Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
1.
Int Endod J ; 50(3): 215-228, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26863893

RESUMO

AIM: To compare the clinical and radiographic efficacy of Biodentine™ , ProRoot® White Mineral Trioxide Aggregate (WMTA) and Tempophore™ as pulpotomy medicaments in the treatment of carious primary molars. METHODOLOGY: A parallel-design, randomized controlled trial was developed. Patients above 3 years of age with carious primary teeth with vital pulps without spontaneous pain or history of swelling were included. Fifty-eight patients (82 teeth) with a mean age of 4.79 ± 1.23 years were included. The teeth were randomized, blinded and allocated to one of the three groups (Biodentine™ , ProRoot® WMTA or Tempophore™ ) for pulpotomy treatment. All teeth were followed up clinically and radiographically (after 6, 12 and 18 months) by two blinded calibrated investigators. A generalized estimating equation (GEE), Wald chi-square test and an intention-to-treat analysis (ITT) with 'last carried forward' approach were performed using Statistical Package for Social Sciences v 21.0 (IBM Corp., Armonk, NK, USA). RESULTS: Forty-six patients and 69 teeth were available for follow-up after 18 months. Clinical success (radiographic success in parenthesis) was 95.24% (94.4%), 100% (90.9%) and 95.65% (82.4%) in the Biodentine™ , ProRoot® WMTA and Tempophore™ groups, respectively, but the difference was not significant. Pulp canal obliteration was significantly different amongst the experimental groups as the Biodentine™ group exhibited significantly more pulp canal obliteration when compared to the ProRoot® WMTA group at 6 months (P = 0.008) and 18 months (P = 0.003). CONCLUSIONS: After 18-month follow-up, there was no significant difference between Biodentine™ in comparison with ProRoot® WMTA or Tempophore™ .


Assuntos
Cárie Dentária/terapia , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Pulpotomia , Compostos de Alumínio , Compostos de Cálcio , Criança , Pré-Escolar , Creosoto , Cárie Dentária/diagnóstico por imagem , Combinação de Medicamentos , Feminino , Seguimentos , Humanos , Hidrocarbonetos Iodados , Análise de Intenção de Tratamento , Masculino , Dente Molar , Óxidos , Radiografia Dentária , Silicatos , Timol , Dente Decíduo , Resultado do Tratamento
2.
Eur Arch Paediatr Dent ; 25(2): 277-284, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38427158

RESUMO

PURPOSE: The study aimed to evaluate temporary fillings using Biodentine™ in asymptomatic deep carious lesions after 12, 24, and 36 months in school children from the remote village of Kerung, Nepal. METHODS: From November 2018 to November 2019, 91 temporary fillings were placed using Biodentine™ (a hydraulic calcium silicate cement) in permanent molars with deep carious lesions of schoolchildren in the remote district of Kerung, Nepal. These restorations were performed after selective caries removal in a non-dental setting with hand instruments and cotton roll isolation, as electric motors and saliva ejection systems were unavailable. In total, 78 single-surface and 13 multi-surface fillings were placed. Clinical and radiographic follow-up periods encompassed 12, 21, and 33 months, respectively. RESULTS: After 12 months, all single-surface fillings (100%) survived, whilst all multi-surface fillings were partially or entirely lost. The survival rate of single-surface restorations after 21 and 33 months was 67.6% and 50%, respectively. Radiographically, no pathology was observed. CONCLUSION: This study showed that Biodentine could be used in deep carious lesions as a temporary filling in single-surface lesions for at least up to 1 year and in a substantial number of cases for up to 21 and 33 months.


Assuntos
Compostos de Cálcio , Cárie Dentária , Silicatos , Humanos , Compostos de Cálcio/uso terapêutico , Cárie Dentária/terapia , Estudos Prospectivos , Criança , Seguimentos , Silicatos/uso terapêutico , Feminino , Masculino , Nepal , Restauração Dentária Temporária , Dente Molar , Dentição Permanente , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico
3.
Int Endod J ; 46(3): 198-204, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23136828

RESUMO

Several papers have been published to illustrate the effectiveness of mineral trioxide aggregate (MTA) as a pulpotomy medicament. Most of these reports do not offer a critical assessment on the data quality. Therefore, this review evaluated whether the currently available evidence is of an appropriate quality to support the long-term effectiveness of MTA as a pulpotomy medicament in primary molars using a standardized assessment criterion. A comprehensive literature search of human clinical outcome studies, which employed MTA as a pulpotomy medicament in primary teeth, was conducted using the MEDLINE database. Two independent observers rated these articles using the standardized assessment criteria. Furthermore, based on the initial sample mentioned in the individual studies and the sample included for the final analysis, the drop-out rates were calculated. Twenty-two studies were included for quality assessment with an excellent interobserver agreement. None of the 22 studies obtained grade A, four studies attained grade B1, five were graded B2 and 13 received grade C. Based on the assessment criteria employed, there was no evidence that MTA was better than present materials and techniques as a pulpotomy medicament. Furthermore, given the low quality of data, it is highly desirable to establish standard requisites for conducting and reporting on pulp therapy studies in primary teeth so as to benefit both researchers and clinicians to produce high-quality studies that are comparable and to prevent the misuse of clinical material and resources.


Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Óxidos/uso terapêutico , Pulpotomia/métodos , Irrigantes do Canal Radicular/uso terapêutico , Silicatos/uso terapêutico , Dente Decíduo/efeitos dos fármacos , Combinação de Medicamentos , Odontologia Baseada em Evidências , Humanos , Dente Molar/efeitos dos fármacos , Resultado do Tratamento
4.
Int Endod J ; 46(5): 434-41, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23094601

RESUMO

AIM: To evaluate the strengthening effect of two different types of fibre-reinforced composite (FRC) posts in an ex vivo experimental model. METHODOLOGY: Compact and hollow bone samples from bovine femurs were used as standardized samples. A total of 80 hollow samples were divided into two groups and filled either with a prefabricated FRC post or with individually adapted FRC posts. For each group, half of the samples were subjected to thermocycling (5-55 °C, 5000×). The remaining samples were kept for 24 h at 37 °C at 100% relative humidity. All samples were loaded diametrically until fracture. The null hypothesis tested was that the fracture resistance of standardized bone samples is not influenced by the type of FRC post, independently of the exposure to thermocycling. Results were evaluated by anova, and subsequent multiple comparisons were performed. RESULTS: The samples filled with the individually adapted FRC posts were more resistant to fracture than the prefabricated ones (P < 0.001), but this difference was not apparent in the thermocycled groups. Detachment of the posts upon fracture was highest after thermocycling for both groups, amounting to 55% and 95% for the individual adapted posts and the prefabricated posts, respectively. CONCLUSIONS: Initially, the samples filled with the individually adapted FRC posts were more resistant to fracture than those filled with the prefabricated ones. However, after ageing of the samples, both types of posts had similar strengthening effects.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Planejamento de Prótese Dentária , Fraturas Ósseas/fisiopatologia , Vidro/química , Técnica para Retentor Intrarradicular/instrumentação , Adesividade , Animais , Bis-Fenol A-Glicidil Metacrilato/química , Bovinos , Colagem Dentária , Resinas Epóxi/química , Fêmur/fisiopatologia , Umidade , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Polímeros/química , Polimetil Metacrilato/química , Distribuição Aleatória , Cimentos de Resina/química , Autocura de Resinas Dentárias , Estresse Mecânico , Temperatura , Fatores de Tempo
5.
Eur Arch Paediatr Dent ; 21(4): 509-518, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32519275

RESUMO

PURPOSE: To evaluate near-infrared light transillumination (NILT) for interproximal caries detection in children by comparing the correlation between both NILT and visual inspection (ICDAS) with bitewing (BW) radiography and by investigating possible differences in caries detection with NILT between primary and permanent teeth. METHODS: From 35 patients, 121 and 63 interproximal surfaces in, respectively, primary and permanent teeth were included. NILT images were obtained using DIAGNOcam™ (KaVo) and scored by two calibrated raters. A consensus diagnosis was reached for BW radiography; whereas, the ICDAS scores were obtained by one calibrated rater. Weighted Kappa (wκ) was used to evaluate inter- and intra-rater reliability of NILT and to evaluate the correlation between NILT, ICDAS and BW radiography. RESULTS: The correlation between NILT and BW radiography was moderate to substantial for primary teeth [Rater 1: wκ = 0.61 (95% CI = 0.49-0.75), Rater 2: wκ = 0.55 (95% CI = 0.41-0.69)] and fair for permanent teeth [Rater 1: wκ = 0.34 (95% CI = 0.15-0.53), Rater 2: wκ = 0.33 (95% CI = 0.08-0.58)]. The correlation between ICDAS and BW radiography was moderate for primary teeth [wκ = 0.49 (95% CI = 0.35-0.63)] and substantial for permanent teeth [wκ = 0.62 (95% CI = 0.32-0.92)]. No significant differences were found between primary and permanent teeth. CONCLUSION: NILT cannot be recommended as a single diagnostic tool for interproximal caries detection in primary teeth. The number of false negatives for dentine caries, especially in first primary molars, was too high. For the use in permanent teeth, NILT could be more accurate than BW radiography.


Assuntos
Cárie Dentária , Transiluminação , Criança , Humanos , Radiografia Interproximal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dente Decíduo
6.
J Oral Pathol Med ; 38(1): 1-17, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18771513

RESUMO

Dental agenesis is the most common developmental anomaly in humans and is frequently associated with several other oral abnormalities. Whereas the incidence of missing teeth may vary considerably depending on dentition, gender, and demographic or geographic profiles, distinct patterns of agenesis have been detected in the permanent dentition. These frequently involve the last teeth of a class to develop (I2, P2, M3) suggesting a possible link with evolutionary trends. Hypodontia can either occur as an isolated condition (non-syndromic hypodontia) involving one (80% of cases), a few (less than 10%) or many teeth (less than 1%), or can be associated with a systemic condition or syndrome (syndromic hypodontia), essentially reflecting the genetically and phenotypically heterogeneity of the condition. Based on our present knowledge of genes and transcription factors that are involved in tooth development, it is assumed that different phenotypic forms are caused by different genes involving different interacting molecular pathways, providing an explanation not only for the wide variety in agenesis patterns but also for associations of dental agenesis with other oral anomalies. At present, the list of genes involved in human non-syndromic hypodontia includes not only those encoding a signaling molecule (TGFA) and transcription factors (MSX1 and PAX9) that play critical roles during early craniofacial development, but also genes coding for a protein involved in canonical Wnt signaling (AXIN2), and a transmembrane receptor of fibroblast growth factors (FGFR1). Our objective was to review the current literature on the molecular mechanisms that are responsible for selective dental agenesis in humans and to present a detailed overview of syndromes with hypodontia and their causative genes. These new perspectives and future challenges in the field of identification of possible candidate genes involved in dental agenesis are discussed.


Assuntos
Anodontia/genética , Anodontia/classificação , Proteína Axina , Proteínas do Citoesqueleto/genética , Humanos , Fator de Transcrição MSX1/genética , Odontogênese/genética , Fator de Transcrição PAX9/genética , Fenótipo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Síndrome , Fator de Crescimento Transformador alfa/genética
8.
Community Dent Health ; 25(1): 33-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18435232

RESUMO

AIM: To investigate the impact of social indices on oral health and oral health behaviour in socially deprived adolescents and young adults in Flanders. METHOD: The study design was cross-sectional and included 68 subjects aged 12 to 26, who called for help by "Habbekrats", a non-profit organisation rendering assistance to adolescents and young adults living on the fringes of our society. The clinical oral examination was performed using criteria based on the diagnostic criteria for caries prevalence surveys published by BASCD. Information on parental occupational level, educational level, living condition and oral health behaviour was gained using questionnaires completed by the participants themselves and their social workers. RESULTS: The mean age was 16.2 years. Within the sample 92% and 90.8% respectively had a father or mother belonging to a low social level. For 68% of the sample the educational level was low. Concerning oral health behaviour 67% reported nutritional habits conducive to poor oral health whereas 64% reported good oral hygiene habits. The mean DMFS was 11.42 (SD = 14.33) and the mean care-index equalled 0.60 (SD = 0.39). Statistical analysis by means of a logistic regression model revealed that only the 'living condition' had a statistically significant influence on oral health behaviour (p < or = 0.05) and care-index (p < or = 0.05). There was no significant correlation between the parents occupation and subjects' educational level and the oral health behaviour and oral health status of the study group. CONCLUSION: From this analysis it is clear that 'living condition' had a significant influence on the oral health behaviour and care indices of the studied population of socially deprived adolescents.


Assuntos
Carência Cultural , Comportamentos Relacionados com a Saúde , Saúde Bucal , Meio Social , Adolescente , Adulto , Bélgica , Criança , Estudos Transversais , Índice CPO , Assistência Odontológica , Escolaridade , Comportamento Alimentar , Humanos , Ocupações , Higiene Bucal , Características de Residência , Classe Social , Escovação Dentária , Populações Vulneráveis
9.
Eur Arch Paediatr Dent ; 19(1): 1-22, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29372451

RESUMO

INTRODUCTION: Biodentine™ has frequently been acknowledged in the literature as a promising material and serves as an important representative of tricalcium silicate based cements used in dentistry. AIM: To provide an update on the physical and biological properties of Biodentine™ and to compare these properties with those of other tricalcium silicate cements namely, different variants of mineral trioxide aggregate (MTA) such as ProRoot MTA, MTA Angelus, Micro Mega MTA (MM-MTA), Retro MTA, Ortho MTA, MTA Plus, GCMTA, MTA HP and calcium enriched mixture (CEM), Endosequence and Bioaggregate™. STUDY DESIGN: A comprehensive literature search for publications from November 20, 2013 to November 20, 2016 was performed by two independent reviewers on Medline (PubMed), Embase, Web of Science, CENTRAL (Cochrane), SIGLE, SciELO, Scopus, Lilacs and clinicaltrials.gov. Electronic and hand search was carried out to identify randomised control trials (RCTs), case control studies, case series, case reports, as well as in vitro and animal studies published in the English language. CONCLUSIONS: The enhanced physical and biologic properties of Biodentine™ could be attributed to the presence of finer particle size, use of zirconium oxide as radiopacifier, purity of tricalcium silicate, absence of dicalcium silicate, and the addition of calcium chloride and hydrosoluble polymer. Furthermore, as Biodentine™ overcomes the major drawbacks of MTA it has great potential to revolutionise the different treatment modalities in paediatric dentistry and endodontics especially after traumatic injuries. Nevertheless, high quality long-term clinical studies are required to facilitate definitive conclusions.


Assuntos
Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Agentes de Capeamento da Polpa Dentária e Pulpectomia/química , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Silicatos/química , Silicatos/farmacologia , Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Animais , Combinação de Medicamentos , Humanos , Óxidos/química , Óxidos/farmacologia , Tamanho da Partícula
10.
Eur Arch Paediatr Dent ; 19(2): 129, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29546622

RESUMO

Owing to a misunderstanding on the part of the authors, the name of the last author, Prof. R. M. H. Verbeeck, was omitted from this article.

11.
Eur Arch Paediatr Dent ; 19(4): 245-253, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29949083

RESUMO

AIM: This was primarily to perform a retrospective analysis of 1000 emergency dental visits in order to characterize the nature of the dental emergency and the treatment provided and secondly to define a guideline for dental emergency treatment in children including pain management. MATERIALS AND METHODS: A retrospective review was conducted of 1000 patients (aged 0-16 years) who visited the dental emergency service of the paediatric dental clinic at the Ghent University Hospital, Belgium over a period of 3 years. Data regarding age, gender, reason for visit, year of visit, consequent appointments and treatment provided were collected. Statistical analysis was carried out using descriptive statistics (frequency distribution) and Chi-square test, with significance level set as P < 0.05. RESULTS: The number of patients visiting with a dental emergency increased annually. Approximately half (50.2%) of all paediatric dental emergency consultations were based on pain due to caries and its consequences. More than a quartile (26.7%) of emergency patients suffered from dental trauma of either primar or permanent teeth. The majority (96.7%) of the patients reported pain, 16.3% of the patients did not necessarily need immediate attention. CONCLUSION: Dental emergencies in a university hospital based setting were predominantly related to caries and trauma. A precise definition of dental emergencies is recommended in order to prevent abuse of paediatric emergency services.


Assuntos
Cárie Dentária/epidemiologia , Emergências/epidemiologia , Manejo da Dor , Traumatismos Dentários/epidemiologia , Adolescente , Distribuição por Idade , Bélgica , Criança , Pré-Escolar , Assistência Odontológica para Crianças , Cárie Dentária/complicações , Cárie Dentária/terapia , Unidade Hospitalar de Odontologia , Tratamento de Emergência , Feminino , Hospitais Universitários , Humanos , Lactente , Masculino , Manejo da Dor/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Traumatismos Dentários/terapia , Odontalgia/epidemiologia , Odontalgia/etiologia , Odontalgia/terapia
12.
Arch Oral Biol ; 52(2): 101-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17118335

RESUMO

Histological and ultrastructural observations of dentin of two patients affected with rare types of type I collagen disorders are presented. In the first case, a homozygous nonsense mutation in ADAMTS2 (substitution of a codon for tryptophan by a stopcodon) causes type VIIC Ehlers-Danlos syndrome (EDS) with multiple tooth agenesis and focal dysplastic dentin defects. In the second case, a missense mutation in COL1A1 (substitution of arginine by cysteine) results in a type I EDS phenotype with clinically normal-appearing dentition. Tooth samples are investigated by using light microscopy (LM), transmission electron microscopy (TEM) and immunostaining for types I and III collagen, and tenascin. These are compared with samples from patients with types III and IV osteogenesis imperfecta (OI) in association with dentinogenesis imperfecta (DI), showing a consistently abnormal appearance of the dentin in all specimens, with variations being primarily those of degree of change. Similarities in histological changes include the alternating presence of normal and severe pathological areas in primary and secondary dentin, the latter being characterized by large canal-like structures in atubular areas. Ultrastructural evidence of pathological dentinogenesis include abnormal distribution, size and organization of collagen fibers, which may also be found in clinically unaffected teeth. The histological and ultrastructural changes seen can be explained on the basis of odontoblast dysfunction which may be secondary to the collagen defect, interfering with different levels of odontoblast cell function and intercellular communication. These observations on (ultra)structural dentin defects associated with the two novel gene mutations are the first ever reported.


Assuntos
Colágeno Tipo I/ultraestrutura , Dentina/ultraestrutura , Dentinogênese Imperfeita/genética , Osteogênese Imperfeita/genética , Colágeno Tipo I/genética , Dentina/patologia , Dentinogênese Imperfeita/patologia , Humanos , Microscopia Eletrônica , Mutação/genética , Osteogênese Imperfeita/patologia , Descoloração de Dente/genética , Descoloração de Dente/patologia
13.
Dent Mater ; 33(4): e186-e203, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28196604

RESUMO

OBJECTIVES: Glass ionomer cements (GICs) are a subject of research because of their inferior mechanical properties, despite their advantages such as fluoride release and direct bonding to bone and teeth. Recent research aims to improve the bioactivity of the GICs and thereby improve mechanical properties on the long term. In this study, two types of bioactive glasses (BAG) (45S5F and CF9) are combined with GICs to evaluate the physico-chemical properties and biocompatibility of the BAG-GIC combinations. The effect of the addition of Al3+ to the BAG composition and the use of smaller BAG particles on the BAG-GIC properties was also investigated. MATERIALS AND METHODS: Conventional aluminosilicate glass (ASG) and (modified) BAG were synthesized by the melt method. BAG-GIC were investigated on setting time, compressive strength and bioactivity. Surface changes were evaluated by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), EDS and PO43- -and Ca2+ uptake in SBF. Biocompatibility of selected BAG-GICs was determined by a direct toxicity assay. RESULTS: The addition of BAG improves the bioactivity of the GIC, which can be observed by the formation of an apatite (Ap) layer, especially in CF9-containing GICs. More BAG leads to more bioactivity but decreases strength. The addition of Al3+ to the BAG composition improves strength, but decreases bioactivity. BAGs with smaller particle sizes have no effect on bioactivity and decrease strength. The formation of an Ap layer seems beneficial to the biocompatibility of the BAG-GICs. SIGNIFICANCE: Bioactive GICs may have several advantages over conventional GICs, such as remineralization of demineralized tissue, adhesion and proliferation of bone- and dental cells, allowing integration in surrounding tissue. CF9 BAG-GIC combinations containing maximum 10mol% Al3+ are most promising, when added in ≤20wt% to a GIC.


Assuntos
Cimentos de Ionômeros de Vidro , Força Compressiva , Materiais Dentários , Vidro , Teste de Materiais , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Dent Mater ; 32(11): 1414-1428, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27686260

RESUMO

OBJECTIVE: Bioactive glasses (BAG) form, in contrast to formerly used implant materials, a stable bond with tissues, especially bone, when implanted. Nowadays BAGs are often mixed with a cement/composite that hardens in situ to broaden its applications in dentistry or orthopedics. The bioactivity and biocompatibility of possible BAG candidates for BAG-cement/composite development were evaluated. METHODS: Two fluoride containing BAGs were tested: a Na+-containing (45S5F), based on the first commercial BAG, and a Na+-free BAG (CF9), with a higher Ca2+ and PO43- content. BAGs were tested on their bioactivity upon immersion in SBF for 7days by evaluating the surface changes by FT-IR, SEM, EDS and PO43- and Ca2+ uptake and/or release from SBF. Moreover, the biocompatibility of the BAGs was investigated with a direct contact cell viability study with HFF cells and a cell adhesion study with MG-63 cells. RESULTS: The Na+-free BAG, CF9, showed the highest potential to bioactivate cements because of its high Ca2+-release and apatite (Ap) formation, as evidenced by SEM pictures and corresponding EDX patterns. FT-IR confirmed the formation of an Ap layer. Moreover CF9 had a higher biocompatibility than 45S5F. SIGNIFICANCE: For the bioactivation of GICs/composites in order to enhance bonding and remineralization of surrounding tissues, fluoride containing BAG may have advantages over other BAGs as a more stable fluorapatite can be formed. CF9 may be an excellent candidate therefore.


Assuntos
Fluoretos , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos Ósseos , Implantes Dentários , Fibroblastos , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Biomaterials ; 21(13): 1373-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10850931

RESUMO

The effect of an early water contact on the fluoride release is studied for the resin-modified glass ionomer cements (RM-GIC) GC Lining LC, PhotacBond, Vitremer and Vitrebond and for the polyacid-modified composite resins (PAM-C) Variglass and Dyract. Six months fluoride release profiles were determined in regularly renewed water (37 degrees C), for the products directly after light curing and after 24 h maturation in a humid atmosphere (85% RH). ANOVA shows that both the short-term and the long-term fluoride release of a RM-GIC are influenced by this maturation. This indicates that direct water contact for this material should be avoided. For the RM-GIC a correlation is found between the initial fluoride release process and the long-term process. For the PAM-C materials, no differences in the fluoride release are found as a function of maturation, indicating that early water contact has no effect. The amounts of fluoride released by PAM-C are low compared to RM-GIC, which can affect their caries preventive potential. The results are explained on the basis of the setting reaction of both types of materials.


Assuntos
Resinas Acrílicas/química , Compômeros , Resinas Compostas/química , Fluoretos/química , Cimentos de Ionômeros de Vidro/química , Metacrilatos/química , Silicatos/química , Resinas Acrílicas/efeitos da radiação , Resinas Compostas/efeitos da radiação , Difusão , Cimentos de Ionômeros de Vidro/efeitos da radiação , Umidade , Luz , Teste de Materiais , Metacrilatos/efeitos da radiação , Fotoquímica , Silicatos/efeitos da radiação , Solubilidade , Fatores de Tempo , Água
17.
Biomaterials ; 21(5): 475-82, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10674812

RESUMO

This study investigates the fluoridation of four conventional glass ionomer cements (GIC) (ChemFil Superior encapsulated, Fuji Cap II, Ketac-Fil and Hi Dense) and three resin-modified GIC (RM-GIC) (Fuji II LC encapsulated, Photac-Fil and Vitremer). The fluoride release of matured restorative GIC was measured as a function of time, after four repeated fluoridations in a 2% NaF aqueous solution for 1 h. This release was corrected for the intrinsic release as determined with a control group. It was demonstrated that application of fluoride is capable of recharging GIC but the subsequent high fluoride release only lasts for one or a few days. Moreover, the fluoride release behaviour depends on the cement formulation. Comparable to the intrinsic release, the net fluoride release after fluoridation is composed of a short- and a long-term process, the former being predominant after fluoridation. The total amount of fluoride released according to the short-term process increases with consecutive fluoridations. This is especially pronounced for the RM-GIC, who exhibit a relatively slow release after fluoridation as compared to the conventional GIC. An explanation for these results is suggested on the basis of the physicochemistry of the setting reaction of the cements and of the fluoridation process.


Assuntos
Materiais Revestidos Biocompatíveis/química , Fluoretos/análise , Cimentos de Ionômeros de Vidro/química , Resinas Vegetais , Cápsulas , Cinética , Teste de Materiais
18.
Biomaterials ; 21(19): 2011-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10941923

RESUMO

The effect of 0.01 mol/l citrate solution at pH = 7 on the fluoride release is compared for the resin-modified glass ionomer cements (RM-GIC) GC Lining LC, PhotacBond, Vitremer and Vitrebond and for the polyacid-modified composite resins (PAM-C) Variglass and Dyract by means of the six-month fluoride release profiles at 37 degrees C. The fluoride release of both RM-GIC and PAM-C increases in the neutral citrate solution as compared to water, which can be explained by the ability of citrate to complex metal ions and hence to degrade the glass as well as the polysalt matrix of the cement. Although RM-GIC release more fluoride than PAM-C in water as well as in citrate solution, the relative increase in fluoride release upon immersion in citrate solution is most pronounced for PAM-C. Whereas for the latter citrate affects both the short-term and long-term fluoride release, for RM-GIC only the long-term fluoride release is affected. This suggests that the action of citrate increases with decreasing importance of the polysalt formation in the hardening of the material. This could be explained on the basis of the difference in the chemical properties of the cement matrix.


Assuntos
Compômeros , Fluoretos , Cimentos de Ionômeros de Vidro , Resinas Acrílicas , Resinas Compostas , Adesivos Dentinários , Fluoretos/análise , Metacrilatos , Resinas Vegetais , Silicatos
19.
J Dent Res ; 72(3): 577-81, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8450117

RESUMO

The present study investigated whether variability in fluoride release was reduced by use of a capsulated system as compared with a hand-mixed system based on the same qualitative and quantitative glass-ionomer formulation. Five operators independently prepared five disks of each type of glass-ionomer restorative filling material. The amount of fluoride released in water by each specimen after 1, 2, 3, 7, and 14 days was determined. The variance and the mean value of the fluoride release at a given time were independent of the operator, regardless of the glass-ionomer system considered. However, the variance and the mean value of the fluoride release at a given time were considerably greater for the capsulated system than for the hand-mixed system. A regression analysis further showed that the cumulative amount of fluoride released, [F], as a function of the time t conformed to [F] = a[1 - exp (-bt)] + ct0.5 for each glass-ionomer specimen, suggesting the simultaneous occurrence of two processes. Whereas the parameter b was the same for the hand-mixed and capsulated system and was independent of both a and c, the latter parameters were positively correlated. Moreover, the values for a and c were significantly greater for the capsulated system. On the basis of these results, it is concluded that the mixing process drastically influences the short-term as well as the long-term fluoride release.


Assuntos
Fluoretos/química , Cimentos de Ionômeros de Vidro/química , Cápsulas , Cromatografia , Restauração Dentária Permanente/métodos , Difusão , Fluoretos/análise , Cimentos de Ionômeros de Vidro/análise , Teste de Materiais , Pós , Análise de Regressão , Soluções , Fatores de Tempo
20.
Gen Hosp Psychiatry ; 19(2): 112-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9097065

RESUMO

The legal criteria for civil commitment dictates that individuals must be mentally ill, and either a danger to themselves, a danger to others, or substantially impaired in their ability to provide for their basic needs. These criteria, which have been adopted as medical necessity criteria by managed care programs, may result in a change in the clinical mix of the psychiatric inpatient population. The present study assesses the incidence of dangerousness among psychiatric inpatients and compares dangerous and nondangerous patients in terms of characteristics and treatment outcomes. The results indicate that for a large regional managed care program, 30% of psychiatric inpatients have a history of dangerousness in the past year. Patients who are rated as dangerous to others during admission have higher rates of complications for treatment and psychiatric disorders such as residential and vocational instability, family disruption, and higher premorbid dysfunction. They are also more likely to engage in disruptive and aggressive behavior during their hospital stays. Despite the higher incidence of acute and long-term dysfunction for dangerous patients, their hospitalization length of stay was comparable to that of patients not rated as dangerous.


Assuntos
Transtorno da Personalidade Antissocial/reabilitação , Internação Compulsória de Doente Mental/estatística & dados numéricos , Comportamento Perigoso , Programas de Assistência Gerenciada/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Grupos Diagnósticos Relacionados/estatística & dados numéricos , Feminino , Hospitais Psiquiátricos/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos/epidemiologia , Estudos Prospectivos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA