Liposomes, due to their various forms, require further exploration. These structures can deliver both hydrophilic and hydrophobic drugs for cancer, antibacterial, antifungal, immunomodulation, diagnostics, ophtalmica, vaccines, enzymes and genetic elements. Preparation of liposomes results in different properties for these systems. In addition, based on preparation methods, liposomes types can be unilamellar, multilamellar and giant unilamellar; however, there are many factors and difficulties that affect the development of liposome drug delivery structure. In the present review, we discuss some problems that impact drug delivery by liposomes. In addition, we discuss a new generation of liposomes, which is utilized for decreasing the limitation of the conventional liposomes.

Introduction: Enamel subsurface lesions or white spot lesions (WSLs) are commonly found in orthodontic patients with a prevalence of 5% to 97%. Aim: This systematic review aimed to evaluate the efficacy of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) for prevention and remineralization of WSLs in orthodontic patients in human randomized controlled clinical trials (RCTs). Methods: Relevant articles were retrieved by searching the Web of Science, Scopus, PubMed, and Cochrane Library databases up to November 2018 with no language or date restriction. The collected data included examination method, groups included in each study with number of patients in each group, study design, follow-up period and summary of important findings of each study. The risk of bias of each study was assessed according to the guidelines of the Cochrane Collaboration's tool. Results: Of 213 articles retrieved, 13 RCTs were included in this systematic review (none of them were included in the meta-analysis). Three articles showed superior efficacy of CPP-ACP for remineralization of WSLs while four studies reported the superior clinical efficacy of CPP-ACPF for this purpose. Conclusion: Both CPP-ACP and CPP-ACPF can decrease the prevalence and increase the remineralization of WSLs during/after orthodontic treatment.

Nanodentistry is an emerging field of nanotechnology in order to improvement dental treatment, care and prevention of oral diseases.

As high as 20% of the population is thought to have recurrent aphthous stomatitis (RAS), hence, finding new therapeutic agents may be needed. Pomegranate (Punica granatum), has been extensively used in the folk medicine of many cultures, as it possesses antioxidant, anti-inflammatory and anti-bacterial properties. In this study, it is hypothesized that a topical form of pomegranate peel extract (PPE) may shorten the duration, accelerate the healing and reduce the pain of RAS patients. The presented randomized, double-blind study was conducted on 56 patients. Herein, 28 patients were advised to apply PPE gel, and the other 28 patients were given placebo gel, twice daily for one week. Efficacy evaluations were made at days 0 (before using the gel), 3, 5 and 7. The mean values of ulcer size, pain and healing duration of ulcers were compared in both groups. PPE gel was significantly effective in reducing the pain (p<0.001), ulcer size (p<0.001), and healing duration of ulcers (p<0.001) over a period of one week. PPE in the form of oral gel can be used in the management of aphthous ulcers.

Increased antibiotic resistance of microorganisms as well as the need to reduce health-care costs necessitates the production of new antimicrobials at lower costs. For this reason, this study was aimed to optimize the synthesis of magnesium oxide nanoparticles with the greatest antibacterial activity. In this study, 9 experiments containing different proportions of the factors (magnesium nitrate, NaOH, and stirring time) effective in the synthesis of magnesium oxide nanoparticles were designed using the Taguchi method. Magnesium oxide nanoparticles were synthesized using the coprecipitation method, and their antibacterial activity was evaluated using colony-forming unit (CFU) and disk diffusion. Morphology, crystalline structure, and size of synthesized nanoparticles were investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM). The optimum conditions (0.2 M magnesium nitrate, 2 M NaOH, and 90 min stirring time) for the synthesis of magnesium oxide nanoparticles with the greatest antibacterial activity were determined using the Taguchi method. The results of colony-forming unit and disk diffusion revealed the optimal antibacterial activity of synthesized nanoparticles against Staphylococcus aureus and Escherichia coli bacteria. The results obtained from FTIR and XRD analyses confirmed the synthesis of nanoparticles with favorable conditions. Also, according to the SEM image, the average size of synthesized nanoparticles was determined to be about 21 nm. According to the results, magnesium oxide nanoparticles can significantly reduce the number of Gram-positive and Gram-negative bacteria and can be used as an appropriate alternative to commonly used antibacterial compounds in order to tackle drug resistance among pathogens.

Nanotechnology has been widely exploited in recent years in various applications. Different sectors of medicine and treatment have also focused on the use of nanoproducts. One of the areas of interest in the treatment measures is the interaction between nanomaterials and immune system components. Engineered nanomaterials can stimulate the inhibition or enhancement of immune responses and prevent the detection ability of the immune system. Changes in immune function, in addition to the benefits, may also lead to some damage. Therefore, adequate assessment of the novel nanomaterials seems to be necessary before practical use in treatment. However, there is little information on the toxicological and biological effects of nanomaterials, especially on the potential ways of contacting and handling nanomaterials in the body and the body response to these materials. Extensive variation and different properties of nanomaterials have made it much more difficult to access their toxicological effects to the present. The present study aims to raise knowledge about the potential benefits and risks of using the nanomaterials on the immune system to design and safely employ these compounds in therapeutic purposes.

AIM: With the increased bacterial resistance and the resulting problems in recent years, it seems necessary to find new biocompatible compounds to confront this problem. This research was conducted to optimise the synthesis of cobalt oxide nanoparticles with the highest antibacterial activity. METHODS: In the present study, 9 experiments were designed using the Taguchi method. The effect of three factors of cobalt nitrate, KOH and the stirring time in the synthesis of cobalt oxide nanoparticles with the highest antibacterial activity was investigated. The bactericidal effect of synthesised nanoparticles was evaluated using the colony-forming unit (CFU) and disk diffusion methods. The characteristics of nanoparticles were studied using the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and the scanning electron microscopy (SEM). RESULTS: The results indicated that all three evaluated factors were effective on the antibacterial properties of the synthesised nanoparticles. The best antibacterial activity of cobalt oxide nanoparticles was observed in experiment 9 (cobalt nitrate 0.6 M, KOH 2M and stirring time 60 min). The study of nanoparticles synthesised by FTIR, XRD, and SEM confirmed the formation of cobalt oxide nanoparticles with size (24 nm) and a proper structure (spinel structure). CONCLUSION: Due to the optimal antibacterial properties of the synthesised cobalt oxide nanoparticles, they can be used in the fabrication of dental and medical equipment with antibacterial properties.

No abstract