Does the use of reservoirs have any impact on the efficacy of at-home bleaching? a systematic review

Abstract To answer the following focused question through a systematic review: "Are the risk and intensity of tooth sensitivity (TS) and bleaching efficacy different between adult patients who undergo at-home bleaching using trays with reservoirs and those who use trays without reservoirs?". A comprehensive search was performed in the MEDLINE via PubMed, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database, Brazilian Library in Dentistry, Cochrane Library, and grey literature without restrictions. Abstracts from conferences; unpublished and ongoing trial registries, dissertations and theses (ProQuest Dissertations and Periódicos Capes Theses databases) were searched. Only randomized clinical trials (RCTs) were included. We used the Risk of Bias tool (RoB) from the Cochrane Collaboration for quality assessment. After the removal of duplicates, title and abstract screening and full-text examination, nine RCTs remained for qualitative analyses. The great majority of the studies did not report the method of randomization, allocation concealment, and examiner blinding during color assessment. From the nine studies, eight were at unclear risk of bias. In regard to color change, four studies reported no change and two reported improved color change with reservoirs. Only four studies recorded tooth sensitivity and they reported no significant differences. Only one study reported greater gingival irritation with reservoirs. Lack of data reporting prevented us from running a meta-analysis. Further well-designed RCT should be conducted to answer this research question. So far there is not evidence to support that reservoirs in bleaching trays improve color change. PROSPERO - CRD42016037628

Resumo Para responder a seguinte questão de pesquisa através de uma revisão sistemática: "O risco e a intensidade de sensibilidade dentária (SD) e eficácia de clareamento são diferentes entre pacientes adultos que realizam clareamento caseiro usando moldeiras com reservatórios e aqueles que usam moldeiras sem reservatórios?". Uma pesquisa abrangente foi realizada no MEDLINE via PubMed, Scopus, Web of Science, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Biblioteca Cochrane e literatura cinzenta, sem restrições. Os resumos da conferência anual da Associação Internacional para Pesquisa Dental além de estudos registrados ou em andamento também foram pesquisados. Dissertações e Teses foram pesquisados utilizando o Capes Journal Dissertações e Teses ProQuest. Apenas ensaios clínicos randomizados (ECR) foram incluídos. Usamos a ferramenta Risk of Bias (RoB) da Cochrane para avaliação de qualidade. Após a remoção de duplicatas, triagem de título e resumo e exame de texto completo, nove ECRs permaneceram para análises qualitativas. A grande maioria dos estudos não relatou o método de randomização, ocultação de alocação e cegamento do examinador durante a avaliação de cores. Dos nove estudos, oito estavam sob risco claro de viés. Em relação à mudança de cor, quatro estudos não relataram nenhuma mudança e dois relataram melhora na mudança de cor com reservatórios. Apenas quatro estudos registraram a sensibilidade dentária e não relataram diferenças significativas. Apenas um estudo relatou maior irritação gengival com reservatórios. A falta de relatórios de dados nos impediu de executar uma meta-análise. Outros ECR bem desenhados devem ser conduzidos para responder a esta questão de pesquisa. Até agora não há evidências que sustentem que reservatórios em moldeiras de clareamento melhorem a mudança de cor. PROSPERO - CRD42016037628

Effects of Amorphous Calcium Phosphate Administration on Dental Sensitivity during In-Office and At-Home Interventions.

BACKGROUND: Tooth bleaching is the most frequently employed whitening procedure in clinics. The major side effect of tooth bleaching is dental sensitivity during and after the treatment. Here, we evaluated whether the administration of amorphous calcium phosphate (ACP), during in-office and at-home procedures may impact on dental sensitivity. METHODS: Eighty patients, responding to the study requirements were enrolled according to the following criteria. Group 1 (n = 40), received in-office, 10% ACP prior to 30% professional hydrogen peroxide application. The whitening procedure continued at home using 10% carbamide peroxide with 15% ACP for 15 days. Group 2 (n = 40) received only 30% hydrogen peroxide application and continued the whitening procedures at home, using 10% carbamide hydroxide, without ACP- Casein phosphopeptides (CPP), for 15 days. Dental sensitivity was recorded with a visual analogue scale (VAS) at baseline, immediately after, and at 15 days after treatment in the two groups. RESULTS: We observed that patients receiving ACP in the bleaching mixture experienced decreased dental sensitivity (* p ≤ 0.05), as detected by VAS scale analysis immediately following the procedures. Patients receiving ACP-CPP during at-home procedures showed a statistically significant (*** p ≤ 0.0001) reduction of dental sensitivity. CONCLUSIONS: We demonstrated that ACP-CPP administration, while exerting the same whitening effects as in control subjects receiving potassium fluoride (PF), had an impact on the reduction of dental sensitivity, improving patient compliance.

Análise de citotoxicidade, desmineralização e potencial clareador de géis clareadores experimentais, baseado em peróxido de carbamida 15% adicionados de nano-hidróxiapatita / Analysis of cytotoxicity, demineralization and bleaching potential of experimental bleaching gels, based on 15% carbamide peroxide added with nanohydroxyapatite

O clareamento dental é considerado um procedimento muito seguro, de efeito rápido e agradável, tornando-se um dos procedimentos mais realizados na odontologia. Contudo, o mesmo apresenta alguns efeitos colaterais, sendo o principal deles a sensibilidade dental, que pode ser causada pela citotoxidade, pela desmineralização, pela geração de espécies reativas do oxigênio na polpa dental e pela degradação da região interprismática facilitando o estimulo nos túbulos dentinários. Diante disso, a presente pesquisa avaliou a desmineralização, a citotoxidade e o potencial clareador de géis clareadores experimentais baseados em peróxido de carbamida (PC) 15%, adicionados de 5% e 10% de nano partículas de hidroxiapatita (n-Hap). Para a avaliação cromática foram utilizados 36 incisivos bovinos divididos em 3 grupos: Grupo1 PC 15%, Grupo 2 PC 15% adicionado 5% nHap e grupo 3 PC 15% com 10% n-Hap, mensurando a cor antes e depois do procedimento terapêutico clareador com auxilio de um espectrofotômetro. As coordenadas do CIELAB foram analisadas para verificação da diferença de cor (ΔE) obtida entre os grupos e dentro do próprio grupo (L*) e, após a analise estatística, foi verificado que todos os géis foram capazes de clarear e não houve diferenças entre os grupos. A citotoxidade foi verificada através da absorbância das células viáveis após o tratamento com o MTT e 1:800 das preparações de agente clareador e gel contendo 5% e 10% de n-Hap aplicadas sobre células L929. Nesse caso os grupos foram desiguais estatisticamente, apresentando o PC 15% como o mais tóxico, seguido do PC 15% adicionado de 10% de n-Hap e o melhor resultado foi obtido pelo gel acrecido de 5% de n-Hap. A análise do conteúdo mineral foi realizada pela fluorescência de raios X por dispersão de energia, onde foi necessário o uso de 15 dentes bovinos, que tiveram seus terços médios seccionados, embutidos em resina epóxi e planificados, e foram dividos em grupos de 5 CPs. Cada CP foi aferido em 8 pontos diferentes antes e depois, nos mesmos pontos da terapia clareadora. Foi então verificado que os géis experimentais apresentaram menor perda de Ca e P. No entanto, não houve diferenças estatísticas entre os grupos 2 e 3. Diante das limitações do presente estudo in vitro é possível concluir que os géis experimentais contendo n-Hap foram eficazes em reduzir a citotoxidade e desmineralização sem perder a eficácia da terapia clareadora

Dental whitening is considered a very safe, quick and pleasant procedure, making it one of the most accomplished procedures in dentistry. However, it has some side effects, the main one being sensibility, which can be caused by cytotoxicity, demineralization, oxygen arrival in the dental pulp and the degradation of the interprismatic region facilitating the stimulation in the dentin tubes. Therefore, the present study evaluated the demineralization, cytotoxicity and bleaching potential of 15% carbamide peroxide-based (PC) based bleaching gels added with 5% and 10% nano-hydroxyapatite (n-Hap) particles. For the chromatic evaluation, 36 bovine incisors were divided into 3 groups: Group 1 PC 15%, Group 2 PC 15% added 5% nHap and group 3 PC 15% with 10% n-Hap, measuring the color before and after the the CIELAB coordinates were analyzed to verify the color difference (Δe) obtained between the groups and within the group (L *). After the statistical analysis it was verified that all the gels were able to lighten and there were no differences between the groups. Cytotoxicity was verified by optical density of viable cells after treatment with MTT and 1: 800 of the bleach and gel preparations containing 5% and 10% nHap applied in L929 cells. In this case, the groups were statistically unequal, presenting 15% PC as the most toxic, followed by PC 15% added with 10% n-Hap and the best result was obtained by the 5% n-Hap increased gel. The mineral content analysis was performed by X-ray Fluorescence by energy dispersion, where it was necessary to use 15 bovine teeth, which had their middle sections sectioned, embedded in epoxy resin and planned, and were divided into groups of 5 CPs, each CP was measured at 8 different points before and after, at the same points of the bleaching therapy, then it was verified that the experimental gels presented a lower loss of Ca and P, however there were no statistical differences between groups 2 and 3. On the face of the limitations of the present in vitro study, it is possible to conclude that the experimental gels were effective in reducing the cytotoxicity and demineralization without losing the effectiveness of the bleaching therapy.

Randomized clinical trials of dental bleaching - Compliance with the CONSORT Statement: a systematic review

Abstract We reviewed the literature to evaluate: a) The compliance of randomized clinical trials (RCTs) on bleaching with the CONSORT; and b) the risk of bias of these studies using the Cochrane Collaboration risk of bias tool (CCRT). We searched the Cochrane Library, PubMed and other electronic databases, to find RCTs focused on bleaching (or whitening). The articles were evaluated in compliance with CONSORT in a scale: 0 = no description, 1 = poor description and 2 = adequate description. Descriptive analyses of the number of studies by journal, follow-up period, country and quality assessments were performed with CCRT for assessing risk of bias in RCTs. 185 RCTs were included for assessment. More than 30% of the studies received score 0 or 1. Protocol, flow chart, allocation concealment and sample size were more critical items, as 80% of the studies scored 0. The overall CONSORT score for the included studies was 16.7 ± 5.4 points, which represents 52.2% of the maximum CONSORT score. A significant difference among journal, country and period of time was observed (p < 0.02). Only 7.6% of the studies were judged at "low" risk; 62.1% were classified as "unclear"; and 30.3% as "high" risk of bias. The adherence of RCTs evaluating bleaching materials and techniques to the CONSORT is still low with unclear/high risk of bias.

Bioactive Spheres: The Way of Treating Dentin Hypersensitivity.

Sealing exposed dental tubules is the most effective and long-term way to relieve the pain induced by dental sensitivity. A bioactive hollow sphere (strontium substituted calcium phosphate) was synthesized and added in toothpaste to study its effect on dental hypersensitivity via tooth tubules occlusion and mineralization. The size of spheres is perfect for penetrating into dental tubules, reaching to 20 µm into the tubules. The exposed dental tubules were occluded by spheres and new apatite layer after 3 days brushing. The spheres attached to the surface of dentin and the mineralized surface contained two layers, a porous layer followed by a dense apatite layer. The porous layer can be dissolved in an acidic solution, but the following dense layer could be kept even after soaking in an acid solution. In conclusion, Sr-substituted calcium phosphate spheres could be a good candidate for at-home treatment of dental hypersensitivity.