The effect of a SCN-/H2O2 toothpaste compared to a commercially available triclosan-containing toothpaste on oral hygiene and gingival health -- a 6-month home-use study

Antibacterial and antiplaque efficacy of a lactoperoxidase-thiocyanate-hydrogen-peroxide-system-containing lozenge

Background

Antimicrobial agents are considered valuable adjuncts to mechanical methods of plaque control. However, their long-term use can be limited because of side effects.

Therefore, using physiological substances is promising due to no risk of development, for example, of microbial resistances, allergies or DNA damaging. The lactoperoxidase-thiocyanate-hydrogen peroxide system (LPO-system) is a highly effective antimicrobial system. This study aimed to evaluate in a randomized study with a four-replicate cross-over design the effectiveness of two oral hygiene lozenges containing LPO-system in oral hygiene.

Results

After using the mouth rinse as positive control (A) and allocated test lozenges (B) (0.083% H₂O₂) & (C) (0.04% H₂O₂) for 4 days instead of the normal oral hygiene procedures (tooth brushing etc.), Listerine rinse (A) was statistically significantly more effective than the LPO-system-lozenge with 0.083% H₂O₂, the LPO-system-lozenge with 0.04% H₂O₂, and the placebo lozenge (D) in inhibiting plaque. Lozenges B and C were statistically significantly more effective than the placebo lozenge, but no statistically significant differences could be observed between them.

The LPO-system-lozenge (B) reduced statistically significantly more S. mutans than the LPO-system-lozenge with (C) and the placebo lozenge (D). The LPO-system-lozenge (C) reduced statistically significantly more Lactobacilli than Listerine (A), the LPO-system-lozenge (B) and the placebo lozenge (D). There were no statistically significant differences in the total CFUs between Listerine rinse, the LPO-system-lozenge with 0.083% H₂O₂ (B), the LPO-system-lozenge with 0.04% H₂O₂ (C), and the placebo lozenge (D). On day 5 there were no differences of the OSCN⁻-values between all A, B, C, and D. However, the SCN⁻-values increased over the days in both LPO-system-lozenges (B/C). The statistically significant differences between B/C and A/D on day 5 were as followed: A to B p = 0.0268; A to C p = 0.0035; B to D p = 0.0051; C to D p = 0.0007. Only in the group of Listerine (A) increased the NO₃⁻/NO₂⁻-quotient over the test time, which indicates a reduction of nitrate-reducing bacteria. On Day 5 the statistically significant difference between A and B was p = 0.0123.

Conclusions

The results indicate that lozenges containing a complete LPO-system, inhibiting plaque regrowth and reducing cariogenic bacteria, may be used in the daily oral hygiene.

Efficacy of adjunctive anti-plaque chemical agents in managing gingivitis: A systematic review and network meta-analyses

AIM

The aim of this network meta-analysis (NMA) was to compare the efficacy of different oral hygiene products for chemical biofilm control, in 6-month home-use, randomized clinical trials (RCTs), in terms of changes in gingival index (GI).

MATERIAL AND METHODS

Six-month RCTs assessing GI were identified and screened for inclusion. Relevant information was extracted, and quality and potential risk of bias were estimated. Mean differences between baseline and end were calculated to obtain standardized mean differences (SMDs). NMA protocols were applied to assess direct and indirect comparisons among products using Löe & Silness GI, modified GI and gingival severity index.

RESULTS

Fifty-three papers were included, 19 studies for mouth rinses, 32 for dentifrices, comprising data from 5,775 and 2,682 subjects, respectively. When ranking treatments, similar results were observed for all tested dentifrices, with the lowest effect observed for sanguinarine and baking soda. For mouth rinses, essential oils, triclosan-copolymer, chlorhexidine (at concentrations ≥ 0.10%) and cetylpyridinium chloride (>0.05%) demonstrated the greatest effect.

CONCLUSION

Although NMA revealed significant differences when comparing placebo versus some active agents, when comparing among active agents, no differences were found for dentifrices, while mouth rinses containing essential oils showed the greatest effect on GI scores.

The Significance of Lactoperoxidase System in Oral Health: Application and Efficacy in Oral Hygiene Products

Lactoperoxidase (LPO) present in saliva are an important element of the nonspecific immune response involved in maintaining oral health. The main role of this enzyme is to oxidize salivary thiocyanate ions (SCN^-) in the presence of hydrogen peroxide (H₂O₂) to products that exhibit antimicrobial activity. LPO derived from bovine milk has found an application in food, cosmetics, and medical industries due to its structural and functional similarity to the human enzyme. Oral hygiene products enriched with the LPO system constitute an alternative to the classic fluoride caries prophylaxis. This review describes the physiological role of human salivary lactoperoxidase and compares the results of clinical trials and in vitro studies of LPO alone and complex dentifrices enriched with bovine LPO. The role of reactivators and inhibitors of LPO is discussed together with the possibility of using nanoparticles to increase the stabilization and activity of this enzyme.

Efficacy of adjunctive anti-plaque chemical agents: a systematic review and network meta-analyses of the Turesky modification of the Quigley and Hein plaque index

AIM

The aim of this systematic review and network meta-analysis (NMA) was to compare the efficacy of different anti-plaque chemical agents, in 6-month, home-use, randomized clinical trials (RCTs), in terms of plaque index (PlI) changes.

MATERIAL AND METHODS

RCTs assessing PlI were identified, screened, and evaluated for inclusion. Relevant information was extracted, and quality and risk of bias were assessed. Mean differences between baseline-end were calculated to obtain weighted mean differences and 95% confidence intervals. NMA protocols were applied to assess direct and indirect comparisons among products using Turesky PlI.

RESULTS

Eighty-three papers were included: 49 examined dentifrices, 32 mouthrinses and 2 both. The NMA analysed 51 studies including data from 4242 and 4180 subjects for dentifrices and mouthrinses respectively. For dentifrices, triclosan-copolymer and chlorhexidine showed the greatest effect, with significant differences when compared with stannous fluoride. For mouthrinses, essential oils and chlorhexidine showed the greatest effect, with significant differences when compared with delmopinol, alexidine and cetylpyridinium chloride.

CONCLUSION

Within the limitations of this study (including the severe imbalance in the amount of evidence), dentifrices containing triclosan-copolymer or chlorhexidine and mouthrinses containing essential oils or chlorhexidine showed the greatest effect on PlI scores as assessed with NMA.

Estimation and correlation of salivary thiocyanate levels in healthy and different forms of tobacco users having chronic periodontitis: A cross-sectional biochemical study

BACKGROUND

Periodontitis is a common inflammatory disease with complex and multi-factorial origin. Tobacco usage has shown its adverse effect on periodontal health. Various components within saliva not only protect the integrity of oral tissues, but also provide clues to local and systemic diseases and conditions. Salivary thiocyanate (SCN) has been shown to be a chemical indicator in smokers and smokeless tobacco users. Noninvasive nature of salivary testing has made it an attractive and effective alternative to blood and urine testing. Limited studies are there comparing and correlating the salivary SCN levels in smokers with chronic periodontitis (CP). However, no studies show correlation of salivary SCN among gutka chewers with CP.

AIMS AND OBJECTIVES

The objective of the following study is to estimate, compare, and correlate the SCN levels in periodontally healthy, CP, smokers with CP and gutka chewers with CP subjects.

MATERIALS AND METHODS

Study includes 120 subjects with age 18-55 years, categorized as periodonally healthy (n = 30), CP (n = 30), smokers (n = 30), and gutka chewers (n = 30) with CP. Required clinical parameters such as gingival index, probing depth and clinical attachment loss were recorded and salivary SCN levels were estimated through ultraviolet-spectrophotometer.

RESULTS

Mean salivary SCN level were shown to be higher among smokers and gutka chewers with CP as compared to healthy and CP alone.

CONCLUSION

The present study exhibited the significant increase in salivary SCN levels among smokers and gutka chewers when compared to others, concluding that the analysis of salivary SCN levels could be used as an adjunctive means of diagnosis.

Triclosan inhibition of acute and chronic inflammatory gene pathways

AIM

We sought to determine whether triclosan (2,4,4'-trichloro-2'-hydroxydiphenylether), an extensively used anti-plaque agent with broad-spectrum anti-microbial activity, with reported anti-inflammatory effects via inhibition of prostaglandin E2 and interleukin 1 (IL-1)beta, could also more broadly suppress multiple inflammatory gene pathways responsible for the pathogenesis of gingivitis and periodontitis.

MATERIALS AND METHODS

As an exploratory study, the effects of triclosan on the inflammatory gene expression profile were assessed ex vivo using peripheral whole blood samples from eight periodontally healthy donors. Ten-millilitres whole blood aliquots were incubated 2 h with 0.3 microg/ml Escherichia coli lipopolysaccharide (LPS) with or without 0.5 microg/ml triclosan. Affymetrix microarray gene expression profiles from isolated leucocytes and pathway-specific quantitative polymerase chain reaction arrays were used to investigate changes in expression of target cytokines and cell signalling molecules.

RESULTS

Ex vivo human whole blood assays indicated that triclosan significantly down-regulated the LPS-stimulated expression of Toll-like receptor signalling molecules and other multiple inflammatory molecules including IL-1 and IL-6 and the dampening of signals that activate the T-helper type 1 acquired immune response via suppression of CD70 with concomitant up-regulation of growth factors related to bone morphogenetic protein (BMP)2 and BMP6 synthesis.

CONCLUSIONS

Anti-inflammatory effects were found in this exploratory survey, including suppression of microbial-pathogen recognition pathway molecules and the suppression of acute and chronic mediators of inflammation.

Effect of lactoperoxidase on the antimicrobial effectiveness of the thiocyanate hydrogen peroxide combination in a quantitative suspension test

BACKGROUND

The positive antimicrobial effects of increasing concentrations of thiocyanate (SCN-) and H2O2 on the human peroxidase defence system are well known. However, little is known about the quantitative efficacy of the human peroxidase thiocyanate H2O2 system regarding Streptococcus mutans and sanguinis, as well as Candida albicans. The aim of this study was to evaluate the effect of the enzyme lactoperoxidase on the bactericidal and fungicidal effectiveness of a thiocyanate-H2O2 combination above the physiological saliva level. To evaluate the optimal effectiveness curve, the exposure times were restricted to 1, 3, 5, and 15 min.

RESULTS

The bactericidal and fungicidal effects of lactoperoxidase on Streptococcus mutans and sanguinis and Candida albicans were evaluated by using two test mixtures of a 2.0% (w/v; 0.34 M) thiocyanate and 0.4% (w/v; 0.12 M) hydrogen peroxide solution, one without and one with lactoperoxidase. Following the quantitative suspension tests (EN 1040 and EN 1275), the growth of surviving bacteria and fungi in a nutrient broth was measured. The reduction factor in the suspension test without lactoperoxidase enzyme was < 1 for all three tested organisms. Thus, the mixtures of 2.0% (w/v; 0.34 M) thiocyanate and 0.4% (w/v; 0.12 M) hydrogen peroxide had no in vitro antimicrobial effect on Streptococcus mutans and sanguinis or Candida albicans. However, the suspension test with lactoperoxidase showed a high bactericidal and fungicidal effectiveness in vitro.

CONCLUSION

The tested thiocyanate and H2O2 mixtures showed no relevant antimicrobial effect. However, by adding lactoperoxidase enzyme, the mixtures became not only an effective bactericidal (Streptococcus mutans and sanguinis) but also a fungicidal (Candida albicans) agent.

Histologic evaluation of effect of thiocyanate topical application on hamster cheek pouch

The present study was conducted to investigate the effect of topical thiocyanate (SCN(-)) application on hamster cheek pouch mucosa. Sixty-six hamsters were divided into two groups. The test substance containing potassium thiocyanate was applied on the hamsters' cheek pouches at 55 mg/kg dosages. Cheek pouches were grossly examined after 12 weeks. Histometric evaluation included height measurements from the epithelium without stratum corneum, stratum corneum, and full epithelium. Clear cells frequency was compared between groups. Results were analyzed using Student's t test. The experimental group showed a lower height of the stratum corneum (p=0.035) and higher frequency of clear cells (p<0.001). There was no height difference for the epithelium without stratum corneum (p=0.677) and full epithelium (p=0.904) between groups. SCN(-) promotes no gross alterations on hamsters' cheek pouch and does not induce dysplastic features at the epithelium or inflammation at the connective tissue. The ion promotes histologic alterations on mucosa that need to be investigated in further studies.

Randomized controlled clinical trials on agents used for chemical plaque control

Taking into account the limitations of the daily self-performed oral hygiene the use of chemical agents that can be incorporated in dentifrice or mouth rinse formulations has been advocated. The present review deals with randomized controlled clinical trials of >or=6 months in duration, on the use of those agents and their effects on plaque and gingival inflammation.