The effect of a toothpaste containing 2% zinc citrate and 0.3% Triclosan on bacterial viability and plaque growth in vivo compared to a toothpaste containing 0.3% Triclosan and 2% copolymer

Investigation of the constituents of commercially available toothpastes

OBJECTIVES

Toothpaste plays a pivotal role in oral and dental hygiene. This cross-sectional study not only investigates the constituents of toothpastes available in the market and their frequency across different brands but also delves into the potential side effects, irritations, or unfavourable outcomes of these constituents, emphasizing the broader health and environmental implications.

METHODS

The largest of the five major chain markets in each district of Istanbul was visited, and adult toothpastes were included in this study. All the constituents that make up the toothpaste were individually recorded in an Excel database. Subsequently, literature regarding the purposes, toxic and potential side effects of each ingredient was gathered using databases such as Google Scholar, PubMed and ScienceDirect. The percentages of these ingredients' occurrence among all the toothpastes were calculated, and the ingredients were categorized into 15 distinct groups based on their usage purposes.

RESULTS

There were 160 different varieties of toothpaste belonging to 19 different brands on the market shelves. Although a total of 244 different ingredients were identified, only 78 of them were included in the study. Among the analysed toothpaste types, 105 of them were found to contain 1450 ppm fluoride, whilst 26 toothpaste variants were discovered to have fluoride levels below this value. Among the various ingredients analysed, particular attention was drawn to commonly debated compounds in oral care products. Specifically, titanium dioxide was found in 68% (n = 111) of the varieties, sodium lauryl sulphate in 67% (n = 108) and paraben in 2% (n = 4), respectively.

CONCLUSION

Whilst certain ingredients may raise concerns for potential side effects and health considerations within the human body, the toothpaste has long been regarded as an indispensable tool for maintaining optimal oral and dental health. However, gaining a deeper understanding and conducting research on each constituent that comprises the toothpaste, as well as raising awareness in this regard, holds significant importance for human health.

The effect of active oxygen-containing toothpaste on Streptococcus mutans and white spot lesions: An in-vivo randomized controlled trial

INTRODUCTION

Fixed appliances limit patients' ability to clean their teeth, thus making orthodontic patients highly susceptible to developing white spot lesions (WSLs). Using patient compliance would be one of the simplest methods to prevent WSLs.

METHODS

A parallel trial design with 34 patients that met the eligibility criteria were randomized to experimental (received Blue M oxygen for health toothpaste) and control (received Colgate Total fluoridated toothpaste) groups. The eligibility criteria were that the patients should be aged 13-30 years, on fixed mechanotherapy, had undergone therapeutic extraction of all first premolars, had completed leveling and aligning, and had satisfactory oral hygiene (assessed using pretreatment and current Simplified Oral Hygiene Index scores). The objectives were to assess the effects of active oxygen-containing toothpaste on Streptococcus mutans (SM) and WSLs in patients undergoing fixed mechanotherapy. The random allocation sequence was generated using the RAND function in Microsoft Excel. The sequence generated was sealed in opaque white envelopes. The investigators and the participants were blinded until allocation. Blinding of the first author (J.A.G.) who dispensed the toothpaste or the participants was not possible. The outcome assessment was blinded by coding the plaque specimens sent for real-time polymerase chain reaction (RT-PCR) to ensure that the final data assessment was blinded. The study setting was the Department of Orthodontics and Dentofacial Orthopedics, Sri Ramachandra Institute of Higher Education and Research (SRIHER) University. The primary outcome was SM counts, which were analyzed using RT-PCR. The secondary outcome was WSL assessment, performed using DIAGNOdent and International Caries Detection and Assessment System (ICDAS) II criteria at baseline and after 4 weeks. The data were subjected to statistical analysis.

RESULTS

Thirty-four patients were randomized to 17 per group and analyzed. RT-PCR showed lower SM in the experimental group (Ct = 32.25 ± 10.6) than in the control group (Ct = 30.9 ± 10.49). However, this was not statistically significant (P = 0.70). ICDAS scores remained the same from baseline and after 4 weeks for both groups. The DIAGNOdent values were in tandem with the ICDAS scores and showed minimal change for the 2 groups (P >0.05). A strong positive correlation was observed for DIAGNOdent and ICDAS scores (τb >0.30). No harms or adverse effects were observed or reported by the patients during the experimental period.

CONCLUSIONS

The active oxygen-containing toothpaste showed a greater inhibitory effect on SM than the fluoridated toothpaste. However, this effect was minimal. Both kinds of toothpaste showed negligible effects on WSLs. Thus, active oxygen-containing toothpaste is as effective as fluoridated toothpaste.

REGISTRATION

The Trial was registered in the Controlled Trials Registry India (CTRI/2021/10/037458).

PROTOCOL

The full protocol can be obtained from any of the authors via e-mail.

FUNDING

The project was self-funded.

A randomized clinical study to examine the oral hygiene efficacy of a novel herbal toothpaste with zinc over a 6-month period

OBJECTIVES

This clinical investigation examined the effects of brushing with a test toothpaste containing natural ingredients, that is, clove (Syzgium Aromaticum), aloe vera (Aloe Barbadensis), amla (Emblica Officinalis), neem (Azadirachta Indica), tulsi (Ocimum Basillicum) and honey (from Apis Mellifera) along with zinc salts and fluoride in comparison with a dentifrice formulated with fluoride alone on dental plaque and gingivitis over a 6-month period.

MATERIALS AND METHOD

One hundred and eighty (180) subjects with mean plaque index scores greater than 1.5 (Turesky Modified Quigley Hein Plaque Index) and gingival index scores >1.0 (Loe and Silness gingival index) in good general health and who met other study criteria were enrolled in the clinical study. Subjects were evaluated for plaque and gingival index scores and were randomly assigned to perform twice-daily oral hygiene with either the test or the control toothpaste for the next 6 months. One hundred and fifty (150) subjects [test toothpaste (n = 72) and control toothpaste (n = 78)] completed the 6-month clinical study with evaluable data. Post-treatment assessments identical to baseline were conducted after 3-month and 6-month use of an assigned product after subjects refrained from oral hygiene for 12 h prior to each evaluation. Comparisons of the treatment groups with respect to baseline-adjusted gingival, plaque, and bleeding index scores at the follow-up examinations were performed using analyses of covariance (ANCOVA). All statistical tests of hypotheses were two-sided and employed a level of significance of p < 0.05.

RESULTS

No significant intergroup differences were noted between treatment groups for age and gender by two-sample t-test and chi-square analyses, respectively (p > 0.05). Furthermore, the treatment groups demonstrated no differences at baseline for plaque, gingival and bleeding index scores by a two-sample t-test (p > 0.05). At 3-month and 6-month examination, the test toothpaste exhibited progressive reductions in plaque, gingival and bleeding scores as compared to control toothpaste as showed by ANCOVA (p < 0.001). In comparison with the control, the test demonstrated reductions in 23.5%, 25.6%, and 73.3% for dental plaque, gingival index and bleeding index outcomes, respectively, at the final visit. Reductions in the frequencies of sites with higher clinical scores were noted over the study with more sites registering improvements in the test group than in the control group.

CONCLUSIONS

Routine oral hygiene with the test toothpaste formulated with herbal ingredients and zinc demonstrated a clinical adjunctive improvement in oral hygiene and parameters of gingival health as compared to brushing with a fluoride toothpaste.

An investigation of the antibacterial ability and cytotoxicity of a novel cu-bearing 317L stainless steel

In order to solve the challenging problem of microbial infections caused by microorganisms on medical implants, it is imperative to develop novel antimicrobial biomaterials. This work demonstrated that 317L-Cu stainless steel (SS), created by adding copper through a solution and aging heat treatment process, exhibited good antibacterial properties against staphylococcus aureus, achieving 2 log reduction of planktonic cells after 5 days of incubation. In this study, the antibacterial test was performed using the plate count method, the fluorescence cell staining method and the quantitative polymerase chain reaction (qPCR) method. It is well known that a high concentration of copper ion can lead to cytotoxicity. This work explored the cytotoxicity of 317L-Cu SS through real-time cell analysis (RTCA). Experimental results demonstrated that the 317L-Cu SS possessed a satisfactory antibacterial ability against S. aureus, and the antibacterial rate based on the reduction of sessile cell count reached 98.3% after 24-hour treatment. The bacterial adhesion and the biofilm thickness were considerably reduced by the 317L-Cu SS. The results of RTCA suggested that 317L-Cu SS did not introduce cytotoxicity to mouse cells, indicating its suitability as a medical implant material.

Physical chemical effects of zinc on in vitro enamel demineralization

OBJECTIVES

Zinc salts are formulated into oral health products as antibacterial agents, yet their interaction with enamel is not clearly understood. The aim was to investigate the effect of zinc concentration [Zn(2+)] on the in vitro demineralization of enamel during exposure to caries-simulating conditions. Furthermore, the possible mechanism of zinc's action for reducing demineralization was determined.

METHODS

Enamel blocks and synthetic hydroxyapatite (HAp) were demineralized in a range of zinc-containing acidic solutions (0-3565ppm [Zn(2+)]) at pH 4.0 and 37°C. Inductively coupled-plasma optical emission spectroscopy (ICP-OES) was used to measure ion release into solution. Enamel blocks were analysed by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), and HAp by X-ray diffraction (XRD) and neutron diffraction (ND).

RESULTS

ICP-OES analysis of the acidic solutions showed a decrease in [Ca(2+)] and [PO4(3-)] release with increasing [Zn(2+)]. FTIR revealed a α-hopeite (α-Zn3(PO4)2.4H2O)-like phase on the enamel surfaces at >107ppm [Zn(2+)]. XRD and ND analysis confirmed a zinc-phosphate phase present alongside the HAp.

CONCLUSIONS

This study confirms that zinc reduces enamel demineralization. Under the conditions studied, zinc acts predominantly on enamel surfaces at PO4(3-) sites in the HAp lattice to possibly form an α-hopeite-like phase.

CLINICAL SIGNIFICANCE

These results have a significant implication on the understanding of the fundamental chemistry of zinc in toothpastes and demonstrate its therapeutic potential in preventing tooth mineral loss.

Anti-gingivitis effect of a dentifrice containing bioactive glass (NovaMin) particulate

BACKGROUND

The objective of this pilot clinical trial was to evaluate the anti-gingivitis and anti-plaque effects of a dentifrice containing bioactive glass (NovaMin) compared with a placebo control dentifrice in a 6 weeks clinical study.

METHODS

The study design was a randomized, double-blinded, controlled clinical trial. One hundred volunteers took part in the study and were matched for plaque index (PLI), gingival bleeding index (GBI), age and gender. The protocol was reviewed and approved by the Ethical Committee of the University. The subjects received a supragingival prophylaxis to remove all plaque, calculus and extrinsic stain. Following the baseline examination, subjects were instructed to brush with their assigned dentifrice and toothbrush. The PLI and GBI were determined for the baseline and 6 weeks. The data were analysed using a repeated-measures anova conducted on the two dependent measures to compare the effect between the test and control group.

RESULTS

Ninety-five subjects finished the study. The results showed that the PLI (baseline=1.54, 6 weeks=1.29) and GBI (baseline=1.14, 6 weeks=0.47) were significantly reduced, respectively, over the 6 weeks period in the test group (p<0.001 for each measure). There was a 58.8% reduction in gingival bleeding and a 16.4% reduction in plaque growth. There was no difference of the PLI (baseline=1.60, 6 weeks=1.57) and GBI (baseline=1.18, 6-week=1.02) over the 6 week period in the control group.

CONCLUSION

This study demonstrated that a dentifrice containing NovaMin significantly improves oral health as measured by a reduction in gingival bleeding and reduction in supragingival plaque compared with a negative dentifrice over the 6 weeks study period.

Transport and metabolism of citrate by Streptococcus mutans

Streptococcus mutans, a normal inhabitant of dental plaque, is considered a primary etiological agent of dental caries. Two virulence determinants of S. mutans are its acidogenicity and aciduricity (the ability to produce acid and the ability to survive and grow at low pH, respectively). Citric acid is ubiquitous in nature; it is a component of fruit juices, bones, and teeth. In lactic acid bacteria citrate transport has been linked to increased survival in acidic conditions. We identified putative citrate transport and metabolism genes in S. mutans, which led us to investigate citrate transport and metabolism. Our goals in this study were to determine the mechanisms of citrate transport and metabolism in S. mutans and to examine whether citrate modulates S. mutans aciduricity. Radiolabeled citrate was used during citrate transport to identify citrate metal ion cofactors, and thin-layer chromatography was used to identify metabolic end products of citrate metabolism. S. mutans was grown in medium MM4 with different citrate concentrations and pH values, and the effects on the growth rate and cell survival were monitored. Intracellular citrate inhibited the growth of the bacteria, especially at low pH. The most effective cofactor for citrate uptake by S. mutans was Fe(3+). The metabolic end product of citrate metabolism was aspartate, and a citrate transporter mutant was more citrate tolerant than the parent.

The oral environment: the challenge for antimicrobials in oral care products

For any antibacterial/ anti-plaque system from an oral care product to be effective, it must firstly be delivered and retained at relevant sites in the oral cavity and secondly, remain active within the chosen formulation to successfully target the biofilm cells within dental plaque. This must include inhibition of the growth and metabolism of relevant organisms associated with disease. This review will concentrate on understanding the environmental conditions in which such oral care products must work and summarise the activity within the oral cavity of the main antibacterial and anti-plaque agents in common oral care products, namely chlorhexidine, essential oils, metal salts and Triclosan. Routes to further enhance the activity of these products, together with the use of relatively novel formats such as confectionery products to provide added consumer oral health benefits will be considered.