Comparative evaluation of chlorhexidine varnish and fluoride varnish on plaque Streptococcus mutans count--an in vivo study

Effect of fluoride varnishes on oral bacteria of preschool children with cavitated and non-cavitated carious lesions: randomized clinical trial

We compare the effect of calcium and phosphate-containing sodium fluoride (NaF) varnishes to conventional NaF varnish on S. mutans and L. fermentum counts. 3-4 years old children were grouped according to their caries status (n = 45 each): caries-free, with non-cavitated and with cavitated lesions. Each group was randomly subdivided (n = 15 each) into: Group 1- 5% NaF, Group 2- 5% NaF with tricalcium phosphate, Group 3- 5% NaF with casein phosphopeptide- amorphous calcium phosphate. Biofilm and saliva were collected to quantify microorganisms at baseline (T1) and 24-months (T2). Differences between groups were compared using Kruskal-Wallis test, followed by Dunn-Bonferroni post-test, at 0.0167 α-level. Significant difference was found for percentage of children with detectable biofilm L. fermentum (p = 0.013) at T1 and salivary S. mutans (p = 0.011) at T2. Percentage of children increased from T1 to T2 in Group 2 with salivary S. mutans (p = 0.007), salivary L. fermentum (p = 0.035), and biofilm L. fermentum (p = 0.019) and in Group 3 with salivary L. fermentum (p = 0.035). Bacterial change was not significant in both samples of intervention groups, except increase in salivary S. mutans (p = 0.038) in Group 3. Both calcium- and phosphate-containing NaF varnishes demonstrated similar antibacterial effect on S. mutans and L. fermentum compared to conventional NaF varnish.

Biofilm formation following chitosan-based varnish or chlorhexidine-fluoride varnish application in patients undergoing fixed orthodontic treatment: a double blinded randomised controlled trial

Background

Orthodontic treatment poses an increased risk of plaque accumulation and demineralisation of enamel leading to white spot lesion around the brackets. This parallel arm trial aims to assess the degree of bacterial plaque formation adjacent to orthodontic brackets, following the application of a chitosan-based varnish or chlorhexidene-fluoride varnish.

Methods

A total of 200 teeth from 20 patients undergoing fixed orthodontic therapy were assessed and biofilm formation around the brackets were recorded using the Bonded Bracket Index (Plaque index) at baseline and weekly for 6 weeks. The bacterial count and plaque pH at corresponding weekly intervals were also recorded. Following bracket bonding, the patients were cluster randomised to receive chitosan-based varnish-CHS (UNO Gel Bioschell, Germiphene corp., Brantford, Canada) or chlorhexidine-fluoride varnish-CFV (Cervitec F, Ivoclar Vivadent, Schaan, Liechtenstein) every week on the representative teeth respectively. BBI proportions were compared between groups at all time intervals using Chi square test. Mean plaque bacterial count and plaque pH were compared using Mann Whitney U test and Tukey’s HSD test respectively.

Results

Baseline characteristics were similar between the groups: Mean age was CHS = 23 and CFV = 21; male to female ratio was CHS = 5/5, CFV = 7/3. At the end of 6 weeks, chitosan-based varnish performed equal to chlorhexidine-fluoride varnish (P > 0.05) with 98% and 95% of teeth with acceptable scores respectively. The plaque bacterial count significantly reduced at 6 weeks for both varnish compared to the baseline; The value for CHS was 0.43 ± 0.4 × 10⁴ and CFV was 0.77 ± 0.64 × 10⁴ CFU (P < 0.05), with no difference between both the varnishes. Both varnishes had no effect on the plaque pH that remained neutral.

Conclusion

This trial showed that both chitosan-based varnish and chlorhexidine-fluoride varnish reduced bacterial count, while the plaque pH remained neutral over a period of six weeks in patients undergoing fixed orthodontic therapy. The anti-plaque effects of the natural biopolymeric chitosan-based varnish was similar to that of chlorhexidine-fluoride varnish, a known chemotherapeutic agent.

Registration: This trial protocol was registered with https://www.ctri.nic.in (CTRI/2019/05/018896). (Date of registration 02/05/2019).

Protocol: The protocol was not published before trial commencement.

Effect of a chlorhexidine-encapsulated nanotube modified pit-and-fissure sealant on oral biofilm

The purpose of this study was to characterize a chlorhexidine-encapsulated nanotube modified pit-and-fissure sealant for biofilm development prevention. HS (commercial control); HNT (HS+15wt%Halloysite^®-clay-nanotube); CHX10% (HS+15wt% HNT-encapsulated with chlorhexidine 10%); and CHX20% (HS+15wt% HNT-encapsulated with CHX20%) were tested. Degree-of-conversion (DC%), Knoop hardness (KHN), and viscosity were analyzed. The ability of the sealant to wet the fissures was evaluated. Specimens were tested for zones of inhibition of microbial growth. S. mutans biofilm was tested by measuring recovered viability. Data were statistically analyzed (p<0.05). DC% was significantly higher for the HNT-CHX groups. For KHN, CHX10% presented a lower mean value than the other groups. Adding HNT resulted in higher viscosity values. The biofilm on CHX10% and CHX20% sealants presented remarkable CFU/mL reduction in comparison to the HS. The experimental material was able to reduce the biofilm development in S. mutans biofilm without compromising the sealant properties.

Inhibitory effects on Streptococcus mutans of antibacterial agents mixed with experimental fluoride varnish

We investigated the inhibitory effect of antibacterial agents mixed with experimental fluoride varnish (EFV) on Streptococcus mutans. The antibacterial agents used were (1 and 10) mM of xanthorrhizol, bakuchiol, bavachalcone, isobavachromene, and bavachromene. Agar diffusion tests were performed on S. mutans (1.1×10¹⁰ CFU/mL), using antibacterial agents without and with EFV. Bavachalcone showed the highest inhibition zone without and with EFV at both (1 and 10) mM (p<0.05). All EFV with antibacterial agents showed greater inhibition and semi-inhibition zones than EFV alone (p<0.05). The cell viability of each antibacterial agent was not significantly different from the vehicle controls (p>0.05), except xanthorrhizol and bakuchiol at 1 mM. All antibacterial agents were effective, while antibacterial agents with EFV co-formulations were more effective than EFV alone. Bavachalcone was the most effective agent against S. mutans, indicating its potential usefulness with fluoride varnish in preventing dental caries.

Effects of treatment with three types of varnish remineralizing agents on the microhardness of demineralized enamel surface

Background

Remineralization of incipient caries is one of the goals in dental health care ,especially in pediatric dentistry. The present study aimed at comparing the effects of MI varnish (3M (United states)) , Nano paste( FGM(Brezil) ), 5% sodium fluoride varnish) DuraphatColgate (united states) ) on remineralization of enamel lesions.

Material and Methods

In this in-vitrostudy, 60 intact human pre-molars, were randomly allocated to four groups of 15. Baseline surface microhardness in three points in the center of the polished area was measured. After two days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 under-went treatment with MI varnish, nano paste, 5% sodium fluoride varnish and then again microhardness was measured. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Bonfreni table was used.

Results

Duraphat varnish in comparison with control group, significantly increased surface microhardness and in comparison with Nano and MI paste varnish groups significant differences was shown between groups. (P< 0.05). MI paste varnish and Nano paste similary showed more increases in surface microhardness in comparison with Duraphat varnish and control groups (P≈1).

Conclusions

According to the results of this study, all three varnishes, Duraphat , MI paste and Nano paste increase the enamel surface microhardness and remineralization of incipient caries. MI paste and Nano paste compared to Duraphat Varnish, significantly showed more increases in enamel surface microhardness but Nano paste and MI paste were almost the same. Key words:CPP-ACP, Nano varnish, fluoride varnish, microhardness, demineralization, remineralization.

Effect of three different compositions of topical fluoride varnishes with and without prior oral prophylaxis on Streptococcus mutans count in biofilm samples of children aged 2-8 years: A randomized controlled trial

BACKGROUND

Various strategies for controlling caries focus on disrupting the interaction between risk factors. Of these, fluoride varnish has been shown to reduce the colony-forming (CFU) units and water-insoluble extracellular polysaccharide amount. Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and xylitol-containing fluoride varnishes have recently gained importance as caries-protective fluoride varnishes.

AIM

This study aims to assess and compare the reduction in Streptococcus mutans count in biofilm samples after topical application of three different fluoride varnishes and to evaluate the effect of oral prophylaxis prior to fluoride varnish application.

MATERIALS AND METHODS

Sixty healthy children with no active caries, in the age group of 2-8 years, were randomly divided into Group A = fluoride varnish containing CPP-ACP; Group B = fluoride varnish containing xylitol; and Group C = fluoride varnish with 0.9% difluorosilane; further, the groups were divided into two subgroups, namely A1, B1, and C1 with prior oral prophylaxis and A2, B2, and C2 without oral prophylaxis. Plaque samples were collected at baseline, 1^st month, and 3^rd month; cultured; and incubated, and CFU/ml was calculated.

RESULTS

Data were compiled, and CFU/ml was analyzed by independent t-test, paired t-test, and one-way ANOVA. There was no statistical difference between the fluoride groups. Furthermore, no statistically significant difference was seen between the subgroups.

CONCLUSION

Fluoride varnish containing CPP-ACP showed higher reduction in S. mutans count followed by xylitol-containing fluoride varnish and Fluor Protector^®. There was no effect of prior oral prophylaxis on the efficacy of fluoride varnish.

Iowa nursing facility oral hygiene (INFOH) intervention: A clinical and microbiological pilot randomized trial

PURPOSE/AIM

The aim of this pilot study was to evaluate feasibility and gather initial data for a definitive study to test the clinical and microbiological effectiveness of a nursing facility (NF) customized oral hygiene protocol, intended to be delivered by dental hygienists and NF personnel.

MATERIALS AND METHODS

A convenience sample of 8 Eastern Iowa NFs was recruited, and each NF was assigned to one of three intervention groups: (1) control (current oral hygiene practice), (2) educational program only, and (3) educational program plus 1% chlorhexidine varnish monthly application. Demographic information, systemic health data, patient centered data, oral health data, and microbiology samples were collected at baseline and after 6 months.

RESULTS

Recruitment response rates were 21% for NFs and 23% for residents. A total of 81 residents were examined at baseline and of those, 49 were examined at 6 months (39.5% attrition). There were no statistically or clinically significant differences among the intervention groups at 6 months for any of the recorded clinical or microbiological outcomes.

CONCLUSIONS

Recruitment and retention posed a significant challenge to this trial, even with a relatively short observation period. Results from this pilot study did not encourage further investigation of this customized oral hygiene protocol.

Effect of a chlorhexidine/thymol and a fluoride varnish on caries development in erupting permanent molars: a comparative study

AIM

To compare the caries preventive effect of a chlorhexidine/thymol-containing antibacterial varnish with a fluoride varnish when topically applied during the eruption of permanent molars.

METHODS

The study group consisted of 189 patients, 5-14 years of age, with one 1st or 2nd permanent molar in the process of eruption. After stratification for type of molar and stage of eruption, the patients were randomised to either quarterly topical applications with an antibacterial varnish (Cervitec(®) Plus; CV group) or biannual applications with a fluoride varnish plus biannual treatments with placebo varnish (Fluor Protector; FV group). The duration of the study was 2 years. The primary endpoint was caries incidence (initial and cavitated) in the erupting molars and the secondary outcome was salivary mutans streptococci (MS) counts.

RESULTS

The groups were balanced with respect to socio-economy, oral hygiene, dietary habits and caries experience at baseline. The dropout rate was 11.6 %. The caries incidence was low (< 10 %) in both groups and there was no significant difference between the CV and FV groups with respect to occlusal caries development in the erupting molars (relative risk 1.08, 95 % CI 0.94-1.25). Significantly lower levels of salivary MS were disclosed in the CV group at the end of the study (p < 0.05).

CONCLUSIONS

No difference in occlusal caries development in young permanent molars was displayed after topical applications of either a chlorhexidine/thymol varnish or a fluoride varnish during tooth eruption.

Inhibited biofilm formation and improved antibacterial activity of a novel nanoemulsion against cariogenic Streptococcus mutans in vitro and in vivo

The aim of this study was to prepare a novel nanoemulsion loaded with poorly water-soluble chlorhexidine acetate (CNE) to improve its solubility, and specifically enhance the antimicrobial activity against Streptococcus mutans in vitro and in vivo. In this study, a novel CNE nanoemulsion with an average size of 63.13 nm and zeta potential of −67.13 mV comprising 0.5% CNE, 19.2% Tween 80, 4.8% propylene glycol, and 6% isopropyl myristate was prepared by the phase inversion method. Important characteristics such as the content, size, zeta potential, and pH value of CNE did not change markedly, stored at room temperature for 1 year. Also, compared with chlorhexidine acetate water solution (CHX), the release profile results show that the CNE has visibly delayed releasing effect in both phosphate-buffered saline and artificial saliva solutions (P<0.005). The minimum inhibitory concentration and minimum bactericidal concentration of CHX for S. mutans (both 0.8 μg/mL) are both two times those of CNE (0.4 μg/mL). Besides, CNE of 0.8 μg/mL exhibited fast-acting bactericidal efficacy against S. mutans, causing 95.07% death within 5 minutes, compared to CHX (73.33%) (P<0.01). We observed that 5 mg/mL and 2 mg/mL CNE were both superior to CHX, significantly reducing oral S. mutans numbers and reducing the severity of carious lesions in Sprague Dawley rats (P<0.05), in an in vivo test. CNE treatment at a concentration of 0.2 μg/mL inhibited biofilm formation more effectively than CHX, as indicated by the crystal violet staining method, scanning electron microscopy, and atomic force microscopy. The cell membrane of S. mutans was also severely disrupted by 0.2 μg/mL CNE, as indicated by transmission electron microscopy. These results demonstrated that CNE greatly improved the solubility and antimicrobial activity of this agent against S. mutans both in vitro and in vivo. This novel nanoemulsion is a promising medicine for preventing and curing dental caries.

Propolis--based chitosan varnish: drug delivery, controlled release and antimicrobial activity against oral pathogen bacteria

Background

Dental caries is the most prevalent oral disease in several Asian and Latin American countries. It is an infectious disease and different types of bacteria are involved in the process. Synthetic antimicrobials are used against this disease; however, many of these substances cause unwarranted undesirable effects like vomiting, diarrhea and tooth staining. Propolis, a resinous substance collected by honeybees, has been used to control the oral microbiota. So, the objective of this study was to develop and characterize sustained-release propolis-based chitosan varnish useful on dental cariogenic biofilm prevention, besides the in vitro antimicrobial activity.

Methods

Three formulations of propolis - based chitosan varnish (PCV) containing different concentrations (5%, 10% and 15%) were produced by dissolution of propolis with chitosan on hydro-alcoholic vehicle. Bovine teeth were used for testing adhesion of coatings and to observe the controlled release of propolis associated with varnish. It was characterized by infrared spectroscopy, scanning electron microscopy, casting time, diffusion test in vitro antimicrobial activity and controlled release. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were tested for the main microorganisms involved in the cariogenic biofilm through the microdilution test in 96-well plates.

Results

The formulations presented a tooth surface adherence and were able to form films very fast on bovine tooth surface. Also, propolis-based chitosan varnishes have shown antimicrobial activity similar to or better than chlorhexidine varnish against all oral pathogen bacteria. All microorganisms were sensitive to propolis varnish and chitosan. MIC and MBC for microorganisms of cariogenic biofilme showed better results than chlorhexidine. Propolis active components were released for more than one week.

Conclusion

All developed formulations turn them, 5%, 10% and 15% propolis content varnish, into products suitable for clinical application on dental caries prevention field, deserving clinical studies to confirm its in vivo activity.

Antibacterial action of Chlorhexidine/thymol containing varnishes in vitro and in vivo

OBJECTIVES

The antibacterial activity of two different formulations of a chlorhexidine/thymol varnish should be elucidated in vitro and in vivo.

METHODS

The agar diffusion assay with Cervitec(®) and CervitecPlus(®) and three reference strains each of streptococci, lactobacilli, actinomyces and periodontal pathogens was performed. In a split-mouth study, 40 volunteers applied the test (CervitecPlus(®), solvent water and ethanol) and control (Cervitec(®), solvent ethyl acetate) varnish at buccal recessions of premolar teeth at baseline as well as after two, four and seven days. Supra- and subgingival plaques were collected 2 weeks before baseline and at the screening appointments. Supragingival plaque was analysed for mutans streptococci and lactobacilli and subgingival samples for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Porphyromonas intermedia. Friedman/Wilcoxon tests and U-test were used for statistical analysis (P < 0.05).

RESULTS

Most reference strains were susceptible with inhibition zones (mm) as follows: Cervitec(®)/CervitecPlus(®) streptococci 27 ± 1.7/21.3 ± 2.5, lactobacilli 26 ± 9.2/23.7 ± 4.9, actinomyces 36.3 ± 6.6/27.3 ± 1.5, periodontal pathogens 18.7 ± 7.6/18 ± 1.7. Both varnishes reduced significantly the counts of mutans streptococci and lactobacilli in the patients. However, no significant differences were found between test and control sides at any time. The total counts of periodontal pathogens were low. A tendency to higher counts of A. actinomycetemcomitans at the control side could be shown; the test side did not harbour significantly higher counts.

CONCLUSION

Both varnishes may influence the plaque formation and reduce mutans streptococci in supragingival plaque.