faecalis suspension and 5 implants per group with Aggregatibacter actinomycetemcomitans. All of the vials containing the control specimens were incubated at 37°C under aerobic condition for E. faecalis and 37°C in presence of 5% CO2 for A. actinomycetemcomitans. They were maintained for 14 days, and the possible penetration of bacterial suspension into the surrounding solution was determined by the observation of turbidity of the broth. The I-A interface was evaluated for size of microgap and measured under SEM. Five implants of each group were evaluated. The marginal fit between implant and abutment was measured at 8 random locations in each assembly, under different magnifications at the interface. RESULTS: No leakages through the I-A interface were demonstrated for either type of connection evaluated. The microgap values of all I-A interfaces ranged from 0.008 to 2.009 µm; the differences between the 2 systems were statistically significant. CONCLUSIONS: The present study demonstrated that a good marginal fit of implant components seemed to be able to prevent bacterial leakage.
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Implantes Dentários/microbiologia , Infiltração Dentária/microbiologia , Aggregatibacter actinomycetemcomitans , Enterococcus faecalis , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de SuperfícieRESUMO
In descriptions of surgical procedures in mandible, often there is no mention of an anatomical variance, the genial spinal foramina, where nerves and vessels go through. Aim of this study is to investigate frequency, shape, and dimensions of these foramina. 56 computed tomography dentascans were analyzed with an implant planning software. The considered parameters were frequency, number, position, diameters, and length of canals; the collected data were inserted in a spreadsheet and statistically analyzed; therefore, they were compared with those found in the literature. The measurements agree with the ones found in earlier studies, except for the length of the inferior spinal canals, which resulted lesser than that found in the literature. The frequency of the inferior spinal foramina, the data related to the inferior spinal foramina diameter (cross scan), and the measurements related to the superior spinal foramina diameter (axial scan) resulted to be major compared to those reported in literature. These obtained results are clinically interesting because an implant planning software has been employed, daily used by operators, and that permits in vivo investigations. Furthermore, due to the possibility of hemorrhagic accidents in this mandibular region, these data are particularly interesting for all of the operators who make interventions in this area.
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Aim of this study was to investigate the gross anatomy of the root of European anterior teeth. A review of the dental literature shows that in the past the root morphology was investigated from the inner pulp chamber for endodontic therapies. In order to be admitted to the study, the teeth had to be undamaged. Each tooth was identified by a serial number and gauged by a millimeter tape (for the root length), a goniometer (for the root angle), and a millimeter gauge (for the root diameter). Furthermore, a statistical elaboration of the data was performed to underline the shape variations of the surface around the different sides of the root. At the end of the analysis, 12 parameters for each single-root tooth were described. The study highlights significant differences (p<0.01) only in two teeth of the maxillary arch (central incisor and canine) and in one tooth of the mandibular arch (central incisor). In both cases, the observed differences may be due to the sinuosity of the cement-enamel line. The Tables for each measured parameter were obtained for all examined classes of teeth, but a comparison with literature data was possible only for the "root length" parameter. This study can be considered innovative for the absence, in the scientific literature, of a statistical analysis of all parameters with the exception of the "root length". Moreover, it gives a detailed updating of the data relative to the European population creating a useful tool as well for surgical interventions during periodontal therapy (for example in the choice of the right ultrasonic handpiece) as for new CAD/CAM assisted implant manufacturing techniques.
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Dente Canino/anatomia & histologia , Cavidade Pulpar/anatomia & histologia , Incisivo/anatomia & histologia , Raiz Dentária/anatomia & histologia , População Branca , Humanos , Mandíbula , MaxilaRESUMO
AIM: To evaluate the possible differences in morphology and immunohistochemical expression of CD3, transforming growth factor beta1 (TGF-beta1), Smad7, alpha-smooth muscle actin (alpha-Sma), and collagen types I-VII of small and large intestine in Smad3 null and wild-type mice. METHODS: Ten null and ten wild-type adult mice were sacrificed at 4 mo of age and the organs (esophagus, small and large bowel, ureters) were collected for histology (hematoxylin and eosin, Masson thrichrome, silver staining), morphometry and immunohistochemistry analysis. TGF-beta1 levels of intestinal tissue homogenates were assessed by ELISA. RESULTS: No macroscopic intestinal lesions were detected both in null and wild-type mice. Histological and morphometric evaluation revealed a significant reduction in muscle layer thickness of small and large intestine in null mice as compared to wild-type mice. Immunohistochemistry evaluation showed a significant increase of CD3+ T cell, TGF-beta1 and Smad7 staining in the small and large intestine mucosa of Smad3 null mice as compared to wild-type mice. Alpha-Sma and collagen I-VII staining of small and large intestine did not differ between the two groups of mice. TGF-beta1 levels of colonic tissue homogenates were significantly higher in null mice than in wild-type mice. In preliminary experiments a significant reduction of TNBS-induced intestinal fibrosis was observed in null mice as compared to wild-type mice. CONCLUSION: Smad3 null mice are a useful model to investigate the in vivo role of the TGF-beta/Smad signalling pathway in intestinal inflammation and fibrosis.
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Intestino Grosso/química , Intestino Grosso/patologia , Intestino Delgado/química , Intestino Delgado/patologia , Proteína Smad3/genética , Actinas/análise , Animais , Complexo CD3/análise , Colágeno/análise , DNA/análise , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Fibrose/patologia , Fibrose/fisiopatologia , Imunidade Inata/genética , Imunidade Inata/fisiologia , Imuno-Histoquímica , Mucosa Intestinal/química , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiologia , Intestino Grosso/fisiologia , Intestino Delgado/fisiologia , Masculino , Camundongos , Camundongos Knockout , Músculo Liso/química , Fenótipo , Reação em Cadeia da Polimerase , Transdução de Sinais/fisiologia , Proteína Smad3/fisiologia , Proteína Smad7/análise , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/fisiologia , Fator de Crescimento Transformador beta1RESUMO
Many different synthetic biomaterials have been recently proposed in the majority of the techniques for hernioplasty and pelvic floor surgery. Required qualities of an implantable prosthetic material have been well established in the past and today the biomaterials better performing to this purpose are the monofilamented Polypropylene (Marlex) and the multifilamented Polyestere (Mersilene). But, in spite of a wide surgical use of these two kinds of meshes, many failures of these implantations are reported leading to removal of the prosthetic implanted material. If some of these failures are due to errors in surgical technique, others seem to be due to inadequacy of the selected material, too much soft or too much stiff, or too much or too little incorporated into the host tissue. This experiment investigated the different behaviour of in vitro cultured Human Dermal Fibroblasts, seeded on specimens of both meshes and then observed by Light (LM) and Scanning Electron Microscopy (SEM). Around the multifilamented threads of Polyestere mesh, fibroblasts could grow very well, filling the holes and making a continous cell layer completely envelopping the mesh. At the same culture time, around the Polypropylene mesh only big groups of fibroblasts were evident at the thread interlacing points. Therefore, it could be concluded that both meshes stimulate good fibroblast attachment and proliferation but in a very different way and amount; it will be up to the surgeon to select the appropriate mesh according to the specific surgical purpose.