Antibacterial effectiveness of probiotic-based experimental mouthwash against cariogenic pathogen: An in vitro study

Effect of Chitosan and Acrylic Acid Addition to Acrylic Resin on Porosity and Streptococcus mutans Growth in Denture Base

OBJECTIVE

 This work aimed to determine the effect of adding chitosan and acrylic acid to acrylic resin denture base on the porosity of the material and the growth of Streptococcus mutans.

MATERIALS AND METHODS

 This study is an experimental laboratory research. Samples were divided into the following three groups (n = 10): group 1 was the control group, group 2 was the acrylic resin mixture with 1% chitosan and acrylate acid, and group 3 was the acrylic resin mixture with 2% chitosan and acrylate acid. S. mutans growth was tested using the dilution method, and porosity was examined using an optical microscope. Data were calculated by one-way analysis of variance (p < 0.05) and correlation analysis.

RESULTS

 The acrylic resin added with 2% chitosan and acrylic acid showed pores with an almost spherical shape and the smallest size. Significant difference (p < 0.05) was observed among all the groups. A positive and extremely strong correlation was found between porosity and S. mutans growth.

CONCLUSION

 Chitosan and acrylic acid at 1 and 2% concentrations can be added to acrylic resin to minimize the porosity of the denture base and reduce the growth of S. mutans. A less porous denture is associated with a low S. mutans growth rate.

Comparative Evaluation of 3 Commercial Mouthwash Formulations on Clinical Parameters of Chronic Gingivitis

BACKGROUND Chlorhexidine (CHX) is not prescribed as a mouthwash for long-term use; therefore, probiotic/herbal mouthwashes are being investigated. This study compared the effect of 3 commercial mouthwashes on plaque index (PI), gingival index (GI), and bleeding index (BI) in patients with chronic gingivitis. MATERIAL AND METHODS Forty-five patients (all with moderate plaque) were randomly allocated into 3 groups (Gp): Gp 1 (CHX), Gp 2 (Manuka), and Gp 3 (Pro-Dental). Three periodontal clinical parameters - PI, GI, and BI - were recorded at baseline and on days 7, 14, and 28. An oral hygiene maintenance program was followed by a double-blinded intervention (coded bottle containing mouthwash). Both inter-group and intra-group comparisons were made using analysis of variance (ANOVA) with multiple t tests. All probable values were considered to have various levels of significance at P<0.05 or below. RESULTS All indices for all groups showed higher values (mean) at baseline, which were lower on days 7, 14, and 28. No differences in any clinical parameter at any point of time existed between Gp 1 and Gp 2. There were, however, significant differences (P<0.05) between Gp 1/Gp 3 and Gp 2/Gp 3 for all clinical parameters at all observed time periods (days 7, 14, 28). Intra-group comparison for all groups demonstrated highly significant differences between baseline values and other time points. CONCLUSIONS For managing chronic gingivitis, Manuka mouthwash is as effective as a CHX mouthwash, as there were no differences observed in any clinical parameters at any point points.

Characterization and potential oral probiotic properties of Lactobacillus plantarum FT 12 and Lactobacillus brevis FT 6 isolated from Malaysian fermented food

OBJECTIVE

This study aims to characterise the lactic acid bacteria (LAB) isolated from local Malaysian fermented foods with oral probiotics properties.

DESIGN

The LAB strains isolated from Malaysian fermented foods, Lactobacillus brevis FT 6 and Lactobacillus plantarum FT 12, were assessed for their antimicrobial properties against Porphyromonas gingivalis ATCC 33277 via disc diffusion assay. Anti-biofilm properties were determined by treating the overnight P. gingivalis ATCC 33277 biofilm with different concentrations of LAB cell-free supernatant (LAB CFS). Quantification of biofilm was carried out by measuring the optical density of stained biofilm. The ability of L. brevis FT 6 and L. plantarum FT 12 to tolerate salivary amylase was also investigated. Acid production with different sugars was carried out by pH measurement and screening for potential antimicrobial organic acid by disc diffusion assay of neutralised probiotics CFS samples. In this study, L. rhamnosus ATCC 7469, a commercial strain was used to compare the efficacy of the isolated strain with the commercial strain.

RESULTS

Lactobacillus brevis FT 6 and L. plantarum FT 12 possess antimicrobial activity against P. gingivalis with inhibition diameters of more than 10 mm, and the results were comparable with L. rhamnosus ATCC 7469. The MIC and MBC assay results for all tested strains were recorded to be 25 µl/µl concentration. All LAB CFS reduced biofilm formation proportionally to the CFS concentration and tolerated salivary amylase with more than 50% viability. Overnight cultures of all lactic acid bacteria strains showed a pH reduction and neutralised CFS of all lactic acid bacteria strains did not show any inhibition towards P. gingivalis.

CONCLUSIONS

These results indicate that the isolated probiotics have the potential as probiotics to be used as a supportive oral health treatment, especially against a periodontal pathogen, P. gingivalis.

Effect of Zamzam Water on Microhardness of Primary Tooth Enamel After Erosion Induced by Claritin Syrup: An In-vitro Study

Background:

Dental erosion is an irreversible damage to hard tissues in the mouth due to acid dissolution not induced by microorganisms. Oral medications contributed to the etiology of dental erosion. Among these medications, antihistamine-containing syrups were reported to have a considerable erosive effect on hard dental tissues.

Objective:

The objective was to evaluate the effect of Zamzam water on the microhardness of primary tooth enamel after erosion induced by Claritin™ syrup.

Materials and Methods:

The present in-vitro study was conducted on 25 primary central incisor teeth. The labial surfaces of the specimens were prepared for microhardness testing. Baseline microhardness was measured first, then the samples were submerged in the erosive agent Claritin™ syrup, for 30 min every 12 h for 12 days. Thereafter, all the teeth were placed in Zamzam water for 30 min every 12 h for 12 days. The microhardness was measured by the Vickers hardness tester and expressed as Vickers microhardness value (VH). The measurements were completed three times for the same sample: baseline, after erosion, and after Zamzam treatment. Data were analyzed statistically using one-way repeated analysis of variance (ANOVA) followed by Tukey’s post hoc test.

Results:

The primary teeth included in this study showed a significant increase in their surface microhardness after Zamzam water treatment; the mean value of VH was increased from 33.12 ± 1.62 to 89.32 ± 8.52 (P-value <0.0001).

Conclusion:

Zamzam water could be introduced as a part of the management of dental erosion in the primary dentition.

Probiotic Effects of Lactobacillus paracasei 28.4 to Inhibit Streptococcus mutans in a Gellan-Based Formulation

Streptococcus mutans is considered to be a major bacterium involved in dental caries, and the control of virulence mechanisms is fundamental to prevent disease. Probiotics present a promising preventive method; however, the use of probiotics requires its incorporation into delivery materials to facilitate oral colonization. Thus, we performed a comprehensive study examining preventive effects of Lactobacillus paracasei 28.4-enriched gellan hydrogel materials to inhibit S. mutans in planktonic and biofilm states, addressing its influence in the production of extracellular polysaccharides (EPS) and altered gene expression of several cariogenic virulence factors. L. paracasei 28.4, a strain isolated from the oral cavity of a caries-free individual, was incorporated in three gellan hydrogels (0.5%, 0.75%, and 1% w/v). The pretreatment with probiotic-gellan formulations provided a release of L. paracasei cells over 24 h that was sufficient to inhibit the planktonic growth of S. mutans, independent of the gellan concentrations and pH variations. This pretreatment also had inhibitory activity against S. mutans biofilms, exhibiting a reduction of 0.57 to 1.54 log₁₀ in CFU/mL (p < 0.0001) and a decrease of 68.8 to 71.3% in total biomass (p < 0.0001) compared with the control group. These inhibitory effects were associated with the decreased production of EPS by 80% (p < 0.0001) and the downregulation of luxS, brpA, gbpB, and gtfB genes. The gellan formulation containing L. paracasei 28.4 exhibited probiotic effects for preventing S. mutans growth, biofilm formation, and production of cariogenic factors to suggest possible use in tooth decay prevention.

Antibacterial and Remineralization Efficacy of Casein Phosphopeptide, Glycomacropeptide Nanocomplex, and Probiotics in Experimental Toothpastes: An In Vitro Comparative Study

Objective  This article evaluates the antibacterial and remineralization potential of experimentally prepared toothpastes containing different mixtures of nano casein phosphopeptides (nCPP), nano amorphous calcium phosphate (nACP), probiotic ­ Lactobacillus rhamnosus B-445 ( L. rhamnosus ), and nano glycomacropeptide (nGMP).

Materials and Methods  Five experimental toothpaste samples were prepared and grouped, such that group (A0) was the experimental toothpaste base formula. Groups (A1), (A2), (A3), and (A4) were the experimental toothpastes containing: nCPP; nCPP and nACP; nCPP, nACP, and L. rhamnosus , and nCPP, nACP, and nGMP, ­respectively. Group (A5) was the commercial group (GC MI Paste Plus). The five groups were screened against Streptococcus mutans (ATCC 25175) growth, and investigated for their remineralizing potentials on demineralized bovine enamel using Vickers ­microhardness test (Vickers hardness number [VHN]). Scanning electron microscope (SEM) images were obtained for the demineralized and remineralized enamel of the two most effective toothpastes against in vitro bacterial induced enamel demineralization. Statistical analysis was performed using one-way analysis of variance (ANOVA) as well as repeated measures ANOVA followed by Tukey’s post hoc test.

Results  Both (A3) and (A4) were significantly higher in mean inhibition zone ­diameters than group (A1) and (A2). Group (A4) showed the highest statistical ­significance in the mean difference between VHN values of demineralization and 15 days remineralization period. SEM images showed the deposition of nano-sized particles fill the ­microrough surface pattern of the etched enamel.

Conclusion  All these findings suggest the use of probiotic, nCPP–nACP, and nGMP as a dental anticariogenic and remineralizing active agents.