Short-term relative antibacterial effect of octenidine dihydrochloride on the oral microflora in orthodontically treated patients

Efficacy of adjunctive octenidine hydrochloride as compared to chlorhexidine and placebo as adjuncts to instrumentation in stage I-II periodontitis: A double-blinded randomized controlled trial

OBJECTIVES

This randomized, controlled, double-blinded clinical trial aimed to evaluate the efficacy of octenidine hydrochloride and chlorhexidine mouthwashes as adjuncts to instrumentation in stage I-II periodontitis patients.

METHODS

Forty-five patients with mild-to-moderate periodontitis were randomly allocated to three groups: 0.1% octenidine dihydrochloride (OCT), placebo, and 0.12% chlorhexidine (CHX) mouthwashes. Patients were instructed to use the mouthwash after instrumentation for twice a day up to 3 weeks. Periodontal parameters such as probing pocket depth (PPD), clinical attachment loss (CAL), O'Leary plaque index (PI), Loe and Silness gingival index (GI), Lobene stain index (SI), and oral soft tissue changes were recorded at baseline and once every week for 3 weeks. The visual analogue scale (VAS) was also recorded as a self-administered questionnaire at the end of the study. The one-way ANOVA was used to compare VAS scores between the groups. The repeated measures ANOVA and post hoc Newman-Keuls tests were used to assess the differences in the periodontal parameters between groups at different time intervals. The Kruskal-Wallis test was used to compare the mean SI.

RESULTS

There was a significant reduction in the mean GI of the OCT and CHX groups compared to placebo (p < 0.05). OCT usage resulted in significantly less staining, according to mean SI, when compared to CHX. Furthermore, VAS scores revealed that OCT was significantly the preferred mouthwash (p < 0.01).

CONCLUSION

Adjunctive octenidine hydrochloride may be an alternative to chlorhexidine in its ability to control the periodontal parameters in patients with stage I-II periodontitis. Further larger studies are necessary to confirm these findings.

Rapid synthesis of drug-encapsulated films by evaporation-induced self-assembly for highly-controlled drug release from biomaterial surfaces

Infection at the surgical site for dental implants results in failed procedures, patient pain, burdensome economic impact, and the over-prescription of prophylactic antibiotics. Mesoporous silica films as coatings for implants may provide an ideal antimicrobial drug storage and local release vector to the site of infection, however traditional drug loading techniques result in insufficient drug load and short-term release kinetics. In this work, we have applied a method to use a surfactant-antimicrobial drug octenidine dihydrochloride (OCT) as a template for mesostructured silica, to demonstrate silica-OCT composite films. The films are synthesized by evaporation induced self-assembly (EISA) and we explore the effects of synthesis parameters on porous film structure, OCT incorporation, and OCT drug release rates. Drug micelle incorporation into the silica mesostructure was highly dependent on silica precursor pre-reaction to form silica oligomers before film spin-casting. The OCT drug concentration of the synthesis solution dictated the time required for effective incorporation (without phase separation), with total loading in the film of up to 90% by mass. The OCT content in the films was found to directly determine the timescale of drug release, from 2 to 8 h for a single layer film. The total release timescale was increased by the addition of multiple layers of OCT-silica films to nearly 2 weeks. Drug release from films completely inhibited Streptococcus mutans (UA159) growth, while drug-free porous silica films showed no increase in bacterial growth over non-porous control. These OCT-silica films have a significant potential to store and release antimicrobial drugs from dental implant surfaces.

Effect of octenidine mouthwash on plaque, gingivitis, and oral microbial growth: A systematic review

OBJECTIVE

Octenidine dihydrochloride is an antimicrobial cationic surfactant compound. We conducted a systematic review to determine the efficacy of octenidine-based mouthwash on plaque formation, gingivitis, and oral microbial growth in subjects with or without periodontal disease.

MATERIALS AND METHODS

PubMed/MEDLINE, ScienceDirect, Google Scholar, and Cochrane Library were searched for relevant studies. The review was conducted per PRISMA guidelines. Only randomized controlled trials and observational studies comparing octenidine with placebo or other mouthwashes in healthy subjects with or without periodontal disease, were considered for this review. The endpoints included percentage reduction in plaque index (PI), gingival index (GI), absolute reduction in the mean number of colony-forming units (CFU/ml [log₁₀ ]) and adverse effects (AEs; tooth staining/mucosal tolerance).

RESULTS

Ten randomized controlled and six observational studies fulfilled the selection criteria. Twice or thrice daily rinsing with 0.1% octenidine for 30-60 s produced significant reduction in plaque, gingivitis and oral microbial growth. Compared to control mouthwash or baseline, 0.1% octenidine inhibited plaque formation by ~38.7%-92.9%, which was either equal or greater than that of chlorhexidine gluconate. 0.1% octenidine reduced gingivitis by ~36.4%-68.37% versus control mouthwash or baseline and microbial growth by 0.37-5.3 colony-forming units (vs. chlorhexidine: 0.4-4.23 colony-forming units). Additional benefits of 0.1% octenidine were significant reduction in the number of bleeding sites, papilla bleeding index, sulcus bleeding index, and gingival fluid flow.

CONCLUSION

Within the limitations of this study, there exists moderate evidence that 0.1% OCT was found to be an effective antiplaque agent. Octenidine inhibited plaque formation upto 93% and gingivitis upto 68% versus placebo and was either superior or comparable to chlorhexidine. Octenidine was well-tolerated and safe and can be an effective alternative to CHX and other contemporary mouthwashes.

Effects of Octenidine on the Formation and Disruption of Dental Biofilms: An Exploratory In Situ Study in Healthy Subjects

Dental biofilms are highly structured, complex multispecies communities that, if left untreated, lead to severe oral complications such as caries and periodontal diseases. Therefore, antibiofilm agents are often recommended for both preventive and therapeutic measures. However, biofilm management can be challenging due to the low sensitivity of biofilms to antimicrobial treatments. Octenidine dihydrochloride (OCT) is a highly effective antibacterial agent. Because the OCT antibiofilm efficacy has not been studied in situ, this exploratory crossover study aimed to evaluate the effects of OCT mouth rinsing on biofilm formation and on the disruption of mature biofilms. Moreover, a comparison to the gold-standard chlorhexidine (CHX) was conducted. The biofilms were formed intraorally by 5 healthy volunteers on enamel specimens fixed to acrylic splints. For biofilm formation analysis, OCT, CHX, or water rinses were applied for 30 s every 12 h. The samples evaluation took place at 24-and 48-h time points. For biofilm disruption analysis, sample assessment was performed before and directly after the first OCT or CHX rinse on 48-h mature biofilms. A second rinse was carried out 12 h later. The last assessment was applied to 72-h mature biofilms. The biofilms were analyzed by fluorescence microscopy and transmission electron microscopy. The results showed OCT significantly reducing biofilm formation and bacterial vitality in situ. Simultaneously, the biofilm thickness was strongly decreased. Moreover, a single application of OCT to a 48-h mature biofilm induced substantial biofilm disruption. In addition, the efficacy of OCT compared favorably to CHX. These findings show that OCT rinses prevent biofilm formation and disrupt preexisting mature biofilms formed by healthy subjects. This work suggests that OCT might be used for dental biofilm management as a part of the medical treatment of oral diseases. Future studies with a larger subject heterogeneity and number are needed to confirm the observed OCT effects.

Responsive antimicrobial dental adhesive based on drug-silica co-assembled particles

Most dental resin composite restorations are replacements for failing restorations. Degradation of the restoration-tooth margins by cariogenic bacteria results in recurrent caries, a leading cause for restoration failure. Incorporating antimicrobial agents in dental adhesives could reduce interfacial bacterial count and reduce recurrent caries rates, inhibit interfacial degradation, and prolong restoration service life, while minimizing systemic exposure. Direct addition of antimicrobial compounds into restorative materials have limited release periods and could affect the integrity of the material. Attempts to incorporate antimicrobial within mesoporous silica nanoparticles showed theoretical promise due to their physical robustness and large available internal volume, yet yielded short-term burst release and limited therapeutic payload. We have developed novel broad-spectrum antimicrobial drug-silica particles co-assembled for long-term release and high payload incorporated into dental adhesives. The release of the drug, octenidine dihydrochloride, is modulated by the oral degradative environment and mathematically modeled to predict effective service life. Steady-state release kills cariogenic bacteria, preventing biofilm formation over the adhesive surface, with no toxicity. This novel material could extend dental restoration service life and may be applied to other long-term medical device-tissue interfaces for responsive drug release upon bacterial infection.

STATEMENT OF SIGNIFICANCE

This study describes a novel dental adhesive that includes a broad-spectrum antimicrobial drug-silica co-assembled particles for long-term antimicrobial effect. The release of the drug, octenidine dihydrochloride, is modulated by the oral degradative environment and mathematically modeled to predict effective release throughout the service life of the restoration. Steady-state drug-release kills caries-forming bacteria, preventing biofilm formation over the adhesive surface, without toxicity. This novel material could extend dental restoration service life and may be applied to other long-term medical device-tissue interfaces for responsive drug release upon bacterial infection. Since recurrent cavities (caries) caused by bacteria are the major reason for dental filling failure, this development represents a significant contribution to the biomaterials field in methodology and material performance.

Drug self-assembly for synthesis of highly-loaded antimicrobial drug-silica particles

Antimicrobial drug release from biomaterials for orthopedic repair and dental restorations can prevent biofilm growth and caries formation. Carriers for drug incorporation would benefit from long-term drug storage, controlled release, and structural stability. Mesoporous silica, synthesized through a co-assembly of silica and surfactant template, is an ideal drug encapsulation scaffold that maintains structural integrity upon release. However, conventional loading of drug within meso-silica pores via concentration-gradient diffusion limits the overall payload, concentration uniformity, and drug release control. Herein we demonstrate the co-assembly of an antimicrobial drug (octenidine dihydrochloride, OCT), and silica, to form highly-loaded (35% wt.) OCT-silica nanocomposite spheres of 500 nm diameter. Drug release significantly outlasted conventional OCT-loaded mesoporous silica, closely fit Higuchi models of diffusive release, and was visualized via electron microscopy. Extension of this concept to the broad collection of self-assembling drugs grants biomedical community a powerful tool for synthesizing drug-loaded inorganic nanomaterials from the bottom-up.

Mouthwashes in the 21st century: a narrative review about active molecules and effectiveness on the periodontal outcomes

INTRODUCTION

Poor oral hygiene is a major risk factor for oral diseases. Regular home-based care is essential to maintain good oral hygiene. In particular, mouthrinses can support conventional tooth brushing in reducing accumulation of oral plaque. Areas covered: The most common molecules contained in mouthrinses (chlorhexidine, essential oils, cetyl pyridinium chloride, triclosan, octeneidine, delmopinol, polyvinylpyrrolidone, hyaluronic acid, natural compounds) are discussed, together with relevant clinical and in vitro studies, focusing on their effects on periodontal health. Currently, chlorhexidine is the most efficacious compound, with both antiplaque and antibacterial activities. Similar results are reported for essential oils and cetyl pyridinium chloride, although with a somewhat reduced efficacy. Considering the adverse effects of chlorhexidine and its time-related characteristics, this molecule may best be indicated for acute/short-term use, while essential oils and cetyl pyridinium chloride may be appropriate for long-term, maintenance treatment. Expert opinion: The literature has not clearly demonstrated which compound is the best for mouthrinses that combine good efficacy and acceptable side effects. Research should focus on substances with progressive antibacterial activity, prompting a gradual change in the composition of oral biofilm and mouthrinses that combine two or more molecules acting synergistically in the mouth.

Cotton fabric finished with β-cyclodextrin: Inclusion ability toward antimicrobial agent

β-Cyclodextrin was grafted onto cotton fabric through crosslinking with butane tetracarboxylic acid in presence of sodium hypophosphite monohydrate as a catalyst. This finished cotton fabric was loaded with the antimicrobial agent octenidine dihydrochloride. β-Cyclodextrin-grafted cotton fabrics, both after loading with octenidine dihydrochloride or before loading (control) were characterized for their antimicrobial activity against two types of bacteria (Gram positive and Gram negative) and two types of fungi, using the Diffusion Disk Method. The antimicrobial cotton fabric was subjected to several washing cycles and the antimicrobial activity was measured after each washing cycle to examine the durability of this antimicrobial finishing against repeated washing. The measurements showed that the finished cotton fabrics retain reasonable deal of their antimicrobial activity, even after 20 washing cycles. This long-lasting antimicrobial activity is attributed to the hosting ability of the cavities present in cyclodextrin moieties, which host the antimicrobial agent molecules and release them gradually.

MPC-polymer reduces adherence and biofilm formation by oral bacteria

Oral biofilms such as dental plaque cause dental caries and periodontitis, as well as aspiration pneumonia and infectious endocarditis by translocation. Hence, the suppression of oral biofilm formation is an issue of considerable importance. Mechanical removal, disinfectants, inhibition of polysaccharide formation, and artificial sugar have been used for the reduction of oral biofilm. From the viewpoint of the inhibition of bacterial adherence, we investigated whether aqueous biocompatible 2-methacryloyloxyethyl phosphorylcholine (MPC)-polymer can reduce streptococcal colonization and biofilm formation. We examined the effects of MPC-polymer on streptococcal adherence to saliva-coated hydroxyapatite and oral epithelial cells, and the adherence of Fusobacterium nucleatum to streptococcal biofilm. MPC-polymer application markedly inhibited both the adherence and biofilm formation of Streptococcus mutans on saliva-coated hydroxyapatite and streptococcal adherence to oral epithelial cells, and reduced the adherence of F. nucleatum to streptococcal biofilms. A small-scale clinical trial revealed that mouthrinsing with MPC-polymer inhibited the increase of oral bacterial numbers, especially of S. mutans. These findings suggest that MPC-polymer is a potent inhibitor of bacterial adherence and biofilm development, and may be useful to prevent dental-plaque-related diseases. (UMIN Clinical Trial Registry UMIN000003471).

Microbiological Evaluation of Octenidine Dihydrochloride Mouth Rinse after 5 Days' Use in Orthodontic Patients

Objective: To determine the absolute and relative antibacterial activity of octenidine dihydrochloride (OCT) against total and cariogenic bacteria in saliva samples of patients with fixed orthodontic appliances during 5 days of usage.

Materials and Methods: The study group consisted of 5 male and 13 female subjects who were selected from patients in the Clinic of Orthodontics. Each patient was given physiologic saline (PS), chlorhexidine gluconate (CHX), polyvinylpyrrolidone-iodine complex (PVP-I), and OCT every morning for 5 days, each separated by a 2-week interval. Total and cariogenic bacteria in saliva samples of orthodontically treated patients with fixed appliances were collected during 5 days of usage. Unstimulated saliva was collected as a baseline sample. Saliva samples were collected at 15 minutes, and on the second, third, and fifth day after rinsing the mouth with any of the solutions for 30 seconds, and bacterial counts were detected.

Results: OCT showed an ultimate reduction of total viable oral bacteria, Lactobacillus species, and Streptococcus mutans in vivo. OCT also had a significantly greater inhibitory effect than 0.2% CHX and 7.5% PVP-I, from the beginning of the study until the fifth day after the orthodontic appliances were bonded (P &lt; .1).

Conclusions: OCT compared favorably with respect to CHX and PVP-I complex in orthodontically treated patients with fixed appliances (P ≤ .1).