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1.
Int J Paediatr Dent ; 34(3): 246-255, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37864381

RESUMO

BACKGROUND: Few extended studies have explored oscillating-rotating (O-R) toothbrush efficacy in young children. AIM: To compare the efficacy between O-R and manual toothbrushes in reducing plaque and gingivitis after 4 weeks in children. DESIGN: This was a randomized, parallel-group, examiner-blind, clinical trial. In two 50-subject cohorts (3-6 years, primary dentition, parental brushing; 7-10 years, mixed dentition, self-brushing), subjects used Oral-B Kids O-R toothbrush per manufacturer's instructions or Paro Junior manual toothbrush in a customary manner. Plaque and Modified Gingival Index (MGI; primary variable) scores were assessed at baseline and Week 4 for all subjects and within each age group. RESULTS: Both toothbrushes significantly reduced whole mouth and posterior plaque and MGI versus baseline (p < .001). Combined groups: O-R showed greater plaque and MGI reductions versus manual for all measures (p ≤ .003). Three- to 6-year-olds: O-R demonstrated significantly (p < .032) greater whole-mouth (55.7%) and posterior (34.3%) plaque reductions at Week 4 versus manual. Seven- to 10-year-olds: O-R showed significantly (p < .001) greater whole-mouth (94.5%) and posterior (108.4%) plaque reductions and greater (p ≤ .016) whole-mouth (14.1%) and posterior (18.8%) MGI reductions versus manual. There were no adverse events. CONCLUSION: The O-R toothbrush, used per manufacturer's instructions, reduced plaque and gingivitis better than a manual toothbrush used in a customary manner among children.


Assuntos
Placa Dentária , Gengivite , Criança , Humanos , Pré-Escolar , Índice de Placa Dentária , Método Simples-Cego , Desenho de Equipamento , Escovação Dentária , Placa Dentária/prevenção & controle , Gengivite/prevenção & controle
2.
Int J Paediatr Dent ; 31(5): 657-663, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33225464

RESUMO

BACKGROUND: Clinical investigations of electric toothbrushes in young children are limited. AIM: To assess plaque reduction efficacy of an oscillating-rotating electric versus manual toothbrush in a paediatric population in primary and mixed dentitions. DESIGN: In this randomised, single-brushing, 2-treatment, 4-period, replicate-use crossover study, subjects were divided into 2 age groups (3-6 years; 7-9 years) and assigned to a treatment sequence involving an Oral-B Kids electric brush and a manual brush control. Plaque was assessed pre- and post-brushing (Turesky Modified Quigley-Hein Plaque Index). Parents brushed the teeth of their children aged 3-6 years, whereas children aged 7-9 years brushed their own teeth under supervision. Plaque removal scores were analysed for brush differences in each age group separately using an analysis of covariance for crossover design. RESULTS: Forty-one children (n = 20, 3-6 years; n = 21, 7-9 years) completed the study. For the primary dentition in children 3-6 years, the electric brush reduced 32.3% more plaque than the manual brush (P = .005). For the mixed dentition in children 7-9 years, the electric brush reduced 51.9% more plaque than the manual brush (P < .001). CONCLUSIONS: An electric toothbrush reduced significantly more plaque than a manual toothbrush in 2 paediatric age groups.


Assuntos
Placa Dentária , Dentição Mista , Criança , Pré-Escolar , Estudos Cross-Over , Placa Dentária/prevenção & controle , Índice de Placa Dentária , Desenho de Equipamento , Humanos , Método Simples-Cego , Escovação Dentária
3.
Am J Orthod Dentofacial Orthop ; 155(4): 462-472, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30935601

RESUMO

INTRODUCTION: The objective of this 2-arm parallel trial was to determine the plaque removal efficacy (main outcome) and the motivation assessment (secondary outcome) comparing a manual versus an interactive power toothbrush in orthodontic patients. METHODS: Sixty adolescents with fixed orthodontic appliances in both arches were randomized in a 1:1 ratio in this parallel, randomized, examiner-blind controlled clinical trial. Eligibility criteria included at least 16 natural teeth, 1-6 "focus care areas," plaque score of ≥1.75, no severe caries, gingivitis and periodontitis, no dental prophylaxis, no smoking, no antibiotics, and no chlorhexidine mouth rinse. Subjects were to brush unsupervised with either an interactive power toothbrush (Oral-B Professional Care 6000, D36/EB20) with Bluetooth technology or a regular manual toothbrush (Oral-B Indicator 35 soft). Focus care areas were each brushed for 10 additional seconds. Plaque removal was assessed with the use of the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI) to determine change from baseline at 2 and 6 weeks. Supervised brushing at screening and post-treatment visits recorded actual brushing times. Subject-reported motivational aspects were recorded at screening and week 6. RESULTS: Fifty-nine subjects aged 13-17 years completed the study. The interactive power toothbrush provided significantly (P <0.001) greater plaque reduction versus the manual toothbrush at 2 and 6 weeks according to the whole-mouth TMQHPI. The treatment difference in adjusted mean plaque change from baseline was 0.777 (95% CI 0.614-0.940) at week 2 and 0.834 (0.686-0.981) at week 6. Mean reductions in the number of focus care areas were also significantly greater (P <0.001) in the power brush group at weeks 2 and 6. Brushing times increased significantly at weeks 2 and 6 (P ≤0.013) versus baseline in the interactive power brush group only. Subject-reported motivation was significantly increased in the interactive power brush group at week 6 versus screening (P ≤0.005). CONCLUSIONS: An interactive power toothbrush generated increased brushing times and significantly greater plaque removal versus a manual brush.


Assuntos
Placa Dentária/prevenção & controle , Motivação , Aparelhos Ortodônticos Fixos , Escovação Dentária/instrumentação , Adolescente , Índice de Placa Dentária , Feminino , Humanos , Masculino , Método Simples-Cego , Escovação Dentária/psicologia , Escovação Dentária/estatística & dados numéricos
4.
BMC Oral Health ; 18(1): 130, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30075780

RESUMO

BACKGROUND: Many adolescents have poor plaque control and sub-optimal toothbrushing behavior. Therefore, we compared the efficacy of an interactive power toothbrush (IPT) to a manual toothbrush (MT) for reducing dental plaque and improving toothbrushing compliance. METHODS: In this randomized, parallel single-blind clinical study, adolescents brushed twice daily with either a MT (Oral-B® Indicator soft manual toothbrush) or an IPT (Oral-B® ProfessionalCare 6000 with Bluetooth). Subjects brushed for 2 min, plus an additional 10 s for each 'Focus Care Area'. At screening and Week 2, afternoon pre-brushing plaque was assessed via the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI), and supervised brushing duration was measured. RESULTS: Sixty subjects were randomized; 98% completed. At Week 2, the mean reduction in whole mouth plaque relative to baseline was 34% (p < 0.001) for the IPT versus 1.7% (p = 0.231) for the MT. For Focus Care Areas, the IPT yielded a 38.1% mean TMQHPI reduction (p < 0.001) versus 6.2% for the MT (p < 0.001). Mean brushing time versus baseline increased 34 s in the IPT group (p < 0.001) while remaining flat in the MT group (p = 1.0). CONCLUSIONS: Over 2 weeks, adolescents using an IPT experienced superior plaque reduction and increased overall brushing time versus those using a MT. TRIAL REGISTRATION: This trial was retrospectively registered ( ISRCTN10112852 ) on the 18th, June 2018.


Assuntos
Placa Dentária/prevenção & controle , Cooperação do Paciente , Escovação Dentária/instrumentação , Adolescente , Índice de Placa Dentária , Feminino , Humanos , Masculino , Cooperação do Paciente/psicologia , Cooperação do Paciente/estatística & dados numéricos , Método Simples-Cego , Escovação Dentária/métodos , Escovação Dentária/psicologia , Escovação Dentária/estatística & dados numéricos
5.
J Clin Dent ; 29(1): 27-32, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29758154

RESUMO

OBJECTIVES: To evaluate and compare the efficacy of a marketed oscillating-rotating electric rechargeable toothbrush to a marketed sonic toothbrush in the reduction of gingivitis and plaque over an 8-week period. METHODS: This was a randomized, examiner-blind, parallel group, eight-week study. Subjects with presence of mild-to-moderate plaque and gingivitis received an oral examination and were evaluated for baseline gingivitis (Modified Gingival Index; MGI), gingival bleeding (Gingival Bleeding Index; GBI), and plaque (Rustogi Modified Navy Plaque Index). Qualified subjects were randomly assigned to an entry-level oscillating-rotating electric rechargeable brush handle (Oral-B® PRO 1000, D16U) with a round brush head with angled bristles (Oral-B® CrossAction, EB50) or a premium sonic brush (Philips Sonicare® Diamond Clean Toothbrush with AdaptiveClean brush head). One hundred and fifty subjects were instructed to brush twice daily with their assigned brush and a fluoride dentifrice for eight weeks before returning for an oral examination and gingivitis and plaque evaluations. The same methods were used at baseline and Week 8 for all evaluations. RESULTS: One hundred and forty-eight subjects completed the study, 74 in each group. After eight weeks of use, both brushes reduced MGI, GBI, total number of bleeding sites, whole mouth plaque, gingival margin plaque, and proximal plaque (p < 0.001 for each). The oscillating-rotating brush provided statistically significantly greater reductions than the sonic brush for all gingivitis measures, with a 34.8%, 48.4%, and 42.6% greater reduction for MGI, GBI, and number of bleeding sites, respectively, after eight weeks of use (p < 0.001 for each). Significantly greater whole mouth (26.2%) and proximal (38.5%) plaque reductions were also demonstrated at Week 8 for the oscillating-rotating brush versus the sonic brush (p < 0.001). CONCLUSIONS: The entry-level oscillating-rotating brush performed better than the premium sonic brush in the reduction of plaque and gingivitis in this eight-week randomized and examiner-blind study.


Assuntos
Placa Dentária , Gengivite , Escovação Dentária , Placa Dentária/terapia , Índice de Placa Dentária , Desenho de Equipamento , Gengivite/terapia , Humanos , Índice Periodontal , Método Simples-Cego , Escovação Dentária/instrumentação
6.
Am J Dent ; 29(1): 20-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27093772

RESUMO

PURPOSE: To evaluate the dental stain removal efficacy of two commercially-available manual toothbrushes. METHODS: This was a randomized, examiner-blind, parallel-group, two treatment clinical trial of 2 weeks duration. Subjects qualifying for the study had a mean Modified Lobene Stain Index of ≥ 1.5 on at least two anterior teeth. Subjects were randomly allocated to one of two groups, receiving a test manual toothbrush (Oral-B 3D White Radiant) or a positive control (PC) manual brush to be used for 1 minute, twice daily for 2 weeks with a standard, anti-cavity fluoride dentifrice. Subjects were given written and verbal instructions, and the first use was supervised at the baseline visit. Stain was measured at baseline and after 2 weeks of product use. Stain measurements were conducted using the Modified Lobene Stain Index (MLSI) and the Interproximal Modified Lobene Stain Index (IMLSI). RESULTS: Use of the two manual brushes resulted in statistically significant reductions of surface stain relative to baseline after 2 weeks of use. The mean MLSI composite stain reductions versus baseline were 1.37 for White Radiant and 0.87 for PC (P < 0.001 for both). Using the IMLSI, the mean stain reductions for composite, gingival and interproximal regions were 1.68, 1.20 and 1.68 for White Radiant (P < 0.001) and 1.25, 0.97 and 1.43 for PC (P ≤ 0.002). ANCOVA yielded statistically significant between group differences, with greater composite stain removal observed for White Radiant using both indices (P ≤ 0.025).


Assuntos
Descoloração de Dente/terapia , Escovação Dentária/instrumentação , Adulto , Idoso , Cariostáticos/uso terapêutico , Café , Dentifrícios/uso terapêutico , Desenho de Equipamento , Feminino , Fluoretos/uso terapêutico , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Fumar , Chá , Descoloração de Dente/classificação , Resultado do Tratamento , Adulto Jovem
7.
J Clin Dent ; 26(3): 80-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26665291

RESUMO

OBJECTIVE: To evaluate and compare the efficacy of an oscillating-rotating (O-R) power toothbrush with a brush head utilizing angled bristles to a marketed sonic toothbrush in the reduction of plaque and gingivitis over an eight-week period. METHODS: This study used a randomized, examiner-blind, single-center, two-treatment, parallel group, eight-week design. Subjects with mild-to-moderate plaque and gingivitis were evaluated for baseline whole mouth, gingival margin, and approximal plaque, gingivitis, and gingival bleeding. Clinical assessments were performed using the Modified Gingival Index, Gingival Bleeding Index, and the Rustogi Modified Navy Plaque Index. Subjects received either the O-R brush (Oral-B Professional Care 1000 [D16u] with Oral-B CrossAction brush head [EB50]) or the sonic brush (Sonicare DiamondClean with the standard DiamondClean brush head). Subjects brushed twice daily for two minutes per brushing with the assigned brush and a standard fluoride dentifrice for eight weeks before returning for plaque and gingivitis evaluations using the same methods. Prior to baseline and Week 8 measurements, participants abstained from oral hygiene for 12 hours. RESULTS: One hundred and forty-eight subjects completed the study; 75 in the O-R group and 73 in the sonic group. Both brushes demonstrated statistically significant reductions in plaque and gingivitis over the eight-week study period (p < 0.00 1). The O-R brush was statistically significantly more effective in reducing plaque and gingivitis than the sonic brush. Whole mouth, gingival margin, and approximal plaque reductions were 27.7%, 46.8%, and 29.3% greater, respectively, compared with the sonic brush, while the reductions in gingivitis, gingival bleeding, and number of bleeding sites were 34.6%, 36.4%, and 36.1% greater, respectively, for the O-R brush than for the sonic brush (p < 0.001 for all six measures). No adverse events were observed for either brush. CONCLUSION: The plaque and gingivitis reductions for the O-R power brush incorporating the angled-bristled brush head were significantly greater than for the sonic power brush.


Assuntos
Placa Dentária/prevenção & controle , Gengivite/prevenção & controle , Escovação Dentária/instrumentação , Adolescente , Adulto , Idoso , Cariostáticos/uso terapêutico , Índice de Placa Dentária , Dentifrícios/uso terapêutico , Desenho de Equipamento , Feminino , Fluoretos/uso terapêutico , Seguimentos , Hemorragia Gengival/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Método Simples-Cego , Propriedades de Superfície , Resultado do Tratamento , Adulto Jovem
8.
Clin Oral Investig ; 16(4): 1007-14, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21750917

RESUMO

The aim of this study was to evaluate the remineralization potential of three silica-containing NaF dentifrice systems in an intraoral model. Subjects (N = 30) in this randomized, three-phase, 28-day, crossover study served as their own control. Each participant wore a customized orthodontic appliance attached to a mandibular molar and contained one tooth block with caries-like lesion. For each phase, participants engaged in twice-daily brushing for 2 min with one of the following dentifrices: 500 ppm F, 500 ppm F plus functionalized ß-tricalcium phosphate (fTCP), and a clinically proven 1,100 ppm F. After each phase, appliances were removed, and specimens were analyzed using surface microhardness (SMH), transverse microradiography (TMR), and cross-sectional microhardness (CSMH). Statistically significant (p < 0.05) remineralization of white-spot lesions relative to baseline occurred for each dentifrice as determined with SMH and TMR. No significant differences (p > 0.05) in SMH were found among the three groups, but trending revealed the 500 ppm F plus fTCP produced 26% and 27% greater SMH recovery relative to 500 and 1,100 ppm F, respectively. Similarly, no significant differences (p > 0.05) in TMR were found among the groups. However, the 500 ppm F plus fTCP dentifrice produced 10% and 38% greater mineral recovery relative to 500 and 1,100 ppm F, respectively, while reducing the lesion depth 30% and 52%, respectively. Significant differences (p < 0.05) in CSMH existed among the three dentifice groups at different enamel depths, but statistical differences (p < 0.05) in relative lesion size were only found between 500 ppm F plus fTCP and 500 ppm F. The combination of fTCP and fluoride in a single-compartment, water-based dentifrice can cooperate with fluoride to produce significant remineralization. These results suggest that the combination of 500 ppm F with fTCP may provide comparable anticaries benefits relative to a 1,100 ppm F dentifrice.


Assuntos
Cariostáticos/uso terapêutico , Cárie Dentária/terapia , Esmalte Dentário/efeitos dos fármacos , Dentifrícios/uso terapêutico , Fluoreto de Sódio/uso terapêutico , Remineralização Dentária/métodos , Adolescente , Adulto , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/uso terapêutico , Fosfatos de Cálcio/administração & dosagem , Fosfatos de Cálcio/uso terapêutico , Cariostáticos/administração & dosagem , Estudos Cross-Over , Cárie Dentária/patologia , Esmalte Dentário/patologia , Feminino , Dureza , Humanos , Masculino , Microrradiografia , Pessoa de Meia-Idade , Minerais/análise , Ácido Silícico/administração & dosagem , Ácido Silícico/uso terapêutico , Fluoreto de Sódio/administração & dosagem , Escovação Dentária/métodos , Cremes Dentais/administração & dosagem , Cremes Dentais/uso terapêutico , Adulto Jovem
9.
Acta Odontol Latinoam ; 25(1): 115-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22928391

RESUMO

The aim of this study was to evaluate the polymerization stress and degree of conversion of a composite submitted to different photoactivation protocols. The composite Filtek Z350 was placed in the central perforation of a photoelastic disc and polymerized using a LED-based curing unit (BluePhase II--Ivoclar Vivadent) with energy density of 12, 24 or 36 J/cm2 using the following photopolymerization protocols: continuous high intensity (HI: 1200 mW/cm2 during 10, 20 or 30s), continuous low intensity (LI: 650 mW/cmz during 18, 36 or 54s) and soft-start (SS: 150 mW/cm2 during 5 s + 1200 mW/cm2 during 9, 19 or 29s) (n = 5). Photoelastic analysis was used to evaluate polymerization shrinkage stress and FTIR was performed to determine the degree of conversion of the composite. ANOVA 3-way procedure was used to determine the significance of the main effects and their interactions followed by two-way ANOVA for each time was performed (p < 0.05). Shrinkage stress increased with higher values of energy. No statistically significant differences on polymerization shrinkage stress were found between high and low intensity activation modes. Soft-start method generated stresses that were statistically lower than continuous modes except when 12 J/cm2 was applied. Similar degree of conversion was observed for photoactivation modes used, except for soft-start mode with 12, 24 and 36J/cm2 that showed lowest levels of conversion. Energy density and activation mode influenced polymerization shrinkage stress, but no benefit on degree of conversion was observed.


Assuntos
Resinas Compostas , Análise do Estresse Dentário , Luz , Teste de Materiais , Polimerização
10.
Oral Health Prev Dent ; 19(1): 137-147, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33615769

RESUMO

PURPOSE: To compare clinical outcomes and oral fluid biomarkers in gingivitis subjects using an electric toothbrush/irrigator combination (test) or a manual toothbrush alone (control) over 8 weeks. MATERIALS AND METHODS: Subjects were randomly assigned to two groups of n = 30. In both groups, toothbrushing was performed twice daily at home and no additional interdental cleaning aids were allowed. Plaque Index (PLI), Gingival Index (GI), whole saliva (WS), and gingival crevicular fluid (GCF) samples were collected at weeks 2, 4, and 8. RESULTS: Subjects' mean age was 23 years and 52% were female. Overall baseline means were 1.31 for PLI, 1.07 for GI, and 34.9 for number of bleeding sites. At every follow-up visit, both groups differed statistically significantly (p < 0.001) from baseline for all clinical parameters. The test group demonstrated statistically significantly (p < 0.001) greater reductions in GI vs the control group by 18% at week 2, 17% at week 4 and 24% at week 8. The test group also demonstrated statistically significantly (p < 0.002) greater reductions in the number of bleeding sites vs the control group by 33% at week 2, 34% at week 4 and 43% at week 8. Between-group comparisons for both WS and GCF revealed numerical trends for decreased levels of interleukin (IL)-1ß in GCF after 4 and 8 weeks, but these were not statistically significant. CONCLUSION: In subjects using the electric toothbrush/irrigator combination, increased clinical improvements may be found accompanied by similarly improved trends for oral fluid biomarkers such as IL-1ß.


Assuntos
Placa Dentária , Gengivite , Adulto , Biomarcadores , Índice de Placa Dentária , Desenho de Equipamento , Feminino , Gengivite/terapia , Humanos , Masculino , Método Simples-Cego , Escovação Dentária , Adulto Jovem
11.
Arch Oral Biol ; 57(5): 525-30, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22041022

RESUMO

OBJECTIVE: The purpose of this pilot study was to evaluate the remineralisation of eroded enamel by NaF rinses in an intra-oral model. METHODS: Serving as their own control, subjects (N=80) participated in a randomised, four-leg (20 subjects/leg), 28-day, parallel design study. In each leg, each participant wore a customised orthodontic bracket attached to a mandibular molar that contained one tooth block having an initial erosive lesion (0.3% citric acid, pH 3.75, 2 h). Within the 28-day period, participants engaged in twice-daily brushing for 1 min with a fluoride-free dentifrice followed by 1-min rinsing with one of the following aqueous rinses: fluoride-free (0 ppm F), 225 ppm F, 225 ppm F plus functionalised ß-tricalcium phosphate (fTCP), and 450 ppm F. Following intra-oral exposure, appliances were removed and specimens were analysed using surface microhardness (SMH) and transverse microradiography (TMR). RESULTS: Statistically significant (p<0.05) remineralisation, as determined by SMH and TMR, of the eroded enamel relative to baseline occurred for each fluoride system. No significant differences in SMH were observed amongst the fluoride groups (p>0.05), however, 225 ppm plus fTCP produced 27% and 7% SMH indent length reduction relative to 225 ppm F and 450 ppm F, respectively. No significant differences in TMR were observed amongst the fluoride groups (p>0.05), however, 225 ppm F plus fTCP and 450 ppm F produced significant (p<0.05) mineral gains relative to the fluoride-free control, whilst 225 ppm F did not (p>0.05). Relative to the 225 ppm F group, the 450 ppm F and 225 ppm F plus fTCP groups produced 65% and 61% greater mineral change, respectively. CONCLUSIONS: These pilot results demonstrate this model is sensitive to fluoride and that addition of fTCP to an aqueous rinse containing 225 ppm F may provide significant remineralisation benefits. Therefore, the combination of relatively low levels of fluoride and fTCP might be an effective alternative to a high fluoride treatment for anti-erosion benefits.


Assuntos
Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Antissépticos Bucais/farmacologia , Fluoreto de Sódio/farmacologia , Erosão Dentária/tratamento farmacológico , Remineralização Dentária/métodos , Adolescente , Adulto , Análise de Variância , Esmalte Dentário/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aparelhos Ortodônticos , Projetos Piloto , Radiografia , Propriedades de Superfície , Erosão Dentária/diagnóstico por imagem , Escovação Dentária , Resultado do Tratamento
12.
Pediatr Dent ; 34(7): e197-201, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23265155

RESUMO

PURPOSE: The purpose of this study was to evaluate the effect of whole bovine milk on Streptococcus mutans biofilms and on demineralization of enamel and root dentin. METHODS: S mutans UA159 biofilms were cultured on enamel and dentin bovine slabs of known surface hardness (SH) and exposed (8x/day) to 10% sucrose (positive control), whole bovine milk, and 4.5% lactose. Biofilm acidogenicity was estimated by medium pH (2x/day). After 4 days for dentin and 5 days for enamel, biofilms were collected to obtain biomass, viable bacteria, total protein, and intra- and extracellular polysaccharides. Final SH was measured on the slabs. Demineralization was calculated as percentage of SH loss (%SHL). Differences were determined by analysis of variance and Tukey's test (P<.05). RESULTS: Biofilms formed on both substrates under 10% sucrose showed higher acidogenicity, biomass, protein concentration, insoluble polysaccharides, and %SHL than those treated with milk or lactose (P<.05), which did not differ in any parameter (P>.05). Higher bacterial counts were obtained from biofilms treated with milk on enamel, but not on dentin. Dentin was significantly more demineralized by milk than enamel (P<.05). CONCLUSIONS: Although bovine milk appears to be less cariogenic than sucrose, this dairy product should not be considered caries-safe.


Assuntos
Biofilmes , Cariogênicos/efeitos adversos , Leite/efeitos adversos , Streptococcus mutans , Desmineralização do Dente/etiologia , Análise de Variância , Animais , Bovinos , Contagem de Colônia Microbiana , Esmalte Dentário/microbiologia , Esmalte Dentário/patologia , Dentina/microbiologia , Dentina/patologia , Dureza , Concentração de Íons de Hidrogênio , Lactose/efeitos adversos , Estatísticas não Paramétricas , Sacarose/efeitos adversos
13.
Acta odontol. latinoam ; 25(1): 114-121, 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-949676

RESUMO

The aim of this study was to evaluate the polymerization stress and degree of conversion of a composite submitted to different photoactivation protocols. The composite Filtek Z350 was placed in the central perforation of a photoelastic disc and polymerized using a LED-based curing unit (BluePhase II - IvoclarVivadent) with energy density of 12, 24 or 36 J/cm² using the following photopolymerization protocols: continuous high intensity (HI: 1200 mW/cm² during 10, 20 or 30s), continuous low intensity (LI: 650 mW/cm² during 18, 36 or 54s) and soft-start (SS: 150 mW/cm² during 5 s + 1200 mW/cm² during 9, 19 or 29s) (n=5). Photoelastic analysis was used to evaluate polymerization shrinkage stress and FTIR was performed to determine the degree of conversion of the composite. ANOVA 3-way procedure was used to determine the significance of the main effects and their interactions followed by two-way ANOVA for each time was performed (p<0.05). Shrinkage stress increased with higher values of energy. No statistically significant differences on polymerization shrinkage stress were found between high and low intensity activation modes. Softstart method generated stresses that were statistically lower than continuous modes except when 12 J/cm² was applied. Similar degree of conversion was observed for photoactivation modes used, except for soft-start mode with 12, 24 and 36 J/cm² that showed lowest levels of conversion. Energy density and activation mode influenced polymerization shrinkage stress, but no benefit on degree of conversion was observed.


O objetivo neste estudo foi avaliar a tensão de contração de polimerização e o grau de conversão de uma resina composta submetida a vários protocolos de fotoativação. O compósito Filtek Z350 foi inserido na perfuração central de um disco de resina fotoelástica e polimerizado usando uma unidade de fotoativação LED (BluePhase II - IvoclarVivadent) com as doses de energia de 12, 24 or 36 J/cm² usando os seguintes protocolos de polimerização: contínuo de alta intensidade (HI: 1200 mW/cm² durante 10, 20 ou 30s), contínuo de baixa intensidade (LI: 650 mW/cm² durante 18, 36 ou54s) e "soft-start" (SS: 150 mW/cm² durante 5 s + 1200 mW/cm² durante 9, 19 ou 29s) (n=5). Análise fotoelástica e Espectroscopia Infravermelha Transformada de Fourier (FTIR) foram usados para avaliar a tensão de contração de polimerização e grau de conversão do compósito respectivamente. O teste ANOVA três fatores foi usado para determinar os principais efeitos e interações das variáveis e seguidamente, ANOVA 2 fatores para ver a diferença entre os grupos (p<0.05). A tensão de contração aumentou com valores maiores de energia. Não foram observadas diferenças estatisticamente significantes para a tensão de contração entre os modos de alta e baixa intensidade. O modo "soft-start" gerou menor tensão que os modos contínuos, exceto quando 12 J/cm² foi aplicado. Similar grau de conversão foi observado para os modos de fotoativação usados, com exceção do modo "soft-start" com 12, 24 e 36 J/cm² que mostraram níveis menores de conversão. A dose de energia e modo de ativação influenciam a tensão de contração de polimerização, porém nenhum benefício no grau de conversão foi observado.


Assuntos
Resinas Compostas , Teste de Materiais , Análise do Estresse Dentário , Polimerização , Luz
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