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1.
Arch Oral Biol ; 53(8): 744-50, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18472087

RESUMEN

OBJECTIVE: This study aimed to verify whether two demineralisation solutions, with different fluoride concentrations, would produce subsurface lesions in dentine, as assessed by microradiography, with different mineral loss profiles and, subsequently, to determine the dentine permeability of the two altered tissues. METHODS: Forty-five human coronal portions were prepared and randomly divided into two test groups (20 specimens each) with the remaining five as a control group. Each test group was exposed to a demineralisation solution containing either 1 or 5 ppm fluoride for five days. RESULTS: There were highly significant differences between the two test groups for all microradiographic parameters, except for lesion depth. The increase in dentine permeability from baseline to day 5 was statistically significant within each of the two test groups, but not for the control group. CONCLUSION: The differences in the mineral content profile of the two lesions did not influence the magnitude of change in their permeability.


Asunto(s)
Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Permeabilidad de la Dentina/efectos de los fármacos , Fluoruros/administración & dosificación , Remineralización Dental/métodos , Cariostáticos/administración & dosificación , Humanos , Microrradiografía , Desmineralización Dental/prevención & control
2.
J Dent Res ; 66(11): 1644-6, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10872399

RESUMEN

The effect of baseline lesion mineral loss on the remineralization of enamel lesions by a sodium fluoride dentifrice was studied in situ by means of an appliance carrying enamel sections. Artificial lesions of various sizes were created, by means of acidified gelatin, and were then mounted on the appliances of five volunteers. Each brushed twice daily for two min with a 1000 ppm F sodium fluoride dentifrice. Measurements of mineral content were made at baseline and at weekly intervals by microradiographic/microdensitometric techniques. Data from all five volunteers showed a linear increase in remineralization rate with increasing lesion size. Thus, in studies which compare the effects of different remineralizing formulations, care must be taken to ensure that initial lesion sizes are matched, or that the results are expressed as a percentage change in mineral content.


Asunto(s)
Caries Dental/metabolismo , Esmalte Dental/química , Minerales/análisis , Remineralización Dental , Cariostáticos/administración & dosificación , Cariostáticos/uso terapéutico , Densitometría , Caries Dental/patología , Caries Dental/terapia , Esmalte Dental/ultraestructura , Dentífricos/uso terapéutico , Humanos , Análisis de los Mínimos Cuadrados , Modelos Lineales , Microrradiografía , Fluoruro de Sodio/administración & dosificación , Fluoruro de Sodio/uso terapéutico
3.
J Dent Res ; 71(12): 1895-900, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1452890

RESUMEN

Two independent cross-over studies investigated the possibility of enhanced early enamel lesion remineralization with the use of chewing gum. The first study involved a sorbitol-containing chewing gum, and the second, which had an identical protocol, tested a sucrose-containing chewing gum. In each study, 12 volunteers wore in situ appliances on which were mounted enamel sections containing artificial caries lesions. Subjects brushed twice daily for two min with a 1100-ppm-F (NaF) dentifrice (control and test) and in the test phase chewed five sticks of gum per day for 20 min after meals and snacks. Microradiographs of the enamel lesions were made at baseline and at the end of the seven-week experimental period. In the sugar-free gum study, the weighted mean total mineral loss (delta z) difference [(wk7-wk0) x (-1)] was 788 vol.% min. x micron for the gum, corresponding to remineralization of 18.2%, vs. the control value of 526 vol.% min. x micron, 12.1% remineralization (p = 0.07). There were no significant differences for the surface-zone (p = 0.20) and lesion-body (p = 0.28) values. In the sucrose-containing gum study, the delta z difference was 743 vol.% min. x micron for the gum, corresponding to a remineralization of 18.3%, vs. the control value of 438 vol.% min. x micron, 10.8% remineralization (p = 0.08). The surface-zone values were not significantly different (p = 0.55). For the lesion body, however, the sucrose-containing gum value of 6.11 vol.% min. was significantly different (p = 0.01) from that of the control (2.81 vol.% min.).


Asunto(s)
Goma de Mascar , Esmalte Dental/química , Sorbitol/farmacología , Sacarosa/farmacología , Desmineralización Dental/terapia , Remineralización Dental , Adulto , Densitometría , Esmalte Dental/efectos de los fármacos , Esmalte Dental/patología , Humanos , Microrradiografía , Minerales/análisis , Fluoruro de Sodio/administración & dosificación , Fluoruro de Sodio/uso terapéutico , Sorbitol/administración & dosificación , Sacarosa/administración & dosificación , Desmineralización Dental/metabolismo , Desmineralización Dental/patología , Pastas de Dientes
4.
Community Dent Oral Epidemiol ; 15(2): 90-4, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3552397

RESUMEN

Fibre optic transillumination (FOTI) has been employed during the course of a 3-yr clinical dentifrice trial which initially involved 3003 children. At the initial examination, a subgroup of 813 13-yr-olds, and at the following annual visit, 2247 14-yr-olds, were examined using a 150 W lamp and 0.5 mm diameter probe. Routine clinical and radiographic examinations were performed separately. Compared to the clinical scores for anterior teeth, FOTI detected an additional 64% of interproximal lesions at the first visit while, for the larger number of children at the second visit, the increase in lesion detection level using FOTI was 37%. For the posterior teeth the comparable figure at the second examination was 92%. When FOTI data were compared to radiographic data for more than 52,000 posterior interproximal surfaces, FOTI could only detect 17% of radiographic Grade 2 lesions and 48% Grade 3 lesions. Thus any assumption that FOTI diagnoses may be a substitute for bitewing radiography appears premature.


Asunto(s)
Caries Dental/diagnóstico , Tecnología de Fibra Óptica , Transiluminación/métodos , Adolescente , Ensayos Clínicos como Asunto , Caries Dental/diagnóstico por imagen , Método Doble Ciego , Humanos , Radiografía , Distribución Aleatoria
5.
Community Dent Oral Epidemiol ; 16(6): 321-5, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3060308

RESUMEN

A 3-yr clinical trial has been conducted on 3000 12-yr-old children in Lanarkshire, Scotland, with the aim of investigating the effects on oral health of toothpastes containing both sodium monofluorophosphate and zinc citrate, the former being present at fluoride levels of 1000, 1500, and 2500 ppm F. No significant difference in caries increments was found between the group of children using toothpastes incorporating zinc citrate and their counterparts using zinc-free pastes. However, a significant anti-caries dose-response was demonstrated over the SMFP range used. This dose-response was evident for boys and girls and also for the various types of teeth and tooth surfaces.


Asunto(s)
Citratos/administración & dosificación , Caries Dental/prevención & control , Dentífricos , Fluoruros/administración & dosificación , Fosfatos/administración & dosificación , Niño , Ácido Cítrico , Ensayos Clínicos como Asunto , Índice CPO , Caries Dental/patología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Estudios Prospectivos , Distribución Aleatoria , Diente/patología
6.
J Dent ; 30(7-8): 313-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12554112

RESUMEN

OBJECTIVES: To investigate, in vitro, the potential dental effects of diluting juices by measuring their acidity levels and to examine the effect dilution has on the potential erosive properties of the drinks. METHODS: Four commonly available diluting drinks were assessed for both pH and titratable acidity at a variety of dilutions, reflecting the range of concentrations over which such drinks may be consumed. Predetermined dilutions of citric acid and hydrochloric acid, with similar pH values to those of the drinks, were used as positive control acidic solutions. The pH measurements throughout the study were made using a pH electrode connected to an Orion EA940 IonAnalyser. RESULTS: All four drinks demonstrated a high degree of resistance to a rise in pH, indicating high intrinsic buffering capacity. The measured pH changed very little with increasing dilution ratio when compared to the citric and hydrochloric acid controls, even when considered extremely dilute. In contrast, the titratable acidity of each of the drinks reduced proportionally with increasing dilution, thereby reducing considerably its erosive potential. CONCLUSIONS: While dilution had very little effect on the measured pH values, the titratable acidity reduced as the drink became more dilute. Since there appears to be a direct relationship between dilution and titratable acidity, the erosive potential of diluting juices may be reduced substantially by the addition of water. It remains unlikely, however, that the drinks would ever be consumed at a 'safe' level of dilution due to diminished taste and colour.


Asunto(s)
Bebidas/efectos adversos , Bebidas/análisis , Erosión de los Dientes/inducido químicamente , Tampones (Química) , Frutas , Concentración de Iones de Hidrógeno , Soluciones/química , Volumetría
7.
J Dent ; 30(5-6): 243-50, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12450715

RESUMEN

OBJECTIVES: The aim of this study was to estimate the amount of mercury released into both air and saliva from fresh and aged, abraded amalgam discs and then investigate neurotoxic effects of inorganic mercury upon sensory neuronal cultures. METHODS: An air-tight chamber was constructed to allow the combined estimation of mercury species released from amalgam pellets. The level released into air and saliva from both freshly packed and aged-abraded amalgam pellets was assessed. Dorsal root ganglia cultures from male CBA mice were exposed to 1 and 10 microM mercuric chloride concentrations. The effects of this were assessed by means of morphology, adhesion, size and immunocytochemistry. RESULTS: The mercury released into air from dry fresh amalgam was low and less than the recommended industrial exposure limit for mercury. However, covering the discs with saliva reduced air-mercury levels by 46-56% and there was a statistically significant difference in the air-mercury levels recorded (p=0.013-0.048). The mercury released into air from dry abraded amalgam was shown to be above the recommended industrial limit. Coating the abraded amalgam discs with saliva reduced the mercury by 66-72% with the levels recorded being significantly lower (p<0.001). The level of total mercury within the saliva was found to be highly variable. Little change was noted in the neuronal cultures treated with 1 microM mercuric chloride. However, the cultures exposed to high level (10 microM) mercuric chloride showed cells that became rounded and clumped together indicating pathological change. CONCLUSIONS: Amalgam placement appears to present minimal mercury exposure risk. To reduce the amount of mercury released into air, however, amalgam should be polished in a moist atmosphere with high volume aspiration. The neurotoxic effect of mercury appears to be related to concentration, as only in the cultures treated with 10 microM mercuric chloride showed striking qualitative and quantitative cellular changes.


Asunto(s)
Amalgama Dental/química , Ganglios Espinales/efectos de los fármacos , Mercurio/química , Aire , Animales , Adhesión Celular/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Técnicas de Cultivo , Pulido Dental , Difusión , Relación Dosis-Respuesta a Droga , Humanos , Inmunohistoquímica , Masculino , Cloruro de Mercurio/toxicidad , Mercurio/toxicidad , Ratones , Ratones Endogámicos CBA , Neuronas Aferentes/efectos de los fármacos , Neuropéptido Y/análisis , Saliva/química , Estadística como Asunto , Propiedades de Superficie , Volatilización
8.
J Dent ; 31(1): 19-24, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12615016

RESUMEN

OBJECTIVES: To compare, in vitro, the fluoride release from a conventional glass ionomer cement (Ketac-Cem), a resin-modified glass ionomer cement (3M-Multicure) and a polyacid modified composite (Ultra Band-Lok) using a banded tooth model and a disc model with the same mean cement weight. METHODS: Forty pairs of caries-free third molars were collected and divided into two groups, each of 20 teeth. One tooth from each pair was banded with Ketac-Cem and the other with Ultra Band-Lok or 3M-Multicure; the average band size for each cement group was the same. Two coats of nail varnish were painted on each tooth to within 1mm of the band margin. Five discs (4.5mm diameter and 2mm depth) were prepared for each cement, these dimensions having been calculated so that the mean cement weight of the banded tooth model matched that of the disc model for each cement. The fluoride released into 2ml of deionised water, from each banded tooth or disc, was measured at regular intervals over 30 days using an Orion ion-selective electrode connected to an ion analyser. RESULTS: At 30 days, for both banded tooth and disc models, the mean cumulative fluoride release was greatest from 3M-Multicure followed by Ketac-Cem, which in turn released more fluoride than Ultra Band-Lok. These differences were all significant (p<0.05). Despite having the same mean cement weight, the banded tooth model for Ketac-Cem and 3M-Multicure released approximately 3-4 times more cumulative fluoride than the disc model after 30 days (p<001). For Ultra Band-Lok, both models released comparable levels of fluoride (p>0.05). CONCLUSIONS: Cement type, specimen geometry and surface area appear to influence significantly fluoride release characteristics.


Asunto(s)
Cariostáticos/química , Cementos Dentales/química , Fluoruros/química , Soportes Ortodóncicos , Compómeros/química , Cementos de Ionómero Vítreo/química , Humanos , Electrodos de Iones Selectos , Curación por Luz de Adhesivos Dentales/métodos , Óxido de Magnesio/química , Ensayo de Materiales/métodos , Tercer Molar , Cemento de Policarboxilato/química , Cementos de Resina/química , Propiedades de Superficie , Factores de Tiempo , Óxido de Zinc/química
9.
J Dent ; 27(1): 53-61, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9922613

RESUMEN

The aim of this in vitro study was to compare fluoride release from two cement disc models (partially varnished and unvarnished) of three orthodontic bonding materials with fluoride release from the same materials when used to bond an orthodontic bracket onto a tooth surface. A resin-modified glass ionomer cement (Vitremer) and a compomer material (Dyract Ortho) were compared with a conventional resin adhesive (Right-On). Ten discs (3.0 mm diameter and 1.5 mm thick) of each material were manufactured in a silicone mould and ten premolar teeth were bonded with orthodontic brackets using each material. All the premolar teeth were covered with nail varnish up to the bracket periphery and five of the discs for each material were coated with nail varnish on both upper and lower surfaces which halved the surface area. The fluoride released into 2 ml of deionised water, from each tooth or disc, was measured at regular intervals over 60 days. At 60 days, cumulative fluoride release was highest from the unvarnished discs, less for the varnished discs and least from the tooth-bracket model for both test materials. Despite having twice the surface area, the unvarnished disc model released only 1.2 to 1.5 times more fluoride than the varnished disc model. Compared with the tooth-bracket model, the unvarnished discs released 3.0 to 4.5 times more fluoride, whereas the varnished discs released only 2.2 to 3.7 times more fluoride. For the materials tested in this study, halving the surface of the discs did not reduce the cumulative fluoride release by half. The tooth/bracket model with minimal bonding material demonstrated substantial cumulative fluoride release. The pattern of fluoride release was similar for all models tested.


Asunto(s)
Compómeros , Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Fluoruros/química , Cementos de Ionómero Vítreo/química , Metacrilatos/química , Cementos de Resina/química , Silicatos/química , Análisis de Varianza , Diente Premolar , Recubrimiento de la Cavidad Dental , Fluoruros/análisis , Humanos , Técnicas In Vitro , Soportes Ortodóncicos , Proyectos Piloto , Propiedades de Superficie , Factores de Tiempo
10.
J Dent ; 26(5-6): 527-31, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9699447

RESUMEN

OBJECTIVES: Recurrent caries is one of the most common reasons for the replacement of restorations. One method of reducing the frequency of this problem may be by using fluoride-releasing restorative materials. The aim of this in vitro study was to evaluate the progression of artificial lesions around resin-modified glass ionomer (Vitremer) restorations placed in root surfaces. Class V cavities were prepared on the mesial and distal surfaces of 28 human premolar teeth. Artificial carious wall lesions were created in all cavities. The root of each tooth was then hemisected through the middle of the two cavities, before being restored with either the glass ionomer or amalgam, while the opposing cavities on the same root portion were varnished as negative controls. Forty-eight specimens were pH-cycled in remineralising and demineralising solutions for 20 h and 4 h, respectively, each day for 4 weeks, whilst in a smaller control group of eight specimens, the demineralising solution was replaced with deionised water. Mineral changes in the carious lesions were evaluated using contact microradiography. RESULTS: Results showed that varying degrees of subsurface demineralisation and remineralisation were evident, with a laminated appearance in lesions adjacent to the glass ionomer. There was higher remineralisation in the glass ionomer-filled cavities compared with the amalgam-filled cavities. In the water-cycled group, glass ionomer showed an increase in mineral content (p < 0.05), while no changes were observed in the amalgam-filled cavities. CONCLUSIONS: This model has shown that glass ionomer has a greater potential than amalgam for remineralisation of artificially created wall lesions within an acidic environment.


Asunto(s)
Restauración Dental Permanente , Dentina/patología , Cementos de Ionómero Vítreo/química , Cementos de Resina/química , Caries Radicular/prevención & control , Desmineralización Dental/prevención & control , Diente Premolar , Cariostáticos/administración & dosificación , Cariostáticos/química , Cariostáticos/uso terapéutico , Resinas Compuestas/química , Amalgama Dental/química , Preparación de la Cavidad Dental/clasificación , Progresión de la Enfermedad , Estudios de Evaluación como Asunto , Fluoruros/administración & dosificación , Fluoruros/química , Fluoruros/uso terapéutico , Humanos , Concentración de Iones de Hidrógeno , Microrradiografía , Minerales/análisis , Recurrencia , Caries Radicular/patología , Caries Radicular/fisiopatología , Desmineralización Dental/patología , Desmineralización Dental/fisiopatología , Remineralización Dental
11.
J Dent ; 26(5-6): 533-8, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9699448

RESUMEN

OBJECTIVES: The aims of this study were to compare the local and systemic uptake of fluoride released from a compomer material (Dyract Ortho) and a resin-modified glass ionomer cement (Vitremer) with that of a conventional resin adhesive (Right-On) and to compare the cariostatic ability of each of the test materials with that of the resin control. METHODS: Twenty six patients were randomly allocated to have a bracket bonded to a premolar on one side of the arch with one of the test materials and on the opposite side with the control material. Premolars destined for extraction as part of an orthodontic treatment plan were selected for bonding. A non-fluoride toothpaste was used by all participants for 4 weeks prior to bracket bonding and throughout the 4 week trial period. Fluoride release was measured in saliva, plaque and urine samples taken pre-bonding and 4 weeks post-bonding. Enamel demineralisation was assessed by scoring the buccal surface of each extracted tooth using a caries index. RESULTS: Neither Vitremer nor Dyract Ortho altered salivary or urinary fluoride concentration significantly 4 weeks post-bonding but plaque fluoride concentration increased significantly around premolars bonded with Vitremer. The test materials as a combined group were associated with significantly less demineralisation than the control material but there was no significant difference in cariostatic ability detected between either Dyract Ortho or Vitremer when each group was compared separately with the control. CONCLUSIONS: Fluoride released from Dyract Ortho or Vitremer is likely to exert a local and not a systemic effect. In a 4-week clinical study, the cariostatic ability of the fluoride-releasing cements, as a combined group, was superior to that of the non-fluoride releasing control but there was no significant difference in cariostatic ability between the two test materials when each test group was compared separately with the control.


Asunto(s)
Cariostáticos/química , Compómeros , Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Fluoruros/química , Cementos de Ionómero Vítreo/química , Metacrilatos/química , Soportes Ortodóncicos , Cementos de Resina/química , Silicatos/química , Adolescente , Cariostáticos/análisis , Cariostáticos/uso terapéutico , Caries Dental/prevención & control , Esmalte Dental/patología , Placa Dental/química , Recubrimientos Dentinarios/química , Femenino , Fluoruros/análisis , Fluoruros/uso terapéutico , Fluoruros/orina , Humanos , Masculino , Saliva/química , Desmineralización Dental/patología , Desmineralización Dental/prevención & control
12.
J Dent ; 23(3): 145-50, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7782525

RESUMEN

The pulsed Nd: YAG laser is advocated as an alternative means of providing analgesia during routine dental procedures. Since the evidence to support this claim is mainly anecdotal, a clinical trial was carried out using an electric pulp tester (EPT) to measure the extent and duration of any analgesic effect induced by pulsed Nd: YAG laser treatment. A double-blind crossover experiment involving laser and sham treatments was used on 21 subjects. A small (3.6 arbitrary units) but statistically significant increase was observed in the mean responses measured 5 min after laser treatment with 113 mJ pulses at 15 pulses s-1 (pps) for 3 min. The pain thresholds returned to baseline values after 60 min. No statistically significant changes in threshold were found with the sham treatment. The order in which laser and sham treatment was received made no difference to the results.


Asunto(s)
Analgesia/métodos , Anestesia Dental/métodos , Pulpa Dental/efectos de la radiación , Rayos Láser , Umbral del Dolor/efectos de la radiación , Adulto , Análisis de Varianza , Estudios Cruzados , Prueba de la Pulpa Dental , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neodimio , Dimensión del Dolor
13.
J Dent ; 31(1): 25-32, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12615017

RESUMEN

OBJECTIVE: The aims of this in vitro study were firstly to compare fluoride release from a disc model of two orthodontic cements with various surfaces varnished, reducing the surface area by 25, 50 and 75%; secondly, to measure the fluoride release from previously exhausted discs of the same cements following removal of various depths of surface material. METHODS: Forty discs of each cement, Fuji Ortho LC and Ultra Band-Lok, (6mm diameter by 3mm) were divided into two groups of 20 discs each. For each material, the first group was divided further into four groups of five discs, one group acting as control, while the other three groups were varnished reducing the surface area by 25, 50 and 75%, respectively. The second group was exhausted initially over a 60 day pre-experimental period and was subsequently divided into four groups of five discs, one group acting as control. The other three groups had material ground from one of the flat surfaces, to depths of 10, 100 or 1000 microm, to reveal a fresh surface. In both studies, the discs were immersed either daily (up to day 20) or twice weekly (up to day 60) in fresh 2ml aliquots of deionised water. The fluoride concentration in the deionised water was measured at the end of the experimental period. RESULTS: For each cement, the relationship between the cumulative fluoride release and the percentage of the surface covered was clearly non linear at both 5 and 60 days. Fuji Ortho LC proved to release significantly greater amounts of fluoride at both 5 days and 60 days compared with Ultra Band-Lok. The results for Ultra Band-Lok were also significant when compared to the control group, but significantly less fluoride was released when compared with Fuji Ortho LC. When comparing the 25 and 50% covered discs, the amount of fluoride released was not significantly different for both cements. Furthermore, the relationship between fluoride release and depth was clearly non linear for both cements. CONCLUSIONS: For the materials tested in this study, reducing the surface area of the discs did not reduce the cumulative fluoride release in a linear fashion. In addition, the previously exhausted discs began to release fluoride again, but this fell to concentrations similar to the control discs after the initial 5-day period for both cements. This suggests that further traces of previously unreleased fluoride had become available from the subsurface of these cements. The pattern of fluoride release was similar for all models tested.


Asunto(s)
Cariostáticos/química , Cementos Dentales/química , Fluoruros/química , Soportes Ortodóncicos , Resinas Acrílicas/química , Silicatos de Aluminio/química , Compómeros/química , Cementos de Ionómero Vítreo/química , Humanos , Ensayo de Materiales , Cementos de Resina/química , Propiedades de Superficie , Factores de Tiempo , Agua/química
14.
J Dent ; 32(5): 413-21, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15193791

RESUMEN

OBJECTIVE: The aim of this study was to determine whether a dentine bonding agent (DBA) had an effect in reducing fluid filtration under cemented provisional crowns. METHODS: Crown preparations on 34 premolars, randomly allocated to two equal-sized test and control groups, were assessed for dentine permeability by a fluid filtration technique. In the test group, prepared crowns were acid-etched and then treated with a DBA (Prime & Bond NT). In the control group, no such DBA was applied. Provisional crowns were cemented on both groups of teeth using non-eugenol zinc oxide cement. Fluid filtration rates were measured repeatedly after crown preparation, at cementation, 1 h, 1 day, 1 week and 3 weeks following crown cementation for both groups. Filtration rates were also measured after acid-etching and dentine bonding for the test group. RESULTS: There was insufficient evidence to suggest any statistically significant differences either between the two groups or, on average, across the five time points in each group in terms of the relative percentage of fluid filtration. CONCLUSION: The DBA used did not seal dentinal tubules any more than did the smear layer and provisional crowns luted with a non-eugenol ZnO cement.


Asunto(s)
Coronas , Permeabilidad de la Dentina/efectos de los fármacos , Recubrimientos Dentinarios/farmacología , Grabado Ácido Dental , Cementación/métodos , Intervalos de Confianza , Cementos Dentales/uso terapéutico , Dentina/efectos de los fármacos , Dentina/ultraestructura , Líquido de la Dentina/efectos de los fármacos , Filtración/métodos , Estudios de Seguimiento , Humanos , Ácidos Polimetacrílicos/farmacología , Capa de Barro Dentinario , Preparación del Diente , Óxido de Zinc/uso terapéutico
15.
J Dent ; 27(5): 333-9, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10377607

RESUMEN

The present study aims to assess the ability of saliva, both in vitro and in situ, to prevent surface mineral loss from enamel and dentine when exposed to an erosive challenge. Fifteen groups of four varnished thin tooth sections were stored in saliva collected from individuals taking part in the in situ study and a further eight groups, each containing four sections, were stored in deionised water. In vitro, sections were stored in saliva or water for 14 days. In addition, fifteen subjects each wore an appliance with four varnished sections. Appliances with sections were worn for 14 days. All sections were exposed to 25 ml of erosion solution for 5 min twice daily. Microradiography and image analysis of the recovered sections demonstrated significant protection of surface mineral loss from enamel and dentine by saliva in vitro and in situ compared with deionised water (p < 0.05). Significantly less mineral loss (p < 0.05) was observed for enamel and dentine stored in situ compared with storage in saliva in vitro. Generalised linear modelling demonstrated both the subject and protocol had significant effect on mineral loss. A weak positive correlation (r = 0.64) was noted when in situ and in vitro mineral loss from enamel were compared, demonstrating greater reactivity of the in vitro enamel specimens to the erosion challenge. The dentine data did not show any linear correlation. Saliva protected against mineral loss by erosion and, for enamel, in vitro results demonstrated a weak positive correlation with in situ results.


Asunto(s)
Saliva/fisiología , Erosión de los Dientes/prevención & control , Esmalte Dental/química , Dentina/química , Humanos , Agua
16.
J Dent ; 27(6): 455-61, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10399413

RESUMEN

OBJECTIVES: To compare, in vitro, the fluoride release, microbial inhibition and microleakage pattern of a conventional glass ionomer cement (Ketac-Cem) and an acid-modified composite (Ultra Band-Lok) for band cementation. METHODS: Fluoride release was measured from cement discs (3.0 mm diameter and 1.5 mm thick) at regular intervals over 40 days using a potentiometric method. Microbial inhibition was determined for each cement using an agar diffusion test against one of four different strains of Streptococcus mutans. Thirty pairs of banded third molars (15 banded pairs for each cement) were thermocycled and microleakage determined by a dye penetration method. The depth of microleakage was assessed by an index applied by two examiners independently to photographic records taken of the mid-buccal aspect of each tooth. RESULTS: The cumulative and daily fluoride release for days 5, 15 and 40 were significantly greater for Ketac-Cem than for Ultra Band-Lok (all p < 0.05). After the initial set, the anti-microbial activity was significantly greater for Ketac-Cem than for Ultra Band-Lok over the following 24 h period for all four strains of S. mutans (all p < 0.05). There was no significant difference between the two cement groups for microleakage at the cement/enamel interface (p = 0.66) but a borderline significance was detected for microleakage at the cement/band interface (p = 0.051). CONCLUSIONS: The fluoride release and anti-microbial activity of Ketac-Cem were greater than that of Ultra Band-Lok. There was no significant difference in microleakage between the cements at the cement/enamel interface but a borderline difference existed between the cements at the cement/band interface.


Asunto(s)
Recubrimiento Dental Adhesivo/métodos , Filtración Dental , Fluoruros/química , Cementos de Ionómero Vítreo , Óxido de Magnesio , Cemento de Policarboxilato , Óxido de Zinc , Resinas Compuestas/química , Resinas Compuestas/farmacología , Fluoruros/farmacología , Cementos de Ionómero Vítreo/química , Cementos de Ionómero Vítreo/farmacología , Óxido de Magnesio/química , Óxido de Magnesio/farmacología , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Variaciones Dependientes del Observador , Aparatos Ortodóncicos , Cemento de Policarboxilato/química , Cemento de Policarboxilato/farmacología , Estadísticas no Paramétricas , Streptococcus mutans/efectos de los fármacos , Óxido de Zinc/química , Óxido de Zinc/farmacología
17.
Br Dent J ; 167(11): 390-4, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2688726

RESUMEN

Fissure sealant presence was recorded at baseline and annually during a 3-year, double-blind clinical caries trial which involved 3005 children aged 12-13 years at outset. At baseline, initially, 2002 sealants were noted in 431 subjects (14.3%), a figure not dissimilar to that found for Scottish 12-year-olds in the UK National Survey completed in the same year. By the fourth examination, 400 (17.3%) children had 2209 surfaces sealed. After one year, 14%, and at 3 years, 26% of baseline sealants were missing. Overall, at the last examination, 25% of baseline unsealed surfaces were carious compared to 15% of those originally sealed (P less than 0.001), although for molars, the equivalent figures were 49% and 24% (P less than 0.001). Finally, analysis showed that at baseline, as few as 15% of sealants had been placed by general dental practitioners, and this low proportion was maintained throughout the study period. While sealant placement in the Scots' age group was low, nevertheless the prevalence recorded was greater, at least by a factor of three, than has been reported elsewhere in the UK.


Asunto(s)
Selladores de Fosas y Fisuras/uso terapéutico , Niño , Ensayos Clínicos como Asunto , Recubrimiento Dental Adhesivo , Caries Dental/prevención & control , Dentífricos , Método Doble Ciego , Fluoruros/uso terapéutico , Humanos , Diente Molar , Prevalencia , Escocia
18.
Br Dent J ; 169(5): 126-9, 1990 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-2206666

RESUMEN

During the third examination of a 3-year anti-caries dentifrice study, bitewing radiographs were read to detect occlusal, as well as approximal caries lesions in 2623 subjects aged 14-15 years. These analyses showed that 1.4% of 2107 upper molars and 7.2% of 2288 lower molars (P less than 0.001), previously scored as clinically 'sound', were carious at a radiographic Grade '3' score (dentinal involvement), and 0.2% had radiographic pulpal lesions. However, for teeth which had been deemed as having a 'suspicion' of caries clinically, but which a 0.6 mm blunted probe would not enter, 29.1% of lower molars had definite radiographic evidence of dentinal caries as compared to only 7.6% of upper molars (P less than 0.001), and a further 0.5% exhibited pulpal extension. In addition, 23.9% of lower premolars also showed dentinal involvement in this group. Overall, 12.1% of lower molars and 3.1% of upper molars showed definite radiographic evidence of occlusal caries in the absence of a firm clinical indication. Thus, the use of bitewing radiographs would appear to be a most helpful adjunct to clinical caries diagnosis, not only of approximal lesions, but also for the detection of early occlusal caries, in these days of generally available topical fluoride.


Asunto(s)
Caries Dental/epidemiología , Adolescente , Distribución de Chi-Cuadrado , Caries Dental/diagnóstico por imagen , Caries Dental/patología , Humanos , Variaciones Dependientes del Observador , Prevalencia , Radiografía de Mordida Lateral , Escocia/epidemiología
19.
Angle Orthod ; 70(3): 233-40, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10926433

RESUMEN

The study aimed to compare the survival time and cariostatic potential of a compomer to that of a resin adhesive when used to bond stainless steel orthodontic brackets to labial segment teeth only. The effect of the patients' sex, age at the start of treatment and presenting malocclusion on bracket survival time was assessed also. Forty-five consecutive patients who attended for fixed appliance therapy were randomly selected. Four hundred twenty-six brackets were bonded (213 with compomer and 213 with resin adhesive) with a split mouth design; the right or left side allocation of compomer in either arch was alternated. Color transparencies of the maxillary incisors, mandibular incisors, or both, and transparencies of the canines, were taken before treatment. At the debond stage, the transparencies were projected (20x) and assessed by an experienced examiner, who used a caries index. The survival time distributions for brackets bonded with each bonding agent were not significantly different (P = .74, paired Prentice-Wilcoxon test; P = .75, Akritas test), with bracket failure rates of 17% and 20% recorded for compomer and resin adhesive, respectively. Neither the patients' sex (P = .85) nor malocclusion (P = .26) appear to affect significantly bracket survival, but patient age was identified as a useful prognostic indicator of bracket survival (P < .001). On average, there was more decalcification related to brackets bonded with resin adhesive than with compomer (P = .0075). Survival time distributions of brackets bonded with compomer or resin adhesive appear comparable, but decalcification was reduced significantly by bonding with compomer.


Asunto(s)
Compómeros , Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Cementos de Resina , Adolescente , Factores de Edad , Cariostáticos/uso terapéutico , Femenino , Humanos , Modelos Logísticos , Masculino , Maloclusión/clasificación , Metacrilatos , Modelos de Riesgos Proporcionales , Análisis de Regresión , Factores Sexuales , Silicatos , Estadísticas no Paramétricas , Análisis de Supervivencia , Desmineralización Dental/prevención & control
20.
Br Dent J ; 216(1): E2, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24413142

RESUMEN

AIM: To determine the attitudes of patients attending routine appointments at primary care dental clinics and general dental practices towards the possibility of chair-side screening for medical conditions, including diabetes, in the dental setting. METHODS: A brief, anonymous, self-administered questionnaire distributed to adult patients (≥18 years) attending 2 primary care dental clinics and 16 general dental practices in South-West England. RESULTS: One hundred and ninety-seven completed questionnaires were received from patients at primary care dental clinics and 429 from general dental practice patients. Overall, 87% of respondents thought that it was important or very important that dentists screened patients for medical conditions such as diabetes; 79% were very willing to let a dental team member carry out screening. The majority indicated willingness to be screened for various medical conditions during a visit to the dentist, with significantly higher proportions of respondents in the primary care clinics indicating willingness (hypertension: 83% vs 74%; heart disease: 77% vs 66%; diabetes 82% vs 72% [all p <0.02]). Nearly two thirds of primary care clinic respondents and over half of general practice patients indicated that they would be willing to discuss test results with the dental team. Overall, 61% had never knowingly been screened or tested for diabetes; 20% reported that they had been tested within the previous 12 months. CONCLUSION: The majority of respondents supported the concept of medical screening in a dental setting and were willing both to have screening tests and discuss their results with the dental team. Patient acceptance is paramount for successful implementation of such screening programmes.


Asunto(s)
Actitud Frente a la Salud , Servicios de Salud Dental , Diabetes Mellitus/diagnóstico , Adolescente , Adulto , Inglaterra , Humanos , Encuestas y Cuestionarios , Adulto Joven
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