Comparative evaluation of 0.2% Chlorhexidine Mouthwash, Xylitol Chewing Gum, and Combination of 0.2% Chlorhexidine Mouthwash and Xylitol Chewing Gum on Salivary Streptococcus mutans and Biofilm Levels in 8- to 12-Year-Old Children

Combined Phase 1/2a Initial Clinical Safety Trials and Proof-of-Concept Assessment of a Novel Antimicrobial Peptide KSL-W Anti-Plaque Chewing Gum

OBJECTIVES

The effective control of dental plaque is crucial for oral health, given that pathogenic bacteria in plaque are the primary cause of dental caries. Current antimicrobial agents, although effective, disrupt the oral microbiome and lead to oral dysbiosis, hindering efforts to curb dental caries. Novel antimicrobial peptides offer a promising solution due to their selective bactericidal activity against cariogenic bacteria. This study explores the initial safety and efficacy of KSL-W formulated into chewing gum through a Phase 1 and 2a clinical trial.

METHODS

The combined trial, approved by the FDA, follows a double-blind, randomized, placebo-controlled design. Phase 1 assessed safety with single doses (2-100 mg), whereas Phase 2a explored both safety and proof of concept in reducing oral bacteria with multiple doses (4-75 mg). Besides adverse events (Phase 1), outcome measures included whole-mouth plaque and gingival index scores and bleeding on probing (Phase 2a).

RESULTS

KSL-W demonstrated safety in both phases, with no severe adverse events. The proof-of-concept analysis revealed a decrease in plaque and gingival inflammation, particularly at doses ≥ 20 mg. The 30 mg dose appeared to yield optimal effects without any adverse reactions in subjects.

CONCLUSIONS

Results from this study indicate that KSL-W is safe for use in humans and provides initial evidence of its potential efficacy in reducing plaque and gingival inflammation. Further research is essential to determine optimal usage and ultimate safety, and to assess its potential in diverse populations.

TRIAL REGISTRATION

The trial is registered with the FDA (Trial Registration Number: NCT01877421). The clinical trials were registered in the clinicaltrials.gov database under the title "Safety and Tolerability of Antiplaque Chewing Gum in a Gingivitis Population" and the identifier number is NCT01877421. The URL for accessing the study in clinicaltrials.gov is https://clinicaltrials.gov/study/NCT01877421?intr=Antiplaque%20chewing&rank=1.

Traditional Chinese Medicine Compounds Containing Lonicera japonica, Chrysanthemum morifolium, and Siraitia grosvenorii Inhibits the Growth of Streptococcus mutans

Postoperative sore throat (POST) is one of the common complications after endotracheal intubation under general anesthesia. This work attempted to design and screen out the traditional Chinese medicine (TCM) compounds containing Lonicera japonica Thunb., Chrysanthemum morifolium Ramat., and Siraitia grosvenorii (Swingle) C. Jeffrey ex A. M. Lu et Z. Y. Zhang, and further explored its antibacterial effect on POST. The antibacterial activities of Lonicera japonica, Chrysanthemum morifolium, and Siraitia grosvenorii on Streptococcus mutans (S. mutans) UA159 was measured. Lonicera japonica (40 mg/mL), Chrysanthemum morifolium (10 mg/mL), and Siraitia grosvenorii (10 mg/mL) effectively inhibited the growth of S. mutans. Then, 5 different TCM compounds were designed using the U5 (5³) uniform design experimentation method. TCM compound C3 (50 mg/mL Lonicera japonica, 10 mg/mL Chrysanthemum morifolium, and 15 mg/mL Siraitia grosvenorii) significantly promoted the inhibition zone and inhibited the biofilm formation of S. mutans. In addition, TCM compound C3 exerted great antibacterial effects on S. mutans and had the least effect on cell viability of primary human pharyngeal epithelial cells. In conclusion, this work demonstrated that TCM compound containing Lonicera japonica, Chrysanthemum morifolium, and Siraitia grosvenorii inhibited the growth of S. mutans. Thus, this study provides a theoretical basis for screening out the optimal compatibility of effective components in TCM mouthwash for relieving POST.

Development and evaluation of a chewing gum containing antimicrobial peptide GH12 for caries prevention

The purpose of this study was to develop a chewing gum containing a novel antimicrobial peptide GH12 and evaluate its biocompatibility, antimicrobial activity, and caries-preventive effects in vivo and in vitro. GH12 chewing gum was developed using a conventional method and its extracts were prepared in artificial saliva. GH12 concentration in the extracts was determined by high-performance liquid chromatography; extracts were used for growth curve assay, time-kill assay, crystal violet staining assay, scanning electron microscopy, and Cell Counting Kit-8 assay. A rat caries model was established, and molars were treated topically with extracts for 5 weeks. Weight gain monitoring, hematoxylin-eosin staining, micro-computed tomography, and Keyes scoring were conducted. Significant inhibition of Streptococcus mutans growth and biofilm formation was observed. Extracts displayed low cytotoxicity against human gingival epithelial cells. No significant differences in weight gain or signs of harm to the mucosal tissues in any of the rats were observed. Keyes scores of caries lesions in the GH12 chewing gum group were lower than those of the negative control group. It was concluded that GH12 chewing gum showed good biocompatibility, antimicrobial activity, and caries-preventive effects, exhibiting great potential to prevent dental caries as an adjuvant to regular oral hygiene.

Four-day plaque regrowth evaluation of a peptide chewing gum in a double-blind randomized clinical trial

OBJECTIVE

Antimicrobial peptide, KSL-W, formulated as an antiplaque chewing gum (APCG), was tested to evaluate the dental plaque inhibition activity and safety in an IRB approved and FDA regulated 4-day plaque regrowth clinical study.

METHODS

This Phase 2 two-armed placebo-controlled, double blind, randomized (1:1), multiple dose, and single-center study was evaluated in a proof of concept for the APCG containing 30 mg antimicrobial peptide KSL-W. Twenty six generally healthy subjects were consented and randomized into the study. The subjects were administered a dose three times per day for four treatment days following a complete dental prophylaxis. Participants were prohibited from conducting oral hygiene care (teeth brushing, flossing, and/or mouth wash rinse) for the duration of the trial. Twelve to 16 hr prior to the baseline visit, the subjects were to abstain from oral hygiene care. The Quigley-Hein Turesky plaque index (QHT) score and the oral soft tissue clinical exams were obtained at both Day 0 and Day 4.

RESULTS

All randomized study subjects that received either APCG or placebo gum completed the study with no significant adverse events recorded. The APCG significantly inhibited the regrowth of dental plaque over the course of 4 days. The whole mouth data demonstrated a difference in the QHT between the APCG and the placebo gum of 1.14 (SE = 0.27) and 95% confidence bounds of 0.58, 1.70 with a two-tailed P value of .0003.

CONCLUSION

Considering the limited sample size, the proof of concept analysis in this Phase 2 study confirmed that APCG is effective against dental plaque formation and safe for human use. (ClinicalTrials.gov Study ID# NCT02864901).

Coupling xylitol with remineralizing agents improves tooth protection against demineralization but reduces antibiofilm effect

To explore the efficiency of xylitol chewing gum enriched or not with remineralizing agents to protect tooth against cariogenic biofilm formation and demineralization. Six groups of chewing gums were prepared; Group 1: isomalt (1.8%), Group 2: casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) (3%) + isomalt (1.8%), Group 3: hydroxyapatite (HAP) (2.5%) + isomalt (1.8%), Group 4: xylitol (1.8%), Group 5: CPP-ACP (3%) + xylitol (1.8%) and Group 6: HAP (2.5%) + xylitol (1.8%). The antibiofilm properties of different chewing gum extracts using seven oral bacterial species including Streptococcus mutans, Streptococcus constellatus, Streptococcus Salivarius and Streptococcus oralis were explored via the crystal violet staining assay. The remineralizing effects of those products were assessed on thirty human permanent teeth, half-protected with varnish before chemical erosion and thermocycling process with chewing gum. Remineralization was evaluated using scanning electron microscopy and microscopic measurements on polarized light microscopy. The ratio R comparing the thickness between unvarnished and varnished sides was evaluated. While the minimum biofilm inhibitory concentration (MBIC₅₀) was low for xylitol alone compared to isomalt, it was inconsistent when enriched with remineralizing agents. The minimum biofilm eradication concentration (MBEC₅₀) was low for xylitol groups compared to isomalt, for all the studied strains. R was significantly lower in Group 1 and Group 2, while Group 6 showed the highest ratio. Xylitol chewing gums confirmed good antibiofilm properties and showed remineralized potential on eroded teeth. When xylitol is associated to CPP-ACP or HAP, antibiofilm activity decreased while remineralization of eroded teeth increased.