Antibacterial Activity of a Bioactive Tooth-Coating Material Containing Surface Pre-Reacted Glass in a Complex Multispecies Subgingival Biofilm.

Bioactive materials were developed with the ability to release fluoride and provide some antimicrobial potential, to be widely used in dentistry today. However, few scientific studies have evaluated the antimicrobial activity of bioactive surface pre-reacted glass (S-PRG) coatings (PRG Barrier Coat, Shofu, Kyoto, Japan) on periodontopathogenic biofilms. This study evaluated the antibacterial activity of S-PRG fillers on the microbial profile of multispecies subgingival biofilms. A Calgary Biofilm Device (CBD) was used to grow a 33-species biofilm related to periodontitis for 7 days. The S-PRG coating was applied on CBD pins from the test group and photo-activated (PRG Barrier Coat, Shofu), while the control group received no coating. Seven days after treatment, the total bacterial counts, metabolic activity, and microbial profile of the biofilms were observed using a colorimetric assay and DNA-DNA hybridization. Statistical analyses were applied; namely, the Mann-Whitney, Kruskal-Wallis, and Dunn's post hoc tests. The bacterial activity of the test group was reduced by 25.7% compared with that of the control group. A statistically significant reduction was observed for the counts of 15 species: A. naeslundii, A. odontolyticus, V. parvula, C. ochracea, C. sputigena, E. corrodens, C. gracilis, F. nucleatum polymorphum, F. nucleatum vincentii, F. periodonticum, P. intermedia, P. gingivalis, G. morbillorum, S. anginosus, and S. noxia (p ≤ 0.05). The bioactive coating containing S-PRG modified the composition of the subgingival biofilm in vitro, thereby decreasing colonization by pathogens.

Incorporation of zinc into cetylpyridinium chloride mouthwash affects the composition of multispecies biofilms.

This study evaluated the effect of a mouthwash containing 0.075% cetylpyridinium chloride and 0.28% zinc lactate (CPC + Zn) in a multispecies biofilm model. A 7-days 33-species biofilm, formed on Calgary device, was 1-min treated with: 0.12% chlorhexidine (CHX), culture medium (negative control), 0.075% cetylpyridinium chloride (CPC) or CPC + Zn, 2x/day, from day 3 until day 6. The metabolic activity and the microbial composition were evaluated by colorimetric method and checkerboard DNA-DNA hybridization, respectively. The three antimicrobials (CPC, CPC + Zn and CHX) reduced metabolic activity, total biofilm count and several species counts, including Porphyromonas gingivalis, Fusobacterium nucleatum, Parvimonas micra, Campylobacter gracilis and Streptococcus mutans. However, only CPC + Zn reduced counts of the pathogen Prevotella intermedia and did not interfere with the levels of some beneficial species in relation to the negative control. The treatment of multispecies subgingival biofilm with CPC + Zn was effective in controlling periodontal pathogens and favored the colonization of health-associated bacterial species.

Anti-Inflammatory Effects of (3S)-Vestitol on Peritoneal Macrophages.

The isoflavone (3S)-vestitol, obtained from red propolis, has exhibited anti-inflammatory, antimicrobial, and anti-caries activity; however, few manuscripts deal with its anti-inflammatory mechanisms in macrophages. The objective is to elucidate the anti-inflammatory mechanisms of (3S)-vestitol on those cells. Peritoneal macrophages of C57BL6 mice, stimulated with lipopolysaccharide, were treated with 0.37 to 0.59 µM of (3S)-vestitol for 48 h. Then, nitric oxide (NO) quantities, macrophages viability, the release of 20 cytokines and the transcription of several genes related to cytokine production and inflammatory response were evaluated. The Tukey-Kramer variance analysis test statistically analyzed the data. (3S)-vestitol 0.55 µM (V55) lowered NO release by 60% without altering cell viability and diminished IL-1ß, IL-1α, G-CSF, IL-10 and GM-CSF levels. V55 reduced expression of Icam-1, Wnt5a and Mmp7 (associated to inflammation and tissue destruction in periodontitis) and Scd1, Scd2, Egf1 (correlated to atherosclerosis). V55 increased expression of Socs3 and Dab2 genes (inhibitors of cytokine signaling and NF-κB pathway), Apoe (associated to atherosclerosis control), Igf1 (encoder a protein with analogous effects to insulin) and Fgf10 (fibroblasts growth factor). (3S)-vestitol anti-inflammatory mechanisms involve cytokines and NF-κB pathway inhibition. Moreover, (3S)-vestitol may be a candidate for future in vivo investigations about the treatment/prevention of persistent inflammatory diseases such as atherosclerosis and periodontitis.

Metabolic activity of hydro-carbon-oxo-borate on a multispecies subgingival periodontal biofilm: a short communication.

OBJECTIVE: This study evaluated the metabolic activity of hydro-carbon-oxo-borate complex (HCOBc) on a multispecies subgingival biofilm as well as its effects on cytotoxicity. MATERIALS AND METHODS: The subgingival biofilm with 32 species related to periodontitis was formed in the Calgary Biofilm Device (CBD) for 7 days. Two different therapeutic schemes were adopted: (1) treatment with HCOBc, 0.12% chlorhexidine (CHX), and negative control group (without treatment) from day 3 until day 6, two times a day for 1 min each time, totaling 8 treatments and (2) a 24-h treatment on a biofilm grown for 6 days. After 7 days of formation, biofilm metabolic activity was determined by colorimetry assay, and bacterial counts and proportions of complexes were determined by DNA-DNA hybridization. Both substances' cytotoxicity was evaluated by cell viability (XTT assay) and clonogenic survival assay on ovary epithelial CHO-K1 cells and an osteoblast precursor from calvaria MC3T3-E1 cells. RESULTS: The first treatment scheme resulted in a significant reduction in biofilm's metabolic activity by means of 77% by HCOBc and CHX treatments versus negative control. The total count of 11 and 25 species were decreased by treatment with hydro-carbon-oxo-borate complex and CHX, respectively, compared with the group without treatment (p < 0.05), highlighting a reduction in the levels of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Fusobacterium periodontium. CHX significantly reduced the count of 10 microorganisms compared to the group treated with HCOBc (p < 0.05). HCOBc and CHX significantly decreased the pathogenic red-complex proportion compared with control-treated biofilm, and HCOBc had even a more significant effect on the red complex than CHX had (p ≤ 0.05). For the second treatment scheme, HCOBc complex and CHX significantly decreased 61 and 72% of control biofilms' metabolic activity and the counts of 27 and 26 species, respectively. HCOBc complex did not significantly affect the proportions of formed biofilms, while CHX significantly reduced red, orange, and yellow complexes. Both substances exhibited similar cytotoxicity results. CONCLUSIONS: This short communication suggested that the HCOBc complex reduced a smaller number of bacterial species when compared to chlorhexidine during subgingival biofilm formation, but it was better than chlorhexidine in reducing red-complex bacterial proportions. Although HCOBc reduced the mature 6-day-old subgingival multispecies biofilms, it did not modify bacterial complexes' ratios as chlorhexidine did on the biofilms mentioned above. Future in vivo studies are needed to validate these results. CLINICAL RELEVANCE: HCOBc complex could be used to reduce red-complex periodontal bacterial proportions.

Antimicrobial effects of a pulsed electromagnetic field: an in vitro polymicrobial periodontal subgingival biofilm model.

The objective was to test the influence of a pulsed electromagnetic field (PEMF) on bacterial biofilm colonization around implants incorporated with healing abutments. Healing abutments with (test group) and without (control group) active PEMF devices were placed in a multispecies biofilm consisting of 31 different bacterial species. The biofilm composition and total bacterial counts (x105) were analyzed by checkerboard DNA-DNA hybridization. After 96 h, the mean level of 7 out of the 31 bacterial species differed significantly between groups, namely Eubacterium nodatum, Fusobacterium nucleatum ssp. nucleatum, Streptococcus intermedius, Streptococcus anginosus, Streptococcus mutans, Fusobacterium nucleatum ssp. Vicentii and Capnocytophaga ochracea were elevated in the control group (p < 0.05). The mean total bacterial counts were lower in the Test group vs the control group (p < 0.05). An electromagnetic healing cap had antimicrobial effects on the bacterial species and can be used to control bacterial colonization around dental implants. Further clinical studies should be conducted to confirm these findings.