Effect of polyols and selected dental materials on the ability to create a cariogenic biofilm : on children caries-associated "Streptococcus Mutans" isolates

Secondary caries is a disease associated with the formation of biofilm on the border of the tooth and dental filling. Its development is strongly influenced by the dietary sweet foods and the type of dental material. The aim of the study was to assess the effect of sweeteners on the ability of clinical Streptococcus mutans strains to form biofilm on dental materials. Strains were isolated from plaque samples from 40 pediatric patients from the 3–6 ICADS II group. The ability to form biofilm was tested on composite and glass ionomer dental materials used for milk teeth filling in the presence of sucrose, xylitol, sorbitol, and erythritol. The bacterial film mass after 12, 24, 48, and 72 h and the number of bacterial colonies significantly decreased (p < 0.01) compared to the initial value for 5% erythritol and sorbitol on examined materials. A greater inhibitory effect was noted for glass ionomers compared to composites. Sucrose and xylitol supported biofilm formation, while erythritol had the best inhibitory effect. The use of fluoride-releasing glass ionomers exerted an effect synergistic to erythritol, i.e., inhibited plaque formation and the amount of cariogenic S. mutans. Selection of proper type of dental material together with replacing sucrose with polyols can significantly decrease risk of secondary caries development. Erithritol in combination with glass ionomer seems to be the most effective in secondary caries prevention

Lactoperoxidase as salivary defense system against dental caries - analysis of circadian rhytm, in physiological conditions and in caries.

Bakteriobójcze właściwości śliny są uwarunkowane obecnością wielu substancji związanych z odpornością wrodzoną. Jednym z tych składników jest laktoperoksydaza (LPO), która wykorzystuje nadtlenek wodoru (H2O2) i jony tiocyjanianowe (SCN-) do produkcji biobójczego utleniacza w stosunku do szerokiego spektrum drobnoustrojów. Enzym ten w obecności substratów cyklu halogenacji może prowadzić do powstania jonów hypotiocyjanianowych OSCN-, które dzięki zdolności do utleniania grup tiolowych białek drobnoustrojów zapewnia długotrwałą ochronę przed chorobami w tym m.in. próchnicą zębów. Właściwe zrozumienie działania systemu laktoperoksydazowego może pomóc opracować nowatorskie metody jednoczesnego leczenia zapalenia, i zapobiegania chorobom takim jak próchnica zębów.Celem pracy było zweryfikowanie hipotezy badawczej mówiącej, że dzieci z próchnicą zębów mają zmienioną aktywność laktoperoksydazy ślinowej względem grupy kontrolnej. Ponadto zbadano czy wydzielanie laktoperoksydazy ślinowej jest zależne od cyklu dobowego oraz sposobu pobierania śliny jako materiału diagnostycznego (ślina niestymulowana i stymulowana).Oznaczenie aktywności LPO prowadzono metodą fluorymetryczną z 2’,7’-dichlorofluorescyną jako substratem. Wyniki prowadzonych badań wskazały na silny związek (r=0,839) aktywności laktoperoksydazy w zależności od sposobu pobierania materiału. Ponadto analiza aktywność LPO związana była z rytmem dnia i nocy (największą aktywność LPO zanotowano w godzinach porannych i nocnych). Nie wykazano istotnych statystycznie różnic (p=0.9619, test t-studenta) w aktywności laktoperoksydazy w ślinie między grupą dzieci z próchnicą a kontrolą. Prowadzone badania, choć nie rozstrzygają ostatecznie podjętego problemu, wskazują że przy tak niewielkiej liczebności grupy badanej i kontroli aktywność laktoperoksydazy się nie zmienia.Antimicrobial properties of saliva originate from its innate immunity related substances. One of them is lactoperoxidase (LPO) wchich in the presence of hydrogen peroxide (H2O2) and thiocyanate ions (SCN-) produces strong oxidant effective against wide spectrum of microorganisms. In presence of halogenations cycle substrates, this enzyme produces hypothiocyanate ions OSCN- whih are capable of oxidizing protein thiol moyetes. This action results in extended protection against diseases including inter alia caries. Understanding of lactoperoxidase system mode of action could be helpful in creating innovative methods of inflamation treatment and prevention of diseases such as dental caries.Objective of this work was to test the hypothesis that caries affected children are characterised by different level of lactoperoxidase compared to control group. Moreover lactoperoxidase secretion dependence of circadian rhytm and different methods of collecting a sample (stimulated and unstimulated saliva) were tested.Fluorimetric method with 2’,7’-dichlorofluorescin was used to determine lactoperoxidase activity. Strong correlation (r=0,839) between stimulated and unstimulated salivary LPO activity was proven. In study of circadian rhytms it was shown that the highest activity of salivary LPO is present during morning hours and at night. There were no statistically significant differences (p=0.9619, t-student test) in lactoperoxidase activity between group of caries affected children and control grup. Obtained results with low number of participants in this research does not provide a definitive answer to the hypothesis howerer it indicates that lactoperoxidase activity does not change

The Significance of Lactoperoxidase System in Oral Health: Application and Efficacy in Oral Hygiene Products

Lactoperoxidase (LPO) present in saliva are an important element of the nonspecific immune response involved in maintaining oral health. The main role of this enzyme is to oxidize salivary thiocyanate ions (SCN&#8722;) in the presence of hydrogen peroxide (H2O2) to products that exhibit antimicrobial activity. LPO derived from bovine milk has found an application in food, cosmetics, and medical industries due to its structural and functional similarity to the human enzyme. Oral hygiene products enriched with the LPO system constitute an alternative to the classic fluoride caries prophylaxis. This review describes the physiological role of human salivary lactoperoxidase and compares the results of clinical trials and in vitro studies of LPO alone and complex dentifrices enriched with bovine LPO. The role of reactivators and inhibitors of LPO is discussed together with the possibility of using nanoparticles to increase the stabilization and activity of this enzyme

Safety assessment of the modified lactoperoxidase system - In vitro studies on human gingival fibroblasts

One strategy in caries prevention is to inhibit the formation of cariogenic biofilms. Attempts are being made to develop oral hygiene products enriched with various antimicrobial agents. One of them is lactoperoxidase—an enzyme that can oxidise (pseudo)halide ions to reactive products with antimicrobial activity. Currently, commercially available products utilise thiocyanate as a substrate; however, several alternatives that are oxidised to products with greater antimicrobial potential have been found. In this study, toxicity against human gingival fibroblasts of the lactoperoxidase system was evaluated using four different (pseudo)halide substrate systems—thiocyanate, iodide, selenocyanate, and a mixture of thiocyanate and iodide. For this purpose, cells were treated with the systems and then apoptosis, cell cycle, intracellular glutathione concentration, and mitochondrial superoxide production were assessed. The results showed that each system, after generating 250 µM of the product, inhibited cell divisions, increased apoptosis, and increased the percentage of dead cells. It was concluded that the mechanism of the observed phenomena was not related to increased superoxide production or the depletion of glutathione concentration. These findings emphasised the need for the further in vitro and in vivo toxicity investigation of the modified lactoperoxidase system to assess its safety and the possibility of use in oral hygiene products