Chemical analysis of n-propyl gallate used as pre-treatment for resin-dentin bond strength: In vitro study.

This study aimed to evaluate the effect of n-propyl gallate as pre-treatment for resin-dentin bond strength. The dentin pre-treatments evaluated included propyl gallate of concentrations 0.1% (w/v), 1.0% (w/v), and 10.0% (w/v), as well as glutaraldehyde 5.0% (v/v), and distilled water as a control treatment. Dentin specimens were prepared for Fourier Transformed Infrared Spectroscopy (FT-IR) (n = 3/pre-treatment). Pre-treatments were actively applied to dentin blocks before performing the adhesive procedure to composite resin. Microtensile bond strength to dentin (µTBS) (n = 8/pre-treatment) was determined after 24 h and 6 months of storage. Data were submitted to a two-way ANOVA, followed by Tukey's post hoc test. As for FT-IR, propyl gallate 1%-treated specimens presented higher water, carbonate, collagen, and amide absorbance rates compared to other tested groups, while specimens pre-treated with glutaraldehyde and distilled water presented similar absorbance curves. Regarding µTBS, all concentrations of propyl gallate resulted in statistically significant higher bond strength values than distilled water at 24 h. After 6 months of storage, propyl gallate 0.1% was the only group that maintained µTBS over time. Propyl gallate 0.1% might be a suitable dentinal pre-treatment due to being able to present chemical bonds with demineralized dentin and providing resin-dentin bond stability after 6 months of storage.

Controlled release devices as adjuvants in nonsurgical periodontal therapy: A systematic review.

Controlled release devices (CRD) have been widely studied regarding their application in periodontal therapy. Therefore, the present study aims to evaluate the use and effectiveness of controlled-release devices in nonsurgical periodontal therapy through a systematic review. The research was carried out in six different databases, namely: Online Medical Literature Search and Analysis System (Medline-PubMed), Web of Science, Science Direct, Scopus, Scielo, and Google Scholar. The descriptors "Delayed-Action Preparation," "Therapeutics," and "Periodontitis," were used with their EntryTerms and connected through the Boolean operators AND and OR. A total of 2847 studies were found, and after applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist flowchart, 34 were selected using the eligibility criteria. After that, the qualitative results were tabulated and the risk of bias in each of them was evaluated. It can be observed that the use of CRD presents itself as a successful alternative for adjuvant treatment to periodontal therapy, a fact due to its availability and local concentration in the crevicular fluid. However, further clinical research is still needed to develop devices that are effective, with an easy and quick application, as well as available at a good cost-benefit ratio.

Ácido tânico como agente biomodificador de dentina / Tanic acid as biomodificator of collagen dentin

Introdução: a utilização de diferentes polifenóis no aumento das propriedades mecânicas do colágeno dentinário tem sido bastante empregada, sendo o ácido tânico um polifenol com propriedade biológica bastante pronunciada. Objetivo: avaliar o potencial biomodificador do ácido tânico (AT) em diferentes concentrações em colágeno dentinário. Métodos: os fatores sob investigação foram módulo de elasticidade, mensurado por meio de um ensaio de flexão de três pontos (n=10) e variação de massa (n=10), aferidos com uma balança de precisão, sendo, para tanto, avaliados os seguintes elementos: ácido tânico (0,1; 1 e 10%), proantocianidina (6,5%) e água destilada (controle). Resultados: quanto ao módulo de elasticidade, os grupos tratados com ácido tânico apresentaram valores, estatisticamente, superiores (p<0,05) aos demais grupos, não sendo observadas diferenças entre suas diferentes concentrações. Para os valores de variação de massa, os grupos que foram imersos em agentes biomodificadores apresentaram valores estatisticamente (p<0,05) superiores ao grupo controle. Conclusão: o ácido tânico se apresenta como um potencial agente biomodificador do colágeno dentinário, independente da concentração utilizada, aumentando o seu módulo de elasticidade e gerando um ganho de massa após uma hora de imersão.

Introduction: The use of different polyphenols in the increase of the mechanical properties of dentin collagen has been widely used, thus, tannic acid being a polyphenol with very pronounced biological proprieties. Objective: to evaluate the biomodifying potential of tannic acid (AT) in different concentrations in dentin collagen. Methods: the factors under investigation were modulus of elasticity, measured by a three-point bending test (n = 10), and mass variation (n = 10), measured by means of a precision scale, being the following substances evaluated: tannic acid (0.1, 1 and 10%), proanthocyanidin (6.5%) and distilled water (control). Results: As for the modulus of elasticity, the groups treated with tannic acid presented statistically higher values (p <0.05) in relation to the other groups, and no differences were observed between the different concentrations. For the values of mass variation, the groups that were immersed in biomodifiers showed statistically (p <0.05) values higher than the control group. Conclusion: tannic acid presents as a potential biomodifying agent of dentin collagen, regardless of the concentration used, increasing its modulus of elasticity and generating a mass gain after one hour of immersion.