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The materials as well as the procedures successfully used in modern restorative dentistry are based on scientific selection criteria which can predict outstanding results both in terms of physiological aspects and durability of the workmanship. The rationale of using certain materials and the success or failure to use certain techniques have contributed in time to the evolution of restorative dentistry. The optimal way of combining the material with its application and finishing technique implies an exhaustive approach to the subject that still requires the specialists’ research and concern for their improvement and development. Among the restorative materials, those that meet the patients’ aesthetic exigencies are the composite resins. In spite of all the advantages resulting from their intrinsic characteristics, it should be noted though that composite resins still have inconveniences related in the first place to the polymerization contraction/shrinkage, which causes a gap between the obturation and the dental tissue further resulting in the generation of marginal micro-infiltrations with all the related drawbacks. Knowing the behavior of the material and understanding its use in various manners can help the practitioner in its efforts to minimize undesirable effects, which is generally possible by applying compensatory clinical techniques. The aim of the experimental research is to evaluate the marginal micro-infiltrations from the class II cavity restorations with composite diacrylic resins according to the different techniques of restoration (stratification technique, flow technique and pre-photopolymerized insert technique) and the establishment of the optimal restorative technique to minimize side effects.

Low velocity impact tests were conducted on quasi-isotropic [±45/0/90o]xs laminates under drop weight impact from 0.7m, corresponding to a 30J energy. In this respect modified epoxy blends reinforced with carbon and Kevlar woven fabrics laminates were developed using autoclave technology. The four configurations developed for low velocity impact tests aimed at investigating several aspects like: the effect of fiber type, stacking sequence and mainly technological processing parameters, on the impact performances. The recorded Load-Time curves were plotted and visual inspection, high resolution laser scanner were used to observe the fracture characteristics of the impacted composite laminates. The results obtained showed that for tested configurations, both stacking sequence and processing parameters directly linked to fiber volume fraction, have a strong effect on the impact performances. The amount of absorbed energy, ductility index was calculated for each configuration under study. The results obtained showed that hybrid configuration exhibits lower stiffness and damage initiation energy amount when compared to carbon reinforced configurations. Nevertheless, their damage propagation energy amount and ductility index was the uppermost. This behaviour was already reported previously [1] and is partially attributed to the higher elastic energy absorption of carbon fibers that delays the propagation of delamination, and fiber breakage. Lower tenacity obtained on hybrid laminates was attributed to both lack of resin local rinse saturate and to the intrinsic anisotropy of para-aramid fibers.

Carbapenem antibiotics resistance is a medical threat in antibacterial therapy as the pathogen resistant strains easily evolve a multi-drug resistance action to other incurable agents. The protective transport of current antibiotic molecules using nano-carriers initiates a huge approach in the antibacterial therapy, allowing the nanohybrids to defeat all these health threat pathogen agents. Chitosan is a linear cationic polysaccharide being often used in medical area as a biocompatible encapsulating agent in antibiotic delivery nanosystems. This work refers to encapsulation of imipenem into biodegradable chitosan nanoparticles in order to destroy antibiotic-resistant bacteria and limit the microbial adhesion and multiplication. Nanoparticles were prepared by ion gelation method using tripolyphosphate as cross linking agent. The obtained hybrid nanocapsules were then characterized and evaluated as a potential nano-device to beat antimicrobial resistance.

The usual treatment for tuberculosis is difficult by its long-term therapy, raised dosing frequency and adverse effects of anti-tuberculosis drugs. Anionic clays, also called layered double hydroxides are a class of hydrotalcite like structures having high compositional variety and being able to self-assembly in the presence of drug molecules. The work refers to the development of nanohybrid materials like delivery systems that intercalates isonicotinic acid hydrazide, known as isoniazid anti-tuberculosis drug, into layered structure of hydrotalcite compounds. Loaded drug molecules of isoniazid were proved to be released in a controlled way from the as synthesized nanostructure in a simulated buffer solution. The obtained sample was characterized by advanced techniques thus demonstrating the inclusion of isoniazid antibiotic between hydrotalcite sheets. These results revealed important expectations for further researches of these organic-inorganic nanocomposites for tuberculosis treatment.

Amoxicillin and clavulanic acid are two of the most commonly prescribed antibacterial worldwide for treating oral infectious diseases. Oral health is of big importance for well-being and general health. A few novel drug delivery systems were designed for oral treatment and prophylaxis of different diseases in the oral cavity. This work focused on the latest drug delivery development of the most common oral pathologies, namely, periodontitis, oral mucosal infections, dental caries and oral cancer. Herein we reveal the synthesis, characterization and application of chitosan nanoparticles for intracellular transport of the weakly cell-penetrating amoxicillin and clavulanic acid in order to improve their efficacy on bacterial infections.

The main properties of dental adhesives should be good marginal adaptation, high retention strength and the possibility of not negatively influencing clinical sustainability. Dental adhesives are continuously improving to increase their retention to dental structures by increasing penetration in these structures, as it was shownin the in-vitro tests requiring imaging and qualitative analysis to allow the evaluation of experimental samples as well as the development of new materials. The main objective of this study is the qualitative and quantitative analysis of the layer of modified dental adhesives with ferrous nanoparticles encapsulated in a SiO2 membrane located between the surface of the dental preparation and the surface of the photopolymerizable composite filling. For qualitative and quantitative analysis of the samples, technologies such as SEM, optical microscopy and EDX were used.

Aortic aneurysm (AA) and especially dissecting aneurism (DAA) represent life threatening medical conditions and vascular reconstruction surgery with the insertion of a vascular prosthetic grafts is often required to save patients life. In this paper we debate over the long term outcome of 23 patients who underwent five to eight years ago an aortic reconstruction surgery with insertion of Dacron grafts. They attended, during 2018, the emergency room of the County Emergency Hospital Pius Brinzeu of Timisoara in terms of patency complications of the prosthesis. Despite slight dilatation of the Dacron graft and of the native aorta, presence of mural thrombi and/or progress of aortic regurgitation, their evolution was satisfactory, without severe complications.

The CAD/CAM technology has been successfully integrated in clinical and laboratory aspects of dental medicine. The present in vitro study focuses on the biochemical interactions between saliva and three types of polymeric resins for occlusal splints. Dental material samples were produced from 3D printed, milled and self-cured resins and were incubated with saliva samples from 20 healthy volunteers. The results showed that the 3D printed and milled polymeric resins did not produce any significant changes in oxidative stress parameters (uric acid, TAC, GGT, OXSR-1) or inflammatory markers (IL-2, IL-6). On the other hand, the self-cured acrylic resin produced a significant decrease in the salivary TAC and uric acid, the most important antioxidants in saliva, affecting the capacity of saliva to protect the oral environment against oxidative stress.

Secondary autogenous bone grafting is the gold standard for the closure of an alveolar cleft. A preoperative surgical planning helps to determine the optimal shape and volume of the graft, that ideally guide canine eruption to the cleft area and ensure adequate nasal support. The authors describe their experience with design and use of an individually shaped 3D template for an autologous bone graft with fibrin glue for correct volume design. The conforming template is designed using freeware and open source software, it is manufactured by means of additive technology using autoclavable resin.

This work reports the activation of polyurethane film surfaces in order to enrich them with polar groups such as -NH2, -OH, -COOH or radicals, which further allows immobilization of several bioactive compounds. UV-activation was used to introduce new groups on the polymer surface without affecting the bulk properties. The current arising species improve the wettability of the PU surfaces as it was observed from the static contact angle measurements. The structure and composition of the new PU surfaces were analyzed by using ATR-FTIR spectroscopy. The results suggested the possibility of modifying the PU surfaces in a shorter time periods, in order to provide many sites to attach other biomacromolecules by polar interaction or hydrogen bonding.