The impact on the quality of life caused by the early loss of primary molars.

INTRODUCTION: Evidence regarding the impact of early loss of primary molars (ELPM) on Oral Health-Related Quality of Life (OHRQoL) is lacking. The aim of the present study was evaluating the impact of ELPM on OHRQoL of Brazilian schoolchildren aged 6-10 years. METHODS: This observational prospective cohort study was conducted with 163 schoolchildren, assigned in the primary tooth loss group (PTLG), in which all tooth loss was caused by carious lesions, and in a control group without tooth loss (CG). Two calibrated examiners conducted the clinical oral assessments to determine caries experience and tooth loss. OHRQoL was assessed using the Child Perception Questionnaire 8-10 years (CPQ8-10) instrument administered at baseline and at 10-12 months of follow-up. RESULTS: Children in PTLG exhibited significantly more negative impact on OHRQoL at baseline (p < 0.01) than CG, and also after the follow-up period (p < 0.01). It was also possible to observe a significant reduction in the negative impact on OHRQoL in both CG and PTLG in the longitudinal analysis (p < 0.01). Nevertheless, there was an even more substantial reduction in the negative impact on OHRQoL in children in PTLG. CONCLUSIONS: This study provides evidence that early tooth loss is associated with negative impact on OHRQoL. Moreover, it indicates that access to dental treatment can have a positive impact on the OHRQoL of children with dental caries and ELPM.

Reduction of cardiovascular risk in patients with metabolic syndrome in a community health center after a pharmaceutical care program of pharmacotherapy follow-up

The objective of this study was to determine the impact of a pharmaceutical care (PC) program in a sample of public outpatients with metabolic syndrome (MS) who were being treated in Brazil's health system; the patients were randomized into PC or standard care. The pharmacotherapy follow-up (PF) was performed in a total of 120 patients with type 2 diabetes for 6 months. Adherence to treatment (measured with the Morisky test), negative outcomes associated with medication (NOM) and anthropometric and biochemical parameters were measured before and after PF. The Framingham scoring method was used to estimate changes in 10-year coronary heart disease risk scores in all patients. Ninety-six of 120 patients had characteristics of MS and were randomized into two groups (G): the control group (CG: 36) and the intervention group (IG: 38). Among the MS patients, 100% were taking a glucose-lowering drug; many were also taking anti-hypertensive drugs (CG: 72%; IG: 73%), and some patients were also taking hypolipemic drugs (CG: 12.0%; IG: 14.7%). Only 20.7% of the IG patients were considered adherent to their prescribed drugs. In the CG, an increase of coronary heart disease (CHD) risk (22±2 to 26±3; p<0.05) was observed, while in the IG, there was a reduction in CHD risk (22±2 to 14±2%; p<0.01). The PC program administered to patients with MS monitored through the primary healthcare services of the Brazilian public health system improved patient health, resulting in clinical improvements and a decrease in cardiovascular risk in IG patients over a period of ten years.

O objetivo deste estudo foi o de determinar o impacto de um Programa de atenção Farmacêutica (AF) em uma amostra de pacientes ambulatoriais de Sistema Público de Saúde do Brasil portadores de Síndrome Metabólica, randomizados em AF ou atenção à saúde usual. Realizou-se o seguimento farmacoterapêutico com 120 pacientes com diabetes tipo 2 durante seis meses. Avaliou-se o nível de aderência ao tratamento (teste Morisky), resultados clínicos negativos associados a medicamentos (RNM), parâmetros bioquímicos e antropométricos, antes e após o seguimento. O método de Framingham foi usado para calcular as variações no risco de doenças coronarianas em 10 anos em todos os pacientes. Dos 120 pacientes, 96 tiveram características de SM e foram então randomizados em dois grupos (G): Controle (GC: 36) e Intervenção (GI: 38). Entre os pacientes com SM, 100% faziam uso de medicamentos para diminuir a glicose, anti-hipertensivos (GC: 72%; GI: 73%) e hipoglicemiantes (GC: 12.0%; GI: 14.7%). Apenas 20,7% do GI foram considerados aderentes aos fármacos prescritos. No GC foi observado aumento do risco de Doença Arterial Coronariana (DAC) (22±2 para 26±3; p<0,05), enquanto no GI foi observado redução (22±2 para 14±2%; p<0,01). O Programa de AF para pacientes com SM monitorados na atenção primária do Sistema de Saúde Pública brasileiro melhora o funcionamento do serviço resultando na melhoria clínica dos pacientes com redução do risco de doença cardiovascular em um período de dez anos.

Effects of light-curing time on the cytotoxicity of a restorative composite resin on odontoblast-like cells.

UNLABELLED: This in vitro study evaluated the cytotoxicity of an experimental restorative composite resin subjected to different light-curing regimens. METHODS: Forty round-shaped specimens were prepared and randomly assigned to four experimental groups (n=10), as follows: in Group 1, no light-curing; in Groups 2, 3 and 4, the composite resin specimens were light-cured for 20, 40 or 60 s, respectively. In Group 5, filter paper discs soaked in 5 µL PBS were used as negative controls. The resin specimens and paper discs were placed in wells of 24-well plates in which the odontoblast-like cells MDPC-23 (30,000 cells/cm²) were plated and incubated in a humidified incubator with 5% CO2 and 95% air at 37ºC for 72 h. The cytotoxicity was evaluated by the cell metabolism (MTT assay) and cell morphology (SEM). The data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (p<0.05). RESULTS: In G1, cell metabolism decreased by 86.2%, indicating a severe cytotoxicity of the non-light-cured composite resin. On the other hand, cell metabolism decreased by only 13.3% and 13.5% in G2 and G3, respectively. No cytotoxic effects were observed in G4 and G5. In G1, only a few round-shaped cells with short processes on their cytoplasmic membrane were observed. In the other experimental groups as well as in control group, a number of spindle-shaped cells with long cytoplasmic processes were found. CONCLUSION: Regardless of the photoactivation time used in the present investigation, the experimental composite resin presented mild to no toxic effects to the odontoblast-like MDPC-23 cells. However, intense cytotoxic effects occurred when no light-curing was performed.

Effects of light-curing time on the cytotoxicity of a restorative composite resin on odontoblast-like cells

This in vitro study evaluated the cytotoxicity of an experimental restorative composite resin subjected to different light-curing regimens. METHODS: Forty round-shaped specimens were prepared and randomly assigned to four experimental groups (n=10), as follows: in Group 1, no light-curing; in Groups 2, 3 and 4, the composite resin specimens were light-cured for 20, 40 or 60 s, respectively. In Group 5, filter paper discs soaked in 5 µL PBS were used as negative controls. The resin specimens and paper discs were placed in wells of 24-well plates in which the odontoblast-like cells MDPC-23 (30,000 cells/cm²) were plated and incubated in a humidified incubator with 5 percent CO2 and 95 percent air at 37ºC for 72 h. The cytotoxicity was evaluated by the cell metabolism (MTT assay) and cell morphology (SEM). The data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (p<0.05). RESULTS: In G1, cell metabolism decreased by 86.2 percent, indicating a severe cytotoxicity of the non-light-cured composite resin. On the other hand, cell metabolism decreased by only 13.3 percent and 13.5 percent in G2 and G3, respectively. No cytotoxic effects were observed in G4 and G5. In G1, only a few round-shaped cells with short processes on their cytoplasmic membrane were observed. In the other experimental groups as well as in control group, a number of spindle-shaped cells with long cytoplasmic processes were found. CONCLUSION: Regardless of the photoactivation time used in the present investigation, the experimental composite resin presented mild to no toxic effects to the odontoblast-like MDPC-23 cells. However, intense cytotoxic effects occurred when no light-curing was performed.

Protective Effect of Sodium Ascorbate on MDPC-23 Odontoblast-Like Cells Exposed to a Bleaching Agent.

OBJECTIVES: To evaluate the cytotoxic effects of a bleaching agent composed of 0.01% carbamide peroxide (CP; 2.21mug/ml H(2)O(2)) on the MDPC-23 odontoblastic cell line, and to determine whether sodium ascorbate (SA) is capable of reducing, or even eliminating, the toxic effects caused by this bleaching agent. METHODS: The cells were seeded in wells and incubated for 48 hours. CP and SA were dissolved in a culture medium (DMEM) in order to obtain experimental extracts. Six groups of cells (n=10) were treated as follows: G1: no treatment (control); G2: 0.25 mM SA/60 min; G3: 0.5 mM SA/60 min; G4: 0.25 mM SA+0.01% CP/60 min; G5: 0.5 mM SA+0.01% CP/60 min; and G6: 0.01% CP/60 min. The cell metabolism was evaluated by MTT assay, and the cell morphology was assessed by scanning electron microscopy. The data obtained were analyzed by 2-way ANOVA and post-hoc Tukey's test (alpha=5%). RESULTS: THE PERCENTAGES OF CELL METABOLISM WERE AS FOLLOWS: G1 (control)=100%; G2=110.06%, G3=108.57%, G4=90.35%, G5=97.63%, and G6=66.88%. Group 6 presented a statistically lower cell metabolism than did the other groups, and the cells that remained on the substrate exhibited changes in their morphology. SA decreased the cytotoxic effects caused by CP, demonstrating its protective effect against the toxic components of this dental product. CONCLUSIONS: It was concluded that CP gel has cytopathic effects on MDPC-23 odontoblastic cells, even at low concentrations such as 0.01%. SA at 0.25 mM, and that 0.5 mM is able to protect these cultured cells against the cytotoxic effects of CP.

Cytotoxic effects of White-MTA and MTA-Bio cements on odontoblast-like cells (MDPC-23).

This study evaluated the cytotoxic effects of 2 mineral trioxide aggregate (MTA) cements - White-MTA-Angelus and a new formulation, MTA-Bio - on odontoblast-like cell (MDPC-23) cultures. Twenty-four disc-shaped (2 mm diameter x 2 mm thick) specimens were fabricated from each material and immersed individually in wells containing 1 mL of DMEM culture medium for either 24 h or 7 days to obtain extracts, giving rise to 4 groups of 12 specimens each: G1 - White-MTA/24 h; G2 - White-MTA/7 days; G3 - MTA-Bio/24 h; and G4 - MTA-Bio/7 days. Plain culture medium (DMEM) was used as a negative control (G5). Cells at 30,000 cells/cm(2) concentration were seeded in the wells of 24-well plates and incubated in a humidified incubator with 5% CO2 and 95% air at 37 degrees C for 72 h. After this period, the culture medium of each well was replaced by 1 mL of extract (or plain DMEM in the control group) and the cells were incubated for additional 2 h. Cell metabolism was evaluated by the MTT assay and the data were analyzed statistically by ANOVA and Tukey's test (alpha=0.05). Cell morphology and the surface of representative MTA specimens of each group were examined by scanning electron microscopy. There was no statistically significant difference (p>0.05) between G1 and G2 or between G3 and G4. No significant difference (p>0.05) was found between the experimental and control groups either. Similar cell organization and morphology were observed in all groups, regardless of the storage periods. However, the number of cells observed in the experimental groups decreased compared to the control group. MTA-Bio presented irregular surface with more porosities than White-MTA. In conclusion, White-MTA and MTA-Bio presented low cytotoxic effects on odontoblast-like cell (MDPC-23) cultures.

Toxicity of chlorhexidine on odontoblast-like cells.

UNLABELLED: Chlorhexidine gluconate (CHX) is recommended for a number of clinical procedures and it has been pointed out as a potential cavity cleanser to be applied before adhesive restoration of dental cavities. OBJECTIVE: As CHX may diffuse through the dentinal tubules to reach a monolayer of odontoblasts that underlies the dentin substrate, this study evaluated the cytotoxic effects of different concentrations of CHX on cultured odontoblast-like cells (MDPC-23). MATERIAL AND METHODS: Cells were cultured and exposed to CHX solutions at concentrations of 0.06%, 0.12%, 0.2%, 1% and 2%. Pure culture medium (alpha-MEM) and 3% hydrogen peroxide were used as negative and positive control, respectively. After exposing the cultured cells to the controls and CHX solutions for 60 s, 2 h or 60 s with a 24-h recovery period, cell metabolism (MTT assay) and total protein concentration were evaluated. Cell morphology was assessed under scanning electron microscopy. CHX had a dose-dependent toxic effect on the MDPC-23 cells. RESULTS: Statistically significant difference was observed when the cells were exposed to CHX in all periods (p<0.05). Significant difference was also determined for all CHX concentrations (p<0.05). The 60-s exposure time was the least cytotoxic (p<0.05), while exposure to CHX for 60 s with a 24-h recovery period was the most toxic to the cells (p<0.05). CONCLUSION: Regardless of the exposure time, all CHX concentrations had a high direct cytotoxic effect to cultured MDPC-23 cells.

Transdentinal protective role of sodium ascorbate against the cytopathic effects of H2O2 released from bleaching agents.

OBJECTIVES: The objectives of this study were to evaluate the transdentinal cytotoxicity of 10% and 16% carbamide peroxide gel (CP), as well as the ability of the antioxidant, 10% sodium ascorbate (SA), to protect the odontoblasts in culture. STUDY DESIGN: Human dentin discs of 0.5-mm thickness were obtained and were placed into artificial pulp chambers. MDPC-23 odontoblastlike cells were seeded on pulp surface of the discs and the following groups were established: G1-No Treatment (control), G2-10% SA/6hs, G3-10%/CP6hs, G4-10%SA/6hs+10%CP/6hs, G5-16%CP/6hs, and G6-10%SA/6hs+16%CP/6hs. The cell viability was measured by the MTT assay. RESULTS: In groups where 16% CP was used, decreased cell viability was observed. Conversely, the application of 10% SA on the dentin discs, before the use of the CP, reduced the cytotoxic effects of these products on cells. CONCLUSIONS: The 16% CP cause a significant decrease in MDPC-23 cell viability and 10% SA was able to partially prevent the toxic effects of CP.

Toxicity of chlorhexidine on odontoblast-like cells

Chlorhexidine gluconate (CHX) is recommended for a number of clinical procedures and it has been pointed out as a potential cavity cleanser to be applied before adhesive restoration of dental cavities. OBJECTIVE: As CHX may diffuse through the dentinal tubules to reach a monolayer of odontoblasts that underlies the dentin substrate, this study evaluated the cytotoxic effects of different concentrations of CHX on cultured odontoblast-like cells (MDPC-23). MATERIAL AND METHODS: Cells were cultured and exposed to CHX solutions at concentrations of 0.06 percent, 0.12 percent, 0.2 percent, 1 percent and 2 percent. Pure culture medium (á-MEM) and 3 percent hydrogen peroxide were used as negative and positive control, respectively. After exposing the cultured cells to the controls and CHX solutions for 60 s, 2 h or 60 s with a 24-h recovery period, cell metabolism (MTT assay) and total protein concentration were evaluated. Cell morphology was assessed under scanning electron microscopy. CHX had a dose-dependent toxic effect on the MDPC-23 cells. RESULTS: Statistically significant difference was observed when the cells were exposed to CHX in all periods (p<0.05). Significant difference was also determined for all CHX concentrations (p<0.05). The 60-s exposure time was the least cytotoxic (p<0.05), while exposure to CHX for 60 s with a 24-h recovery period was the most toxic to the cells (p<0.05). CONCLUSION: Regardless of the exposure time, all CHX concentrations had a high direct cytotoxic effect to cultured MDPC-23 cells.

Cytotoxic effects of White-MTA and MTA-Bio cements on odontoblast-like cells (MDPC-23)

This study evaluated the cytotoxic effects of 2 mineral trioxide aggregate (MTA) cements - White-MTA-Angelus and a new formulation, MTA-Bio - on odontoblast-like cell (MDPC-23) cultures. Twenty-four disc-shaped (2 mm diameter x 2 mm thick) specimens were fabricated from each material and immersed individually in wells containing 1 mL of DMEM culture medium for either 24 h or 7 days to obtain extracts, giving rise to 4 groups of 12 specimens each: G1 - White-MTA/24 h; G2 - White-MTA/7 days; G3 - MTA-Bio/24 h; and G4 - MTA-Bio/7 days. Plain culture medium (DMEM) was used as a negative control (G5). Cells at 30,000 cells/cm² concentration were seeded in the wells of 24-well plates and incubated in a humidified incubator with 5 percent CO2 and 95 percent air at 37ºC for 72 h. After this period, the culture medium of each well was replaced by 1 mL of extract (or plain DMEM in the control group) and the cells were incubated for additional 2 h. Cell metabolism was evaluated by the MTT assay and the data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Cell morphology and the surface of representative MTA specimens of each group were examined by scanning electron microscopy. There was no statistically significant difference (p>0.05) between G1 and G2 or between G3 and G4. No significant difference (p>0.05) was found between the experimental and control groups either. Similar cell organization and morphology were observed in all groups, regardless of the storage periods. However, the number of cells observed in the experimental groups decreased compared to the control group. MTA-Bio presented irregular surface with more porosities than White-MTA. In conclusion, White-MTA and MTA-Bio presented low cytotoxic effects on odontoblast-like cell (MDPC-23) cultures.

Este estudo avaliou o efeito citotóxico de dois cimentos MTA - MTA Branco-Angelus e uma nova formulação, MTA-Bio - sobre células odontoblastóides (MDPC-23) mantidas em cultura. Vinte e quatro espécimes padronizados (2 mm diâmetro x 2 mm largura) foram confeccionados de cada material e imersos individualmente em compartimentos contendo 1 mL de meio de cultura DMEM por 24 h ou 7 dias para obtenção dos extratos, formando 4 grupos de 12 espécimes cada: G1 - MTA-Branco/24 h; G2 - MTA-Branco/7 dias; G3 - MTA-Bio/24 h; e G4 - MTA-Bio/7 dias. Meio de cultura puro (DMEM) foi utilizado como controle negativo (G5). Células na concentração de 30.000 células/cm² foram semeadas nas placas de 24 compartimentos e incubadas em incubadora com 5 por cento CO2 e 95 por cento ar a 37ºC por 72 h. Após esse período, o meio de cultura de cada compartimento foi substituído por 1 mL do extrato (ou DMEM puro no grupo controle) e as células foram incubadas pelo período adicional de 2 h. O metabolismo celular foi avaliado pelo teste do MTT e os dados foram analisados estatisticamente pelo teste de ANOVA e Tukey (α=0,05). A morfologia celular e da superfície dos espécimes de MTA representativos de cada grupo foram avaliados em microscopia eletrônica de varredura. Não houve diferença estatisticamente significante (p>0,05) entre os gurpos G1 e G2 ou entre G3 e G4. Não foi encontrada diferença estatística (p>0,05) entre os grupos experimentais e controle. Morfologia e organização celular semelhante foram observadas em todos os grupos, independente do período de extração. Entretanto, o número de células observado nos grupos experimentais diminui quando comparado ao grupo controle. MTA-Bio apresentou uma superfície irregular com mais porosidades que o MTA-Branco. Pode-se concluir que os cimentos MTA-Branco e MTA-Bio apresentaram reduzido efeito citotóxico sobre células odontoblastóides (MDPC-23) mantidas em cultura.

Direct and transdentinal antibacterial activity of chlorhexidine.

PURPOSE: To evaluate the antibacterial effect of different chlorhexidine (CHX) concentrations against Streptococcus mutans using the agar-diffusion method with and without human dentin discs placed between the bacteria and the test substances. METHODS: For the direct application (agar-well technique), a base layer containing 15 mL of BHI agar and 300 microL of S. mutans inoculum (10(9) cfu/mL) was prepared in Petri dishes. Six wells per dish were made at equidistant points and immediately filled with CHX gels (0.12%, 0.2%, 1% and 2%), 35% phosphoric acid and pure natrosol (n = 6 wells/substance). Paper discs soaked in sterile distilled water served as control group (n = 6). For the indirect application (transdentinal diffusion), 0.2 mm- and 0.5 mm-thick human dentin discs (36 discs/thickness) had the hydraulic conductance determined, which allowed the homogeneous allocation of them to the experimental and control groups. The discs were placed at equidistant points on the Petri dishes containing BHI with the S. mutans inoculum (six discs per dish; one per substance) with the pulpal side in contact with the bacteria. In the discs treated with CHX gels, dentin surface was etched with H3PO4 and rinsed with distilled water before CHX gel application for 1 minute. After both direct and indirect application, the dishes were incubated for 24 hours and the bacterial growth inhibition zones formed around the wells and dentin discs were measured. Data were analyzed statistically by the non-parametric Kruskal-Wallis and Mann-Whitney tests at 5% significance level. RESULTS: In the direct test, all CHX concentrations presented a dose-dependent antibacterial activity against S. mutans. In the indirect test, there were statistically significant differences (P < 0.05) among all groups and the largest microbial growth inhibition zones were observed when 2% CHX was applied on 0.2 mm-thick discs (P < 0.05). It was concluded that all evaluated CHX gels exhibited both direct and transdentinal antibacterial activity against S. mutans. This effect of CHX was strongly influenced by the CHX concentration as well as the dentin barrier thickness.

Transdentinal cytotoxic effects of different concentrations of chlorhexidine gel applied on acid-conditioned dentin substrate.

It has been demonstrated that chlorhexidine digluconate (CHX) is capable of eliminating bacteria that may remain lodged in dentin after mechanical caries removal. In addition, the use of CHX on acid-etched dentin before adhesive system application delays the resin-dentin interface degradation, maintaining the integrity of the adhesive restorations. Despite these advantages of using CHX in restorative dentistry, when applied on dentin, this chemical agent may diffuse across dentinal tubules to cause toxic effects to the pulp cells. The aim of this study was to evaluate the transdentinal cytotoxic effects caused by different concentrations of CHX gels applied on acid-conditioned dentin substrate. Dentin discs (0.2-mm and 0.5-mm thick) were cut from human third molars and mounted in artificial pulp chambers. Odontoblast-like MDPC-23 cells (50,000 cells/cm(2)) were seeded on the pulpal side of the discs, and the carbon polymer gel (natrosol) with different CHX concentrations (0.12, 0.2, 1, and 2%), 35% phosphoric acid, or pure natrosol were applied on the occlusal side of the discs, forming six treatment groups (n = 10 discs/thickness). The dentin discs in the control group (n = 10 discs/thickness) did not receive any treatment. In each group, cell metabolism was analyzed by the methyltetrazolium assay (n = 8/thickness), and cell morphology was assessed by scanning electron microscopy (n = 2/thickness). Statistical analysis showed that CHX gels had a dose-dependent toxic effect on the odontoblast-like cells. Cell metabolism decreased by 12.8, 14.6, 18.3, 26, 13.7, and 10.5% for the 0.5-mm-thick dentin discs and 23, 26.3, 28.1, 34.5, 22.5, and 19.4% for the 0.2-mm-thick dentin discs treated with 0.12% CHX, 0.2% CHX, 1% CHX, 2% CHX, H(3)PO(4), and pure natrosol, respectively. According to the experimental conditions of the current investigation, it may be concluded that the application of natrosol gel with different concentrations of CHX on acid-conditioned dentin causes mild transdentinal cytotoxic effects to the MDPC-23 cells in a dose-dependent manner. Dentin acted as a biological barrier against CHX diffusion, and this effect was directly related to dentin thickness.

Cytotoxic effect of a 35% hydrogen peroxide bleaching gel on odontoblast-like MDPC-23 cells.

OBJECTIVE: This study evaluated transenamel and transdentinal cytotoxic effects of a bleaching gel on the MDPC-23 cell line. STUDY DESIGN: Discs obtained from bovine incisors were placed in a metallic device to simulate an in vivo pulp chamber. Groups were formed according to the enamel surface treatment: G1: 35% H(2)O(2) bleaching gel; G2: 35% H(2)O(2) bleaching gel + halogen light; G3: halogen light; and G4: control. Cell metabolism was evaluated by the methyltetrazolium assay and cell morphology by scanning electron microscopy. RESULTS: Cell metabolism decreased by 31.7%, 41.6%, and 11.5% in G1, G2, and G3, respectively. Cytotoxic effects observed in G2 were significantly more severe compared with G3 and G4. In G1 and G2, a smaller number of viable cells with major morphologic alterations remained adhered to dentin. CONCLUSION: The bleaching gel associated with light presented transenamel and transdentinal cytotoxic effects characterised by direct damage to odontoblasts and decrease of their metabolic activity.

Cytotoxicity of resin-based light-cured liners.

PURPOSE: To evaluate the cytotoxic effects of resin-based light-cured liners on culture of pulp cells. METHODS: Discs measuring 4 mm in diameter and 2 mm thick were fabricated from TheraCal (TCMTA), Vitrebond (VIT), and Ultrablend Plus (UBP). These specimens were immersed in serum-free culture medium (DMEM) for 24 hours or 7 days to produce the extracts. After incubating the pulp cells for 72 hours, the extracts were applied on the cells and the cytotoxic effects were determined based on the cell metabolism (MTT), total protein expression and cell morphology (SEM). In the control group, fresh DMEM was used. Data from MTT analysis and protein expression were submitted to Kruskal-Wallis and Mann-Whitney tests at the preset level of significance of 5%. RESULTS: When in contact with the 24-hour extract, TCMTA, VIT, and UBP decreased the cell metabolism by 31.5%, 73.5% and 71.0%, respectively. The total protein expressed by the cells in contact with VIT and UBP was lower than TCMTA and DMEM (Mann-Whitney, P < 0.05). When in contact with the 7-day extract, TCMTA, VIT, and UBP decreased the metabolic activity by 45.9%, 77.1% and 64.4%, respectively. All the liners expressed statistically lower amounts of proteins when compared to the control. A reduction in the number of cells was observed for all liners. The remaining cells from TCMTA group resembled those from the control group while for VIT and UBP the cells presented significant morphological alterations.

Cytotoxic effects of different concentrations of a carbamide peroxide bleaching gel on odontoblast-like cells MDPC-23.

This study evaluated the cytotoxic effects of a carbamide peroxide (CP) bleaching gel at different concentrations on odontoblast-like cells. Immortalized cells of the MDPC-23 cell line (30,000 cells/cm(2)) were incubated for 48 h. The bleaching gel was diluted in DMEM culture medium originating extracts with different CP concentrations. The amount (microg/mL) of hydrogen peroxide (H(2)O(2)) released from each extract was measured by the leukocrystal violet/horseradish peroxidase enzyme assay. Five groups (n = 10) were formed according to the CP concentration in the extracts: G1-DMEM (control); G2-0.0001% CP (0.025 microg/mL H(2)O(2)); G3-0.001% CP (0.43 microg/mL H(2)O(2)); G4-0.01% CP (2.21 microg/mL H(2)O(2)); and G5-0.1% CP (29.74 microg/mL H(2)O(2)). MDPC-23 cells were exposed to the bleaching gel extracts for 60 min and cell metabolism was evaluated by the MTT assay. Data were analyzed statistically by one-way ANOVA and Tukey's test (alpha = 0.05). Cell morphology was examined by scanning electron microscopy. The percentages of viable cells were as follows: G1, 100%; G2, 89.41%; G3, 82.4%; G4, 61.5%; and G5, 23.0%. G2 and G3 did not differ significantly (p > 0.05) from G1. The most severe cytotoxic effects were observed in G3 and G4. In conclusion, even at low concentrations, the CP gel extracts presented cytotoxic effects. This cytotoxicity was dose-dependent, and the 0.1% CP concentration caused the most intense cytopathic effects to the MDPC-23 cells.

Citotoxicidade direta e transdentinária da clorexidina sobre células odontoblastóides MDPC-23 e análise de sua atividade antimicrobiana in vitro / Direct and transdentinal toxicity of chlorhexidine on odontoblast cell line MDPC-23 and its antibacterial activity

O objetivo da presente pesquisa foi avaliar o efeito citotóxico direto etransdentinário de diferentes concentrações de clorexidina (CHX), bem como sua atividade antibacteriana. Para isto, concentrações de 0,06%;0,12%; 0,2%; 1% e 2% de CHX foram aplicadas sobre células odontoblastóides MDPC-23 em cultura (teste direto). Além disto, as concentrações de CHX também foram aplicadas sobre a superfície oclusal de discos de dentina de 0,5mm ou 0,2mm de espessura, os quais apresentavam células MDPC-23 cultivadas sobre sua superfície pulpar(teste indireto). O metabolismo e morfologia celular foram avaliados peloteste de MTT e pela análise em MEV, respectivamente. O potencialantibacteriano da CHX foi avaliado sobre S.mutans com e sem interposição de discos de dentina. Os dados numéricos obtidos dos experimentos realizados foram submetidos à análise estatística. Aredução do metabolismo celular provocado pela CHX mostrou-se dose etempo dependentes. Foi demonstrado ainda que quanto menor a espessura do disco de dentina e maior a concentração da CHX, mais intensos são os efeitos tóxicos deste agente químico sobre as células pulpares em cultura, e mais efetiva é a atividade antibacteriana da CHX sobre S.mutans. Foi possível concluir que o intenso efeito tóxico diretoobservado para a CHX é notavelmente reduzido pela interposição de barreiras de dentina, cuja espessura interfere no metabolismo das células pulpares MDPC-23. Além disso, a CHX difunde através dos túbulos dentinários exercendo efeito antibacteriano contra S.mutans.

Citotoxicidade direta e transdentinária da clorexidina sobre células odontoblastóides MDPC-23 e análise de sua atividade antimicrobiana in vitro / Direct and transdentinal toxicity of chlorhexidine on odontoblast cell line MDPC-23 and its antibacterial activity

O objetivo da presente pesquisa foi avaliar o efeito citotóxico direto e transdentinário de diferentes concentrações de clorexidina (CHX), bem como sua atividade antibacteriana. Para isto, concentrações de 0,06%; 0,12%; 0,2%; 1% e 2% de CHX foram aplicadas sobre células odontoblastóides MDPC-23 em cultura (teste direto). Além disto, as concentrações de CHX também foram aplicadas sobre a superfície oclusal de discos de dentina de 0,5mm ou 0,2mm de espessura, os quais apresentavam células MDPC-23 cultivadas sobre sua superfície pulpar (teste indireto). O metabolismo e morfologia celular foram avaliados pelo teste de MTT e pela análise em MEV, respectivamente. O potencial antibacteriano da CHX foi avaliado sobre S.mutans com e sem interposição de discos de dentina. Os dados numéricos obtidos dos experimentos realizados foram submetidos à análise estatística. A redução do metabolismo celular provocado pela CHX mostrou-se dose e tempo dependentes. Foi demonstrado ainda que quanto menor a espessura do disco de dentina e maior a concentração da CHX, mais intensos são os efeitos tóxicos deste agente químico sobre as células pulpares em cultura, e mais efetiva é a atividade antibacteriana da CHX sobre S.mutans. Foi possível concluir que o intenso efeito tóxico direto observado para a CHX é notavelmente reduzido pela interposição de barreiras de dentina, cuja espessura interfere no metabolismo das células pulpares MDPC-23. Além disso, a CHX difunde através dos túbulos dentinários exercendo efeito antibacteriano contra S.mutans.

The aim of this in vitro study was to evaluate the direct and transdentinal cytotoxicity of different concentrations of chlorhexidine (CHX) and its antibacterial activity. The following concentrations of CHX: 0.06%; 0.12%; 0.2%; 1%; and 2% were applied directly on odontoblast-cell line MDPC-23 or on the occlusal surface of dentin discs (0.5mm or 0.2mm thick) which presented pulp cells seeded on their pulpal surface. Cell metabolic activity and morphology were evaluated by MTT assay and SEM, respectively. The influence of dentin thickness on the antibacterial activity of CHX against S. mutans was also assessed. The data were submitted to the statistical analysis of Mann-Whitney. Reduction in the cell metabolism from 42% to 78% was observed according to the concentration of CHX and its period of application on the cells. Therefore, the direct cytotoxicity of CHX is dose and time dependent. It was also observed that the most intense toxic effects occurred as thicker was the dentin disc and as higher was the concentration of CHX. Antibacterial activity against S. mutans was observed to the highest concentration of CHX. It was concluded that the intense cytotoxicity of all concentrations of CHX applied directly on the MDPC-23 cells is notably reduced by the presence of dentin discs interposed between this chemical agent and the cultured cells. In addition, the transdentinal diffusion of CHX causes antibacterial activity against S. mutans.

In-vivo evaluation of the bacterial contamination and disinfection of acrylic baseplates of removable orthodontic appliances.

INTRODUCTION: This randomized clinical trial assessed, by using microbial culture and scanning electron microscopy (SEM), the contamination by mutans streptococci (MS) colonies/biofilms on acrylic baseplates of removable orthodontic appliances and evaluated the efficacy of antimicrobial sprays (Periogard [Colgate-Palmolive Ind. Brasileira, Osasco, SP, Brazil], Cepacol [Merrell Lepetit Farmacêutica e Industrial Ltda, Santo Amaro, SP, Brazil], and sterile tap water [control]) on their disinfection. METHODS: Seventeen children were randomly enrolled in a 3-stage changeover system with a 1-week interval between each stage. All solutions were used in all stages by a different group of children. The acrylic baseplates were worn full time except at meals. At the end of each week of the trial, the baseplates were submitted to a randomized disinfection protocol and were sent for microbiologic analysis. New baseplates were constructed, and the same sequence of procedures was repeated 2 more times. Acrylic baseplates representing each test solution were examined by SEM. The Friedman test assessed differences at the 5% significance level among the solutions for MS biofilm formation on acrylic surface. RESULTS: Cepacol and Periogard reduced the formation of MS colonies/biofilms, and both solutions differed statistically from sterile tap water (P <.001). However, Periogard was significantly more effective against MS than Cepacol (P <.001). When MS colonies/biofilms were detected on acrylic surfaces under stereomicroscopy, this was confirmed with SEM. CONCLUSIONS: Acrylic baseplates of removable orthodontic appliances worn by children were contaminated by MS colonies/biofilms in all cases after 1 week. Although Cepacol had better results than sterile tap water, spraying with Periogard showed significantly greater efficacy in reducing MS colonies/biofilms on acrylic surfaces.

Shear bond strength to primary enamel: influence of Er:YAG laser irradiation distance.

PURPOSE: The purpose of this study was to evaluate in vitro the influence of Er:YAG laser irradiation distance on the shear bond strength of an adhesive restorative system to primary enamel. METHODS: Fifty buccal surfaces of extracted human canines were ground and divided into 5 groups (N=10). The control group was etched with 35% phosphoric acid (CA). In the lased groups, the enamel surface treatment was performed with the Er:YAG laser (80mJ/2Hz) by varying the irradiation distance (12, 14, 16, and 17 mm), followed by acid etching. An adhesive agent (Single Bond) was applied on the bonding sites, and resinous cylinders (Filtek Z250) were prepared. Shear bond strength tests were performed in a universal testing machine (0.5 mm/minute). Failure mode was assessed using a X40 magnification stereomicroscope. Data were submitted to statistical analysis by analysis of variance. RESULTS: The means in MPa were: (1) CA=18.76 (+/-6.68); (2) 12 mm=12.73 (+/-5.46); (3) 14 mm=15.9 (+/-6.81); (4) 16 mm=20.1 (+/-6.94); and (5) 17 mm=15.15 (+/-6.81). There was no statistically significant difference (P<.05) among the tested groups. CONCLUSION: The different Er:YAG laser distance irradiations did not influence the adhesive resistance of the resinous system to enamel, even when compared with the control group (acid etching solely).

Síndrome de Alagille: relato de caso / Alagille syndrome: case report

A síndrome de Alagille ou displasia artério-hepática é uma doença hereditária rara, autossômica dominante. Além de apresentarem anomalias no fígado, os portadores desta síndrome, freqüentemente, apresentam alterações no coração, nas vértebras, na face e nos olhos. O presente trabalho tem como objetivo relatar o tratamento odontológico de um paciente portador da síndrome de Alagille, dando ênfase aos cuidados adotados, em função dos problemas sistêmicos associados à síndrome em questão