Streptococcus mutans attachment on a cast titanium surface

This study examined by means of scanning electron microscopy (SEM), the attachment of Streptococcus mutans and the corrosion of cast commercially pure titanium, used in dental dentures. The sample discs were cast in commercially pure titanium using the vacuum-pressure machine (Rematitan System). The surfaces of each metal were ground and polished with sandpaper (#300-4000) and alumina paste (0.3 μm). The roughness of the surface (Ra) was measured using the Surfcorder rugosimeter SE 1700. Four coupons were inserted separately into Falcon tubes contained Mueller Hinton broth inoculated with S. mutans ATCC 25175 (109 cuf) and incubated at 37 °C. The culture medium was changed every three days during a 365-day period, after which the falcons were prepared for observations by SEM. The mean Ra value of CP Ti was 0.1527 μm. After S. mutans biofilm removal, pits of corrosion were observed. Despite the low roughness, S. mutans attachment and biofilm formation was observed, which induced a surface corrosion of the cast pure titanium.

Genetic polymorphism of Streptococcus mutans strains associated with incomplete caries removal

Aim: Despite the antibacterial properties of dental materials, the survival of residual bacteria under restorations has been demonstrated after incomplete caries removal. The aim of this study was to evaluate the genetic polymorphism of Streptococcus mutans strains isolated from deep dentinal lesions before and three months after incomplete caries removal. Methods: Samples of carious dentin were collected from 33 primary and/or permanent molars before and after indirect pulp treatment and processed for microbiological isolation of mutans streptococci (MS). After three months of the dental treatment, positive cultures for MS were detected in only ten of these teeth. DNA of MS isolates were obtained and subjected to polymerase chain reaction (PCR) for identification of S mutans. The arbitrary primed-PCR method (primer OPA-13) was used to detect the genetic polymorphism of S. mutans strains. Results: Identical or highly related S. mutans genotypes were observed in each tooth, regardless of the collect. Considering each tooth separately, a maximum of nine genotypic patterns were found in each tooth from all the collects. In addition, at least one genotypic pattern was repeated in the three collects. Genetic diversity was observed among the S. mutans isolates, obtained from different teeth after three months of the dental treatment. Conclusions: The persistence of identical genotypic patterns and the genetic similarity among the isolates, from the same tooth in distinct collects, showed the resistance of some S. mutans strains after incomplete caries removal treatment.

DMFT index assessment and microbiological analysis of Streptococcus mutans in institutionalized patients with special needs

Aim: To assess the DMFT (D = decayed; M = missing; F = filled) index of institutionalized patients with mild and moderate physical and mental disabilities and to correlate it with the Streptococcus mutans (S. mutans) counts in the supragingival bacterial biofilm. Methods: Dental examination of 28 patients aged 15 to 25 years was conducted to determine the DMFT index (number of decayed, missing and filled teeth). Supragingival plaque samples were collected from the buccal surfaces of all teeth. The samples were inoculated in SB20 medium and incubated at 37 °C for 48 hours. Spearman's correlation test was applied (p = 0.05) to evaluate the correlation between the DMFT index and the amount of S. mutans. Results: The mean DMFT recorded was 7.68 and a large mean number of S. mutans colony-forming units (cfu > 10 6) was found. No statistically significant correlation was found between the DMFT index and the number of S. mutans. Conclusions: Under the conditions of this study, no correlation was found between the DMFT index and the number of S. mutans cfu in institutionalized patients with mental retardation and physical disabilities.

Susceptibility of planktonic cultures of Streptococcus mutans to photodynamic therapy with a light-emitting diode

The objective of this study was to evaluate the effect of photodynamic therapy with erythrosine and rose bengal using a light-emitting diode (LED) on planktonic cultures of S. mutans. Ten S. mutans strains, including nine clinical strains and one reference strain (ATCC 35688), were used. Suspensions containing 10 6 cells/mL were prepared for each strain and were tested under different experimental conditions: a) LED irradiation in the presence of rose bengal as a photosensitizer (RB+L+); b) LED irradiation in the presence of erythrosine as a photosensitizer (E+L+); c) LED irradiation only (P-L+); d) treatment with rose bengal only (RB+L-); e) treatment with erythrosine only (E+L-); and f) no LED irradiation or photosensitizer treatment, which served as a control group (P-L-). After treatment, the strains were seeded onto BHI agar for determination of the number of colony-forming units (CFU/mL). The results were submitted to analysis of variance and the Tukey test (p ≤ 0.05). The number of CFU/mL was significantly lower in the groups submitted to photodynamic therapy (RB+L+ and E+L+) compared to control (P-L-), with a reduction of 6.86 log 10 in the RB+L+ group and of 5.16 log 10 in the E+L+ group. Photodynamic therapy with rose bengal and erythrosine exerted an antimicrobial effect on all S. mutans strains studied.

Photodynamic inactivation of Streptococcus mutans and Streptococcus sanguinis biofilms in vitro

The purpose of this study was to evaluate specific effects of photodynamic inactivation (PDI) using erythrosine (ER) and Rose Bengal (RB) photosensitizers and a blue light-emitting diode (LED) on the viability of Streptococcus mutans and Streptococcus sanguinis biofilms. Biofilms were grown in acrylic disks immersed in broth to production of biofilms, inoculated with microbial suspension (106 cells/mL) and incubated for 48 h. After the formation of biofilms, the effects of the photosensitizers ER and RB at a concentration of 5 μM for 5 min and blue LED (455 ± 20 nm) for 180 s, photosensitizers alone and conjugated were evaluated. Next, the disks were placed in tubes with sterile physiological solution (0.9 % sodium chloride) and sonicated for to disperse the biofilms. Tenfold serial dilutions were carried and aliquots seeded in brain heart infusion agar which were then incubated for 48 h. Then the numbers colony-forming units per milliliter (CFU/mL; log 10) were counted and analyzed statistically (ANOVA, Tukey test, P ≤ 0.05). Significant decreases in the viability of all microorganisms were observed for biofilms exposed to PDI mediated by both photosensitizers. The reductions with RB and ER were, 0.62 and 0.52 log10 CFU mL -1 for S. mutans biofilms (p = 0.001), and 0.95 and 0.88 log 10 CFU mL-1 for S. sanguinis biofilms (p = 0.001), respectively. The results showed that biofilms formed in vitro by S. mutans and S. sanguinis, were sensitive to PDI using a blue LED associated with photosensitizers ER or RB, indicating its use in the control of caries and periodontal diseases. © 2012 Springer-Verlag London Ltd.

Photodynamic potential of curcumin and blue LED against streptococcus mutans in a planktonic culture

Background: The photodynamic therapy (PDT) involves the use of light of specific wavelength to activate a nontoxic photosensitizing agent or dye in the presence of oxygen for eradication of target cells. In dentistry, this therapy is used to suppress the growth of microorganisms involved directly with dental decay and periodontitis process. There are evidences that curcumin dye is able to control microbial activity when illuminated with specific wavelength. The purpose of this study was to evaluate the in vitro efficacy of PDT using curcumin dye (Cur-C) in combination with a blue LED (L) device on a planktonic model of Streptococcus mutans ( S. mutans). Methods: Suspensions (0.5mL) containing S. mutans at 1×107CFUmL-1 were prepared and divided into 4 groups: Group C-L- (control: no treatment and 1 experimental condition), Group C+L- (curcumin at 3 different concentrations: 2000; 4000 and 8000μM and 3 experimental conditions), Group C-L+ (LED at 3 different dosages: 24, 48 and 72Jcm-2 and 3 experimental conditions), and Group C+L+ (PDT group: curcumin at respective concentrations combined to LED dosages and 9 experimental conditions). Samples of each experimental condition were cultured in Petri dishes of BHI agar. Incubation in micro-aerophilia at 37°C for 48h was performed for subsequent visual counting of CFU/mL. Data were transformed into log10 and analyzed by two-way ANOVA and Tukey's test at p<0.05. Results: Group C. +. L+, in specific experimental conditions, demonstrated a log bacterial reduction 70% higher than Group C. -. L-. Both groups C. -. L+ and C. +. L- presented a slight decrease in log bacterial counting. Conclusion: This in vitro method was able to reduce the number of S. mutans in a planktonic suspension. © 2013 Elsevier B.V.

Efeitos da terapia fotodinâmica in vitro em biofilmes formados por Candida albicans, Staphylococcus aureus e Streptococcus mutans

Pós-graduação em Biopatologia Bucal - ICT

Ensaio de citotoxicidade de extratos naturais após determinação da concentração microbicida mínima para Staphylococcus spp., Streptococcus mutans e Candida spp

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da atividade antimicrobiana de extratos vegetais da savana brasileira sobre Streptococcus mutans e a sua capacidade de desmineralização e a adesão à superfície de vidro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Contaminação cruzada em escovas dentais por Streptococcus mutans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento e caracterização de sistemas nanoestruturados bioadesivos contendo peptídeo análogo à adesina do streptococcus mutans

Pós-graduação em Ciências Farmacêuticas - FCFAR

Avaliação da atividade dos óleos essenciais de cymbopogon citratus (D.C.) Stapf, Tagetes minuta L. e Curcuma zedoaria roscoe frente aos microrganismos Candida spp., Staphylococcus spp. e Streptococcus mutans

Pós-graduação em Biopatologia Bucal - ICT

Aderência de Streptococcus mutans em materiais restauradores e seus efeitos em cárie secundária in vitro E in situ avaliados por microscopia de luz polarizada e espectroscopia por dispersão de raios-X (EDS)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito do extrato da folha de Psidium cattleianum na expressão protéica de Streptococcus mutans, no biofilme bacteriano e na desmineralização do esmalte

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Topografia superficial e aderência de Streptococcus mutans no titânio após imersão e escovação com dentifrícios fluoretado e não-fluoretado simulando 10 anos de uso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)