Effect of Xylitol Varnishes on the Inhibition of Demineralization in Vitro

Abstract Objective: To evaluate the efficacy of xylitol varnishes in the inhibition of enamel demineralization in vitro. Material and Methods: Bovine enamel blocks (n=120) were randomly allocated to four groups (n = 30), and the surface hardness (SH) was measured at baseline. The blocks were treated with the following varnishes: 20% xylitol, 20% xylitol plus F (5% NaF), Duraphat™ (5% NaF, positive control), and placebo (no-F/xylitol, negative control). The varnishes were applied and removed after 6 h of immersion in artificial saliva. The blocks were subjected to pH cycles (demineralization and remineralization for 2 and 22h/day, respectively, for 8 days). Surface and cross-sectional hardnesses were measured to calculate the percentage of SH loss (%SHL) and the integrated loss of the subsurface hardness (ΔKHN). Data were statistically analyzed using Kruskal-Wallis and Tukey's tests (p<0.05). Results: %SHL was significantly decreased by 20% xylitol plus F, Duraphat™, and 20% xylitol varnishes compared to placebo. The use of 20% xylitol plus F varnish led to a significantly lower percentage of SH loss compared to the use of 20% xylitol varnish without F. However, the experimental and commercial varnishes led to significantly lower subsurface demineralization compared to placebo and did not differ from each other. Conclusion: Xylitol varnishes, especially when combined with F, effectively prevent enamel demineralization (AU).

Effect of the cranberry ( Vaccinium macrocarpon ) juice on reducing dentin erosion: an in vitro study

Abstract Vaccinium macrocarpon (cranberry) is a fruit that has an inhibitory effect on matrix metalloproteinases (MMPs) present in dentin and saliva. The inhibition of MMPs has been shown to prevent dentin erosion. The aim of this study was to analyze the effect of cranberry juice on the reduction of dentin erosion in vitro. Specimens of bovine dentin (4×4×2 mm) were randomized and divided into 4 groups (n = 17/group): distilled water (C-control, pH 7.2); green tea extract solution containing 400 µm epigallo-catechin-gallate (EGCg, positive control, pH 4.5); 10% cranberry extract (CrE, pH 3.9), and cranberry juice (CrJ, Cranberry JuxxTM, pH 2.8). Specimens were submitted to erosive pH cycles for 5 days. Each day, four demineralizations were carried out with 0.1% citric acid (90 s). After the acid challenges, specimens were rinsed and kept in treatment solutions for 1 min; afterwards, they were rinsed and stored in artificial saliva for 1 h at 37°C (or overnight at the end of each day). After the experimental period of 5 days, dentin loss was evaluated by contact profilometry. Data were analyzed by ANOVA and Tukey's test (p < 0.05). Dentin loss (µm ± SD) was significantly lower for all treatments (EGCg = 9.93 ± 2.90; CrE = 12.10 ± 5.44; CrJ = 11.04 ± 5.70) compared to control (21.23 ± 11.96), but it did not significantly differ from each other. These results indicate that the commercial cranberry juice, despite its low pH, is able to reduce dentin erosion, which might be due to the ability of cranberry components to inhibit MMPs.

Effect of vegetable oils applied over acquired enamel pellicle on initial erosion

Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 - 5% and pure palm oil, respectively; GC5 and GC100 - 5% and pure coconut oil; GSa5 and GSa100 - 5% and pure safflower oil; GSu5 and GSu100 - 5% and pure sunflower oil; GO5 and GO100 - 5% and pure olive oil; CON− - Deionized Water (negative control) and CON+ - Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey's test (p<0.05). Results Enamel blocks of GP100 presented similar hardness loss to GSu100 (p>0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.

CO2 laser and/or fluoride enamel treatment against in situ/ex vivo erosive challenge

ABSTRACT Objective This in situ/ex vivo study investigated the effect of CO2 laser irradiation and acidulated phosphate fluoride gel (APF) application, separately and in combination, on enamel resistance to erosion. Material and Methods During 2 experimental 5-day crossover phases, 8 volunteers wore intraoral appliances containing bovine enamel blocks which were submitted to four groups: 1st phase - control, untreated and CO2 laser irradiation, 2nd phase - fluoride application and fluoride application before CO2 laser irradiation. Laser irradiation was performed at 10.6 µm wavelength, 5 µs pulse duration and 50 Hz frequency, with average power input and output of 2.3 W and 2.0 W, respectively (28.6 J/cm2). APF gel (1.23%F, pH 3.5) was applied on enamel surface with a microbrush and left on for 4 minutes. Then, the enamel blocks were fixed at the intraoral appliance level. The erosion was performed extraorally 4 times daily for 5 min in 150 mL of cola drink. Enamel loss was measured profilometrically after treatment and after the in situ phase. The data were tested using one-way Repeated Measures Anova and Tukey's test (p<0.05). Results CO2 laser alone (2.00±0.39 µm) did not show any significantly preventive effect against enamel erosion when compared with the control group (2.41±1.20 µm). Fluoride treated enamel, associated (1.50±0.30 µm) or not (1.47±0.63 µm) with laser irradiation, significantly differed from the control. Conclusion The APF application decreased enamel wear; however, CO2 laser irradiation did not enhance fluoride ability to reduce enamel wear.

Effect of different salivary exposure times on the rehardening of acid-softened enamel

Abstract This in situ study assessed the effect of different times of salivary exposure on the rehardening of acid-softened enamel. Bovine enamel blocks were subjected in vitro to a short-term acidic exposure by immersion in 0.05 M (pH 2.5) citric acid for 30 s, resulting in surface softening. Then, 40 selected eroded enamel blocks were randomly assigned to 10 volunteers. Intraoral palatal appliances containing 4 enamel blocks were constructed for each volunteer, who wore the appliance for 12 nonconsecutive hours: initial 30 min, followed by an additional 30, and then by an additional 1 hour. For the last additional 10 hours the appliances were used at night, during the volunteers' sleep. Surface hardness was analyzed in the same blocks at baseline, after erosion and after each period of salivary exposure, enabling percentage of surface hardness recovery calculation (%SHR). The data were tested using repeated measures ANOVA and Tukey's test (α = 0.05). Increasing periods of salivary action promoted a progressive increase in the surface hardness (p < 0.001). However a similar degree of enamel rehardening (p = 0.641) was observed between 2 hours (49.9%) and 12 hours (53.3%) of salivary exposure. Two hours of salivary exposure seems to be appropriate for partial rehardening of the softened enamel surface. The use of the intraoral appliance during sleep did not improve the enamel rehardening after erosion.

Utilização de prótese parcial fixa modificada na primeira infância: relato de caso / The use of a modified fixed partial denture in childhood:clinical case reporting

A reposição do dente decíduo perdido prematuramente é indicada para que não haja conseqüências estéticas, funcionais (fala e mastigação) e psicológicas. Crianças na primeira infância não possuem maturidade e cooperação para o uso de próteses removíveis. Assim sendo, indica-se as próteses parciais fixas modificadas. O objetivo do presente estudo é relatar o caso clínico de uma paciente de 30 meses de idade, com história de traumatismo dentário, com perda precoce do elemento 51, cujo tratamento foi a colocação de uma prótese parcial fixa modificada. A principal característica desta prótese, que a diferencia de uma prótese utilizada em adultos é a presença de conectores com o sistema tubo-barra. A estrutura metálica de um dos dentes de apoio apresenta uma barra que se encaixa em um tubo presente no pôntico, este sistema não é fixo, o que permite o distanciamento lento entre o retentor e o pôntico, através do deslocamento da barra, caso ocorra crescimento da pré-maxila. Após a moldagem dos arcos superior e inferior da paciente, a prótese parcial fixa modificada foi confeccionada com um pôntico e dois retentores de metal nos elementos 52 e 62, os quais não receberam nenhum tipo de preparo. A cimentação da prótese foi realizada com cimento resinoso dual e resina composta para um melhor resultado estético. No caso clínico descrito, pôde ser observado um resultado estético e funcional satisfatório, o que propiciou melhora na saúde bucal da paciente.

The replacement of the prematurely lost deciduous tooth is indicated to avoid aesthetic, functional (speaking and chewing) and psychological consequences. Childhood does not have maturity and cooperation to collaborate with the use of removable partial denture. Therefore, on this situation, the modified fixed partial denture can be indicated. The aim of this study is to report a case of a 30 months patient with dental trauma's history and early loss of the element 51, whose treatment was the placement of a modified fixed partial denture. The main feature of this prosthesis, which differentiates it from adults prosthesis, is the presence of connectors with the tube-bar system. The steel structure of the supporting tooth has a bar that fits into a tube present in the pontic. This system is not fixed, allowing the slow displacement between the pontic and the bar, in case of premaxilla growths. After molding the upper and lower arches of the patient, the modified fixed partial denture was fabricated with a pontic and metal on the elements 52 and 62, which did not have any kind of preparation. Prosthesis cementation was performed with dual-resin cement and composite resin for a better aesthetic result. In the described clinical case, it was found a satisfactory functional and aesthetic result, which improved patient's oral health.

Utilização de gel de papaína associado à técnica de restauração atraumática em bebê: relato de caso clínico / The use of papain gel associated with the atraumatic restorative treatment in childhood: clinical case reporting

O tratamento odontológico curativo em bebês apresenta dificuldades que podem ser diminuídas por meio da utilização do método de remoção químico-mecânico da cárie, da necessidade da utilização de anestesia e de instrumentos rotatórios. O objetivo do presente estudo é relatar o caso clínico de um paciente de 27 meses de idade, submetido à remoção químico-mecânica do tecido cariado na oclusal do elemento 85 que apresentava lesão cariosa de profundidade média. O procedimento clínico restaurador foi realizado, utilizando-se o método químico-mecânico de remoção da cárie à base de gel de papaína (Papacarie®) e posterior restauração com cimento de ionômero de vidro por meio da técnica de restauração atraumática. Foram necessárias 6 aplicações de 1 minuto e 30 segundos do gel, sem anestesia, e foi preciso utilizar-se da alta rotação para acesso à cavidade, o que resultou em piora de comportamento. No caso clínico apresentado, a aplicação do gel de papaína associada à técnica de restauração atraumática se apresentou como uma boa alternativa para o tratamento restaurador em bebê, pois diminuiu o desconforto da criança, refletindo, positivamente, no comportamento. Por outro lado, foi necessário um longo tempo clínico, e a utilização de instrumentos rotatórios para acesso à cavidade interferiu negativamente no comportamento.

The childhood restorative dental treatment presents difficulties, which can be diminished by the use of chemomechanical caries removal method by reducing the use of anesthesia and rotatory instruments. The aim of this study is to report the clinical case of a 27 months patient subjected to chemomechanical caries removal method of 85 tooth 85, which presented medium lesion depth. The procedure was performed using papain gel chemomechanical caries removal method (Papacarie ®) and the cavities were restored using the atraumatic restorative treatment, with glass ionomer cement. It took 6 applications of 1 minute and 30 seconds of gel, without need for anesthesia. However the use of rotatory instruments was necessary for cavity assessment resulting in worst child behavior. Taking into consideration the presented clinical case the application of papain gel associated with atraumatic restorative treatment seems to be a good alternative for childhood restorative treatment, since children's discomfort decreased, resulting in positive behavior. On the other hand it took a long clinical time and the use of rotatory instruments was necessary for cavity access and these factors seem to negatively interfere on child's behavior.