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1.
Clin Endocrinol (Oxf) ; 97(1): 142-149, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35484952

RESUMEN

OBJECTIVE: Combination antiretroviral treatment (cART) allows for longer survival for people living with HIV and hence long-term complications of both disease and treatment are common. Our purpose was to evaluate bone alterations in men living with HIV (MLWH) and receiving cART and to identify associated factors that can be corrected or mitigated. PATIENTS AND DESIGN: Thirty MLWH and 36 healthy controls (≥50 years) were studied for areal bone mineral density (aBMD) and body composition (dual-energy X-ray absorptiometry), volumetric bone mineral density (vBMD) and bone microstructure (high-resolution peripheral quantitative computed tomography [HR-pQCT]), serum calcium, phosphate, parathyroid hormone, 25(OH)D, testosterone (T), estradiol (E2 ), glucose, creatinine, and albumin levels. RESULTS: The proportion of patients classified as osteoporosis (according to the lowest aBMD T-score) was higher among MLWH as compared to controls (17.9% vs. 5.9%, p = .011). The MLWH showed significant alterations in cortical and trabecular bone on HR-pQCT, which were not associated with the duration of HIV infection or cART. These differences in vBMD and bone microstructure seen in HR-pQCT persisted in the nonosteoporotic MLWH as compared to nonosteoporotic control subjects. Body mass index (BMI) and fat mass were lower in MLWH and positively associated with total vBMD, cortical bone area, and thickness. E2 and E2 /T ratios were lower in MLWH than in controls and significantly correlated with several cortical and trabecular bone parameters. Multivariate regression analysis entering simultaneously age, BMI, and E2 defined that E2 is an independent influence on bone parameters evaluated by HR-pQCT. CONCLUSION: MLWH have alterations in bone volumetric density and microstructure when compared with controls, irrespective of aBMD, which are associated with lower E2 and BMI.


Asunto(s)
Enfermedades Óseas Metabólicas , Infecciones por VIH , Absorciometría de Fotón/métodos , Anciano , Densidad Ósea , Brasil , Estradiol , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Radio (Anatomía)
2.
Sensors (Basel) ; 20(21)2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33120948

RESUMEN

The use of monitoring sensors is increasingly present in the context of precision agriculture. Usually, these sensor nodes (SNs) alternate their states between periods of activation and hibernation to reduce battery usage. When employing unmanned aerial vehicles (UAVs) to collect data from SNs distributed over a large agricultural area, we must synchronize the UAV route with the activation period of each SN. In this article, we address the problem of optimizing the UAV path through all the SNs to reduce its flight time, while also maximizing the SNs' lifetime. Using the concept of timeslots for time base management combined with the idea of flight prohibition list, we propose an efficient algorithm for discovering and reconfiguring the activation time of the SNs. Experimental results were obtained through the development of our own simulator-UAV Simulator. These results demonstrate a considerable reduction in the distance traveled by the UAV and also in its flight time. In addition, the model provides a reduction in transmission time by SNs after reconfiguration, thus ensuring a longer lifetime for the SNs in the monitoring environment, as well as improving the freshness and continuity of the gathered data, which support the decision-making process.

3.
Clin Oral Implants Res ; 30(11): 1142-1154, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31529643

RESUMEN

OBJECTIVE: To evaluate the outcomes of excessively loaded implants. MATERIAL AND METHODS: In five dogs, all mandibular premolars were extracted. After 3 months, six implants (three SLA® and three SLActive®) were placed (S). After 4 weeks, implants were restored: one single crown with stable occlusal contacts (SC), one crown and a cantilever unit with excessive occlusal contacts (OL), and a non-loaded implant (NL). Bleeding-on-probing (BoP), attachment level (AL), mucosal margin (GM) were assessed. Resonance frequency analysis (RFA) was assessed weekly. Standardized X-rays were taken at S, 4 and 24 weeks. RESULTS: Similar findings were observed for SLA® and SLActive® implants regarding PlI, GI, GM, AL, and BL. No significant differences were detected between baseline and 24-weeks or between treatment modalities for all clinical parameters (p > .05). Six months after loading, RFA values were significantly greater than at implant placement. No significant differences between treatment modalities were found. Linear radiographic measurements yielded similar results between SLA® and SLActive® implants. SLA® OL implants yielded a statistically significant gain on peri-implant bone density over all other groups (p = .012). Radiographic results were confirmed by descriptive histology. Technically, loosened occlusal screws occurred in 13.3% (SC = 3.3%; OL = 10%), while abutment fractures totalized 23.3% (SC = 6.6%; OL = 16.6%). CONCLUSIONS: Excessive occlusal load applied to implants (SLA® or SLActive®) restored with cantilevers did not cause loss of osseointegration or significant changes in their clinical, radiographic, or histologic outcomes. Early excessive occlusal load on SLA® implants promoted a gain in peri-implant bone density. Excessively loaded implants showed more technical complications.


Asunto(s)
Implantes Dentales , Titanio , Animales , Diseño de Prótesis Dental , Perros , Oseointegración , Propiedades de Superficie
4.
Clin Oral Implants Res ; 27(5): 545-52, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26031414

RESUMEN

OBJECTIVE: The aim of this study was to describe and to compare some characteristics of the soft tissue healing process around teeth and implants after flap surgery. MATERIAL AND METHODS: Five adult beagle dogs had their third and fourth lower premolars extracted. After 3 months, four implants per dog were placed on the healed alveolar ridge and allowed to heal non-submerged during 3 months. After 3 months, four regions characterized by one implant and one adjacent tooth were identified in each dog. One region was randomly selected and soft tissue ressective flap surgery was performed at its buccal aspect. The remaining three regions were randomly treated in an identical manner, and the dogs were sacrificed to provide biopsies representing healing intervals of 1, 2, 4, and 12 weeks. The biopsies were prepared for histological and morphological analyses. RESULTS: Morphometric and histometric analyses have shown that the gingival tissues surrounding teeth were completely healed after a 4-week interval. However, it took from 4 to 12 weeks for the peri-implant mucosa to heal completely. CONCLUSION: The healing process around teeth and implants follows a similar sequence of events. Nevertheless, the complete process of healing and maturation of the peri-implant tissues takes longer than around teeth.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Cicatrización de Heridas , Proceso Alveolar/cirugía , Animales , Perros , Mandíbula/cirugía , Distribución Aleatoria
5.
An Acad Bras Cienc ; 86(3): 1207-20, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25119733

RESUMEN

In northeastern Brazil, the reduction of the natural forest cover to a series of small, isolated fragments has had negative consequences for the local avian fauna, in particular, a loss of the more specialized species, while the populations of some generalists have tended to increase. The present study focuses on the composition and trophic groups of a bird community on a farm in the northeastern Brazilian state of Alagoas. Monthly surveys were conducted between November 2008 and October 2009, based on mist-netting and systematic observations. Overall, 112 species were recorded, of which 76 were associated with the two forest fragments surveyed, while all the others were observed exclusively in the surrounding matrix of pasture and orchards. The bird community presented a predominance of insectivorous species, followed by omnivores. However, specialized trunk-creeping and understory insectivores accounted for only around 15% of the species in this feeding category. The reduced diversity of other guilds and species with more specialized diets, and the complete absence of sensitive species such as large parrots and raptors, reflects the severe fragmentation and degradation of the local forests, which has greatly reduced the availability of dietary resources and breeding sites.


Asunto(s)
Biodiversidad , Aves/clasificación , Animales , Brasil , Densidad de Población , Dinámica Poblacional
6.
J Oral Maxillofac Surg ; 69(11): 2771-6, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21798649

RESUMEN

PURPOSE: With the increasing number of surgical procedures for osseointegrated implant placement, there has also been an increase in the number of professionals performing this procedure. Surgeons undergo different types of training, and this may influence their surgical experience. The objective of this study was to evaluate the effect of surgical experience on the osseointegration of dental implants. MATERIALS AND METHODS: A retrospective study was conducted using clinical charts from 2002 through 2008, during which time 265 implants were performed in 110 patients by 2 professionals who completed a postgraduate program in implant dentistry in 2002. Cases were selected for degree of difficulty, avoiding those involving areas that required bone grafts for the placement of implants, with a regular platform (3.75) and a height ranging from 10 to 13 mm. The criteria for evaluating implant osseointegration included clinical and radiographic evidence observed for a minimum period of 1 year, in accordance with the success criteria proposed by Albrektsson et al:(1)1) individual, unattached implant is immobile when tested clinically; 2) radiograph does not demonstrate evidence of peri-implant radiolucency; 3) vertical bone loss is less than 0.2 mm annually after the first year postimplantation; and 4) individual implant performance is characterized by an absence of signs and symptoms such as pain, infections, neuropathies, paresthesia, or violation of the mandibular canal. Implantation was performed in 2 stages. To relate the osseointegration rate with professional experience, cases were arranged by increasing order of placement date and were then evaluated per year and region. They were then separated into 2 groups: first 50 implants performed and implants performed after the first 50. RESULTS: The osseointegration rate of implants performed was 92.5%, with rates of 87.6% for those placed in the maxilla and 95.6% for those in the mandible. For the first 50 implants, the osseointegration rate was 84.0%, whereas in the implants performed thereafter, the rate was 94.4%. CONCLUSION: Surgical experience acquired during and after a postgraduate program in implant dentistry appears to influence osseointegration of dental implants, with a higher osseointegration rate found in implants performed by more experienced professionals.


Asunto(s)
Competencia Clínica/normas , Implantación Dental Endoósea/normas , Implantes Dentales , Oseointegración/fisiología , Pérdida de Hueso Alveolar/clasificación , Implantación Dental/educación , Implantación Dental Endoósea/métodos , Implantación Dental Endoósea/estadística & datos numéricos , Implantes Dentales/normas , Implantes Dentales/estadística & datos numéricos , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Tejido Periapical/diagnóstico por imagen , Radiografía , Estudios Retrospectivos , Torque , Resultado del Tratamiento
7.
J Clin Periodontol ; 37(7): 675-84, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20528960

RESUMEN

OBJECTIVE: To systematically assess the factors influencing tooth loss during long-term periodontal maintenance (PM). METHODS: CENTRAL, MEDLINE and EMBASE were searched up to and including September 2009. Studies limited to patients with periodontitis who underwent periodontal therapy and followed a maintenance care programme for the at least 5 years were eligible for inclusion in this review. Studies were considered for inclusion if they reported data on tooth loss during PM. RESULTS: The search strategy identified 527 potentially eligible articles, of which 13 retrospective case series were included in this review. The risk of bias assessment evaluated by the Newcastle-Ottawa scale showed that eight studies were considered of medium methodological quality and five of low methodological quality. Of 41,404 teeth present after active periodontal treatment, 3919 were lost during PM. The percentages of tooth loss due to periodontal reasons and of patients who did not experience tooth loss varied from 1.5% to 9.8% and 36.0% to 88.5%. Studies' individual outcomes showed that different patient-related factors (i.e. age and smoking) and tooth-related factors (tooth type and location, and the initial tooth prognosis) were associated with tooth loss during PM. CONCLUSIONS: The considerable heterogeneity found among studies did not allow definitive conclusions. Age, smoking and initial tooth prognosis were found to be associated with tooth loss during PM. Overall, patients must be instructed to follow periodic PM and quit smoking (smokers). Prospective cohort studies are required to confirm the possible predictors of tooth loss due to periodontal reasons. The allocation of patients into subgroups according to the type of periodontitis and smoking frequency will allow more accurate evaluations.


Asunto(s)
Profilaxis Dental , Periodontitis/complicaciones , Periodontitis/terapia , Pérdida de Diente/etiología , Factores de Edad , Humanos , Pronóstico , Proyectos de Investigación , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos
8.
Int J Oral Maxillofac Implants ; 25(2): 374-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20369098

RESUMEN

PURPOSE: The purpose of this study was to evaluate the area and volume of bone available for grafting in a donor retromolar region using computed tomography (CT). MATERIALS AND METHODS: Ten patients previously scanned by multislice CT were selected for evaluation. Images from partially and completely dentate patients at least 18 years of age were included in the study; those from patients with impacted or erupted third molars or intrabony lesions in the study area were not included. Computer software with appropriate tools was used to handle the images. Two calibrated observers made measurements separately. Safety margins in relation to the lingual cortex, the base of mandible, and the alveolar canal were established in each cross-section of the CTs. Measurements were done by using cross-sectional views, and the results were calculated after three-dimensional reconstruction, providing area and volume data. RESULTS: The mean area of bone available for grafting was 8.12 cm2 (range, 0.00 to 13.60 cm2) and 8.32 cm2 (range, 0.00 to 14.30 cm2) for observers 1 and 2, respectively. Mean available bone volume for grafting was 0.79 cm3 (range, 0.00 to 1.50 cm3) for observer 1 and 0.85 cm3 (range, 0.00 to 1.60 cm3) for observer 2. Interobserver analysis showed substantial agreement. CONCLUSION: The retromolar region showed a wide variety of anatomic differences among patients. Three-dimensional multislice CT allows reproducible measurements of the area and volume of the retromolar region.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Trasplante Óseo/patología , Mandíbula/diagnóstico por imagen , Recolección de Tejidos y Órganos , Tomografía Computarizada por Rayos X/métodos , Proceso Alveolar/diagnóstico por imagen , Anatomía Transversal , Cefalometría/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Mandíbula/cirugía , Variaciones Dependientes del Observador , Tamaño de los Órganos , Proyectos Piloto , Programas Informáticos
9.
Cochrane Database Syst Rev ; (2): CD007161, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19370675

RESUMEN

BACKGROUND: Gingival recession is defined as the oral exposure of the root surface due to a displacement of the gingival margin apical to the cemento-enamel junction and it is regularly linked to the deterioration of dental aesthetics. Successful treatment of recession-type defects is based on the use of predictable periodontal plastic surgery (PPS) procedures. OBJECTIVES: To evaluate the effectiveness of different root coverage procedures in the treatment of recession-type defects. SEARCH STRATEGY: The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched up to October 2008. The main international periodontal journals were handsearched. There were no restrictions with regard to publication status or language of publication. SELECTION CRITERIA: Only randomised controlled clinical trials (RCTs) of at least 6 months' duration evaluating recession areas (Miller's Class I or II > 3 mm) and that were treated by means of PPS procedures were included. DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. MAIN RESULTS: Twenty-four RCTs provided data. Only one trial was considered to be at low risk of bias. The remaining trials were considered to be at high risk of bias. The results indicated a significant greater reduction in gingival recession and gain in keratinized tissue for subepithelial connective tissue grafts (SCTG) compared to guided tissue regeneration with resorbable membranes (GTR rm). A significant greater gain in the keratinized tissue was found for enamel matrix protein when compared to coronally advanced flap (0.40 mm) and for SCTG when compared to GTR rm plus bone substitutes. Limited data exist on aesthetic condition change related to patients' opinion and patients' preference for a specific procedure. AUTHORS' CONCLUSIONS: Subepithelial connective tissue grafts, coronally advanced flap alone or associated with other biomaterial and guided tissue regeneration may be used as root coverage procedures for the treatment of localised recession-type defects. In cases where both root coverage and gain in the keratinized tissue are expected, the use of subepithelial connective tissue grafts seems to be more adequate. Randomised controlled clinical trials are necessary to identify possible factors associated with the prognosis of each PPS procedure. The potential impact of bias on these outcomes is unclear.


Asunto(s)
Recesión Gingival/cirugía , Gingivoplastia/métodos , Proteínas del Esmalte Dental/uso terapéutico , Regeneración Tisular Guiada Periodontal/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Clin Oral Implants Res ; 20(5): 452-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19250243

RESUMEN

AIM: The aim of the present study was to assess the influence of the chemical characteristics and roughness of titanium surfaces on the viability, proliferation and differentiation of osteoblast-like cells cultured in a medium supplemented with recombinant human bone morphogenetic protein-7 (rhBMP-7). MATERIAL AND METHODS: Osteo-1 cells were grown on titanium disks presenting with the following surfaces: (1) machined, (2) coarse grit-blasted and acid-attacked (SLA) and (3) chemically modified SLA (SLAmod) in the absence or presence of 20 ng/ml rhBMP-7 in culture medium. The viability and number of osteo-1 cells were evaluated after 24 h. Analyses of total protein content (TP) and alkaline phosphatase (AP) activity at 7, 14 and 21 days, collagen content at 7 and 21 days and mineralized matrix formation at 21 days were performed. RESULTS: Cell viability (P=0.5516), cell number (P=0.3485), collagen content (P=0.1165) and mineralized matrix formation (P=0.5319) were not affected by the different surface configurations or by the addition of rhBMP-7 to the medium. Osteo-1 cells cultured on SLA surfaces showed a significant increase in TP at 21 days. The ALPase/TP ratio (P=0.00001) was affected by treatment and time. CONCLUSION: The results suggest that the addition of rhBMP-7 to the culture medium did not exert any effect on the viability, proliferation or differentiation of osteoblast-like cells grown on the different surfaces tested. All titanium surfaces analyzed allowed the complete expression of the osteoblast phenotype such as matrix mineralization by osteo-1 cells.


Asunto(s)
Materiales Biocompatibles/farmacología , Proteína Morfogenética Ósea 7/fisiología , Diferenciación Celular/fisiología , Osteoblastos/fisiología , Titanio/farmacología , Animales , Materiales Biocompatibles/química , Calcificación Fisiológica/efectos de los fármacos , Calcificación Fisiológica/fisiología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Humanos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Ratas , Ratas Wistar , Proteínas Recombinantes , Propiedades de Superficie , Titanio/química
11.
J Can Dent Assoc ; 75(3): 203a-203f, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19356319

RESUMEN

OBJECTIVES: The objectives of this systematic review were (1) to evaluate results obtained with different periodontal plastic surgery procedures in the treatment of multiple recession-type defects and (2) to assess differences in results from randomized controlled trials and other types of studies (i.e., controlled clinical trials and case series). MATERIALS AND METHODS: The MEDLINE, EMBASE and CENTRAL databases were searched up to June 2008 to identify randomized controlled trials, controlled clinical trials and case series with a follow-up period of at least 6 months for patients with multiple recession-type defects who were treated with periodontal plastic surgery. RESULTS: Of 632 articles initially retrieved, only 16 were deemed suitable for more detailed analysis. Of these, only 4 case series met the inclusion criteria. Mean recession and clinical attachment level decreased substantially from baseline to final examination, and probing depth also declined. Mean width of keratinized tissue increased. Mean root coverage ranged from 94% to 98% over the 4 studies, and complete root coverage was achieved for 68% to 90% of patients in the 3 trials for which this variable was reported. CONCLUSIONS: Analysis of the limited information available in the dental literature showed improvements in clinical parameters with all of the periodontal plastic surgery procedures. Randomized controlled trials are needed to identify the indications for each surgical technique and any prognostic factors.


Asunto(s)
Recesión Gingival/cirugía , Gingivoplastia/métodos , Ensayos Clínicos Controlados como Asunto , Humanos
12.
J Dent ; 36(9): 659-71, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18584934

RESUMEN

OBJECTIVES: The objective of this systematic review was to answer the following question: 'Can subepithelial connective tissue grafts (SCTG) be considered the gold standard procedure in the treatment of recession-type defects?' DATA AND SOURCE: An electronic search (MEDLIINE, EMBASE and CENTRAL) for randomized controlled clinical trials with at least 6 months' follow-up comparing SCTG with other procedures for the treatment of gingival recession was performed up to December 2007. STUDY SELECTION: To be eligible to this review patients had to present a diagnosis of gingival recession with the following characteristics: (a) recession areas selected for treatment classified as Miller [Miller Jr PD. A classification of marginal tissue recession. International Journal of Periodontics & Restorative Dentistry 1985;5:8-13.] Class I or Class II of at least 2mm; (b) recession areas containing teeth with no caries or restorations; and (c) at least 10 participants per group at final examination. From a total of 568 references, 23 studies were considered relevant. The results indicated a statistically significant greater reduction in gingival recession for SCTG, when compared to acellular dermal matrix grafts and guided tissue regeneration with resorbable membranes (GTR rm). For clinical attachment level changes, differences between all groups were not significant. For changes in the keratinized tissue (KT), the results showed a statistically significant gain in the width of KT for SCTG when compared to GTR rm. CONCLUSION: The results of this review show that subepithelial connective tissue grafts provided significant root coverage, clinical attachment and keratinized tissue gain. Overall comparisons allow us to consider it as the 'gold standard' procedure in the treatment of recession-type defects.


Asunto(s)
Tejido Conectivo/trasplante , Recesión Gingival/cirugía , Gingivoplastia/métodos , Colágeno/uso terapéutico , Regeneración Tisular Guiada Periodontal , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estándares de Referencia , Piel Artificial
13.
Am J Dent ; 21(5): 318-22, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19024258

RESUMEN

PURPOSE: To evaluate the qualitative and quantitative differences on dental plaque formation on two different roughness titanium implant surfaces, i.e. machined and titanium plasma sprayed, as well as the amount of plaque removal by regular toothbrushing after 72-hour plaque accumulation. METHODS: Eight systemically healthy subjects were recruited from the patient pool of a private dental practice. All patients underwent oral hygiene instruction and full mouth prophylaxis. Subsequently, maxillary casts from all patients were obtained and removable 0.7 mm-thick acetate stents without occlusal contact points were fabricated to support four titanium specimens of 4 x 2 x 2 mm divided into two groups (machined and plasma sprayed). Subjects were instructed to wear the stents for 72 hours, full time, removing them only during regular oral hygiene. Subsequently, the appliances were immediately repositioned and then the test side was brushed for 20 seconds. At the end of the 72-hour period, the stents were removed and prepared for microbiological analysis. RESULTS: Both machined and plasma sprayed brushed surfaces presented statistically significant fewer bacteria than non-brushed surfaces. Similarly, regarding surface roughness, machined surfaces presented a total number of bacteria significantly smaller than those presented by plasma sprayed surfaces (P < 0.05). Statistically, the non-brushed machined turned surfaces presented a greater amount of Streptoccocus sp. when compared to the brushed machined surfaces. It was concluded that rough surfaces accumulated more dental plaque than polished surfaces. Both brushed surfaces presented less plaque accumulation, however, implant brushing was more effective on machined surfaces.


Asunto(s)
Materiales Biocompatibles Revestidos , Placa Dental/microbiología , Placa Dental/prevención & control , Titanio , Cepillado Dental , Adulto , Recuento de Colonia Microbiana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Propiedades de Superficie , Adulto Joven
14.
J Int Acad Periodontol ; 8(4): 115-24, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17042167

RESUMEN

The aim of the present study was to determine whether bacterial contamination of expanded polytetrafluoroethylene (e-PTFE) membranes and the degree of membrane exposure could affect the clinical results of guided tissue regeneration (GTR). Seven patients (aged 42 to 58 years) presented with twenty intrabony defects that were treated by GTR + DFDBA (decalcified freeze-dried bone allograft). Gingival recession, probing depths, and clinical attachment levels were recorded before surgery and 10 months subsequently. Exposure of the membrane was recorded at the moment of removal. The membranes were analyzed in three distinct regions by scanning electron microscopy (SEM): collar, medial and apical regions. The presence of host cells adhering to the e-PTFE membrane was determined and bacterial contamination was quantified as per Simion et al. (1994). Statistical analysis did not show significant differences for bacterial contamination or for the presence of host cells on the membrane surface at different levels of exposure (up to 30%, from 31% to 60%, and from 61% to 75%). Results were considered statistically significant at p < 0.05, according to the Kruskal-Wallis rank sum test. Exposure of the membrane and bacterial contamination did not modify the levels recorded. Bacterial contamination had an adverse effect on bone defect filling.


Asunto(s)
Placa Dental/microbiología , Regeneración Tisular Guiada Periodontal/métodos , Enfermedades Periodontales/cirugía , Politetrafluoroetileno , Adulto , Trasplante Óseo/métodos , Distribución de Chi-Cuadrado , Femenino , Humanos , Masculino , Membranas Artificiales , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Estadísticas no Paramétricas
15.
Microsc Res Tech ; 76(6): 633-40, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23564359

RESUMEN

The aim of the present research was to analyze ultrastructural and immunohistochemical aspects of the alveolar repair after the extraction of molars of alendronate (ALN)-treated rats. Wistar rats received 2.5mg/kg body wt/day of ALN during 14 days previously and 7, 14 and 21 days after the extraction of the second mandibular molar. Specimens were fixed in 2% glutaraldehyde + 2.5% formaldehyde under microwave irradiation, decalcified in 4.13% EDTA and paraffin embedded for TRAP histochemistry and immunohistochemistry for OPN, BSP and endoglin, or embedded in Spurr epoxy resin for TEM analysis. Additional specimens had their soft tissues removed and were processed for scanning electron microscopy. The ALN group presented latent TRAP-positive osteoclasts and nonresorbed alveolar crests with bacterial infection. Mild bone necrosis signs were observed at all time points studied. Ultrastructurally, empty osteocyte lacunae were observed and bone trabeculae surface presented hyalinized aspect. A significant delay in alveolar repair occurred, as well as decreased angiogenesis. ALN treatment provoked mild signs of bone necrosis, despite the high dose employed. The present findings add new information about the ultrastructural aspect of the early repair of rats under ALN treatment and highlight for giving attention when oral surgeries are performed in patients using this drug.


Asunto(s)
Alendronato/administración & dosificación , Conservadores de la Densidad Ósea/administración & dosificación , Extracción Dental , Alveolo Dental/citología , Alveolo Dental/fisiología , Cicatrización de Heridas , Animales , Histocitoquímica , Inmunohistoquímica , Microscopía Electrónica de Rastreo , Ratas Wistar
16.
J Environ Pathol Toxicol Oncol ; 32(4): 329-41, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24579785

RESUMEN

This study investigated the protective effect of pecan nut (Carya illinoensis) shell aqueous extract (AE) on the oxidative and morphological status of rat testis treated with cyclophosphamide (CP). Wistar rats received water or AE (5%) ad libitum for 37 days. On day 30, half of each group received a single intraperitoneal administration of vehicle or CP 200 mg/kg. After 7 days, the animals were killed and their testis removed. Rats treated with CP presented reduced levels of lactate dehydrogenase, vitamin C, and gluthatione, as well as decreased catalase activity, increased lipid peroxidation levels and superoxide dismutase activity, no alteration in carbonyl protein levels, and a loss of morphological testicular integrity. In contrast, cotreatment with pecan shell AE totally prevented the decrease of lactate dehydrogenase and vitamin C levels and catalase activity and partially prevented the depletion of gluthatione levels. Moreover, it totally prevented the increase in superoxide dismutase activity and lipid peroxidation levels and maintained testicular integrity. These findings show the protective role of pecan shell AE in CP-induced testicular toxicity. The use of this phytotherapy may be considered to minimize deleterious effects related to this chemotherapy.


Asunto(s)
Carya , Ciclofosfamida/farmacología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Testículo/metabolismo , Testículo/patología , Animales , Ácido Ascórbico/metabolismo , Catalasa/metabolismo , Ciclofosfamida/efectos adversos , L-Lactato Deshidrogenasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Modelos Animales , Nueces , Fitoterapia , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo , Testículo/efectos de los fármacos
17.
J Periodontol ; 82(10): 1442-52, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21563945

RESUMEN

BACKGROUND: The purpose of the present study is to verify a possible association between herpesviruses and periodontal pathogens in individuals with human immunodeficiency virus (HIV) and periodontitis. METHODS: Twenty-seven patients with HIV and chronic periodontitis and 23 patients with HIV and gingivitis were included in the study. Probing depth, clinical attachment loss, gingival index, and plaque index were recorded. Blood, saliva, and subgingival plaque were processed for viral and bacterial identification. Bacteria were identified by 16S rRNA-based polymerase chain reaction and viruses by the nested polymerase chain reaction. RESULTS: For the chronic periodontitis group, Epstein-Barr (EBV)-1 (70.4%) and Tannerella forsythia (Tf) (51.8%) presented higher detection in subgingival plaque and saliva (81.5% and 40.7%, respectively) than in blood (22% and 0%, respectively) (P <0.005 and P <0.0001, respectively). Porphyromonas gingivalis (Pg) was more frequent in subgingival plaque (77.7%; P <0.0001). In the gingivitis group, Pg and human cytomegalovirus (HCMV) presented higher frequency in subgingival plaque (95.6% and 91.3%, respectively; P <0.0001 and P = 0.004). Tf and EBV-1 were detected more frequently in subgingival plaque (47.8% and 78.3%, respectively) and saliva (52.2% and 52.2%, respectively; P = 0.004 and P <0.005) than in blood. EBV-1, EBV-1-HCMV, and presence of different viruses presented an association with periodontitis in saliva. CONCLUSIONS: No association was detected for herpesviruses and periodontal pathogens in patients who are HIV-positive with periodontitis. EBV-1 and coinfection (EBV-1-HCMV) were associated with patients who are HIV-positive with periodontitis.


Asunto(s)
Periodontitis Crónica/complicaciones , Periodontitis Crónica/virología , Gingivitis/complicaciones , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Herpesviridae/aislamiento & purificación , Adulto , Bacteroides/aislamiento & purificación , Distribución de Chi-Cuadrado , Periodontitis Crónica/sangre , Periodontitis Crónica/microbiología , Coinfección , Citomegalovirus/aislamiento & purificación , ADN Bacteriano/análisis , ADN Viral/análisis , Placa Dental/microbiología , Placa Dental/virología , Femenino , Gingivitis/sangre , Gingivitis/microbiología , Gingivitis/virología , Infecciones por VIH/sangre , Infecciones por VIH/microbiología , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Índice Periodontal , Porphyromonas gingivalis/aislamiento & purificación , Saliva/microbiología , Saliva/virología , Carga Viral
18.
J Periodontol ; 81(10): 1367-78, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20507230

RESUMEN

BACKGROUND: This study systematically evaluates the effect of occlusal overload (OV) on peri-implant tissue health in animal studies. METHODS: MEDLINE, EMBASE, and LILACS databases were searched for articles published up to and including January 2010. Studies that reported outcomes of non-splinted titanium dental implants submitted to OV were eligible for inclusion. Probing depth (PD), clinical attachment level (CAL), radiographic and histologic distances from the implant base to the most coronal point of bone-to-implant contact (RDIB and DIB, respectively), and bone density (BD) were the main outcomes of interest. RESULTS: Two controlled trials were included in this review and both were considered at a high risk of bias. The marked heterogeneity between studies did not allow data to be combined for meta-analyses. Two studies reported no association between OV and peri-implant tissue breakdown in the absence of dental plaque, with PD and CAL varying from 2 to 3 mm at the end of the experiments. In the presence of plaque accumulation, OV played a key role in peri-implant tissue breakdown (PD change: 5.3 mm; DIB: 6.0 mm). Trends suggested that OV may increase BD. CONCLUSIONS: Data on OV on stable implants are limited and conflicting. OV may lead to bone loss in the presence of dental plaque and to an increase in BD in areas where plaque control is performed.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Oclusión Dental Traumática/etiología , Prótesis Dental de Soporte Implantado/efectos adversos , Periimplantitis/etiología , Pérdida de Hueso Alveolar/diagnóstico por imagen , Animales , Oclusión Dental Traumática/complicaciones , Oclusión Dental Traumática/diagnóstico por imagen , Placa Dental/complicaciones , Modelos Animales , Oseointegración , Radiografía , Proyectos de Investigación
19.
Quintessence Int ; 41(5): 427-31, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20376379

RESUMEN

OBJECTIVE: To verify the effect of scaling and root planing on the antimicrobial activity of intracanal medications on the external root surface of periodontally compromised teeth. METHOD AND MATERIALS: Forty single-rooted extracted teeth were randomly assigned for visible calculus removal or scaling and root planing. Samples were separated into four groups-chlorhexidine, tetracycline hydrochloride, calcium hydroxide, or saline solution-and immersed in semisolid media and seeded with Micrococcus luteus for 24 hours. The zones of inhibition were measured using a profile projector. RESULTS: Calcium hydroxide and saline solution did not show bacterial growth inhibition. Chlorhexidine and tetracycline showed the occurrence of zones of inhibition in 70% and 40% of specimens, respectively. CONCLUSION: Partial antimicrobial activity on the external root surface was found when chlorhexidine and tetracycline solutions were used as intracanal medications; however, root planing procedures may modify this condition.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Periodontitis Crónica/terapia , Micrococcus luteus/efectos de los fármacos , Irrigantes del Conducto Radicular/administración & dosificación , Aplanamiento de la Raíz , Raíz del Diente/microbiología , Hidróxido de Calcio/administración & dosificación , Clorhexidina/administración & dosificación , Recuento de Colonia Microbiana , Preparaciones de Acción Retardada , Cálculos Dentales/terapia , Difusión , Pruebas Antimicrobianas de Difusión por Disco , Micrococcus luteus/crecimiento & desarrollo , Propiedades de Superficie , Tetraciclina/administración & dosificación
20.
Quintessence Int ; 41(2): 125-34, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20165744

RESUMEN

OBJECTIVE: To evaluate a comparison of open-flap debridement (OFD) with or without the use of enamel matrix proteins (EMP) for the treatment of infrabony defects. METHOD AND MATERIALS: Ten volunteers (38 infrabony defects) were randomized to receive OFD+EMP (test site) and OFD (control site). Clinical outcomes included mean changes in Plaque Index, Gingival Index, probing pocket depth (PPD), relative attachment level (RAL), gingival recession, width of keratinized tissue, and dental mobility at baseline and at 24 months. RESULTS: A significant reduction of 4.21+/-0.97 mm was observed in PPD for the OFD+EMP group (from 6.30+/-0.99 mm to 2.09+/-0.97 mm) and of 3.28+/-1.23 mm for the OFD group (from 6.13+/-0.88 mm to 2.85+/-1.42 mm) (P<.001). The reduction in PPD was statistically significantly greater for OFD+EMP compared to OFD (P=.03). The mean RAL decreased from 13.26+/-1.88 mm to 7.57+/-2.05 mm for the OFD+EMP group (a gain of 5.69+/-1.96 mm) and from 13.37+/-1.71 mm to 8.13+/-1.34 mm (P<.001) for the OFD group (a gain of 5.24+/-1.55 mm). Gingival recession was higher in the OFD+EMP group than in the OFD group. The mean keratinized tissue significantly decreased from 4.41+/-1.39 mm to 3.63+/-1.54 mm for OFD flap group (P<.01). CONCLUSION: Both treatment modalities were efficient in improving RAL and PPD. Within groups, there was a significant reduction in keratinized tissue for OFD and a significant postoperative recession for the OFD + EMP group. Infrabony defects treated with OFD + EMP showed significantly more PPD reduction when compared to OFD.


Asunto(s)
Pérdida de Hueso Alveolar/terapia , Periodontitis Crónica/terapia , Proteínas del Esmalte Dental/uso terapéutico , Desbridamiento Periodontal , Adulto , Pérdida de Hueso Alveolar/cirugía , Regeneración Ósea , Periodontitis Crónica/cirugía , Femenino , Recesión Gingival/etiología , Recesión Gingival/cirugía , Recesión Gingival/terapia , Humanos , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/cirugía , Pérdida de la Inserción Periodontal/terapia , Desbridamiento Periodontal/efectos adversos , Bolsa Periodontal/cirugía , Bolsa Periodontal/terapia , Proyectos Piloto , Estadísticas no Paramétricas , Resultado del Tratamiento
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