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1.
J Dent ; 93: 103268, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31881241

RESUMO

OBJECTIVES: The aim of this study was to assess the survival of composite restorations after selective (SCR) or total caries removal (TCR) and determine predictors of failures after 36 months. METHODS: 120 teeth with deep occlusal or occlusal-proximal carious lesions were randomly divided into control (TCR; n = 54; 69% Class II) and test (SCR; n = 66; 63% Class II) groups. Clinical evaluation was applied using the USPHS criteria, and the presence of Charlie or Delta scores at the marginal integrity were considered as a failure. RESULTS: The overall survival rate of restorations was 68% after 36 months, 81% for TCR and 57% for SCR (p = 0.004). The multivariable Cox Regression model demonstrated that restorations performed after SCR had 3.44 times greater probability of failure compared to TCR (p = 0.006). The other two predictors for failure of restorations were teeth with Class II cavities (hazard ratio = 3.3) and children with gingival bleeding over 20% (hazard ratio = 2.5). CONCLUSIONS: Performing composite restorations after SCR in primary teeth had success rate significantly lower than restorations performed after TCR. Complex cavities and worst patient´s oral hygiene were found to be predictors of failure of restorations. CLINICAL SIGNIFICANCE: Although SCR has been demonstrating high rates of pulp preservation, clinicians should consider that composite restorations fail in a higher frequency compared to TCR in primary teeth and, in some circumstances, may be preferable in terms of restoration longevity.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Criança , Resinas Compostas , Falha de Restauração Dentária , Humanos , Dente Decíduo
2.
J Dent ; 43(10): 1235-41, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26231301

RESUMO

OBJECTIVE: This randomized clinical trial aimed to compare the 24-months survival of composite restorations in primary molars after partial caries removal (PCR) and total caries removal (TCR). METHODS: Forty-eight children aged 3-8 years with at least one molar with a deep carious lesion were included (PCR; n=66; TCR; n=54). For PCR, excavation was stopped when dentine with a leathery consistency was achieved; in the TCR group, total absence of carious tissue was confirmed using a blunt-tipped probe. Pulpotomy was performed in cases of pulp exposure. Success was assessed by modified USPHS criteria with Alpha and Bravo scores recorded as success. RESULTS: Pulp exposure occurred in 1 and 15 of the teeth treated with PCR and TCR respectively (p<0.01). The restorations survival rate after 24 months was 66% (PCR) and 86% (TCR) (p=0.03). When teeth that received pulpotomy were analyzed separately, the survival rate was 92% (p=0.09). PCR performed in occlusoproximal restorations demonstrated the lowest success rate (p=0.002). PCR increases 2.90 times the probability of having a restorative failure compared to TCR (p=0.03), after adjusting for cavity type. When pulp exposure and restoration failure were considered as the outcome, there was no significant difference between the two groups (p=0.10) with success rates of 64% (PCR) and 61% (TCR). CONCLUSION: Collectively, deciduous teeth submitted to PCR prevented pulp exposure and, consequently, more invasive treatments; otherwise, PCR yielded lower longevity for composite restoration compared to TCR, suggesting that PCR restorations need to be followed over time, especially when multi-surface restorations are involved. CLINICAL SIGNIFICANCE: Composite restorations on carious remaining tissue require monitoring over time, especially those performed in more than one surface. Even if the restorations present shortcomings over the time, the majority of them are subject to repair, allowing more conservative approaches for teeth with deep caries lesions.


Assuntos
Resinas Compostas/uso terapêutico , Cárie Dentária/terapia , Restauração Dentária Permanente/métodos , Dente Decíduo/patologia , Criança , Pré-Escolar , Preparo da Cavidade Dentária , Exposição da Polpa Dentária/patologia , Exposição da Polpa Dentária/prevenção & controle , Falha de Restauração Dentária , Dentina/patologia , Feminino , Humanos , Masculino , Dente Molar/patologia , Pulpotomia , Resultado do Tratamento
3.
J Dent Res ; 92(1): 51-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23114032

RESUMO

The discovery that dental pulp stem cells are capable of differentiating into endothelial cells raises the exciting possibility that these cells can be a single source of odontoblasts and vascular networks in dental tissue engineering. The purpose of this study was to begin to define signaling pathways that regulate endothelial differentiation of SHED. Stem cells from exfoliated deciduous teeth (SHED) exposed to endothelial growth medium (EGM-2MV) supplemented with vascular endothelial growth factor (VEGF) differentiated into VEGFR2-positive and CD31-positive endothelial cells in vitro. In vivo, VEGFR1-silenced SHED seeded in tooth slice/ scaffolds and transplanted into immunodeficient mice showed a reduction in human CD31-positive blood vessels as compared with controls (p = 0.02). Exposure of SHED to EGM2-MV supplemented with VEGF induced potent activation of ERK and Akt signaling, while it inhibited phosphorylation of STAT3. Notably, genetic (MEK1 silencing) or chemical (U0126) inhibition of ERK signaling restored constitutive STAT3 phosphorylation and inhibited the differentiation of SHED into endothelial cells. Collectively, analysis of these data unveiled the VEGF/MEK1/ERK signaling pathway as a key regulator of the endothelial differentiation of dental pulp stem cells.


Assuntos
Polpa Dentária/citologia , Células Endoteliais/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Células-Tronco/fisiologia , Dente Decíduo/citologia , Animais , Vasos Sanguíneos/imunologia , Butadienos/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Meios de Cultura , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inativação Gênica/fisiologia , Humanos , MAP Quinase Quinase 1/genética , MAP Quinase Quinase Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Knockout , Camundongos SCID , Nitrilas/farmacologia , Proteína Oncogênica v-akt/efeitos dos fármacos , Fosforilação , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Fator de Transcrição STAT3/antagonistas & inibidores , Alicerces Teciduais , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
4.
J Dent Child (Chic) ; 78(3): 131-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22126924

RESUMO

PURPOSE: The purpose of this in vitro study was to evaluate, via scanning electron microscopy, the micromorphology of the dentine walls of primary anterior teeth with focus on the presence of the smear layer after endodontic debridement and final irrigation with different systems. METHODS: Thirty primary maxillary anterior teeth were assigned to 3 groups according to the final irrigant solution. Group 1 received 1% sodium hypochlorite; Group 2 received 17% EDTA followed by 1% sodium hypochlorite; and Group 3 received 6% citric acid followed by 1% sodium hypochlorite. The canals were debrided using 1% sodium hypochlorite to a size 30 file, and the final irrigation was performed with one of the 3 irrigants as assigned. The teeth were prepared for examination of the canal walls by electron microscopy for the presence or absence of the smear layer. RESULTS: Group 1 had significantly higher scores for remaining smear layer than Groups 2 and 3 (P<.01), while Groups 2 and 3 presented similar smear layer score values. CONCLUSIONS: Sodium hypochlorite promoted the formation of a smear layer during shaping, and the use of EDTA and citric acid facilitated smear layer removal.


Assuntos
Ácido Cítrico/farmacologia , Ácido Edético/farmacologia , Irrigantes do Canal Radicular/farmacologia , Preparo de Canal Radicular/métodos , Camada de Esfregaço , Dente Decíduo , Ácido Cítrico/administração & dosagem , Desbridamento , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/ultraestrutura , Ácido Edético/administração & dosagem , Humanos , Técnicas In Vitro , Maxila , Microscopia Eletrônica de Varredura , Irrigantes do Canal Radicular/administração & dosagem , Hipoclorito de Sódio/administração & dosagem , Hipoclorito de Sódio/farmacologia , Soluções/farmacologia , Estatísticas não Paramétricas , Irrigação Terapêutica
5.
J Dent Res ; 89(6): 603-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20351355

RESUMO

It is known that stem cells from exfoliated deciduous teeth (SHED) can be induced to differentiate into odontoblasts. However, the nature of dentin-derived morphogenic signals required for dental pulp stem cell differentiation remains unclear. The hypothesis underlying this work is that dentin-derived Bone Morphogenetic Proteins (BMP) are necessary for the differentiation of SHED into odontoblasts. We observed that SHED express markers of odontoblastic differentiation (DSPP, DMP-1, MEPE) when seeded in human tooth slice/scaffolds and cultured in vitro, or implanted subcutaneously into immunodeficient mice. In contrast, SHED cultured in deproteinized tooth slice/scaffolds, or scaffolds without a tooth slice, do not express these markers. SHED express the BMP receptors BMPR-IA, BMPR-IB, and BMPR-II. Notably, blockade of BMP-2 signaling inhibited the expression of markers of odontoblastic differentiation by SHED cultured in tooth slice/scaffolds. Collectively, this work demonstrates that dentin-derived BMP-2 is required to induce the differentiation of SHED into odontoblasts.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Dentina/enzimologia , Odontoblastos/efeitos dos fármacos , Animais , Anticorpos Neutralizantes/farmacologia , Biomarcadores/análise , Western Blotting , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Proteína Morfogenética Óssea 7/antagonistas & inibidores , Proteína Morfogenética Óssea 7/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/análise , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/análise , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Polpa Dentária/citologia , Proteínas da Matriz Extracelular/análise , Glicoproteínas/análise , Humanos , Camundongos , Camundongos SCID , Fosfoproteínas/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/análise , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia , Tela Subcutânea/cirurgia , Alicerces Teciduais , Dente Decíduo/citologia
6.
J Dent Child (Chic) ; 76(3): 223-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19941765

RESUMO

PURPOSE: The purpose of this study was to investigate dentin rehardening in the remaining carious dentin after indirect pulp treatment (IPT) using microhardness analysis after 37 to 71 months. METHODS: Eighteen teeth submitted to IPT and capped with calcium hydroxide (CH) or gutta-percha (GP) were evaluated (treated group). Ten sound molars and 10 molars with deep acute carious lesions were selected to serve as positive and negative control groups, respectively. In the treated group, restorations and pulp-capping materials were removed. In the positive control group, 3- to 4-mm deep cavities were prepared. In the negative control group, the carious tissue was removed. Microhardness analysis was performed at 10-, 35-, 60-, 85-, and 110-microm depths. Data were analyzed using 1-way analysis of variance (P<.05). RESULTS: Microhardness values for sound, carious, and treated groups at 10-, 35-, 60-, 85-, and 110-microm depths showed a statistically significant difference (P

Assuntos
Capeamento da Polpa Dentária/métodos , Dentina/fisiopatologia , Hidróxido de Cálcio/uso terapêutico , Criança , Cárie Dentária/terapia , Guta-Percha/uso terapêutico , Dureza , Humanos , Dente Molar , Esfoliação de Dente , Remineralização Dentária/métodos , Dente Decíduo
7.
Dentomaxillofac Radiol ; 36(7): 377-81, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17881594

RESUMO

OBJECTIVES: This study investigated grey levels and radiolucent lesion depth as cavity predictors for approximal dentin caries lesions in primary teeth. METHODS: 51 children (4-10 years old), presenting with radiolucency in the outer half of the dentin on the approximal surfaces of deciduous molar teeth and approximal anatomic contact with the adjacent tooth (without restoration or cavitated caries lesion), participated in the study. Bitewing radiographs were made, and temporary tooth separation was performed and an impression taken to detect cavitation. Radiographs were scanned (300 dpi) and grey levels were measured in carious and sound dentin. Impressions were also scanned and the size of cavity opening was measured in square millimetres. RESULTS: Grey levels of carious dentin (115.27+/-33.52) were significantly lower compared with sound dentin (151.88+/-30.99). No significant differences were observed in the dentin degree of radiolucency between "cavitated" and "non-cavitated" carious dentin. Cavitated lesions showed deeper radiolucent lesions compared with non-cavitated ones (P=0.03). There was no association between the size of cavitation and radiolucent lesion depth. CONCLUSIONS: Grey levels did not indicate cavitation in the outer half of the approximal dentin lesions. However, extension of a radiolucent lesion deep into the outer half of the dentin was associated with cavitated lesions independently of the size of cavitation. A computer-aided image analysis may help clinicians in monitoring caries progression and evaluating the probability of occurrence of cavitated caries lesions.


Assuntos
Cárie Dentária/diagnóstico por imagem , Dentina/diagnóstico por imagem , Dente Decíduo/diagnóstico por imagem , Absorciometria de Fóton , Criança , Pré-Escolar , Esmalte Dentário/diagnóstico por imagem , Técnica de Moldagem Odontológica , Previsões , Humanos , Processamento de Imagem Assistida por Computador , Dente Molar/diagnóstico por imagem , Radiografia Interproximal , Radiografia Dentária Digital , Reprodutibilidade dos Testes
8.
Refuat Hapeh Vehashinayim (1993) ; 19(4): 6-16, 67, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12510251

RESUMO

The aims of the present article were to assess the reliability of different techniques to assess marginal defects in Class II restorations in retrieved primary molars, and to determine the degree of agreement between the various assessment modalities. The material evaluated was comprised of 18 exfoliated primary molars that had been restored 20 to 22 months previously with a resin-modified glass ionomer (Vitremer--7 teeth), a hybridized composite resin (Z100 + Scotchbond Multipurpose--9 teeth), and amalgam (Dispersalloy--2 teeth). No significant differences could be observed between the groups. The majority of the restorations rated A at the buccal and lingual margins, but poor adaptation was disclosed at the cervical margin of the three types of restorations. SEM evaluation revealed that the highest percentage of defects was seen at the cervical margins with no statistically significant difference between the groups. No or minimal leakage was present at the occlusal margins and severe penetration of dye was seen at the cervical margins in all groups. Significantly less demineralization was seen adjacent to the Vitremer and Z100 restorations when compared to the Dispersalloy but no difference was found between the esthetic restorations. Except for the visual tactile examination, small marginal defects could be disclosed by the three assessment techniques (SEM, dye penetration, and polarized light microscopy). A good degree of agreement was observed between the three evaluation techniques.


Assuntos
Adaptação Marginal Dentária , Materiais Dentários/química , Restauração Dentária Permanente/classificação , Dente Molar/patologia , Dióxido de Silício , Dente Decíduo/patologia , Zircônio , Criança , Corantes , Compômeros/química , Resinas Compostas/química , Ligas Dentárias/química , Amálgama Dentário/química , Infiltração Dentária/classificação , Adesivos Dentinários/química , Cimentos de Ionômeros de Vidro/química , Humanos , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Dente Molar/ultraestrutura , Técnicas de Réplica , Reprodutibilidade dos Testes , Cimentos de Resina/química , Estatística como Assunto , Propriedades de Superfície , Colo do Dente/patologia , Colo do Dente/ultraestrutura , Desmineralização do Dente/classificação , Dente Decíduo/ultraestrutura
9.
Sao Paulo Med J ; 119(4): 142-5, 2001 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-11500788

RESUMO

CONTEXT: Routine immunization of groups at high risk for influenza has been progressively implemented as a matter of Brazilian public health policy. Although the benefits of the vaccination for healthy young adults are still controversial, it has been offered yearly to hundreds of thousands of Brazilian workers, generally as part of wellness initiatives in the workplace. OBJECTIVE: To study the characteristics of subjects that accepted or refused to be vaccinated against influenza and to report on respiratory symptoms in both groups, one year after the campaign date. DESIGN: A prospective observational study. SETTING: Workers at a subsidiary of an international bank in São Paulo, Brazil. PARTICIPANTS: 124 persons that did not accept and 145 that voluntarily accepted the vaccine completed 12 months of follow-up. MAIN MEASUREMENTS: Data concerning gender, age, tobacco use, and any history of chronic respiratory illness such as asthma, bronchitis, rhinitis, and repetitive upper-respiratory infections, were recorded at the time of vaccination. After that, workers were asked monthly by questionnaire or telephone about respiratory symptoms, days of work lost and medical consultations. RESULTS: The results showed statistically significant differences regarding age (P = 0.004) with the vaccinated group (V) being younger than the non-vaccinated (NV) one, and with reference to previous repetitive upper-respiratory infections being higher among the V group (P < 0.0001). During the follow-up, the V group reported more occurrences of upper respiratory symptoms (P < 0.0001), due to both non-influenza (P < 0.0001) and influenza-like illness (P = 0.045). Differences were also found between V and NV groups concerning days off work and number of medical consultations due to upper-respiratory symptoms and non-influenza illness. Gender and history of repetitive upper-respiratory infections were the best predictors of influenza-like illness-related events. CONCLUSIONS: The making of previous reference to repetitive upper-respiratory infections was a major difference between those who accepted or rejected the vaccine. The vaccination itself was not sufficient to reduce the number of occurrences of respiratory symptoms and related absenteeism to levels similar to those found among non-vaccinated people.


Assuntos
Promoção da Saúde , Vacinas contra Influenza/administração & dosagem , Aceitação pelo Paciente de Cuidados de Saúde , Doenças Respiratórias/epidemiologia , Vacinação , Adulto , Brasil/epidemiologia , Feminino , Seguimentos , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Masculino , Estudos Prospectivos , Doenças Respiratórias/prevenção & controle , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle
10.
Pediatr Dent ; 22(6): 479-85, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11132507

RESUMO

PURPOSE: The aim of the study was to access the clinical performance of two esthetic materials (Vitremer and Z100 + Scotchbond Multipurpose) when used as Class II restorations in primary molars, and compare them to amalgam controls. METHODS: A total of 102 restorations were placed in primary molars of 29 schoolchildren; 40 were of Vitremer, 38 of Z100 + Scotchbond Multipurpose, and 24 of amalgam (Dispersalloy). The restorations were evaluated clinically at baseline and after 6, 12, 18, 24 months, or until tooth exfoliation or patient drop-out, following the modified Cvar and Ryge criteria. Radiographs were taken at yearly intervals, and the radiograph of the last examination available was assessed and scored. RESULTS: The majority of the restorations examined clinically up to 18 months was good (Alpha according to Cvar and Ryge), and no statistically significant differences between the groups was observed. However, at the 19-24 months evaluation, Z100 rated better than Vitremer for surface appearance and color match. The prevalence of radiolucent defects at the cervical margin for the Z100 (47%) was significantly higher than for amalgam (11%) restorations (P = 0.002) and for Vitremer (13%) restorations (P = 0.008). CONCLUSION: The three materials evaluated (Vitremer, Z100 and Dispersalloy) presented satisfactory clinical performance during the time evaluated (approximately 2 years). Approximately half of the composite resin restorations presented radiographic defects that might require replacement at a later date. In contrast, glass ionomer and amalgam restorations presented significantly less radiographic defects at the time of the final examination. This study suggests that composite resins are indicated for classII restorations in primary molars that are expected to exfoliate within two years.


Assuntos
Resinas Compostas , Restauração Dentária Permanente/classificação , Estética Dentária , Cimentos de Ionômeros de Vidro , Dente Molar , Cimentos de Resina , Dente Decíduo , Análise de Variância , Distribuição de Qui-Quadrado , Criança , Cor , Resinas Compostas/química , Ligas Dentárias/química , Amálgama Dentário/química , Adaptação Marginal Dentária , Adesivos Dentinários/química , Feminino , Seguimentos , Cimentos de Ionômeros de Vidro/química , Humanos , Masculino , Dente Molar/diagnóstico por imagem , Dente Molar/patologia , Prevalência , Radiografia , Dióxido de Silício/química , Estatísticas não Paramétricas , Propriedades de Superfície , Colo do Dente/diagnóstico por imagem , Colo do Dente/patologia , Esfoliação de Dente , Dente Decíduo/diagnóstico por imagem , Dente Decíduo/patologia , Zircônio/química
11.
J Clin Pediatr Dent ; 24(1): 9-15, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10709536

RESUMO

Bruxism occurs in nearly 60% of children between 3 and 5 years, with important repercussions to the different components of the stomatognathic system. Nevertheless, there is little information in the literature about this topic. The aim of this study was to compare two groups of children with bruxism. One group was not submitted to treatment, serving as a control. To the other group, nocturnal bite plate was made. Cast models were made for both groups, to evaluate the progression of wear facets, during 8 months. The results are as follows: The 4 children of the control group displayed increased wear facets during the study period. On the other hand, of the 5 children that used nocturnal bite plate, showed no increase of wear facets, even after the removal of the device. From this study, we can conclude that the use of nocturnal bite plate is efficient against bruxism in 3- to 5-year-old children.


Assuntos
Bruxismo/prevenção & controle , Placas Oclusais , Abrasão Dentária/prevenção & controle , Bruxismo/complicações , Pré-Escolar , Humanos , Sono , Abrasão Dentária/etiologia
12.
Pediatr Dent ; 19(4): 253-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9200196

RESUMO

This study determined the shear bond strength of resin composites to primary dentin using three dentin adhesives and the presence or absence of a hybrid zone. The buccal and lingual surfaces of 40 recently extracted noncarious primary teeth were ground flat with SiC paper ending with the 600 grit. The teeth were divided at randomly into eight groups of five teeth (10 surfaces) each: 1) Unetched dentin, dry dentin, All-Bond 2/Bis-Fil P; 2) Unetched dentin, moist dentin, All-Bond 2/Bis-Fil P; 3) Dentin etched for 15 sec with 10% phosphoric acid, dry dentin, All-Bond 2/Bis-Fil P; 4) Dentin etched for 15 sec with 10% phosphoric acid, moist dentin, All-Bond 2/Bis-Fil P; 5) Dentin etched with 10% maleic acid for 15 sec, dry dentin, Scotchbond Multi-Purpose/Z100; 6) Dentin etched with 10% maleic acid for 15 sec, moist dentin, Scotchbond Multi-Purpose/Z100; 7) Dentin etched with 10 citric acid/3% ferric chloride, dry dentin, Amalgambond Plus/Z100; 8) Dentin etched with 10 citric acid/3% ferric chloride, moist dentin, Amalgambond Plus/Z100. All teeth were thermocycled 1000x (5 and 55 degrees C, 30-sec dwell time), and shear bond strength testing was conducted using an Instron (crosshead speed 0.5 mm/min). Failure sites after debonding were examined with the SEM. For each group, one additional tooth was used to prepare two class V cavities (one facial and one lingual) restored according to the specification in each group, sectioned buccolingually and examined with the SEM. The results, in MPa, were: 1) 12.55 +/- 5.97; 2) 10.41 +/- 6.16; 3) 9.94 +/- 7.26; 4) 12.25 +/- 4.70; 5) 13.02 +/- 8.01; 6) 16.51 +/- 8.62; 7) 12.51 +/- 8.95; 8) 17.93 +/- 6.44. ANOVA and Student-Newman-Keuls tests showed no statistically significant differences. SEM evaluation showed that the smear layer was removed in all groups exposing primary dentin tubules infiltrated by resin. A resin-reinforced hybrid layer was readily seen in all specimens.


Assuntos
Compostos Inorgânicos de Carbono , Colagem Dentária , Adesivos Dentinários/química , Dentina/ultraestrutura , Cimentos de Resina , Dente Decíduo/ultraestrutura , Condicionamento Ácido do Dente , Adesivos/química , Análise de Variância , Carbono , Cloretos , Ácido Cítrico/administração & dosagem , Resinas Compostas/química , Preparo da Cavidade Dentária/classificação , Restauração Dentária Permanente , Análise do Estresse Dentário , Compostos Férricos/administração & dosagem , Humanos , Maleatos/administração & dosagem , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos/administração & dosagem , Compostos de Silício , Dióxido de Silício/química , Camada de Esfregaço , Estresse Mecânico , Propriedades de Superfície , Termodinâmica , Fatores de Tempo , Zircônio/química
13.
Quintessence Int ; 28(10): 677-80, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9477888

RESUMO

This report describes a young patient with fusion of a maxillary central incisor to a supernumerary tooth. Treatment involved extraction of the fused tooth and orthodontic movement of the lateral incisor to occupy the position of the extracted tooth. A resin composite laminate veneer was placed on the lateral incisor to simulate the appearance of a central incisor. Five years of follow-up revealed that treatment had successfully restored esthetics and function.


Assuntos
Estética Dentária , Dentes Fusionados/terapia , Incisivo/anormalidades , Criança , Resinas Compostas/uso terapêutico , Facetas Dentárias , Seguimentos , Humanos , Masculino , Maxila , Ortodontia Corretiva , Extração Dentária
14.
Oper Dent ; 21(5): 185-90, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9484170

RESUMO

This in vitro study evaluated the amount of fluoride released from fluoride-containing materials over a period of 28 days. Six disk samples (2.06 +/- 0.06 cm2) were prepared of each material and divided at random into seven groups: Group 1: Chelon-Fil; Group 2: Chelon-Silver; Group 3: VariGlass; Group 4: Dyract; Group 5: Vitremer; Group 6: Vitremer + Scotchbond Multi-Purpose; Group 7: Fuji II LC. The cements were mixed according to the manufacturers' recommendations, placed in plastic molds, and pressed between two glass plates. Paraffined dental floss was incorporated into the cements during setting to serve as attachments. The materials in Groups 3, 4, and 5 were light cured (Heliolux) in two different positions for 40 seconds each. In Group 6, the adhesive was light cured in two different positions on both sides for 10 seconds each. The samples were stored at 100% relative humidity for 24 hours. Each sample was then suspended in individual plastic tubes containing 5 ml of deionized water and submitted to constant agitation at 25 degrees C. The water was changed every 24 hours. Fluoride release was determined at 1, 2, 3, 4, 5, 7, 14, and 28 days after buffering the solution with equal volume of TISAB. Fluoride release was measured with a fluoride ion-specific electrode (Orion 96-09) and an ionanalyzer (Orion EA 940) previously calibrated with standard solutions containing 0.05 to 5.00 micrograms F/ml. Fluoride release was expressed as ppm in solution and micrograms F/cm2. ANOVA and Student-Newman-Keuls tests were used to evaluate the data. The results revealed that Chelon-Fil released significantly (P < 0.001) more fluoride for the first 7 days than all the other products. This was followed by Fuji II LC, which exhibited significantly more fluoride release than the rest of the materials for the same 7 days. At days 14 and 28, Chelon-Fil, Dyract, and Fuji II LC released similar amounts of fluoride that were significantly greater than the other products. Group 6 (Vitremer + Scotchbond Multi-Purpose) released significantly less fluoride than the other materials at all time intervals. Fluoride release for all products at days 1 and 2 was significantly greater than the rest of the time intervals, except for Chelon-Silver, which released similar amounts of fluoride for days 2, 3, 4, and 5. Although significance for the remaining time intervals varied for all materials, all fluoride release decreased from day 1 to day 28.


Assuntos
Cariostáticos/química , Cimentos Cermet , Compômeros , Resinas Compostas/química , Fluoretos/química , Cimentos de Ionômeros de Vidro/química , Cimentos de Resina/química , Resinas Acrílicas/química , Análise de Variância , Cariostáticos/administração & dosagem , Adesivos Dentinários/química , Estudos de Avaliação como Assunto , Fluoretos/administração & dosagem , Metacrilatos/química , Resinas Sintéticas/química , Silicatos/química , Compostos de Prata/química , Fatores de Tempo
15.
Am J Dent ; 9(2): 54-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9522685

RESUMO

PURPOSE: To compare the accuracy of clinical examination performed with bitewing radiographs or clinical examination using tooth separation to identify carious lesion activity. MATERIALS AND METHODS: 320 surfaces from 40 bitewing radiographs were examined for approximal caries on the maxillary and mandibular primary molars of 20 patients 3-10 years old. The patients were divided into three groups: (1) Absence of the permanent first molar; (2) Partial eruption of the permanent first molar; and (3) Full eruption of the permanent first molar. Two examiners evaluated the radiographs using a megascope, a magnifying glass (x2), and an amplifying image screen. Approximal radiolucencies were identified on 72 surfaces. Following the radiographic examinations, the two examiners performed conventional clinical inspection using a No. 4 dental mirror, a No. 5 dental explorer, and an air-water syringe, with artificial light and relative isolation. The separation method was performed with elastic bands, which were removed after 24 hours, and the clinical examination conducted as in the non-separation group. RESULTS: The correlation between the extension of interproximal radiolucent lesions in primary dentition and their clinical diagnoses following separation of the teeth, was similar to findings on literature evaluating the permanent dentition. On radiographic findings for enamel lesions, white spots predominated both in the inner (100%) and in the outer (94%) half of enamel upon clinical examination with separation of teeth. For radiolucent lesions in dentin, on the other hand, cavities predominated over white spot lesions (84%). In Groups 1 and 2 (young primary), white spots occurred in cases where the radiolucent lesions reached the dentin (15% and 25%), similar to findings for young permanent teeth. Clinical diagnosis performed with the mechanical separation of teeth cannot be considered conclusive for the primary dentition.


Assuntos
Cárie Dentária/diagnóstico , Dente Molar/diagnóstico por imagem , Dente Decíduo/diagnóstico por imagem , Criança , Pré-Escolar , Diagnóstico Bucal , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Mandíbula , Maxila , Radiografia Interproximal
16.
Atherosclerosis ; 117(1): 61-71, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8546756

RESUMO

An antioxidant defense system consisting of enzymes and non-enzymatic compounds prevents oxidative damage of lipoproteins in the plasma. When the activity of this system decreases or the reactive oxygen species (ROS) production increases, an oxidative stress may occur. Since fatty acids and triglyceride-rich emulsions can stimulate leukocytes to produce ROS, it is conceivable that raised plasma triglyceride-rich lipoproteins such as very low density lipoprotein (VLDL) may overload the antioxidant system. To test this hypothesis, we selected 14 patients with combined hyperlipidemia (HLP), in whom low density lipoprotein (LDL) and VLDL levels are elevated, as well as 18 hypercholesterolemic patients (HCH) with increased LDL levels and 19 controls (NL) to examine the trend for an imbalance between the production of oxidative species and the antioxidant defense system as challenged by increased plasma lipids. With this goal, plasma lipoprotein lipid fractions were determined and correlated with the release of ROS by leukocytes monitored by luminol-enhanced chemiluminescence. Plasma beta-carotene, alpha-tocopherol, lycopene and the lipoprotein lipid hydroperoxides were determined by high pressure liquid chromatography with electrochemical detection. HLP had lower plasma superoxide dismutase (SOD) activity (0.04 and 0.11 U/mg protein; P < 0.05) as well as lower concentrations of lycopene (0.1 and 0.2 nmol/mg cholesterol; P < 0.05) and beta-carotene (0.8 and 2.7 nmol/mg cholesterol; P < 0.05) in the plasma, as compared with NL. Moreover, HLP showed the highest ROS production by resting mononuclear leukocytes (MN) among the three study groups. When the results of the subjects of the three groups were taken together, the plasma triglyceride concentration was positively correlated to ROS release by resting polymorphonuclear leukocytes (PMN, r = 0.38, P = 0.04) and MN (r = 0.56, P < 0.005). Moreover, ROS release by resting MN was positively correlated with VLDL (r = 0.47, P = 0.02) and LDL (r = 0.57, P = 0.01) triglycerides. There was also a positive correlation between ROS release by stimulated PMN and VLDL (r = 0.44, P = 0.03) as well as LDL (r = 0.53, P = 0.01) triglycerides. High density lipoprotein (HDL) cholesterol showed a negative correlation with ROS release by resting MN (r = -0.48, P = 0.02) and resting PMN (r = -0.49, P = 0.01). VLDL susceptibility to copper (II) oxidation was not different among the three groups. Regarding LDL, there was an increased oxidizability in HLP group.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Hiperlipidemias/sangue , Leucócitos/metabolismo , Lipoproteínas/sangue , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Triglicerídeos/sangue , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Ferritinas/sangue , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/sangue
17.
Clin Biochem ; 28(4): 435-41, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8521599

RESUMO

OBJECTIVES: Low density lipoprotein (LDL) does not constitute an homogenous fraction and it is known that the heavy LDL subfraction is potentially more atherogenic than the light one. Because concentration of LDL subfractions tend to be different in hyperlipidemias, it was verified whether these subfractions can also differ in sialic acid and neutral sugar content, as well as their resistance to oxidation. DESIGN AND METHODS: Two subfractions of low density lipoprotein (light LDL, density 1.019-1.034 g/mL and heavy LDL, density 1.034-1.063 g/mL) were isolated from the plasma of 17 patients with hypercholesterolemia, 11 with combined hyperlipidemia, 7 with hypertriglyceridemia, and 19 normolipidemic subjects. The content of sialic acids and neutral sugars of apo B was determined, respectively, by the periodate-thiobarbituric acid method and by reaction with phenol. The oxidation of LDL subfractions was determined by exposure to 5 microM copper (II) followed by the measurement of lipid hydroperoxides production by high performance liquid chromatography with electrochemical detection. RESULTS: The study groups did not differ in the neutral sugar content of LDL subfractions. However, compared to normolipidemic subjects, the sialic acid concentration of both LDL subfractions was lower in patients with hypercholesterolemia and hypertriglyceridemia and higher in those with combined hyperlipidemia (p < 0.05). In the hypercholesterolemia and combined hyperlipidemia groups, the lipid hydroperoxide content (microM) of heavy LDL was higher than in normolipidemic subjects (p < 0.05). CONCLUSIONS: The heavy LDL subfraction was more susceptible to oxidation in the patients with combined hyperlipidemia compared to controls and the other hyperlipidemic groups. The effect of sialic acids on heavy LDL oxidizability seems to vary according to the type of hyperlipidemia.


Assuntos
Hiperlipidemias/metabolismo , Lipoproteínas LDL/metabolismo , Ácidos Siálicos/sangue , Adulto , Antioxidantes/farmacologia , Estudos de Casos e Controles , Fracionamento Químico , Feminino , Humanos , Lipoproteínas LDL/química , Lipoproteínas LDL/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Ácido N-Acetilneuramínico , Oligossacarídeos/análise , Oligossacarídeos/química , Oxirredução , Ácidos Siálicos/química , Ácidos Siálicos/farmacologia
18.
Braz Dent J ; 6(1): 41-4, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8688648

RESUMO

The purpose of this study is to evaluate the clinical results obtained with the use of glutaraldehyde in pulpotomies performed on deciduous teeth, in a recall of 24 months. Our results showed a success greater than 90%, similar to other clinical studies.


Assuntos
Exposição da Polpa Dentária/cirurgia , Glutaral/uso terapêutico , Pulpotomia/métodos , Dente Decíduo/cirurgia , Criança , Pré-Escolar , Exposição da Polpa Dentária/terapia , Estudos de Avaliação como Assunto , Seguimentos , Humanos , Resultado do Tratamento
19.
J Clin Pediatr Dent ; 18(3): 187-90, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8054303

RESUMO

One of the alternatives used when the clinical inspection of the fissure is doubtful is the invasive technique. This study used the SEM, to investigate two kinds of burs in doing the invasive technique upon primary molars, as well as to test the suitability of two kinds of sealants (with and without filler particles) to penetrate into such preparations. The points hereby tested revealed to be adequate in obtaining a minimal opening in the enamel, allowing the inspection of the fissure, and at the expense of a slight removal of dubious tissue, permitting a preparation of easy clinical performance. In regard to sealant penetration, no difference was seen between the self-cured sealant and the light-cured sealant.


Assuntos
Preparo da Cavidade Dentária/instrumentação , Fissuras Dentárias/terapia , Restauração Dentária Permanente/métodos , Selantes de Fossas e Fissuras , Pré-Escolar , Preparo da Cavidade Dentária/métodos , Fissuras Dentárias/patologia , Humanos , Microscopia Eletrônica de Varredura , Dente Molar , Dente Decíduo
20.
J Clin Pediatr Dent ; 19(1): 13-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7865416

RESUMO

The purpose of this study was to evaluate with the scanning electron microscope (SEM) the effects of mechanically enlarging the occlusal fissures with a bur in regards to: (1) fissure micromorphology; (2) sealant penetration into fissures; and (3) micromorphology of the fitting surface of sealants. The technique is described as EST, for Enameloplasty Sealant Technique. The conventional sealant technique is referred to as CST. A total of 30 extracted permanent molars were used and divided into four groups: (1) pumice prophylaxis, no sealant; (2) same as Group 1 but with FluoroShield sealant; (3) EST, no sealant; (4) EST followed by FluoroShield. Subgroups were instituted to evaluate the sealant-enamel interface and the sealant fitting surface. The bur used in this, study was specifically designed for this purpose. Some samples were replicated in epoxy resin and all samples were evaluated with the SEM. The results demonstrated that the EST allowed a deeper sealant penetration and a superior sealant adaptation than the CST. An increased surface area for sealant retention was readily evident in all samples treated with the EST.


Assuntos
Preparo da Cavidade Dentária/métodos , Fissuras Dentárias/cirurgia , Selantes de Fossas e Fissuras , Bis-Fenol A-Glicidil Metacrilato , Esmalte Dentário/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Poliuretanos
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