Glass fiber posts (GFP) have an elastic modulus that shares structural characteristics with dentin. Ineffective removal of the smear layer (SL) in the root canal after post space preparation reduces resin tag formation, compromising an efficient hybrid layer formation leading to a subsequent debonding. In this sense, this review article focuses on the published literature related to dentin conditioning for GFP placement with the use of acidic solutions such as EDTA, citric and maleic acid or prefabricated conditioning solutions such as MTAD and QMix, both with/without activation by sonic or laser devices, analyzed by scanning electron microscopy (SEM) and/or push- out bond strength (POBS) test. The collected information suggested that the conditioning agent that showed better results for dentin conditioning increasing the bond strength of the GFP to the root canal is 17% EDTA without activation.

This study aimed to evaluate if the change of vehicle for CTZ (Chloramphenicol, Tetracycline, zinc oxide, and Eugenol) paste improves the inhibition of Enterococcus faecalis in vitro. The vehicles evaluated alone and mixed with CTZ were Eugenol, propylene glycol (PG), super-oxidized solution (SOS), grapefruit-seed extract (GSE), and 0.9% saline solution as a negative control. A clinical isolate of E. faecalis was morphologically and biochemically characterized, and its antimicrobial susceptibility was tested using 20 antimicrobial agents. Once characterized, the clinical isolate was cultivated to perform the Kirby–Bauer disc diffusion method with paper discs embedded with the different vehicles mixed or used alone, and incubated at 37 °C for 24 h. Data were analyzed using one-way ANOVA, and the means were compared using Tukey test with a significance level of p < 0.05. For vehicles used alone, GSE presented the greatest inhibition showing a statistically significant difference with the rest of the vehicles. When vehicles were mixed with the CTZ paste, PG showed a greater inhibition with a statistically significant difference from the rest of the vehicles. In conclusion, the vehicle used to mix the CTZ paste plays an important role in the inhibition of E. faecalis in vitro; therefore, we consider that this can be an important factor to achieve success in the use of this technique.

Introduction: Root dentin is a porous and complex dental surface that may have irregularities and deposits of organic material. To achieve an effective bond between restorative materials and root dentin, it is necessary that the restorative materials adhere intimately to the dentin surface. Metalloproteinases (MMPs) are a group of proteolytic enzymes that perform an important role in degrading the extracellular matrix and remodeling connective tissue. The aim of this research was to determine the scientific evidence available on the role played by MMPs in adhesion to root dentin and their putative inhibitors. Materials and Methods: Several techniques have been used to evaluate the presence of MMPs in the root dentin of human and bovine teeth, such as Western blot, immunohistochemistry, immunofluorescence, and zymography, the latter also being used together with the EnzCheck assay to evaluate the inhibitory effect of adhesion protocols on the activity of root MMPs in vitro. Results: When analyzing the databases, 236 articles were found, 12 of which met the selection criteria. The variables analyzed were articles that evaluated different MMP inhibitors in root dentin. Conclusions: In the adhesion to radicular dentin, MMPs have a crucial role in the degradation of the extracellular matrix of dentin and the remodeling of the dentin surface because excessive MMP activity can be harmful to dental health, since excessive degradation of the extracellular matrix of dentin can weaken the tooth structure and decrease fracture resistance. Therefore, it is important to monitor MMP activity during root dentin bonding procedures.

Mechanical vibrations have a biphasic effect depending on the context in which they are applied; their anabolic action has been used in medicine to increase bone density. In dental specialties such as orthodontics, their catabolic effect during mechanical compression has been widely studied, but the anabolic effect of vibrations is less investigated, so it is important to carry out research to clarify the effect of vibrations on the alveolar bone, explore a new approach to its use in orthodontics, and the increase of post-treatment bone density to prevent relapse. Hence, this work aims to systematically review the literature to evaluate the evidence regarding vibratory stimulation and its anabolic effects on alveolar bone in animal models. Methodology: A systematic review followed the PRISMA guidelines in PubMed, Scopus, and Web of Science databases. With the PICO strategy, we formulate the subsequent research question: Does the application of vibrational force induce an anabolic effect in the alveolar bone of animal models? Due to the lack of human studies, the population of interest was animal models; only articles where mechanical vibrations were the intervention method and the alveolar bone density or osteogenesis were evaluated and included. The selected studies underwent quality and risk of bias assessment through ARRIVE and SYCRLE instruments, respectively. This protocol was registered in INPLASY, under ID number: 202280103. Results: All eight articles included in this work demonstrate that applying low and high frequency vibrations increases the osteogenic effect by increasing the density and volume of bone tissue and increasing the expression of osteogenic markers. The included studies present a medium quality and risk of bias. Conclusion: It is important to highlight that, regardless of the protocol used, low or high frequency vibrations increase bone density, particularly in the alveolar bone, since this is the bone of interest in orthodontics. These promising results set an important precedent for the design of experimental protocols but now in the context of post-orthodontic treatment in humans.

This study aimed to evaluate if the change of vehicle for CTZ (chloramphenicol, tetracycline, zinc oxide, and eugenol) paste improves the inhibition of Enterococcus faecalis in vitro. The vehicles evaluated alone and mixed with CTZ were eugenol, propylene glycol (PG), chitosan, su-per-oxidized solution (SOS), grapefruit-seed extract (GSE), and as a negative control, 0.9% saline solution. A clinical isolated of E. faecalis was morphological and biochemical characterized, in-cluding antimicrobial susceptibility was tested using 20 antimicrobial agents. Once character-ized, the clinical isolated was cultivated to performed Kirby–Bauer disc diffusion method with paper discs embedded with the different vehicles mixed or used alone, incubating at 37 ºC for 24 h. Data were analyzed by One-way ANOVA and the means were compared using Tukey test with a significance level of p<0.05. For vehicles used alone, GSE presented the greatest inhibition showing a statistically significant difference with the rest of the vehicles. When vehicles were mixed with the CTZ paste, PG showed a greater inhibition with a statistically significant differ-ence from the rest of the vehicles. In conclusion, the vehicle used to mix the CTZ paste plays an im-portant role in the inhibition of E. faecalis in vitro, therefore we consider that this can be an im-portant factor to achieve success in the use of this technique.