The aim of this research has been to develop a new generation of eco-friendly binders, soluble at alkaline pH, which could allow facile recovery of explosive fillers without using organic solvents, while maintaining their chemical and physical characteristics. For this purpose, “smart” polymeric binders are to be designed based on acrylic acid and other acrylic monomers. In this view, theoretical and experimental studies have been performed in order to establish which synthesized polymer is adequate for the desired application.
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Present study examines, by means of finite element method, the influence of cervical cavity shape on tensions distribution caused by occlusal overload of the teeth with abfraction lesion. Same force values are applied to four 3-D lower premolar finite element models, representing four different cavity shapes. An extracted lower premolar which presented an abfraction lesion has been used. The restoration was achieved by using ER adhesive systems and Giomers. The premolar was scanned and the resulting sections were processed and converted into a 3D digital format. Thus, a model of finite elements which presented a restored wedge-shaped cavity in the cervical dental area was obtained. Then, by modifying the shape and dimensions, there were created another 3 modified-shape cavities. Forces of different magnitudes (45-150N), exerted at a 45 degree angle on buccal cusp, have been applied. A wedge-shaped cavity with a short occlusal side does not show tension in the cervical region, nor in the distal angle of the restoration up to a force of 100N. So, in order to increase the retention of the abfraction restoration, changing the shape of the cavity could be the treatment of choice. Clinical relevance In order to avoid costly and unethical research, by means of FEM, different shapes of cervical cavities were easily created and conditions that influence retention of abfraction restoration were tested.
Plastic materials are widely used today in Paedodontics and Orthodontics for manufacturing preventive and therapeutic devices. Since these are worn for long times in the oral cavity biofilm forms on the smooth acrylic surfaces of those appliances. The biofilm must be removed not to destroy the oral microbiology. The aim of this study was to research the possibility of removing the microbial biofilm and disinfecting retainers using the photodynamic effect of toluidine blue O, Fotosan System (CMS Dental, Copenhagen, Denmark) in comparison to two products available on the market Corega Denture Cleanser Tablets (GlaxoSmithKline) and the Retainer Brite® Cleaning Tablets (DENTSPLY International Raintree Essix, FL, USA). The plastic material used in this experiment was the cold-cure acrylic Palapress® vario (Heraeus-Kulzer GmbH, Hanau, Germany). Images of the biofilm formed by Streptococcus pyogenes were obtained using a confocal laser scanning m icroscope. The images were analyzed using Comstat 2 software. The results showed that all the three investigated methods had a disinfectant effect. Corega Denture Cleanser Tablets reduced most of the biofilm formed on the plastic substrate.
The usage of prosthetic devices in the surgery of parietal defect is, nowadays, essential for a good abdominal wall recovery and prevention of the hernia recurrence. A good and suitable textile allograft should poses one or more, ideally all, of the following characteristics: pliable, strong, non-allergenic and with perfect tissue integration behavior. The aim of this paper is to evaluate the immediate and long term tissue reaction of different textile allografts used in open surgery of inguinal hernia repair.
Because endodontic pathology is caused due to bacterial contamination of the root canal system, endodontic treatment should focus on eliminating microorganisms in root canals. For more than 70 years Calcium Hydroxide has an important role in antimicrobial endodontic therapy. The use of calcium hydroxide is limited by the incomplete removal thereof, a residue covering 20% to 45% of the ductal wall, even after irrigation with NaOCl or EDTA. This study aims to evaluate the removal of calcium hydroxide in root canals using two different techniques.
The present paper was aimed at achieving a study on carbon nanotubes-reinforced composites and involved obtaining and characterization of composites based on epoxy compounds modified with hydroxyl groups-containing compounds (glycols). In order to obtain high flexibility epoxy resins-based composites, carboxyl- functionalized MWCNTs were used as filler at a concentration of 0.5 %. The influence of the weight concentration in CNTs on the mechanical and thermo -mechanical properties of the epoxy compounds was evaluated in comparison to mechanical properties of the DGEBA standard composites reinforced with 0.5 % MWCNT.
Sealing the pits and fissures of posterior teeth represents a local and specific method of caries prevention. The aim of this study was to evaluate the adhesion of two materials used in sealing pits and fissures: Pitt and Fisure and Fissurit FX (Voco), with the help of the scanning electronic microscope (SEM). The results of the study revealed a much higher quality of the Fissurit FX (Voco) product both in terms of adhesion to the enamel and material homogeneity. The Pitt and Fisure product showed a high degree of detachment from the enamel, marginal infiltration, large particles and a high concentration of inorganic particles.
Gestational diabetes mellitus (GDM), defined by the occurrence or discovery of glucose intolerance during pregnancy is associated with higher risk of perinatal complications and long-term development of chronic diseases both in the mother and her child. Recent data suggest that women diagnosed earlier in pregnancy, even having more risk factors, develop fewer complications. The aim of the current study is to analyse biochemical markers that play a role in the pathophysiology of GDM and could lead to an early diagnosis. The authors performed a case-control study on 50 pregnant women that finally developed GDM and 50 pregnant women with risk factors for GDM which did non develop the disease. In all cases there were monitored a series of biochemical markers like glycated haemoglobin (HbA1c), sex hormone binding globulin (SHBG), magnesium (Mg), C-reactive protein (CRP), plasma insulin level, and pregnancy-associated plasma protein A (PAPP-A). All these factors were statistically analysed using univariate and multivariate tests in order to evaluate their predicting value. The combination of traditional risk factors with HBA1c, SHBG, PAPP-A and CRP proved significant prognosis value (75% sensitivity rate, 9% false positive rate) for GDM. In conclusion, these four biochemical markers available in early pregnancy have improved the performance of predicting models concerning the development of severe GDM needing insulin treatment and predisposing to maternal and foetal complications.
The aim of this study was to determine the incidence of hypoandrogenenic to male patients with S.Met., in the context of cardiovascular risk factors. It performed description of a correlation with diagnostic components of S.Met., and specifying an interrelated male hypogonadism with each of the major cardiovascular risk factors.
The aim of this study was to evaluate shear bond strength and adhesive remnant index between two different brands of adhesive systems and brackets. The adhesive systems were represented by Opal Bond MV Composite and Opal Seal (Ultradent), respectively the fluoride releasing Transbond light cure adhesive paste and Transbond XT (3M). The utilised brackets were Avex metal bracket system (Ultradent), respectively Unitek™ Miniature Twin Metal Brackets (3M). The study was realized on 4 groups of extracted teeth: the first and second groups by using the products of the manufacturer Ultradent, respectively 3M, and the third and fourth groups by using the adhesive system of one manufacturer and the brackets of the other manufacturer. The study revealed that the use of adhesive system and brackets of the same manufacturer may increase the shear bond strength and decrease the adhesive remnant index.