In situ evaluation of fluoride-, stannous- and polyphosphate-containing solutions against enamel erosion

Objective To evaluate the anti-erosive effect of solutions containing sodium fluoride (F: 225 ppm of fluoride), sodium fluoride + stannous chloride (F + Sn: 225 ppm of fluoride + 800 ppm of stannous), sodium fluoride + stannous chloride + sodium linear polyphosphate (F + Sn + LPP: 225 ppm of fluoride + 800 ppm of stannous + 2% of sodium linear polyphosphate), and deionized water (C: control), using a four-phase, single-blind, crossover in situ clinical trial. Methods In each phase, 12 volunteers wore appliances containing 4 enamel specimens, which were submitted to a 5-day erosion-remineralization phase that consisted of 2 h of salivary pellicle formation with the appliance in situ, followed by 2 min extra-oral immersion in 1% citric acid (pH 2.4), 6x/day, with 90 min of exposure to saliva in situ between the challenges. Treatment with the test solutions was performed extra-orally for 2 min, 2x/day. At the end of the experiment, surface loss (SL, in μm) was evaluated by optical profilometry. Data were analyzed using ANOVA and Tukey tests (α = 0.05). The surface of additional specimens was evaluated by x-ray diffraction after treatments (n = 3). Results C (mean SL ± standard-deviation: 5.97 ± 1.70) and F (5.36 ± 1.59) showed the highest SL, with no significant difference between them (p > 0.05). F + Sn (2.68 ± 1.62) and F + Sn + LPP (2.10 ± 0.95) did not differ from each other (p > 0.05), but presented lower SL than the other groups (P < 0.05). Apatite and stannous deposits on specimen surfaces were identified in the x-ray analysis for F + Sn and F + Sn + LPP. Conclusions Sodium fluoride solution exhibited no significant anti-erosive effect. The combination between sodium fluoride and stannous chloride reduced enamel erosion, irrespective of the presence of linear sodium polyphosphate. Clinical significance Under highly erosive conditions, sodium fluoride rinse may not be a suitable alternative to prevent enamel erosion. A rinse containing sodium fluoride and stannous chloride was shown to be a better treatment option, which was not further improved by addition of the sodium linear polyphosphate

Applying the maternal near miss approach for the evaluation of quality of obstetric care: a worked example from a multicenter surveillance study

To assess quality of care of women with severe maternal morbidity and to identify associated factors. This is a national multicenter cross-sectional study performing surveillance for severe maternal morbidity, using the World Health Organization criteria. The expected number of maternal deaths was calculated with the maternal severity index (MSI) based on the severity of complication, and the standardized mortality ratio (SMR) for each center was estimated. Analyses on the adequacy of care were performed. 17 hospitals were classified as providing adequate and 10 as nonadequate care. Besides almost twofold increase in maternal mortality ratio, the main factors associated with nonadequate performance were geographic difficulty in accessing health services (P < 0.001), delays related to quality of medical care (P = 0.012), absence of blood derivatives (P = 0.013), difficulties of communication between health services (P = 0.004), and any delay during the whole process (P = 0.039). This is an example of how evaluation of the performance of health services is possible, using a benchmarking tool specific to Obstetrics. In this study the MSI was a useful tool for identifying differences in maternal mortality ratios and factors associated with nonadequate performance of care.To assess quality of care of women with severe maternal morbidity and to identify associated factors. Method. This is a national multicenter cross-sectional study performing surveillance for severe maternal morbidity, using the World Health Organization c110CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO402702/2008-

Analysis of the progression of dentine erosion after Nd:YAG irradiation and fluoride

Devido à alta prevalência da erosão dental, esse trabalho tem por objetivo avaliar diferentes protocolos do laser de Nd:YAG e flúor na progressão de lesões de erosão em dentina. Para isso, o trabalho foi divido em duas etapas. Na primeira, foram utilizados 120 terceiros molares humanos que tiveram sua dentina exposta e incluída em resina acrílica. Após polimento, as amostras com curvatura de até 0,3 ?m foram selecionadas. Estas ficaram 10 minutos em ácido cítrico 1% (pH 2,3) para formação de lesão de erosão inicial e então, foram divididas em 8 grupos experimentais (n=15): Controle (sem tratamento), Flúor (gel de fluoreto de sódio neutro 2%), Nd:YAG1 (0,5W; 50mJ; ~41,66J/cm2; 10Hz; 40s; em contato), Nd:YAG2 (0,70W; 70mJ; ~62,50J/cm2; 10Hz; 40s; em contato), Nd:YAG3 (1,0W; 100mJ; ~54,16J/cm2; 10Hz; 40s; 1mm desfocado), Flúor+Nd:YAG1, Flúor+Nd:YAG2 e Flúor+Nd:YAG3. Para verificar a perda de superfície ocorrida, foram feitas leituras em perfilômetro óptico nos seguintes tempos: após formação da lesão inicial, logo após tratamentos e após 1o, 3o e 5o dias de ciclagem erosiva. Para a segunda etapa, foram utilizadas 93 dentinas extraídas de terceiros molares humanos, as quais também foram incluídas em resina acrílica e polidas. Das amostras obtidas, foram selecionadas 60 com curvatura adequada para as análises perfilométricas, nos mesmos tempos descritos anteriormente. As outras 33 amostras foram utilizadas para análise em microscopia eletrônica de varredura, nos tempos pós-lesão inicial, pós-tratamento e ao final dos cinco dias de ciclagem erosiva. Após formação da lesão inicial, elas foram divididas em 6 grupos experimentais: Controle (nenhum tratamento), Flúor (gel de fluoreto de sódio neutro 2%), Nd:YAG1 (0,5W; 50mJ; ~26,6J/cm2; 10Hz; 40s; 1mm desfocado), Nd:YAG2 (0,7W; 70mJ; ~37,5J/cm2; 10Hz; 40s; 1mm desfocado), Flúor+Nd:YAG1 e Flúor+Nd:YAG2. Os dados resultantes das análises perfilométricas foram submetidos à análise estatística, sendo as duas etapas independentes. Significância estatística foi de 5%. Na primeira etapa, os grupos apresentaram diferença significante em todos os tempos analisados (p<0,001), exceto após lesão inicial. Houve perda superficial após irradiação com todos os protocolos do laser de Nd:YAG. A associação do flúor com o laser não diferiu significativamente do laser isoladamente. O grupo Flúor apresentou os menores valore de perda de superfície e os grupos Nd:YAG2 e Flúor+Nd:YAG2 apresentaram os maiores valores, não havendo diferença entre eles. Na segunda etapa, os grupos também apresentaram diferença significante em todos os tempos (p=0,001). Os grupos Flúor e Flúor+Nd:YAG1, após o primeiro dia de ciclagem, tiveram menor perda de superfície que os outros grupos. Nos outros tempos, os grupos Flúor, Flúor+Nd:YAG1 e Flúor+Nd:YAG2, tiveram menor perda de superfície que o grupo Controle e este não foi diferente dos grupos apenas irradiados com o laser, independente do protocolo. As micrografias foram analisadas qualitativamente e mostraram que o laser nos parâmetros utilizados não foi capaz de obliterar os túbulos dentinários, porém, reduziu o diâmetro dos mesmos. Dentro das limitações de um estudo in vitro, pode-se concluir que o flúor tem papel protetor na progressão da erosão dental e que o laser de Nd:YAG, quando utilizado dentro dos parâmetros adequados, pode ser eficaz no tratamento da erosão dental.Due to the high prevalence of dental erosion, this study aimed to evaluate the progression of dentin erosion after treatment with different protocols of the Nd:YAG laser and fluoride. Thus, this study was divided into two phases. In the first phase, 120 human third molars had their dentin exposed and embedded in acrylic resin. After polishing, specimens with curvature of maximum 0.3 ?m were selected. They were immersed in 1% citric acid (pH 2.3) for 10 minutes to form initial erosion lesion and then they were divided into 8 experimental groups (n=15): Control (no treatment), Fluoride (neutral sodium fluoride gel 2%), Nd:YAG1 (0,5W; 50mJ; ~41,66J/cm2; 10Hz; 40s; contact), Nd:YAG2 (0,70W; 70mJ; ~62,50J/cm2; 10Hz; 40s; contact), Nd:YAG3 (1,0W; 100mJ; ~54,16J/cm2; 10Hz; 40s; 1mm defocused), Fluoride+Nd:YAG1, Fluoride+Nd:YAG2 and Fluoride+Nd:YAG3. Surface loss was evaluated by optical profilometry after initial lesion, right after treatments, and after 1st, 3rd and 5th erosion cycling days. For the second phase, 93 dentin specimens were obtained from human third molars. They were also embedded in acrylic resin and polished. From those specimens, 60 with adequate curvature were selected for the profilometer analysis, which were at the same time points described before. The other 33 specimens were analyzed by scanning electron microscopy, after formation of initial lesion, after treatments and at the end of the five days of erosive cycling. After formation of initial lesion, specimens were divided in six groups: Control (no treatment), Fluoride (neutral sodium fluoride gel 2%), Nd:YAG1 (0,5W; 50mJ; ~26,6J/cm2; 10Hz; 40s; 1mm defocused), Nd:YAG2 (0,7W; 70mJ; ~37,5J/cm2; 10Hz; 40s; 1mm defocused), Fluoride+Nd:YAG1 e Fluoride+Nd:YAG2. Data resulting from profilometer analyzes were subjected to statistical analysis, with the two phases independent. Statistical significance was 5%. In the first phase, all groups showed significant differences in all time periods (p<0.001), except after initial lesion. There was surface loss after irradiation with all Nd:YAG laser protocols. The association of fluoride and laser did not differ significantly from the laser alone. Fluoride had the lowest surface loss values and groups Nd:YAG2 and Fluoride+Nd:YAG2 presented the highest, with no difference between them. In the second phase, the groups also showed statistically differences among them in all time periods (p=0.001). Fluoride and Fluoride+Nd:YAG1 after the first erosive challenge had less surface loss than the other groups. In the other time points, Fluoride, Fluoride+Nd:YAG1 and Fluoride+Nd:YAG2 presented lower surface loss than the Control, which did not differ from those irradiated with Nd:YAG laser only, regardless of the protocol. The micrographs were qualitatively analyzed and showed that laser irradiation at all parameters used, was not able to obliterate the dentinal tubules. Nevertheless, the irradiation caused a reduction in the tubule\'s diameter. Within the limitations of an in vitro study, it can be concluded that fluoride has a protective role in the progression of dental erosion and the Nd:YAG laser can be effective in the treatment of dental erosion when used within the proper parameters

Effect of desensitizing and/or anti-erosive treatments on dentine permeability and surface loss

Esta tese de Doutorado apresenta três estudos in vitro independentes. Na parte 1, avaliou-se a permeabilidade dentinária após tratamentos dessensibilizantes de consultório e a resistência destes à ciclagem erosiva-abrasiva de 5 dias; na parte 2, avaliou-se a permeabilidade dentinária após aplicação de cremes dentais dessensibilizantes e/ou anti-erosivos durante uma ciclagem erosiva-abrasiva de 5 dias; e na parte 3, avaliou-se a perda de superfície dentinária resultante da utilização dos cremes dentais dessensibilizantes e/ou anti-erosivos em um modelo de ciclagem erosiva-abrasiva inicial. Nas partes 1 e 2 os túbulos dentinários dos espécimes de dentina foram abertos com solução de EDTA e a permeabilidade máxima inicial foi analisada (considerada 100%). Na parte 1, os tratamentos dessensibilizantes de consultório foram realizados e a permeabilidade dentinária reavaliada (%Lp-após tratamento). Em ambos estudos, os espécimes passaram por uma ciclagem erosivaabrasiva de 5 dias. Cada dia consistiu em 4 imersões em ácido cítrico (2 min, 1%, pH ~2,6), com exposição à saliva humana clarificada por 60 min entre os desafios erosivos. Trinta minutos após o primeiro e último desafios erosivos, os espécimes foram escovados em máquina de escovação (2 N, 45 ciclos) totalizando 2 minutos de exposição às suspensões formadas por creme dental e saliva humana. Na parte 1, foi utilizado um creme dental fluoretado convencional para todos os grupos e na parte 2, cremes dentais de acordo com cada grupo. Ao final dos 5 dias de ciclagem, a permeabilidade dentinária final (%Lp-após ciclagem) foi avaliada. Os mesmos cremes dentais testados na parte 2 também foram testados quanto à perda de superfície (PS) na parte 3. Para isso, os espécimes tiveram duas partes das superfícies protegidas com uma fita adesiva de forma a deixar uma área central exposta e, então, foram submetidos a 5 ciclos de erosão-abrasão iniciais. Em cada ciclo os espécimes foram imersos em saliva artificial (60 minutos; pH 7), e em ácido cítrico (3 minutos; 1%; pH 3,6). Então, os espécimes foram escovados em máquina de escovação (2 N; 25 ciclos) com as suspensões formadas pela mistura dos cremes dentais com saliva artificial, totalizando 2 minutos de exposição às suspensões. Para cada estudo, os dados de %Lp e PS foram estatisticamente analisados. Parte 1: Os grupos NUPRO e Gluma Desensitizer foram os únicos que apresentaram menor %Lp quando comparados com controle negativo (p=0,026 e p=0,022; respectivamente), em ambos os tempos analisados. Parte 2: Os cremes dentais Regenerate e Sensodyne Pronamel apresentaram menor %Lp em comparação com o grupo controle negativo (p<0,05). Parte 3: Os grupos apresentaram diferentes graus de PS independente da indicação comercial, sendo o Elmex Erosion Protection, o único grupo com baixa PS que se diferenciou do controle positivo (p=0,031). Pode-se concluir que os tratamentos de consultório NUPRO e Gluma Desensitizer e os cremes dentais Regenerate e Sensodyne Pronamel foram os melhores em diminuir a %Lp, no modelo estudado. Em relação à PS, em um modelo de ciclagem erosiva-abrasiva inicial, os cremes dentais apresentaram diferentes graus de PS, independente da indicação comercial, tendo o Elmex Erosion Protection mostrado o resultado mais promissor.This PhD thesis presents three independent in vitro studies. At part 1, dentine permeability was evaluated after in-office desensitizing treatments and their resistance to an erosive-abrasive cycling of 5 days; at part 2, dentine permeability was evaluated after application of desensitizing and/or anti-erosive toothpastes during an erosive-abrasive cycling of 5-day; and at part 3, dentine surface loss resulting from the use of desensitizing and/or anti-erosive toothpastes in an initial erosive-abrasive cycling model was evaluated. At parts 1 and 2 the dentinal tubules were opened with EDTA solution and the initial maximum permeability was analyzed (considered 100%). At part 1, the in-office desensitizing treatments were performed and the dentine permeability was reevaluated (%Lp-after treatment). In both studies, the specimens underwent a 5-day erosive-abrasive cycling. Each day consisted of 4 immersions in citric acid (2 minutes, 1%, pH ~ 2.6), and exposure to clarified human saliva for 60 minutes between the erosive challenges. Thirty minutes after the first and the last erosive challenge, the specimens were brushed in a brushing machine (2 N, 45 cycles) totalizing 2 minutes of exposure to the slurries formed by the mixture of toothpaste and human saliva. At part 1, a regular fluoride toothpaste was used for all groups and at part 2, the toothpastes were used according to each group. After the 5 days of cycling, the final dentine permeability (%Lp-after cycling) was evaluated. The same toothpastes tested at part 2 were also analyzed for surface loss (SL) at part 3. For this, the specimens had two parts of the surfaces protected with an adhesive tape leaving a central area exposed, and then were submitted to 5 cycles of initial erosion-abrasion. In each cycle, the specimens were immersed in artificial saliva (60 minutes, pH 7) and in citric acid (3 minutes, 1%, pH 3.6). Then, the specimens were brushed in a brushing machine (2 N, 25 cycles) with the slurries formed by the mixture of the toothpastes with artificial saliva, also totalizing 2 minutes of exposure to the slurries. For each study, the data of %Lp and SL were statistically analyzed. Part 1: The groups NUPRO and Gluma Desensitizer were the only ones that presented lower %Lp when compared to the negative control (p=0.026 and p=0.022, respectively), at both periods analyzed. Part 2: Regenerate and Sensodyne Pronamel toothpastes presented lower %Lp compared to the negative control group (p<0.05). Part 3: The groups showed different degrees of SL regardless of the claim of the toothpaste. Elmex Erosion Protection was the only group with low SL that differed from the positive control (p=0.031). It can be concluded that the in-office treatments NUPRO and Gluma Desensitizer, and the toothpastes Regenerate and Sensodyne Pronamel were able to significantly reduce the %Lp, in the model studied. Considering the SL, analyzed with an initial erosive-abrasive cycling model, toothpastes presented different degrees of SL, regardless of their claim, and Elmex Erosion Protection showed the most promising results

Effect of desensitizing and/or anti-erosive treatments on dentine permeability and surface loss

Esta tese de Doutorado apresenta três estudos in vitro independentes. Na parte 1, avaliou-se a permeabilidade dentinária após tratamentos dessensibilizantes de consultório e a resistência destes à ciclagem erosiva-abrasiva de 5 dias; na parte 2, avaliou-se a permeabilidade dentinária após aplicação de cremes dentais dessensibilizantes e/ou anti-erosivos durante uma ciclagem erosiva-abrasiva de 5 dias; e na parte 3, avaliou-se a perda de superfície dentinária resultante da utilização dos cremes dentais dessensibilizantes e/ou anti-erosivos em um modelo de ciclagem erosiva-abrasiva inicial. Nas partes 1 e 2 os túbulos dentinários dos espécimes de dentina foram abertos com solução de EDTA e a permeabilidade máxima inicial foi analisada (considerada 100%). Na parte 1, os tratamentos dessensibilizantes de consultório foram realizados e a permeabilidade dentinária reavaliada (%Lp-após tratamento). Em ambos estudos, os espécimes passaram por uma ciclagem erosivaabrasiva de 5 dias. Cada dia consistiu em 4 imersões em ácido cítrico (2 min, 1%, pH ~2,6), com exposição à saliva humana clarificada por 60 min entre os desafios erosivos. Trinta minutos após o primeiro e último desafios erosivos, os espécimes foram escovados em máquina de escovação (2 N, 45 ciclos) totalizando 2 minutos de exposição às suspensões formadas por creme dental e saliva humana. Na parte 1, foi utilizado um creme dental fluoretado convencional para todos os grupos e na parte 2, cremes dentais de acordo com cada grupo. Ao final dos 5 dias de ciclagem, a permeabilidade dentinária final (%Lp-após ciclagem) foi avaliada. Os mesmos cremes dentais testados na parte 2 também foram testados quanto à perda de superfície (PS) na parte 3. Para isso, os espécimes tiveram duas partes das superfícies protegidas com uma fita adesiva de forma a deixar uma área central exposta e, então, foram submetidos a 5 ciclos de erosão-abrasão iniciais. Em cada ciclo os espécimes foram imersos em saliva artificial (60 minutos; pH 7), e em ácido cítrico (3 minutos; 1%; pH 3,6). Então, os espécimes foram escovados em máquina de escovação (2 N; 25 ciclos) com as suspensões formadas pela mistura dos cremes dentais com saliva artificial, totalizando 2 minutos de exposição às suspensões. Para cada estudo, os dados de %Lp e PS foram estatisticamente analisados. Parte 1: Os grupos NUPRO e Gluma Desensitizer foram os únicos que apresentaram menor %Lp quando comparados com controle negativo (p=0,026 e p=0,022; respectivamente), em ambos os tempos analisados. Parte 2: Os cremes dentais Regenerate e Sensodyne Pronamel apresentaram menor %Lp em comparação com o grupo controle negativo (p<0,05). Parte 3: Os grupos apresentaram diferentes graus de PS independente da indicação comercial, sendo o Elmex Erosion Protection, o único grupo com baixa PS que se diferenciou do controle positivo (p=0,031). Pode-se concluir que os tratamentos de consultório NUPRO e Gluma Desensitizer e os cremes dentais Regenerate e Sensodyne Pronamel foram os melhores em diminuir a %Lp, no modelo estudado. Em relação à PS, em um modelo de ciclagem erosiva-abrasiva inicial, os cremes dentais apresentaram diferentes graus de PS, independente da indicação comercial, tendo o Elmex Erosion Protection mostrado o resultado mais promissor.This PhD thesis presents three independent in vitro studies. At part 1, dentine permeability was evaluated after in-office desensitizing treatments and their resistance to an erosive-abrasive cycling of 5 days; at part 2, dentine permeability was evaluated after application of desensitizing and/or anti-erosive toothpastes during an erosive-abrasive cycling of 5-day; and at part 3, dentine surface loss resulting from the use of desensitizing and/or anti-erosive toothpastes in an initial erosive-abrasive cycling model was evaluated. At parts 1 and 2 the dentinal tubules were opened with EDTA solution and the initial maximum permeability was analyzed (considered 100%). At part 1, the in-office desensitizing treatments were performed and the dentine permeability was reevaluated (%Lp-after treatment). In both studies, the specimens underwent a 5-day erosive-abrasive cycling. Each day consisted of 4 immersions in citric acid (2 minutes, 1%, pH ~ 2.6), and exposure to clarified human saliva for 60 minutes between the erosive challenges. Thirty minutes after the first and the last erosive challenge, the specimens were brushed in a brushing machine (2 N, 45 cycles) totalizing 2 minutes of exposure to the slurries formed by the mixture of toothpaste and human saliva. At part 1, a regular fluoride toothpaste was used for all groups and at part 2, the toothpastes were used according to each group. After the 5 days of cycling, the final dentine permeability (%Lp-after cycling) was evaluated. The same toothpastes tested at part 2 were also analyzed for surface loss (SL) at part 3. For this, the specimens had two parts of the surfaces protected with an adhesive tape leaving a central area exposed, and then were submitted to 5 cycles of initial erosion-abrasion. In each cycle, the specimens were immersed in artificial saliva (60 minutes, pH 7) and in citric acid (3 minutes, 1%, pH 3.6). Then, the specimens were brushed in a brushing machine (2 N, 25 cycles) with the slurries formed by the mixture of the toothpastes with artificial saliva, also totalizing 2 minutes of exposure to the slurries. For each study, the data of %Lp and SL were statistically analyzed. Part 1: The groups NUPRO and Gluma Desensitizer were the only ones that presented lower %Lp when compared to the negative control (p=0.026 and p=0.022, respectively), at both periods analyzed. Part 2: Regenerate and Sensodyne Pronamel toothpastes presented lower %Lp compared to the negative control group (p<0.05). Part 3: The groups showed different degrees of SL regardless of the claim of the toothpaste. Elmex Erosion Protection was the only group with low SL that differed from the positive control (p=0.031). It can be concluded that the in-office treatments NUPRO and Gluma Desensitizer, and the toothpastes Regenerate and Sensodyne Pronamel were able to significantly reduce the %Lp, in the model studied. Considering the SL, analyzed with an initial erosive-abrasive cycling model, toothpastes presented different degrees of SL, regardless of their claim, and Elmex Erosion Protection showed the most promising results

Effect of titanium tetrafluoride/sodium fluoride solutions containing chitosan at different viscosities on the protection of enamel erosion in vitro.

OBJECTIVE The aim of this in vitro study was to evaluate the protective effect against enamel erosion of experimental solutions containing TiF4/NaF and Chitosan compared to a commercial SnCl2/NaF/AmF solution. DESIGN Bovine enamel samples were divided (n = 15/group) into: (1) commercial solution SnCl2/NaF/AmF (500 ppm F-, positive control); (2) NaF/TiF4 (490 ppm F-); (3) similar to 2 plus 0.5 % chitosan (Ch) (500 mPas), (4) similar to 2 plus 0.5 % chitosan (2000 mPas), (5) negative control (water), (6) 0.5 % chitosan (500 mPas) and (7) 0.5 % chitosan (2000 mPas). The samples were submitted to a pH cycling (0.1 % citric acid, 4 × 90 s/day, interposed by artificial saliva) and daily treatment application (after the last erosive challenge, 1 × 30 s/day) for seven days. After the first day, the surface reflection intensity changes (% rSRI) were measured. After 7 days, the erosive enamel loss was quantified by contact profilometer. The % rSRI and the enamel loss (μm) were compared using ANOVA/Tukey and Kruskal-Wallis/Dunn, respectively (p < 0.05). RESULTS The solution containing TiF4/NaF plus Ch 500 mPas was the only able to reduce the early erosive demineralization compared to negative control (p = 0.003). However, it did not differ from the other solutions. Enamel samples treated with SnCl2/NaF/AmF presented the lowest median loss value [0.72 (0.18) μm] followed by both TiF4 + Ch [1.24 (0.49) and 1.28 (0.25)]; which significantly differed from the negative control [1.70 (0.27)]. CONCLUSION The experimental solution containing TiF4/NaF plus chitosan (2000 mPas) has comparable effect to SnCl2/NaF/AmF on the protection against enamel erosion

Chemical and physical factors of desensitizing and/or anti-erosive toothpastes associated with lower erosive tooth wear.

Toothpastes have a complex formulation and their different chemical and physical factors will influence their effectiveness against erosive tooth wear (ETW). We, therefore, investigated the effect of different desensitizing and/or anti-erosive toothpastes on initial enamel erosion and abrasion, and analysed how the interplay of their chemical and physical factors influences ETW. Human enamel specimens were submitted to 5 erosion-abrasion cycles using 9 different toothpastes and an artificial saliva group, and enamel surface loss (SL) was calculated. Chemical and physical factors (pH; presence of tin; calcium, phosphate and fluoride concentrations; % weight of solid particles; wettability; and particle size) of the toothpaste slurries were then analysed and associated with the amount of SL in a multivariate model. We observed that all desensitizing and/or anti-erosive toothpastes presented different degrees of SL. Besides pH and fluoride, all other chemical and physical factors were associated with SL. The results of this experiment indicate that enamel SL occurs independent of whether the toothpastes have a desensitizing or anti-erosive claim, and that lower SL is associated with the presence of tin, higher concentration of calcium and phosphate, higher % weight of solid particles, smaller particle size, and lower wettability

Influence of desensitizing and anti-erosive toothpastes on dentine permeability: An in vitro study.

OBJECTIVE This study analyzed the effect of desensitizing and/or anti-erosive toothpastes on dentine permeability. METHODS One-mm dentin discs were prepared from human molars and exposed to EDTA solution (5 min, 17%). Initial dentine permeability was measured, under constant pressure. Specimens were randomly allocated into 10 groups: four anti-erosive toothpastes (calcium silicate + sodium phosphate, potassium nitrate, stannous chloride + chitosan, oligopeptide-104); four desensitizing toothpastes (arginine + calcium carbonate, calcium sodium phosphosilicate, strontium acetate, stannous fluoride); and two controls (regular fluoridated toothpaste, and human saliva). They were submitted to a 5-day erosion-abrasion cycling model. Erosion consisted of immersion in citric acid (2 min, 0.3%, natural pH ˜ 2.6, 4x/day), followed by 1 h exposure to human saliva. Specimens were brushed for 15 s (2 N, 45 strokes) with the toothpaste slurries (total exposure time of 2 min). After 5 cycles, the final dentine permeability was determined. Dentine permeability change was calculated as a percentage of the initial hydraulic conductance (%Lp). Data were analyzed with one-way ANOVA and Tukey tests (α=0.05). RESULTS The toothpastes calcium silicate + sodium phosphate and potassium nitrate, showed significant decrease in %Lp, with no difference between them. The regular fluoridated toothpaste also decreased the %Lp, not differing from potassium nitrate. No desensitizing toothpaste showed change in %Lp. Human saliva, oligopeptide-104 and stannous chloride + chitosan presented significant increase in %Lp, without difference between them. CONCLUSION Calcium silicate + sodium phosphate, potassium nitrate, and the regular fluoridated toothpaste decreased dentine permeability, whereas the desensitizing toothpastes tested did not. CLINICAL RELEVANCE Toothpastes had distinct impacts on dentine permeability, which may reflect a variable effect on the treatment of dentine hypersensitivity. Within the limitations of a laboratory-based study, toothpastes with an anti-erosive claim could also be effective in reducing the pain in dentine hypersensitivity

Effectiveness and acid/tooth brushing resistance of in-office desensitizing treatments—A hydraulic conductance study

Objective To evaluate dentin permeability and tubule occlusion of in-office desensitizing treatments, and to analyze their resistance to erosive/abrasive challenges. Design Ninety-one 1mm-thick dentin discs were immersed in EDTA solution for 5 min. After analyzing the maximum dentin permeability, the specimens were randomly allocated into 7 experimental groups (n = 10): Control (no treatment); Er,Cr:YSGG laser; Nd:YAG laser; Gluma Desensitizer; Duraphat; Pro-Argin toothpaste; Calcium Sodium Phosphosilicate (CSP) paste. The post-treatment permeability was assessed and then the specimens were subjected to a 5-day erosion-abrasion cycling protocol: 4x/day of immersion in citric acid solution (5 min;0.3%), followed by exposure to clarified human saliva (60 min). After the first and last acid challenges, specimens were brushed for 15 s, with exposure to the toothpaste slurry for total time of 2 min. Dentin permeability was re-measured (post-cycling). Percentage of dentin permeability for each experimental time was calculated in relation to the maximum permeability (%Lp). Data were analyzed with 2-way repeated measures ANOVA and Tukey tests (α = 0.05). Surface modifications were analyzed by scanning electron microscopy. Results In both experimental time CSP paste and Gluma Desensitizer did not differ from each other (p = 0.0874), and were the only groups that presented significantly lower %Lp than the Control (p = 0.026 and p = 0.022, respectively). After treatment, they were able to reduce dentin permeability in 82% and 72%, respectively. The %Lp post-cycling was higher than post-treatment value for all groups (p = 0.008). Dentin permeability increased 21% for CSP paste and 12% for Gluma, but they remained significant different from Control. Deposits on the surface were observed for CSP paste; and for Gluma, tubule diameters were shown to be smaller. Conclusions CSP paste and Gluma Desensitizer were the only treatments able to decrease dentin permeability post-treatment and to sustain low permeability post-cycling

Toothpaste factors related to dentine tubule occlusion and dentine protection against erosion and abrasion.

OBJECTIVES To investigate the effect of toothpastes on dentine surface loss and tubule occlusion, and the association of toothpaste-related factors to each of the outcomes. MATERIALS AND METHODS One hundred and sixty human dentine specimens were randomly distributed into 10 groups, according to different toothpastes. The specimens were submitted to artificial saliva (60 min), citric acid (3 min), and brushing abrasion (25 s; totalizing 2 min in toothpaste slurries). This was repeated five times and two outcome variables were analyzed: dentine surface loss (dSL; μm) and tubule occlusion by measurement of the total area of open tubules (Area-OT; μm2). Data were analyzed with Kruskal-Wallis and Mann-Whitney tests (α = 0.05); bivariate and multivariate regressions were used to model the association of the chemical (pH, concentration of F-, Ca2+, and PO43- and presence of Sn2+) and physical (% weight of solid particles, particle size, and wettability) factors of the toothpastes to both outcome variables. RESULTS Toothpastes caused different degrees of dSL and did not differ in Area-OT. All chemical and physical factors, except the presence of Sn2+, were associated with dSL (p < 0.001). Area-OT was associated only with the presence of Sn2+ (p = 0.033). CONCLUSION Greater dSL was associated with lower pH, lower concentration of F-, higher concentration of Ca2+ and PO43-, greater % weight of solid particles, smaller particle size, and lesser wettability, whereas tubule occlusion was associated with the presence of Sn2+. CLINICAL RELEVANCE Depending on their chemical and physical composition, toothpastes will cause different degrees of dentine tubule occlusion and dentine surface loss. This could, in turn, modulate dentine hypersensitivity