Toothpastes

C. van Loveren

• Éditeur: S. Karger
• Année: 2013
• ISBN:
  9783318022070
• Sujet: Medicine
• Sous-sujet: Public Health, Administration & Care

With the mass-marketed introduction of fluoride in toothpaste in the 1950s, toothbrushing with paste became indispensable for good oral health. Both the industry and the dental profession had ashared interest in advocating the widespreadcorrect use of good qualitytoothpaste. This publication starts with a general introduction on the purpose, history and composition of toothpaste. The following chapters deal with the clinical evidence of its effectiveness in caries prevention, reducing and preventing plaque, gin-givitis, halitosis, and calculus formation, facilitating removal and prevention of extrinsic stain, and preventing dentine hypersensitivity and erosion. Later chapters provide valuable information on the abrasiveness of the pastes, the substantivity of active ingredients in the oral cavity and the possible models to study the effectiveness of the pastes when full-scale clinical trials are not possible. The final chapter focuses on the frequency of toothbrushing and post-brushing rinsing behavior. The book provides indispensable information for dentists, dental students and community dental programs on whether toothpastes can be recommended to patients for specific aims and how to use them to obtain the best effect.

van Loveren C (ed): Toothpastes. Monogr Oral Sci. Basel, Karger, 2013, vol 23, pp 27-44
DOI: 10.1159/000350465

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Antiplaque and Antigingivitis Toothpastes

Mariano Sanz · Jorge Serrano · Margarita Iniesta · Isabel Santa Cruz · David Herrera

Etiology and Therapy of Periodontal Diseases Research Group, Faculty of Odontology, University Complutense, Madrid, Spain

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Abstract

Dentifrices are a general term used to describe preparations that are used together with a toothbrush with the purpose to clean and/or polish the teeth. Active toothpastes were first formulated in the 1950s and included ingredients such as urea, enzymes, ammonium phosphate, sodium lauryl sarcosinate and stannous fluoride. Later, therapeutic agents were included. Today’s toothpastes have two objectives: to help the toothbrush in cleaning the tooth surface and to provide a therapeutic effect. The therapeutic effect may have an antiplaque or anti-inflammatory basis when the nature of the agents is antimicrobial. Plaque inhibitory and antiplaque activity of toothpastes used for chemical plaque control is evaluated in distinct consecutive stages, the last being home use randomized clinical trials of at least 6 months’ duration. In this chapter, the scientific evidence supporting the use of the most common antiplaque agents, included in toothpaste formulations, is reviewed, with a special emphasis on 6-month clinical trials, and systematic reviews with meta-analyses of the mentioned studies. Among the active agents, the following have been included in toothpastes: enzymes, amine alcohols, herbal or natural products, triclosan, bisbiguanides (chlorhexidine), quaternary ammonium compounds (cetylpyridinium chloride) and different metal salts (zinc salts, stannous fluoride, stannous fluoride with amine fluoride). Dentifrices are the ideal vehicles for any active ingredient used as an oral health preventive measure since they are used in combination with toothbrushing, which is the most frequently employed oral hygiene method. The most important indications of dentifrices with active ingredients are associated with long-term use to prevent bacterial biofilm formation, mostly in gingivitis patients or in patients on supportive periodontal therapy.

Copyright © 2013 S. Karger AG, Basel

Dentifrices are a general term used to describe preparations that are used together with a toothbrush with the purpose to clean and/or polish the teeth. Dentifrices can be prepared as powders, gels or toothpastes depending on the water content. Toothpastes usually, but not necessarily, have high water content, while powders have almost none. In gels, most of the water content is replaced by a humectant. In the present chapter, the terms dentifrice and toothpaste are used indistinctively.

Human beings were always conscious of the importance of using toothpaste as part of oral hygiene practices. In fact, the first known tooth cream was reported in Egypt, back in 3000-5000 BC. Archaeological research has also suggested that Greek and Roman civilizations used a powder from cru shed bones from different animals as a dentifrice. Around 500 BC, Chinese added flavorings to the powders, such as ginseng and other herbs. The modern era of therapeutically active toothpastes, however, did not start until the 1950s, when the first chemically active ingredients were added, such as urea, enzymes, ammonium phosphate, sodium lauryl sarcosinate and stannous fluoride.

Overall, modern toothpastes have both cosmetic and therapeutic objectives: to help the toothbrush in cleaning the tooth surface and provide a fresh breath (the cosmetic effect) and to provide a therapeutic effect, mainly through anti-caries, antihalitosis, antiplaque or anti-inflammatory effects.

Composition of Toothpastes

Toothpastes are formulated by combining multiple ingredients, and special attention must be paid to avoid the possible interactions that may occur among them. Among the ingredients that are usually part of a dentifrice formulation, the most important are listed in table 1 [see the chapter by Lippert for more details, see page 1-14]. In addition, different active agents, being antimicrobial in nature, have been included in toothpastes to provide a therapeutic effect aiming to help in controlling plaque and gingivitis. The adjunctive use of these toothpastes may increase the efficacy of tooth-brushing alone since the mechanical action of the toothbrush will reduce the amount of biofilm and disrupt its structure, thus facilitating the pharmacological mechanism of action of the toothpaste formulation [1]. Among the active agents, the following have been included in toothpastes: enzymes, amine alcohols, natural products, triclosan, bisbiguanides (chlorhexidine, CHX), quaternary ammonium compounds (cetylpyridinium chloride, CPC) and different metal salts (zinc salts, stannous fluoride, stannous fluoride with amine fluoride, AmF).

The present review will also consider gels, if they are used together with toothbrushing, as part of plaque control. Since gels do not include abrasives or detergents, they are easier to formulate, but their pharmacokinetics are less predictable. In addition, both dentifrices and gels lack the ability to access difficult to reach areas, such as the tonsils, the dorsum of the tongue, etc.

Mechanisms of Action and Classification of the Active Ingredients

Oral hygiene products used for chemical plaque control have been categorized according to their mechanism of action [2] as: (a) antimicrobial agents, when demonstrating a bacteriostatic or bactericidal effect in vitro; (b) plaque-reducing/inhibitory agents, when demonstrating an in vivo significant quantitative or qualitative effect on plaque levels, which may not have a significant effect on gingivitis and/or caries; (c) antiplaque agents, when demonstrating an in vivo significant effect on plaque levels sufficient to achieve a significant benefit in terms of gingivitis and/or caries control; (d) antigingivitis agents, when demonstrating an in vivo significant reduction in gingival inflammation without, necessarily, reducing dental plaque levels.

The previous definitions are widely accepted in Europe, but in North America the term antiplaque refers more often to agents capable of significantly reducing plaque levels and antigingivitis to agents capable of significantly reducing gingivitis levels.

Antiplaque activity may be achieved by different mechanisms of action: (a) by preventing bacterial adhesion; (b) by limiting bacterial growth and/or coaggregation; (c) by disrupting an already established biofilm; (d) by altering the composition and/or pathogenicity of the biofilm (see fig. 1). Its efficacy should be demonstrated in well-designed clinical trials through quantitative (re-duction of the number of microorganisms) and/ or qualitative (altering the vitality of the biofilm) effects [1].

Table 1. Toothpaste ingredients, adapted from Davies et al. [168]

Abrasives	Surfactants	Humectants
Alumina Aluminium trihydrate Bentonite Calcium carbonate Calcium pyrophosphate Dicalcium phosphate Kaolin Methacrylate Perlite (a natural volcanic glass) Polyethylene Pumice Silica Sodium bicarbonate Sodium metaphosphate	Amine fluorides Dioctyl sodium sulfosuccinate Sodium lauryl sulfate Sodium N lauryl sarcosinate Sodium stearyl lactate Sodium lauryl sulfoacetate	Glycerol PEG 8 (polyoxyethylene glycol esters) Pentatol PPG (polypropylene glycol ethers) Sorbitol Water Xylitol
Thickeners	Flavors	Preservatives
Carbopols Carboxymethyl cellulose Carrageenan Hydroxyethyl cellulose Plant extracts (alginate, guar gum, gum arabic) Silica thickeners Sodium alginate Sodium aluminum silicates Viscarine Xanthan gum	Aniseed Clove oil Eucalyptus Fennel Menthol Peppermint Spearmint Vanilla Wintergreen	Alcohols Benzoic acid Ethyl parabens Formaldehyde Methylparabens Phenolics (methyl, ethyl, propyl) Polyaminopropyl biguanide
Colors	Film agents	Sweeteners
Chlorophyll Titanium dioxide	Cyclomethicone Dimethicone Polydimethylsiloxane Siliglycol	Acesulfame Aspartame Saccharine Sorbitol

Evaluation of the Plaque Inhibitory and Antiplaque Activity of Toothpastes

In order to demonstrate the plaque inhibitory and antiplaque activity of toothpastes used for chemical plaque control, different consecutive stages of evaluation have been proposed, the last being the home use randomized clinical trial of at least 6-months’ duration [3].

In vitro Studies

Toothpaste formulations including active agents combine different ingredients that may inter...