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The aim of this paper is to perform optimization of photopolymerization process of dental composites in order to obtain maximum hardness. Samples (5 mm diameter; 2, 3 and 4 mm thickness) were made of Universal Composite (UC), Bulk fill Composite (BC) and Flowable Composite (FC). Light curing of specimens was performed with 600, 1000 and 1500 mW/cm2 light intensity and an irradiation time of 20, 40 and 60 s. Vickers microhardness on the top and bottom surfaces of samples was measured. Optimization was carried out via regression analysis using QStatLab software. Photopolymerization process parameters were calculated using a specially designed MatLab software-based algorithm. For all composites, regression models for hardness on top and bottom surfaces of composite layer were established. Layer thickness as well as hardness on top and bottom surfaces of each composite was calculated for 21 curing modes varying with light intensity and irradiation time. It was established that photopolymerization guidelines only of FC manufacturer guarantee the required hardness, while recommended regimes for UC and BC did not satisfy this requirement. Tables, containing recommended light curing regimes, were developed for three composite types, guaranteeing high hardness of composite restoration. They were designed to facilitate work of dentists in dental offices.

This review examines literature data concerning the bacterial fi ndings in chronic periodontitis depending on pocket depth, and presents the latest published information on the presence of proinfl ammatory factors in periodontal environment. It has been found that chronic periodontitis affects as much as 80% of the middle-aged population; by comparison, the prevalence of aggressive periodontitis reaches up to 1-1.5%. It is accepted that this social disease is multifactorial in etiology, but the evidence in the literature suggests that the levels of specifi c Gram-negative organisms in subgingival plaque biofi lm play a major role in the initiation and progression of the disease. Of the many bacterial species inhabiting the periodontal environment, three types -Porphyromonas gingivalis (PG), Treponema denticola (TD), Tannerella forsythia (TF) -are strongly associated with the initiation and progression of periodontitis. Microbiological studies suggest that Porphyromonas gingivalis should be considered a major etiologic agent. Currently, Porphyromonas gingivalis is strongly associated with the pathogenesis of chronic periodontitis. On the other hand, the presence of Aggregatibacter actinomycetemcomitans in patients with chronic periodontitis may be related to the severity of the disease and thus modify the therapeutic plan. The increased amount of periodontal pathogens in the subgingival area can activate a cascade of defense mechanisms of the body associated with the production of factors causing infl ammation and destruction, which suggests a correlation between the bacterial fi ndings and the body response implemented by enhancing the local cytokine expression. Studies in the literature show that the presence of certain micro-organisms in the periodontal environment is associated to increased levels of proinfl ammatory cytokines in the gingival fl uid and gingival tissue. These levels have been associated with destructive tissues response. There is little evidence in the literature on the correlation of the levels of periodontal pathogens of sites with different pocket depth with periodontal disease activity defi ned by the degree of the proinfl ammatory cytokine expression such as tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6 ). РЕЗЮМЕНастоящий обзор реферирует данные в литературе в связи с бактериальной находкой при хроническом пародонтите в зависимости от глубины кармана и одновременно с этим ставит себе целью представить актуальную опубликованную информацию о присутствии проинфляматорных факторов в пародонтальной среде. Установлено, что хронический пародонтит наблюдается почти у 80% популяции среднего возраста, а данные о распространении агрессивного пародонтита -в границах 1-1.5%. Считается, что этиология этого социального заболевания мультифакторна, однако имеющиеся в литературе данные показывают, что уровни специфичных грамотрицательных микроорганизмов в сублингвальном бляшковом биофильме играют основную роль в появлении и прогрессировании заболевания. Среди многочисленных видов бактерий, пр...

In most of the patients with chronic hepatitis B and C, the disease progression to liver cirrhosis and a liver transplantation is necessary. Untreated oral diseases (including dental problems) can lead to infections and sepsis and may cause many complications in transplanted patients and a prerequisite dental evaluation is usually recommended for potential organ transplant candidates.Our aim was to determine the dental status in patients with chronic liver disease, knowing that liver transplant will be a life choices

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