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1.
BMC Psychiatry ; 20(1): 381, 2020 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-32693789

RESUMEN

BACKGROUND: Anxiety disorders during pregnancy are not routinely assessed in Sri Lanka despite being common and being associated with adverse pregnancy outcomes. Screening can facilitate early detection and management of anxiety and improve pregnancy outcomes. Our aim was to determine the validity of the Sinhala translation of the Perinatal Anxiety Screening Scale (PASS) to detect anxiety among Sri Lankan pregnant women. METHODS: A cross-sectional study was conducted in antenatal clinics of a teaching hospital in Colombo District. The PASS was translated to Sinhala using the standard translation/ back-translation method. Pregnant women (n = 221) were sequentially recruited and assessed by a psychiatrist until 81 women with anxiety disorder were diagnosed using the International Classification of Diseases-10 criteria (gold standard). The Sinhala translation of the PASS (PASS-S) was administered to all recruited women, including 140 women without anxiety. Receiver-Operating- Characteristic (ROC) analysis was performed, the optimal cut-off score for PASS-S was determined, and its validity was assessed using sensitivity, specificity, predictive values and positive and negative likelihood ratios. Internal consistency was assessed using Cronbach's alpha. Test-retest and inter-rater reliability for PASS-S score and anxiety classification were assessed using intra class correlation coefficient (ICC) and Cohen's kappa (k), respectively. RESULTS: The mean age (±SD) of women was 30(±5.8) years, and 53.7% were multiparous. A psychiatrist diagnosed anxiety disorder was made in 37.0% of women, while the PASS-S, at its optimal cut-off of ≥20, classified 37.5% of women as having anxiety disorders. The area under the ROC curve for the PASS-S was 0.96 (95%CI 0.94-0.99). Sensitivity, specificity and positive and negative predictive values of the PASS-S were 0.93 (95% CI 0.84-0.97), 0.90 (95% CI 0.83-0.94), 0.85 (95% CI 0.75-0.90) and 0.95 (95% CI 0.89-0.98), respectively. Positive and negative likelihood ratios were 8.8 (95% CI 5.3-14.5) and 0.08 (95%CI 0.04-0.18), respectively, and the internal consistency was high (Cronbach's alpha 0.95). Four-factor structures obtained by exploratory factor analysis were "acute anxiety and adjustment", "social anxiety, specific fears and trauma", "perfectionism and control" and "general anxiety".Test-retest reliability was high for the PASS-S score (ICC 0.85[95% CI 0.65-0.96]) and anxiety classification (k 0.77[95% CI 0.34-1.2]). Inter-interviewer reliability was also high (ICC 0.92[95% CI 0.81-0.97] for the PASS-S score and (k0.86 [95% CI 0.59-1.1] for anxiety classification). CONCLUSION: The Sinhala translation of the PASS is a valid and reliable instrument to screen for anxiety disorders among antenatal women in Sri Lanka.


Asunto(s)
Trastornos de Ansiedad , Ansiedad , Adulto , Ansiedad/diagnóstico , Trastornos de Ansiedad/diagnóstico , Estudios Transversales , Femenino , Humanos , Embarazo , Psicometría , Reproducibilidad de los Resultados , Sri Lanka , Adulto Joven
2.
Phys Rev Lett ; 118(24): 246601, 2017 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-28665644

RESUMEN

Recent theoretical studies of topologically nontrivial electronic states in Kondo insulators have pointed to the importance of spin-orbit coupling (SOC) for stabilizing these states. However, systematic experimental studies that tune the SOC parameter λ_{SOC} in Kondo insulators remain elusive. The main reason is that variations of (chemical) pressure or doping strongly influence the Kondo coupling J_{K} and the chemical potential µ-both essential parameters determining the ground state of the material-and thus possible λ_{SOC} tuning effects have remained unnoticed. Here, we present the successful growth of the substitution series Ce_{3}Bi_{4}(Pt_{1-x}Pd_{x})_{3} (0≤x≤1) of the archetypal (noncentrosymmetric) Kondo insulator Ce_{3}Bi_{4}Pt_{3}. The Pt-Pd substitution is isostructural, isoelectronic, and isosize, and it therefore is likely to leave J_{K} and µ essentially unchanged. By contrast, the large mass difference between the 5d element Pt and the 4d element Pd leads to a large difference in λ_{SOC}, which thus is the dominating tuning parameter in the series. Surprisingly, with increasing x (decreasing λ_{SOC}), we observe a Kondo insulator to semimetal transition, demonstrating an unprecedented drastic influence of the SOC. The fully substituted end compound Ce_{3}Bi_{4}Pd_{3} shows thermodynamic signatures of a recently predicted Weyl-Kondo semimetal.

3.
Osteoporos Int ; 26(2): 521-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25209410

RESUMEN

SUMMARY: More than 45 % of long-term childhood cancer survivors (CCS) were diagnosed with osteopenia. Our data suggest that greater awareness for osteopenia is warranted in long-term CCS, especially in survivors who are older than 30 years, male, and underweight and were treated with cranial-spinal radiotherapy and/or steroids. INTRODUCTION: Osteopenia is a potential complication of childhood cancer treatment, but the magnitude of this problem in survivors is unknown. We examined (determinants of) bone mineral density (BMD) status in long-term survivors of adult childhood cancer. METHODS: This retrospective single-centre cohort study included 346 subjects with the most common types of childhood cancer. Subjects had a median age at diagnosis of 7.0 years (range 0.1-16.8 years), a median age at follow-up of 24.5 years (range 18.0-47.6 years) and a median follow-up time of 16.7 years (range 5.6-39.9 years). Total body BMD (BMDTB) and BMD of the lumbar spine (BMDLS) were measured by dual X-ray absorptiometry. Osteopenia was defined as BMD standardized deviation score (SDS) below -1. RESULTS: Survivors had a lower BMDTB and BMDLS (mean SDS -0.55; p<0.001 and -0.30; p<0.001, respectively) as compared to healthy peers. Osteopenia (BMDTB and/or BMDLS) was present in 45% of the survivors. Multivariate logistic regression analyses identified age at diagnosis<12 years, age>30 years at follow-up, male gender, underweight at follow-up and treatment with cranial-spinal radiotherapy or prednisone as independent prognostic factors for osteopenia. CONCLUSIONS: This large cohort of childhood cancer survivors identified osteopenia in 45% of CCS. This indicates that greater awareness is warranted, especially in survivors who are older than 30 years, male, have underweight and were treated with cranial-spinal radiotherapy and/or steroids.


Asunto(s)
Enfermedades Óseas Metabólicas/diagnóstico por imagen , Neoplasias/terapia , Absorciometría de Fotón , Adolescente , Adulto , Densidad Ósea/fisiología , Enfermedades Óseas Metabólicas/complicaciones , Niño , Preescolar , Femenino , Humanos , Lactante , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Sobrevivientes , Resultado del Tratamiento , Adulto Joven
4.
Nat Mater ; 12(12): 1096-101, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24056804

RESUMEN

The increasing worldwide energy consumption calls for the design of more efficient energy systems. Thermoelectrics could be used to convert waste heat back to useful electric energy if only more efficient materials were available. The ideal thermoelectric material combines high electrical conductivity and thermopower with low thermal conductivity. In this regard, the intermetallic type-I clathrates show promise with their exceedingly low lattice thermal conductivities. Here we report the successful incorporation of cerium as a guest atom into the clathrate crystal structure. In many simpler intermetallic compounds, this rare earth element is known to lead, through the Kondo interaction, to strong correlation phenomena including the occurrence of giant thermopowers at low temperatures. Indeed, we observe a 50% enhancement of the thermopower compared with a rare-earth-free reference material. Importantly, this enhancement occurs at high temperatures and we suggest that a rattling-enhanced Kondo interaction underlies this effect.

5.
Ann Oncol ; 23(6): 1626-32, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22048153

RESUMEN

BACKGROUND: Aim of this study was to investigate the long-term endocrine effects of treatment of childhood non-Hodgkin lymphoma (NHL). PATIENTS AND METHODS: A single-center cohort of 84 survivors (22 females) was included in this retrospective study. Median age was 21 years (9-40 years) and time after cessation of therapy 12 years (4-30 years). Height, weight, percentage fat, lean body mass (LBM), bone mineral content (BMC), bone mineral density of total body (BMD(TB)) and bone mineral density of lumbar spine (BMD(LS)) were measured. Thyroid-stimulating hormone (TSH), free thyroxin (fT4), insulin-like growth factor-1 (IGF-1), inhibin B and anti-müllerian hormone (AMH) levels were measured. Results were compared with Dutch controls. RESULTS: Height was lower in survivors [mean standard deviation score (SDS) -0.36, P = 0.002], but further analysis showed that shorter stature was already present at diagnosis (mean SDS -0.28, P = 0.023). Body mass index, percentage fat, BMC, BMD(TB) and BMD(LS) were not different from controls. LBM was lower in survivors (mean SDS -0.47, P = 0.008). TSH, fT4 and IGF-1 were normal in all survivors. Three of 20 adult females had low AMH levels and 23 of 42 adult males had low inhibin B levels. CONCLUSIONS: Twelve years after cessation of treatment, NHL survivors did not develop adiposity, osteoporosis or thyroid disease. Male survivors may be at risk for infertility.


Asunto(s)
Antineoplásicos/efectos adversos , Hormonas/sangre , Linfoma no Hodgkin/tratamiento farmacológico , Sobrevivientes , Adolescente , Adulto , Antineoplásicos/uso terapéutico , Composición Corporal , Pesos y Medidas Corporales , Densidad Ósea , Estudios de Casos y Controles , Niño , Preescolar , Sistema Endocrino/efectos de los fármacos , Femenino , Estudios de Seguimiento , Humanos , Vértebras Lumbares/diagnóstico por imagen , Linfoma no Hodgkin/sangre , Masculino , Radiografía , Adulto Joven
6.
Ned Tijdschr Tandheelkd ; 118(5): 277-81, 2011 May.
Artículo en Holandés | MEDLINE | ID: mdl-21661249

RESUMEN

'Dentures: A question of grinning and bearing it' is not just the title of a 25-year-old thesis, but it also reflects the content well. Dissatisfaction with complete dentures is not only determined by the quality of the dentures and the oral conditions, but also and just as much by the patient's capacity to adapt to and accept the dentures. In order to treat an edentulous patient adequately, an oral healthcare provider should pay special attention to these aspects. After 25 years of further scientific study, this conclusion is still true. The current care standard for edentulous patients with atrophy of the residual mandibular alveolar ridge is an overdenture supported by 2 implants. For edentulous patients with a solid residual mandibular alveolar ridge, conventional complete dentures are the first choice of treatment. Only in cases of obvious remaining complaints, should an implant-supported overdenture be considered.


Asunto(s)
Prótesis Dental de Soporte Implantado/métodos , Retención de Dentadura , Dentaduras , Arcada Edéntula/rehabilitación , Satisfacción del Paciente , Prótesis de Recubrimiento , Humanos
7.
Ned Tijdschr Tandheelkd ; 118(11): 563-7, 2011 Nov.
Artículo en Holandés | MEDLINE | ID: mdl-22235519

RESUMEN

When designing complete dentures, consideration should not only be given to the occlusal concept but also to the occlusal system as a whole. An important part of that system is the position of the artificial teeth. This prosthetic part of the occlusal system is directly related to the tongue, the floor of the mouth, the cheeks and the lips. The artificial teeth of the mandibular dentures have to be positioned in the so-called 'neutral zone' of the edentulous mandible. The neutral zone is the stress-free area between the tongue on one side and, on the other side, the mimic muscles, which are responsible for the movement of the lips and cheeks. Moreover, the maxillary posterior artificial teeth and the supporting acrylic surfaces of the maxillary denture have an important function in providing support for the upper lip and cheeks in order to prevent a 'denture look' appearance.


Asunto(s)
Oclusión Dental Balanceada , Diseño de Dentadura , Dentadura Completa , Bases para Dentadura , Humanos , Modelos Dentales
8.
Ann Oncol ; 21(5): 1121-6, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19850641

RESUMEN

BACKGROUND: Adult survivors of childhood cancer have been reported to have an increased risk of late sequels. A cluster of abnormalities that contribute to the metabolic syndrome may be expressed at a higher level and therefore result in an increased risk for diabetes mellitus and cardiovascular diseases. PATIENTS AND METHODS: We investigated a single-centre cohort of 500 adult survivors (228 females) of childhood cancer, median age 28 years (range 18-59 years) and median follow-up time 19 years (range 6-49 years). We measured total cholesterol, high-density lipoprotein-cholesterol, systolic and diastolic blood pressure, body mass index and the prevalence of diabetes mellitus. Data from the epidemiological Monitoring van Risicofactoren en Gezondheid in Nederland (MORGEN) study were used to calculate standard deviation scores as normative values. RESULTS: The criteria of the metabolic syndrome were met in 13% of the total cohort. Acute lymphoblastic leukaemia (ALL) survivors treated with cranial irradiation had an increased risk of developing the metabolic syndrome compared with ALL survivors not treated with cranial irradiation (23% versus 7%, P = 0.011), probably determined by higher prevalence of overweight and hypertension. CONCLUSION: Adult survivors of childhood cancer, especially those treated with cranial irradiation, are at increased risk of developing the metabolic syndrome.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Diabetes Mellitus/etiología , Síndrome Metabólico/etiología , Neoplasias/complicaciones , Neoplasias/terapia , Sobrevivientes , Adolescente , Adulto , Antineoplásicos/efectos adversos , Presión Sanguínea , Índice de Masa Corporal , Estudios de Cohortes , Terapia Combinada , Irradiación Craneana/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Pronóstico , Tasa de Supervivencia , Adulto Joven
9.
Endocr Connect ; 9(7): 676-686, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32567553

RESUMEN

PURPOSE: Augmented survival of childhood nephroblastoma and neuroblastoma has increased long-term side effects such as metabolic syndrome (MetS). Risk stratification is difficult after abdominal radiation because waist circumference underestimates adiposity. We aimed to develop a strategy for determining MetS in irradiated survivors using an integrated biomarker profile and vascular ultrasonography. METHODS: The NCEP-ATPIII MetS-components, 14 additional serum biomarkers and 9 vascular measurements were assessed in a single-centre cohort of childhood nephroblastoma (n = 67) and neuroblastoma (n = 36) survivors and controls (n = 61). Multivariable regression models were used to study treatment effects. Principal component analysis (PCA) was used to study all biomarkers in a combined analysis, to identify patterns and correlations. RESULTS: After 27.5 years of follow-up, MetS occurred more often in survivors (14%) than controls (3%). Abdominal radiotherapy and nephrectomy, to a lesser extent, were associated with MetS and separate components and with several biomarker abnormalities. PCA of biomarkers revealed a pattern on PC1 from favourable lipid markers (HDL-cholesterol, adiponectin) towards unfavourable markers (triglycerides, LDL-cholesterol, apoB, uric acid). Abdominal radiotherapy was associated with the unfavourable biomarker profile (ß = 1.45, P = 0.001). Vascular measurements were not of added diagnostic value. CONCLUSIONS: Long-term childhood nephro- and neuroblastoma survivors frequently develop MetS. Additional assessment of biomarkers identified in PCA - adiponectin, LDL, apoB, and uric acid - may be used especially in abdominally irradiated survivors, to classify MetS as alternative for waist circumference. Vascular ultrasonography was not of added value.

10.
Ned Tijdschr Tandheelkd ; 116(11): 593-6, 2009 Nov.
Artículo en Holandés | MEDLINE | ID: mdl-19999669

RESUMEN

Since there are many ways of preserving a natural dentition, if necessary with support of solitary crowns and fixed partial dentures, sometimes on dental implants, removable partial dentures are nowadays primarily indicated in patients with complaints about missing teeth in the aesthetic zone, which cannot be solved in another way. In addition to this, a removable partial denture is indicated in patients with extremely reduced dentitions or large or multiple edentulous areas, in patients with severe periodontitis or excessive loss of alveolar bone, in patients who are physically or emotionally vulnerable, as an interim solution on the way to edentulousness, as a temporary solution waiting for more extensive treatment and for patients who cannot afford an alternative.


Asunto(s)
Dentadura Parcial Removible , Estética Dental , Arcada Parcialmente Edéntula/terapia , Humanos , Higiene Bucal
11.
Crit Rev Oncol Hematol ; 133: 129-141, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30661649

RESUMEN

Over the past decades, survival rates of childhood cancer have increased considerably from 5 to 30% in the early seventies to current rates exceeding 80%. This is due to the development of effective chemotherapy, surgery, radiotherapy and stem cell transplantation, combined with an optimized stratification of therapy and better supportive care regimens. As a consequence, active surveillance strategies of late sequelae have been developed to improve the quality of survival. Several epidemiological studies have reported an increased incidence of (components of) metabolic syndrome (MetS) and cardiovascular disease in childhood cancer survivors (CCS). Growth hormone deficiency (GHD) after cranial radiotherapy (CRT) has been previously described as an important cause of MetS. New insights suggest a role for abdominal radiotherapy as a determinant for MetS as well. The role of other risk factors, such as specific chemotherapeutic agents, steroids, gonadal impairment, thyroid morbidity and genetics, warrants further investigation. This knowledge is important to define subgroups of CCS that are at risk to develop (subclinical) MetS features. These survivors might benefit from standard surveillance and early interventions, for example lifestyle and diet advice and medical treatment, thereby preventing the development of cardiovascular disease.


Asunto(s)
Supervivientes de Cáncer , Enfermedades Cardiovasculares/epidemiología , Síndrome Metabólico/epidemiología , Neoplasias/epidemiología , Adulto , Edad de Inicio , Supervivientes de Cáncer/estadística & datos numéricos , Enfermedades Cardiovasculares/etiología , Niño , Humanos , Incidencia , Síndrome Metabólico/complicaciones , Neoplasias/complicaciones , Factores de Riesgo
12.
J Dent Res ; 86(3): 276-80, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17314262

RESUMEN

Mandibular implant overdentures increase satisfaction and the quality of life of edentulous individuals. Long-term aftercare and costs may depend on the type of overdentures. One hundred and ten individuals received one of 3 types of implant-retained overdentures, randomly assigned, and were evaluated with respect to aftercare and costs. The follow-up time was 8 years, with only seven drop-outs. No significant differences (Kruskal-Wallis test) were observed for direct costs of aftercare (p = 0.94). The initial costs constituted 75% of the total costs and were significantly higher in the group with a bar on 4 implants, compared with the group with a bar on 2 implants and the group with ball attachments on 2 implants (p = 0.018). The last group needed a significantly higher number of prosthodontist-patient aftercare contacts, mostly for re-adjustment of the retentive system. It can be concluded that an overdenture with a bar on 2 implants might be the most efficient in the long term.


Asunto(s)
Prótesis Dental de Soporte Implantado/economía , Diseño de Dentadura/economía , Prótesis de Recubrimiento/economía , Arcada Edéntula/rehabilitación , Adulto , Anciano , Anciano de 80 o más Años , Análisis Costo-Beneficio , Implantación Dental Endoósea/economía , Retención de Dentadura/economía , Retención de Dentadura/instrumentación , Dentadura Completa Inferior/economía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Cuidados Posoperatorios/economía
13.
Ned Tijdschr Tandheelkd ; 112(9): 330-1, 2005 Sep.
Artículo en Holandés | MEDLINE | ID: mdl-16184909

RESUMEN

This article is focusing on incorporation of implant overdentures into the dental curriculum. For mandibular edentulism, an implant-retained overdenture should nowadays be considered a first choice for prosthodontic care, if not the standard of care. Yet, it is not incorporated in practical teaching today. Curriculum change is always difficult. The needs of our patients specifically, and those of society generally, should be primarily drivers of innovation of the curriculum. Therefore, Dutch dental schools should make sure that graduated students are experts in analyzing edentulous patients' problems, in considering possible treatments, and in carrying out the standard of care.


Asunto(s)
Prótesis Dental de Soporte Implantado , Educación en Odontología , Arcada Parcialmente Edéntula/terapia , Curriculum , Atención Odontológica/normas , Educación en Odontología/métodos , Educación en Odontología/normas , Humanos , Países Bajos
14.
Biomaterials ; 23(4): 1261-8, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11794323

RESUMEN

The osteoconductive properties of calcium phosphate cements (CPCs) may be improved by the addition of growth factors, such as recombinant human transforming growth factor-beta1 (rhTGF-beta1). Previously we have shown that rhTGF-beta1 was released from cement enriched with rhTGF-beta1 and subsequently stimulated the differentiation of pre-osteoblastic cells from adult rat long bones. It is unknown whether the addition of rhTGF-beta1 changes the material properties of this alpha-tricalcium-phosphate (alpha-TCP)/tetracalcium-phosphate-monoxide (TeCP)/dicalcium-phosphate-dihydrate (DCPD) cement, and what the characteristics of the release of rhTGF-beta1 from this CPC are. Therefore, in the present study we determined the release of rhTGF-beta1 from cement pellets in vitro. The possible intervening effects of the CPC modification for intermixing rhTGF-beta1 on physicochemical properties were studied by assessing the compressive strength and setting time, as well as crystallinity, calcium to phosphorus ratio, porosity and microscopic structure. Most of the previously incorporated rhTGF-beta1 in the cement pellets was released within the first 48 h. For all concentrations of rhTGF-beta1 intermixed (100 ng-2.5 mg/g CPC), approximately 0.5% of the amount of rhTGF-beta1 incorporated initially was released in the first 2 h, increasing to 1.0% after 48 h. The release of rhTGF-beta1 continued hereafter at a rate of about 0.1% up to 1 week, after which no additional release was found. The initial setting time, nor the final setting time was changed in control cement without rhTGF-beta1 (standard CPC) or in cement modified for rhTGF-beta1 (modified CPC) at 20 degrees C and 37 degrees C. Setting times were more than six times decreased at 37 degrees C compared to 20 degrees C. The compressive strength was initially low for both standard CPC and modified CPC, after which it increased between 24 h and 8 weeks. The compressive strength for the modified CPC was significantly higher compared with standard at 1, 2, and 8 weeks after mixing. X-ray diffraction revealed that both standard and modified CPC changed similarly from the original components into crystalline apatite. The calcium to phosphorus ratio as determined by an electron microprobe did not differ at all time points measured for standard CPC and modified CPC. In both standard CPC and modified CPC the separated particles became connected by crystals, forming a structure in which the particles could hardly be recognised in a densifying matrix with some small pores. The present study shows that the calcium phosphate cement is not severely changed by modification for the addition of rhTGF-beta1. The addition of rhTGF-beta1 in CPC enhances the biologic response as shown in our previous study and did not interfere with the aimed physical and chemical properties as shown in this study. We conclude that the addition of rhTGF-beta1 enlarges the potential of the CPC in bone replacement therapy.


Asunto(s)
Cementos para Huesos , Fosfatos de Calcio , Factor de Crecimiento Transformador beta/administración & dosificación , Animales , Fenómenos Químicos , Química Física , Fuerza Compresiva , Preparaciones de Acción Retardada , Humanos , Técnicas In Vitro , Ensayo de Materiales , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Ratas , Proteínas Recombinantes/administración & dosificación , Factor de Crecimiento Transformador beta1 , Difracción de Rayos X
15.
J Dent Res ; 73(12): 1858-64, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7814759

RESUMEN

When complete-denture wearers are treated with from four to six implants and mandibular implant-borne prostheses, masticatory performance improves. No significant improvement has been observed with two implants and implant-mucosa-borne overdentures, suggesting that the masticatory performance of edentulous subjects depends on the degree of support for their mandibular prostheses by implants or alveolar mucosa. To verify this hypothesis, we studied, in a randomized clinical trial, the comminution of an artificial test food during mastication. The trial involved the provision of a new maxillary denture and either a new conventional mandibular denture, a mandibular overdenture retained by two permucosal cylindric implants through a single bar-clip attachment, or a mandibular overdenture retained by a transmandibular implant through five clips on a triple-bar construction with cantilever extensions. In comparison with the subjects wearing mandibular implant-retained overdentures, the subjects with conventional complete dentures needed between 1.5 and 3.6 times more chewing strokes to achieve an equivalent reduction in particle size. No differences in masticatory performance and efficiency were found between the subjects who had received two permucosal cylindric implants and those who had received a transmandibular implant. The results suggest that the increased retention and stability of the mandibular denture, rather than the degree of support by implants or alveolar mucosa, determine the wearer's ability to comminute food during mastication.


Asunto(s)
Implantes Dentales , Retención de Dentadura/instrumentación , Dentadura Completa Inferior , Prótesis de Recubrimiento , Masticación , Adulto , Anciano , Implantación Dental Endoósea , Diseño de Prótesis Dental , Dentadura Completa Superior , Femenino , Alimentos , Humanos , Masculino , Persona de Mediana Edad , Tamaño de la Partícula , Siliconas , Estadísticas no Paramétricas
16.
J Dent Res ; 81(12): 856-9, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12454102

RESUMEN

In this prospective study, we determined the effects of the time interval between irradiation and implant therapy, implant location, bone-resection surgery, and irradiation dose on implant survival. We analyzed the survival of 446 implants inserted after radiotherapy over a period of up to 14 years in 130 consecutive patients treated for oral cancer. The 10-year overall Kaplan-Meier implant survival percentage is 78%. The difference in survival percentages of implants inserted < 1 year and >/= 1 year after irradiation (76% and 81%, respectively) is not significant. We concluded that implant survival is significantly influenced by the location (maxilla or mandible, 59% and 85%, respectively; p = 0.001), by the incidence of bone-resection surgery in the jaw where the implant was installed (p = 0.04), and by the irradiation dose at the implant site (< 50 Gray or >/= 50 Gray, p = 0.05).


Asunto(s)
Irradiación Craneana/efectos adversos , Implantación Dental Endoósea , Implantes Dentales , Fracaso de la Restauración Dental , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Mandíbula/cirugía , Maxilar/cirugía , Persona de Mediana Edad , Neoplasias de la Boca/radioterapia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Dosificación Radioterapéutica , Análisis de Supervivencia , Factores de Tiempo
17.
J Dent Res ; 72(6): 1001-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8496472

RESUMEN

In a randomized controlled clinical trial, 74 patients who required immediate dentures were randomly treated with immediate overdentures on two lower canines or with immediate complete dentures. Mandibular bone reduction was measured by use of oblique lateral cephalometric radiographs made at baseline and the results compared with those of one year and two years after denture treatment. Analysis of the data showed that the average bone reduction in the lower canine regions in the first year was 0.9 mm in the immediate-overdenture group and 1.8 mm in the immediate complete-denture group. In the posterior parts of the mandible, the bone reductions were, respectively, 0.7 mm and 1.9 mm. The differences were statistically significant in all measured regions. During the second year, no significant differences in bone reduction were found. The sums of differences in the first two years were significant in all regions except the molar region, preserving the initial difference. Retention of roots of canines beneath a mandibular denture in immediate denture patients, even when they were in poor condition, reduced the collapse of the alveolar processes in all regions of the mandible.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Dentadura Completa Inferior/efectos adversos , Prótesis de Recubrimiento/efectos adversos , Enfermedades Mandibulares/etiología , Diente Canino , Pilares Dentales , Dentadura Completa Inmediata/efectos adversos , Dentadura Parcial Inmediata/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
18.
J Dent Res ; 83(8): 630-3, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15271972

RESUMEN

Studies have shown that mandibular implant overdentures significantly increase satisfaction and quality of life of edentulous elders. Improved chewing ability appears to have a positive impact on nutritional state. Therefore, it is important to determine the best design of this prosthesis over the long term. In this randomized controlled trial, three groups of edentulous participants with atrophic mandibles wore 3 types of implant overdentures. During an eight-year follow-up, only seven of the 110 participants had dropped out of this study. Almost all participants were still satisfied with their overdentures. Participant satisfaction concerning retention and stability of the mandibular overdenture had decreased significantly in the two-implant ball attachment group, whereas the opinion of participants in the single- and triple-bar groups was still at the same level. The long-term results suggest that a mandibular overdenture retained by 2 implants with a single bar may be the best treatment strategy for edentulous people with atrophic ridges.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Prótesis Dental de Soporte Implantado , Prótesis de Recubrimiento , Mandíbula/cirugía , Satisfacción del Paciente , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Atrofia , Pilares Dentales , Diseño de Prótesis Dental , Ajuste de Precisión de Prótesis , Retención de Dentadura , Dentadura Completa Inferior , Femenino , Estudios de Seguimiento , Humanos , Arcada Parcialmente Edéntula/rehabilitación , Arcada Parcialmente Edéntula/cirugía , Masculino , Mandíbula/patología , Persona de Mediana Edad , Ajuste Social , Resultado del Tratamiento
19.
Physiol Behav ; 59(2): 265-71, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8838604

RESUMEN

The effects of environmental enrichment on motor activity, exploration and spatial performances were studied in young and old rats. Both young (4 mo old) and old (22 mo old) rats were housed from weaning to testing either in standard or in enriched conditions. All rats were submitted successively to spontaneous alternation test and to object exploration test. Results show that locomotion is decreased by age and enrichment but that the quality of exploration expressed by corrected alternation scores or by the response to spatial change is improved by enrichment sometimes in old, sometimes in young rats. Enrichment tends to accelerate the acquisition of spatial informations in young rats, but it does not succeed to restore the reactivity to spatial change of old rats in the object exploration test. These results, although they do not rule out a persistance of a continued behavioural plasticity during aging, also support the idea that the beneficial effects of environmental stimulations do not succeed to restore high cognitive function, such as the capacity to have a spatial representation, in old animals.


Asunto(s)
Envejecimiento/psicología , Conducta Exploratoria , Actividad Motora , Orientación , Medio Social , Animales , Masculino , Aprendizaje por Laberinto , Recuerdo Mental , Solución de Problemas , Ratas , Ratas Wistar , Retención en Psicología
20.
Eur J Clin Nutr ; 50 Suppl 2: S117-22, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8841792

RESUMEN

OBJECTIVE: To analyse the state of dentition and related aspects and to study their influence on the dietary intake of nutrients. DESIGN AND SUBJECTS: In the second cross-sectional measurement of SENECA's follow-up study, 12 research towns in 10 European countries and one town in Connecticut (USA) participated, involving 1424 elderly men and women born between 1913 and 1918. Dentition-related data were obtained from a general questionnaire; nutritional data were collected using a standardized modified dietary history. RESULTS: A large variation in the dental state existed among the towns. Women were more often edentulous and had fewer teeth. Self-reported chewing difficulties varied enormously. Most complaints were found in: women, edentulous subjects without dentures and in the towns in Spain, Portugal and Poland. More dentate women reported having visited their dentist. In the edentulous groups, differences between towns were small; for the dentate groups the percentage of dental visits varied from 0 in Coimbra (Portugal) to 96 in Mansfield (Connecticut/USA). For the edentulous subjects without any prosthetic supply, intakes of carbohydrate and vitamin B6 were significantly reduced. Also intakes of vitamin B1, vitamin C, dietary fibre, calcium and iron tended to be lower in this group. Town-dentition interactions existed for most nutrients. CONCLUSIONS: Substantial differences existed between towns in the influence of dentition on dietary intake.


Asunto(s)
Envejecimiento , Dentición , Encuestas Nutricionales , Fenómenos Fisiológicos de la Nutrición , Anciano , Estudios Transversales , Cuidado Dental para Ancianos , Dieta , Europa (Continente) , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Masculino , Masticación , Encuestas y Cuestionarios , Vitaminas/administración & dosificación
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