The effect of soluble pyrophosphates on dental calculus in adults

Assessment of the capacity of a pyrophosphate-based mouth rinse to inhibit the formation of supragingival dental calculus. A randomized double-blind placebo-controlled clinical trial

Background

This study aimed to analyze the efficacy of an anti-calculus mouth rinse and its possible adverse effects on the mucosa and teeth.

Material and Methods

This randomized double-blind placebo-controlled clinical trial included 40 patients with treated and managed periodontal disease, all with a history of rapid calculus formation. Patients used a pyrophosphate-based test mouth rinse (B) or a placebo (A). A range of parameters were measured for: saliva (saliva flow, pH and chemical composition); calculus (Volpe-Manhold [V-M] index, weight, and volume); adverse effects on mucosa and teeth; and the patients’ subjective perceptive of mouth rinse efficacy.

Results

The test mouth rinse B produced reductions in urea, uric acid, and phosphorous, calcium, saliva flow, and increases in pH. V-M index and calculus weight decreased after using the test mouth rinse. Calculus volume decreased with both mouth rinses. No changes to the mucosa or teeth were observed. Patients perceived that the test mouth rinse was more effective.

Conclusions

The test/B and placebo mouth rinses both modified certain parameters in saliva composition, particularly reductions in urea, uric acid, and phosphorous. Calcium tended to increase after using the test-B mouth rinse. The results did not demonstrate the anticalculus efficacy of the pyrophosphate-based mouth rinse or positive effects on saliva flow or composition. This field requires further research, as no product has been developed that prevents calculus formation completely.

Key words:Dental calculus, anticalculus mouth rinse, Volpe Manhold index.

A randomized controlled clinical study of the effect of daily intake of Ascophyllum nodosum alga on calculus, plaque, and gingivitis

OBJECTIVE

The aim of this study is to evaluate, in a randomized controlled cross-over study, the effect of daily intake of the alga Ascophyllum nodosum on supragingival calculus, plaque formation, and gingival health over a 6-month period.

MATERIAL AND METHODS

Sixty-one adults with moderate to heavy calculus formation since their last yearly recall visit participated. In a randomized order over two 6-month periods, they swallowed two capsules daily, comprising a total of 500 mg dried marine alga powder (Ascophyllum nodosum, ProDen PlaqueOff®) or two negative control tablets. During the study, the participants maintained their regular oral habits. Their teeth were professionally cleaned at the start of each period and after the 6-month registrations. A wash out period of 1 month separated the two 6-month periods. Supragingival calculus (Volpe Manhold), gingivitis (Löe and Silness), gingival bleeding (Ainamo and Bay), and plaque (Quigley-Hein) were registered at screening and at the end of the two periods. Differences in oral health between the test and control periods were analyzed using a paired t test and Wilcoxon signed rank test.

RESULTS

Fifty-five participants completed the study. After the alga intake, the mean calculus reduction was 52% compared to the control (p < 0.0001). Fifty-two participants showed less calculus formation in the alga group than in the control group. Plaque (p = 0.008) and gingival bleeding (p = 0.02) were also significantly less in the alga group. However, no significant difference was found between the groups for gingivitis (p = 0.13).

CONCLUSIONS

The alga intake significantly reduced the formation of supragingival calculus and plaque and occurrence of gingival bleeding. The alga has a systemic effect on oral health.

CLINICAL RELEVANCE

Daily intake of the alga Ascophyllum nodosum as an adjunct to customary oral hygiene showed a major reduction of supragingival calculus formation and reduced plaque formation. In addition, the calculus in the alga group was characterized by a more porous and less solid structure and was easier to remove than the calculus in the control group.

Phosphate: known and potential roles during development and regeneration of teeth and supporting structures

Inorganic phosphate (P(i)) is abundant in cells and tissues as an important component of nucleic acids and phospholipids, a source of high-energy bonds in nucleoside triphosphates, a substrate for kinases and phosphatases, and a regulator of intracellular signaling. The majority of the body's P(i) exists in the mineralized matrix of bones and teeth. Systemic P(i) metabolism is regulated by a cast of hormones, phosphatonins, and other factors via the bone-kidney-intestine axis. Mineralization in bones and teeth is in turn affected by homeostasis of P(i) and inorganic pyrophosphate (PPi), with further regulation of the P(i)/PP(i) ratio by cellular enzymes and transporters. Much has been learned by analyzing the molecular basis for changes in mineralized tissue development in mutant and knock-out mice with altered P(i) metabolism. This review focuses on factors regulating systemic and local P(i) homeostasis and their known and putative effects on the hard tissues of the oral cavity. By understanding the role of P(i) metabolism in the development and maintenance of the oral mineralized tissues, it will be possible to develop improved regenerative approaches.

Efficacy and mechanisms of non-antibacterial, chemical plaque control by dentifrices--an in vitro study

OBJECTIVES

The provision of antiplaque benefits to dentifrices assists patients in improving hygiene and reducing susceptibility to gingivitis and caries. Chemical plaque control involves different mechanisms and is mostly associated with antibacterial effects, but also includes effects on pellicle surface chemistry to improve cleansing or discourage renewed plaque formation. It is the aim of this paper to analyze in vitro detachment of co-aggregating oral actinomyces and streptococci from pellicle surfaces by dentifrice supernates and to study subsequent de novo streptococcal deposition.

METHODS

Detachment by dentifrices of a co-adhering bacterial pair was studied in the parallel plate flow chamber on a 16 h pellicle coated surface. After detachment by perfusing the chamber with a dentifrice, re-deposition was initiated by flowing with a fresh streptococcal suspension. The dentifrices included both a regular, SLS-fluoride based formulation as well a pyrophosphate, anticalculus and antimicrobial formulations.

RESULTS

All dentifrice supernates containing SLS were effective in detaching co-adhering bacteria from pellicles surfaces, except in combination with SnF(2). When hexametaphosphate was added immediate detachment was relatively low, but continued even during re-deposition. The re-deposition of streptococci after detachment by other, NaF containing dentifrices involved relatively few large aggregates, presumably because fluoride was able to block bi-dentate calcium binding sites on the bacterial cell surfaces, mediating co-adhesion. When pyrophosphate was present in addition to NaF, re-deposition involved significantly more large aggregates, likely because pyrophosphate served as a bi-dentate bridge between calcium bound on the bacterial cell surfaces.

CONCLUSION

Commercially available dentifrice formulations differ in their ability to stimulate bacterial detachment from pellicles and dependent on their composition yield the formation of large co-adhering aggregates of actinomyces and streptococci in de novo deposition.

Supragingival calculus: formation and control

Dental calculus is composed of inorganic components and organic matrix. Brushite, dicalcium phosphate dihydrate, octacalcium phosphate, hydroxyapatite, and whitlockite form the mineral part of dental calculus. Salivary proteins selectively adsorb on the tooth surface to form an acquired pellicle. It is followed by the adherence of various oral micro-organisms. Fimbriae, flagella, and some other surface proteins are essential for microbial adherence. Microbial co-aggregation and co-adhesion enable some micro-organisms, which are incapable of adhering, to adhere to the pellicle-coated tooth surface. Once organisms attach to the tooth surface, new genes could be expressed so that mature dental plaque can form and biofilm bacteria assume increased resistance to antimicrobial agents. Supersaturation of saliva and plaque fluid with respect to calcium phosphates is the driving force for plaque mineralization. Both salivary flow rate and plaque pH appear to influence the saturation degree of calcium phosphates. Acidic phospholipids and specific proteolipids present in cell membranes play a key role in microbial mineralization. The roles of crystal growth inhibitors, promoters, and organic acids in calculus formation are discussed. Application of biofilm culture systems in plaque mineralization is concisely reviewed. Anti-calculus agents used--centering on triclosan plus polyvinyl methyl ether/maleic acid copolymer, pyrophosphate plus polyvinyl methyl ether/maleic acid copolymer, and zinc ion-in commercial dentifrices are also discussed in this paper.

Factors contributing to adverse soft tissue reactions due to the use of tartar control toothpastes: report of a case and literature review

Tetrasodium and/or tetrapotassium pyrophosphate (Ppi) is the anticalculus component of most tartar control dentifrices on the market today. While pyrophosphates alone are not responsible for hypersensitivity reactions, several modifications which may lead to adverse oral manifestations may occur when pyrophosphates are added to a dentifrice. First, tetrasodium pyrophosphate in a dentifrice forms a slightly alkaline solution upon oral use which could irritate oral membranes. Second, increased concentrations of flavoring agents, known to be sensitizers, are needed to mask the strong bitter taste of pyrophosphates. Third, increased concentrations of detergents, capable of producing hypersensitivity reactions, are necessary to allow the pyrophosphates to become soluble in the dentifrice. Fourth, a pre-existing condition of reduced salivary flow may augment hypersensitivity to tartar control toothpastes. While pyrophosphates have been approved as additives in dentifrices, these compounds along with the increased concentrations of flavorings and detergents and their higher intraoral alkalinity are strongly implicated as the causative factor in certain hypersensitivity reactions.

Control of supragingival calculus. Scaling and polishing and anticalculus toothpastes: an opinion

The removal of supragingival calculus by scaling and polishing of the teeth is only one aspect of a dental prophylaxis. However in many countries, a large number of individuals only require and receive, at regular intervals, a supragingival scale and polish. The association of supragingival calculus to gingival and periodontal disease is unclear, however, it is logical to assume a plaque retention role. Moreover, for the individual, supragingival calculus may pose cosmetic problems. Regular calculus removal is both time consuming and exacting for dental professionals and has important financial implications to patients and/or health schemes. The benefits of regular supragingival calculus removal are not established, yet potential detrimental effects for the patient are known, and certain groups are susceptible to systemic disease consequent on scaling and polishing of the teeth. The oral hygiene habits of most individuals appear insufficient to prevent the reformation of supragingival calculus once removed and for this reason chemical inhibition is an attractive proposition. Most success to date has been with agents which inhibit crystal growth, notably pyrophosphates, and toothpaste products are available containing such agents. Clinical studies support efficacy for some products and indicate that the magnitude of calculus inhibition would reduce the need for or frequency of scaling and polishing of teeth in a proportion of individuals. Anticalculus toothpastes would appear to be proven worthy of recommendation for those individuals in whom supragingival calculus formation is a problem.

Growth-inhibitory effect of pyrophosphate on oral bacteria

The purpose of this investigation was to determine whether pyrophosphate, the anticalculus component of tartar-control dentifrices, exerts antimicrobial activity against oral bacteria commonly found in supragingival plaque. Minimal inhibitory concentrations of pyrophosphate were determined for Streptococcus sanguis, Streptococcus mutans (serotype c), Actinomyces viscosus and Actinomyces naeslundii. All of the bacteria tested were susceptible to pyrophosphate with identical minimal inhibitory concentrations of 0.67% wt/vol (25 mM). Bactericidal kinetics assays revealed that both S. mutans and A. viscosus were killed by pyrophosphate, with the latter being considerably more susceptible. The mechanism of killing was not due to high ionic strength, as comparable controls showed no loss in numbers of viable cells. Brief exposure (two 5-min incubations) of S. mutans to pyrophosphate and sodium dodecyl sulfate caused pronounced inhibition of growth over the 24-h test period. Under the constraints of the conditions used, these studies indicate that pyrophosphate and sodium dodecyl sulfate can substantially inhibit the growth of oral bacteria. These compounds may affect the oral microflora of patients who routinely use tartar-control dentifrices and mouthrinses.

Evaluation of anti-calculus efficacy. An SEM method of evaluating the effectiveness of pyrophosphate dentifrice on calculus formation

A double-blind, cross-over study was carried out to assess the anti-calculus effectiveness of a pyrophosphate containing cleaning gel. 2 groups of 30 heavy calculus formers were followed up comparing conventional clinical scoring systems (Volpe-Manhold-Index and Marginal-Line-Calculus-Index) and micromorphologic SEM criteria of calculus formation and inhibition. The results indicated that after a 3-month period, there was a significant reduction of calculus formation compared to a placebo gel. The proposed SEM calculus index (SEMCI) objectively reflects the reduction of supragingival calculus formation.