Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT). Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89) and having broad food and drug administration (FDA) approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA), meta-tetra(hydroxyphenyl)chlorin (m-THPC), N-aspartyl chlorin e6 (NPe6), and precursors to endogenous protoporphyrin IX (PpIX): 1,5-aminolevulinic acid (ALA), methyl aminolevulinate (MAL), hexaminolevulinate (HAL). Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.

https://www.mdpi.com/1996-1944/6/3/817/pdf

Dye Sensitizers for Photodynamic Therapy.

Recent advances in BMP receptor signaling

Direct comparison of the bond strength results of the different test methods: A critical literature review

OBJECTIVES
Resin-based dental materials are not inert in the oral environment, and may release components, initially due to incomplete polymerization, and later due to degradation. Since there are concerns regarding potential toxicity, more precise knowledge of the actual quantity of released eluates is necessary. However, due to a great variety in analytical methodology employed in different studies and in the presentation of the results, it is still unclear to which quantities of components a patient may be exposed. The objective of this meta-analytical study was to review the literature on the short- and long-term release of components from resin-based dental materials, and to determine how much (order of magnitude) of those components may leach out in the oral cavity.


METHODS
Out of an initial set of 71 studies, 22 were included. In spite of the large statistical incertitude due to the great variety in methodology and lack of complete information (detection limits were seldom mentioned), a meta-analytical mean for the evaluated eluates was calculated. To relate the amount of potentially released material components with the size of restorations, the mean size of standard composite restorations was estimated using a 3D graphical program.


RESULTS
While the release of monomers was analyzed in many studies, that of additives, such as initiators, inhibitors and stabilizers, was seldom investigated. Significantly more components were found to be released in organic than in water-based media. Resin-based dental materials might account for the total burden of orally ingested bisphenol A, but they may release even higher amounts of monomers, such as HEMA, TEGDMA, BisGMA and UDMA. Compared to these monomers, similar or even higher amounts of additives may elute, even though composites generally only contain very small amounts of additives. A positive correlation was found between the total quantity of released eluates and the volume of extraction solution.


SIGNIFICANCE
There is a clear need for more accurate and standardized analytical research to determine the long-term release from resin-based materials. Several guidelines for standardization are proposed.

How much do resin-based dental materials release? A meta-analytical approach (vol 27 pg 723, 2011)

Statistical Methods in Agriculture and Experimental Biology.

A possibilidade de dor advinda do clareamento dental pode limitar sua indicacao, especialmente em pacientes com diagnostico de hipersensibilidade dentinaria Objetivo: Realizar uma serie de casos com alternativas de clareamento dental que visam a diminuicao da sensibilidade pos-operatoria Descricao dos casos: Tres pacientes com hipersensibilidade e queixa de escurecimento dental foram selecionados Para cada paciente foi determinada, aleatoriamente, uma tecnica de clareamento, utilizando gel a base de peroxido de hidrogenio 15 ou 35%; e dessensibilizacao previa ou posterior ao clareamento (com dentifricio ou gel de nitrato de potassio a 2%) Conclusao: Foi possivel obter sucesso no clareamento dental dos tres casos, porem, a dessensibilizacao previa com dentifricio resultou em maior conforto para o paciente

Tooth-whitening in patients with hypersensitivity: case series

This study evaluated the bonding compatibility between dual-cured resin cements and simplified adhesive systems (one-step self-etch and two-step etch & rinse), measured after 24 hours and 3 months. The occlusal dentin surfaces of 24 human third molars were exposed and flattened. Teeth were randomly assigned to 3 groups and treated with different combinations of adhesive system and resin cement [G1-Single Bond/Rely X ARC (SB/RX); G2-Excite DSC/Variolink II (EX/VR); G3-Adper Prompt/Rely X ARC (AD/RX)]. Indirect composite restorations were cemented on flattened surfaces, and sectioned to obtain multiple bonded beams for the microtensile bond strength test. The beams from each tooth were tested under tension after 24 hours and 3 months (ANOVA/ Tukey's test, alpha=5%). Failure patterns were evaluated with scanning electron microscopy. After 24h, AD/RX presented the lowest bond strength mean values. AD/RX specimens did not withstand three months storage. SB/RX and EX/VR presented similar bond strengths in both periods tested. The association AD/RX resulted in low bond strength mean values, especially after storage. Cementing indirect restorations using one-step self-etch adhesive systems and dual-cured resin cements would be clinically unreliable.

24 hours and 3-months bond strength between dual-cured resin cements and simplified adhesive systems.

Objetivo: Este estudo avaliou in vitro a durabilidade da uniao do cimento resinoso a cerâmica Y-TZP, verificando o efeito de diferentes tratamentos de superficie e da aplicacao previa do sistema adesivo na peca. Metodologia: Quarenta placas de cerâmica foram distribuidas em quatro grupos experimentais (n=10) de acordo com a combinacao entre tratamento de superficie (abrasao a ar ou irradiacao com laser de Er:YAG) e aplicacao de dois diferentes tipos de sistema adesivo (Scotchbond Multi Purpose - catalisador e Single Bond 2) sobre a peca previamente a insercao do cimento resinoso. Apos o tratamento da cerâmica, cilindros de cimento resinoso foram construidos, utilizando matrizes com 0,8x1mm (diâmetro x altura). Em cada grupo experimental, 5 corpos-de-prova foram submetidos ao ensaio de microcisalhamento apos 24h, e outros 5 corpos-de-prova foram testados apos 6 meses em armazenamento em agua. Resultados: Independentemente do adesivo e do tempo, as maiores medias foram obtidas nos grupos submetidos a abrasao a ar. Nao foram detectadas diferencas significativas entre os sistemas adesivos e nem entre os tempos. Conclusao: Pode-se concluir que a abrasao a ar e o uso do agente adesivo quimicamente ativado sobre a peca podem melhorar a uniao a zirconia.

/pdf/durabilidade-da-uniao-a-ceramica-de-zirconia-tetragonal-vus8lup5wq.pdf

Durabilidade da união à cerâmica de zircônia tetragonal policristalina contendo ítrio (y-tzp)

Purpose: This study aimed to provide guidelines about the coefficient of variation (CV) of shear (SBS) and microtensile (µTBS) bond strength to enamel and dentin. Methods: A search of the English language peer-reviewed literature was conducted using the PubMed database from 2000 to 2009. Only bond strength studies (SBS and µTBS) that have tested both enamel and dentin substrates were selected. The following information was gathered from the 103 papers selected: groups mean and standard deviation (SD), repetition number, and type of statistical analysis. The CV of each study was calculated by using its mean and SD values, the normality of shear and microtensile CV was analyzed using Shapiro-Wilk test, and a CV classification was established for each variable. Results: According to the CV classification proposed, values below 10.3% and 11.3% could be considered low for shear bond strength to enamel and dentin, respectively; and values below 15.4% to enamel and 16.4% to dentin could be considered low for the microtensile test. Values higher than 46.8% and 62.1% (shear bond strength to enamel and dentin) and 45.9% and 45.5% (microtensile bond strength to enamel and dentin) showed a very high variability. Conclusion: Such classification can be useful for future experiments on adhesive materials to estimate statistical power and data precision.

Variability of shear and microtensile bond strength tests to enamel and dentin Variabilidade de testes de cisalhamento e microtração ao esmalte e à dentina

A busca por tratamentos esteticos vem crescendo e, nesse sentido, os pacientes comparecem cada vez mais aos consultorios para obter sorriso agradavel. O objetivo deste trabalho e descrever as principais ferramentas utilizadas na execucao de planejamentos esteticos. De acordo com o estudo da literatura sobre o assunto e com a aplicacao pratica destes principios, verifica-se que fotografias, enceramentos diagnosticos e planejamentos digitais sao ferramentas indispensaveis para uma avaliacao detalhada de todos os fatores que interferem na harmonia e simetria dos elementos que compoem o sorriso, possibilitando assim, bons resultados.

/pdf/recursos-contemporaneos-do-planejamento-estetico-integrado-qzkfs660d0.pdf

Andrea Nóbrega Cavalcanti

Papers

Tooth-whitening in patients with hypersensitivity: case series

24 hours and 3-months bond strength between dual-cured resin cements and simplified adhesive systems.

Durabilidade da união à cerâmica de zircônia tetragonal policristalina contendo ítrio (y-tzp)

Variability of shear and microtensile bond strength tests to enamel and dentin Variabilidade de testes de cisalhamento e microtração ao esmalte e à dentina

Recursos contemporâneos do planejamento estético integrado