Chitosan gel prevents the growth of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in mini-implant during orthodontic treatment

Comparative evaluation of orthodontic mini-implants hygiene protocols on subgingival bacterial load

OBJECTIVE

The aim of this study was to evaluate the effectiveness of four hygiene protocols for orthodontic mini-implants in reducing the subgingival bacterial load in the peri-implant sulcus.

METHODS

Thirty-nine healthy individuals who had fifty-nine as-received mini-implants (20 men, 19 women, 20 to 42 years old) were randomly distributed into four groups of hygiene protocols: mechanical hygiene (M); mechanical hygiene associated with 0.12% digluconate chlorhexidine (CHX), 0.03% triclosan (T), or 0.05% cetylpyridinium chloride (CP). All individuals were instructed regarding the hygiene procedures (T0). For bacterial load analysis, the gingival crevicular fluid from peri-implant sulcus was collected and submitted to quantitative real-time PCR at baseline (T1) and after 21 days following the hygiene protocols (T2). Wilcoxon test was applied for intergroup comparisons, whereas differences among groups at each time point were examined by Kruskal-Wallis test. The significance level was 5%.

RESULTS

Significant difference was detected between baseline and post-protocol times for bacterial total counts, comparing intergroup results, except for mechanical hygiene associated with cetylpyridinium chloride (M p=0.018, CHX p=0.028, T p=0.012, CP p=0.065). No significant difference was detected among the evaluated methods (p=0.181).

CONCLUSIONS

The mechanical hygiene of orthodontic mini-implants itself was capable to reduce total bacteria load and keep devices clean. Commonly, orthodontists prescribe, in addition to mechanical biofilm removal, some protocols combining adjunctive chemical agents as chlorhexidine. The authors believe that results have large importance for dental community, as they can protect patients from overtreatment.

Exploring the antimicrobial efficacy of tea tree essential oil and chitosan against oral pathogens to overcome antimicrobial resistance

BACKGROUND

Considering that antimicrobial resistance among oral pathogens is a significant concern in dental practice, with broader implications for overall health due to the oral microbiota serving as a reservoir for antibiotic resistance genes (ARGs), research into natural products is crucial for addressing this issue.

OBJECTIVE

This study aimed to evaluate tea tree oil (TTO) and chitosan (CH) performance against oral pathogens, including mixed-species biofilm, and its effects on bacteria growth, in addition to chemical characterization and cytotoxicity of TTO.

METHODS

Tea Tree Oil and low molecular weight chitosan were used in this study. The chemical composition of TTO was analyzed using gas chromatography coupled with mass spectrometry (GC-MS). To evaluate TTO's antimicrobial properties, time-kill and cell viability assays were conducted. Additionally, minimum inhibitory concentration (MIC), minimum microbiocidal concentration (MMC), checkerboard, and biofilm assays were performed using TTO and CH alone and in combination.

RESULTS

TTO chromatography peaks found consistent with the standard ISO4730:2017 and literature. TTO and CH exhibited inhibitory activity against all tested microorganisms. The predominantly microbiostatic activity of TTO is probably related to terpinen-4-ol associated with terpinene. The oil at MIC value was able to delay the log phase of Aggregatibacter actinomycetemcomitans growth. Fibroblasts (L929) viability remained above 70 % during 24 h for TTO concentrations ranging from 0.5 to 0.0625 mg/ml. TTO-CH combination showed a synergistic activity (FIC = 0.5) against A. actinomycetemcomitans and Streptococcus sanguinis, at a concentration of 0,25MIC for both species. The compounds at MIC concentration inhibited both monospecies and mixed-species biofilms studied bacteria to the same extent as the azithromycin control.

CONCLUSION

TTO and CH demonstrated efficacy in combating oral pathogens and TTO-CH combination offers a promising approach to confront microbial resistance in the oral environment.

Antibacterial efficacy, calcium ion release, and pH using calcium hydroxide with three vehicles

Context

Vehicles combined with calcium hydroxide, as an intracanal medicament, play a key factor in affecting antibacterial, calcium release, and pH.

Aims

The aim of this study is to investigate the effect of three vehicles (glycerin, chlorhexidine gluconate/CHX, and chitosan nanoparticle) combined with calcium hydroxide as an intracanal medicament on antibacterial efficacy against Enterococcus faecalis, calcium ion release, and pH of at different interval times of 7 and 14 days.

Settings and Design

The research was experimental laboratory.

Materials and Methods

Each study used 24 samples of eight teeth each and was randomly divided into three groups based on the vehicle of calcium hydroxide: group 1: glycerin, group 2: CHX, and group 3: chitosan nanoparticles. Each vehicle group was then further divided into two subgroups of four teeth based on the interval times (group A: 7 days and group B: 14 days). The antibacterial efficacy was determined using an agar diffusion method. Calcium ion release was analyzed with atomic absorption spectrometry, and pH was measured using a pH meter.

Statistical Analysis Used

Data from each study were analyzed by two-way ANOVA, followed by Tukey's test with a significance level of 95%.

Results

The results exhibited that chitosan nanoparticles had the highest antibacterial efficacy against E. faecalis, calcium ion release, and pH, while the lowest was glycerin at 7 and 14 days (P < 0.05).

Conclusion

Calcium hydroxide combined with chitosan nanoparticle as an intracanal medicament produced the highest antibacterial efficacy against E. faecalis, calcium ion release, and pH than glycerin and CHX at intervals of 7 and 14 days.