Como determinante principal da redução do índice de cárie desde os anos 80 está a inclusão de fluoretos tanto na água de abastecimento público dos municípios, quanto nos dentifrícios comercializados 2,4 . Como determinante coadjuvante está a odontologia, em sua atuação preventiva e curativa.A cárie dentária sempre se caracterizou como uma preocupação do setor de atenção público odontológico. Mesmo que outros agravos, como doença periodontal e câncer de boca, tenham expressão na população brasileira 3 , os programas de prevenção e educação em saúde bucal se detêm quase que exclusivamente à prevenção da cárie dentária 2 .Uma dessas programações de caráter preventivo-curativo que se destaca na prática odontoló-gica moderna é o Sistema Incremental, elaborado na década de 50 (e já ultrapassado), o qual, até REVISÃO REVIEW

In vitro evaluation of the whitening effect of mouth rinses containing hydrogen peroxide Abstract: The aim of this study was to evaluate the bleaching effect of two mouth rinses containing hydrogen peroxide. Thirty premolars were randomly divided into two groups (n = 15): Listerine Whitening (LW) and Colgate Plax Whitening (PW). The teeth were fixed on a wax plate and with acrylic resin, at a distance of 5 mm between each other, exposing the buccal surfaces. All teeth were stored in artificial saliva for 45 days, being removed twice a day to be immersed for 1 min in each mouthwash, followed by 10-second washing in tap water. The pH of each product was measured. Digital images of each tooth were captured under standardized conditions. These images were cut in areas previously demarcated and analyzed in Adobe Photoshop 7.0 using the CIEL*a*b* color space system. Data were statistically analyzed by a paired t test and an independent samples t test (p < 0.05). The pH values were 5.6 and 3.4 for LW and PW, respectively. Both treatment groups showed a decrease in the b* parameter (p < 0.01), but a decrease of a* was observed only for PW (p < 0.01). While the LW group showed an improvement in lightness (L*) (p = 0.03), the PW group had a decrease in the L* parameter (p = 0.02). Within the limitations of this study, it is possible to conclude that both products caused some degree of whitening; however, extreme care should be taken when using Colgate Plax Whitening, since its decline in luminosity might be due to its lower pH.

Reattachment of fragment is the preferred alternative to restore the fractured teeth, offering several advantages. Partial pulpotomy has demonstrated satisfactory results as a conservative treatment for pulp exposures because of trauma. This study reports a case in which the treatment of a complicated coronal fracture was accomplished by partial pulpotomy and reattachment of a dental fragment obtained from an extracted tooth using composite resin. The results show the feasibility of the conservative pulp therapy and the restorative approach.

This study was carried out to evaluate in situ the influence of microleakage, surface roughness and biofilm control on caries formation around composite resin restorations. During 28 days, 12 volunteers wore palatal devices containing bovine enamel slabs restored with composite resin. Restorations were made without leakage, when the adhesive system was applied, or with leakage, when adhesive system was omitted. Half of the restorations in each group were finished and the remaining were finished and polished. In one side of the palatal device, biofilm was left to accumulate over the restored slabs, and in the other side dental slabs were brushed, to allow biofilm removal. There was an extraoral application of 20% sucrose solution (8x/day) over the enamel slabs. The formation of caries lesions (white spots) was evaluated by visual inspection under stereomicroscopy. Additionally, the dental slabs were sectioned and observed under polarized light microscopy. Data were submitted to Kruskal-Wallis test and Spearman's correlation test at 5% significance level. Polishing and bonding were not significant factors regarding white spot formation (p>0.05). Biofilm control (brushing) was associated with reduction of caries formation close to the restorations (p<0.01). Polarized light microscopy confirmed the visual inspection findings. These results suggest that while microleakage and surface roughness did not influence caries lesion formation, biofilm control may prevent the enamel demineralization.

The aim of the present study was monthly evaluation of fluoride levels in the public water supply in Pelotas, Rio Grande do Sul State, Brazil, and the validity of forming external control groups. Pelotas was divided into 16 geographic regions, including the three public water treatment stations. Water samples were collected from November 1999 to October 2001. Two samples were drawn from each region. Samples were sent to the Fluoride Health Surveillance Laboratory at Universidade do Vale do Itajaí. Fluoride analysis used an electrometric method (Orion 920 A/Electrometer Orion 9609). After 24 months, 764 samples were collected, demonstrating a discontinuity in the fluoride levels. There was an increase in the number of samples with an ideal concentration of fluoride. However, several points with excessive fluoride levels (> 0.9ppmF) also appeared. Based on these results it was concluded that external control is essential for monitoring fluoride levels in the public water supply.

This in vitro study evaluated the effect of different apicoectomy angles, instruments used in root-end preparation, and dental materials used in retrofilling on apical sealing. Root ends were resected at 45 or 90 degrees in 80 single-rooted teeth. For each type of apicoectomy, root-end cavities were prepared with either a round carbide #2 bur or an S12/90D ultrasonic tip. The root-end cavities in each subgroup (apicoectomy + root-end preparation) were filled with silver amalgam without zinc (Am) or with gray mineral trioxide aggregate -Angelus (MTA), and the specimens were immediately immersed in 0.2% rhodamine B for 24 h. Sealing was evaluated based on the dyed crosssectional dentin area. Data were analyzed statistically by the Kruskal-Wallis test at 5% significance level. No group showed complete sealing of root-end areas. The only significant factor affecting microleakage was dental material, with MTA exhibiting less leakage.

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ABSTRACT:The aim of this study was to compare the solvent volatilization rate and evaluate the sealing ability of different one-bottle adhesives that were in constant clinical use -an ethanol/water-based adhesive (Single Bond, 3M/ESPE -SB) and an acetone-based adhesive (Prime & Bond 2.1, Dentsply/Caulk -PB). Nine bottles of each agent were collected from the clinics of a dental school, and new ones were used as controls. The weight of all bottles and of empty bottles was determined using an analytical balance. A drop of each solution was dispensed onto the balance, taking its initial weight (IW) and, after 10 min, its final weight (FW). The IW/FW ratio was used to determine the solvent's volatilization rate. The bottles with the highest evaporation levels (SB Control and PB Control) and with the lowest evaporation levels (SB Test and PB Test) of each agent were applied in Class V restorations with margins in dentin. Specimens were thermocycled and immersed in a 0.5% basic fuchsin solution. Dye penetration was evaluated under magnification and the data were submitted to the Kruskal-Wallis test. Solvent volatilization was faster for the acetone-based adhesive. IW/FW ratios ranged from 1.239 to 1.515 for SB, and from 3.488 to 6.476 for PB. The PB-Control and SB-Control groups exhibited similar microleakage patterns. The highest dye penetration scores were found for the PB-Test group (p < 0.05). Results indicate that the sealing ability can be affected by the repeated opening of acetone-based adhesive bottles. DESCRIPTORS: Dentin-bonding agents; Dental leakage; Solvents; Evaporation. RESUMO:O objetivo deste estudo foi comparar a taxa de volatilização do solvente e a capacidade de selamento de diferentes adesivos de frasco único que estavam em constante uso clínico -um à base de etanol/água (Single Bond, 3M/ESPE) e um à base de acetona (Prime & Bond 2.1, Dentsply/Caulk). Nove frascos de cada agente foram coletados das clínicas da faculdade e outros novos foram utilizados como controle. Os pesos de todos os frascos e de frascos vazios foram determinados em uma balança analítica. Uma gota de cada solução foi dispensada na balança, tomando-se seu peso inicial (PI) e, após 10 min, seu peso final (PF). A razão PI/PF foi utilizada para determinar a taxa de volatilização do solvente. Os frascos com os maiores níveis de evaporação (SB Controle e PB Controle) e com os menores níveis de evaporação (SB Teste e PB Teste) foram aplicados em restaurações Classe V com margens em dentina. Os espécimes foram termociclados e imersos em solução de fucsina básica a 0,5%. A penetração do corante foi avaliada sob magnificação e os dados foram submetidos ao teste de Kruskal-Wallis. A volatilização do solvente foi mais rápida para o adesivo à base de acetona. As razões PI/PF variaram de 1,239 a 1,515 para SB e de 3,488 a 6,476 para PB. PB-Controle e SB-Controle exibiram vedamento similar. Os maiores escores de penetração foram encontrados para o PB-Teste (p < 0,05). Os resultados indicam que a habilidade de selamento pode ser afetada pela r...