Chapter 28: Dentifrices and Mouthrinses

Chapter 28: Dentrifices and Mouthrinses (Dentifrices and Mouthrinses)

  • Source: Wilkins, Clinical Practice of the Dental Hygienist, 14th Edition (2024)
  • Topics covered: active vs inactive ingredients, mechanisms of action for preventive/therapeutic agents, purposes and use, regulatory seals (ADA/CDA), and practical considerations for patients.

What is a Dentrifice?

  • A paste or substance used with a toothbrush for cleaning accessible surfaces of teeth.
  • Types:
    • Therapeutic dentifrices: help reduce disease processes (caries, gingivitis, calculus, hypersensitivity).
    • Cosmetic dentifrices: cleans and polishes teeth (stains).

Active vs Inactive Ingredients

  • Active Ingredients: component of a drug/substance that has biological activity.
  • Inactive Ingredients (excipients): do not have direct biological activity but influence shelf-life, stability, flow, pH, etc.
  • Note: Both types are present in dentifrices to achieve efficacy, stability, palatability, and convenience.

Basic Components of Dentifrices: Inactives

  • Detergents (foaming agents/surfactants)
  • Cleaning and polishing agents (abrasives)
  • Binders (thickeners)
  • Humectants (moisture stabilizers)
  • Preservatives
  • Flavoring agents (sweeteners)
  • See Table 28-1 and Table 28-2 for specifics and therapeutic ingredients.

Table 28-1: Ingredients and Functions of Commercially Available Dentifrices

  • Surfactant/detergent: Function — Foaming and cleansing; Average formulation: 1-2%.
  • Abrasive: Function — Cleaning and polishing; Average formulation: 20-40%.
  • Binder: Function — Thickening agent and stabilizes formula; Average formulation: 1-2%.
  • Humectant: Function — Prevents water loss / hardening of dentifrice; Average formulation: 20-40%.
  • Preservative: Function — Prevents microorganisms from destroying the dentifrice in storage; Average formulation: 2-3%.
  • Flavoring: Function — Provides flavor (percentage not clearly specified in transcript).
  • Water: Function — Vehicle for formulation; percentage not clearly specified in transcript.
  • Sweetener: Function — Maintains ingredient in formulation; Average formulation: 1-1.5%.

Table 28-2: Therapeutic Active Ingredients in Dentifrices

  • Antibiofilm/antigingivitis: Active ingredients include stannous fluoride and zinc citrate.
  • Anticalculus: Active ingredients include tetrapotassium pyrophosphate, tetra-sodium pyrophosphate, sodium hexametaphosphate, and various zinc compounds.
  • Desensitizer: Active ingredients include potassium nitrate, potassium citrate, potassium chloride, stannous fluoride, and strontium chloride.
  • Oral malodor: Active ingredients include essential oils, chlorine dioxide, and stannous fluoride/sodium hexametaphosphate.

Desensitizing Dentrifices

  • Examples (desensitizing/anti-sensitivity toothpastes): Colgate Sensitive, ARM & HAMMER, Sensodyne (Original Flavor), and others mentioned in notes.
  • Active ingredients typically include:
    • Potassium nitrate and/or stannous fluoride (often with fluoride ion present)
  • Inactive ingredients commonly listed:
    • Water, sorbitol, glycerin, hydrated silica, cellulose gum, sodium methyl cocoyl taurate, silica, titanium dioxide, flavor, sodium saccharin, trisodium phosphate, red 28.
  • Mechanism: Desensitizing toothpastes relieve sensitivity by blocking pain signals from the tooth surface to the sensory nerves inside the tooth.
    • Key concept: Ingredients enter dentin tubules and interfere with nerve transmission to reduce pain sensation.

How Do Desensitizing Toothpastes Work?

  • Desensitization concept: blocks pain signals between the tooth’s surface and sensory nerves inside the tooth.
  • Common active desensitizing ingredients and their roles:
    • Potassium nitrate, stannous fluoride, strontium compounds, etc., which help reduce stimulus transmission to nerves.
  • Result: Reduced tooth sensitivity during brushing and normal activities.

Pain Relief Toothpaste: Summary and Mechanisms

  • Pain relief toothpastes address sensitivity and pain with ingredients like:
    • Potassium nitrate (KNO₃): interferes at the nerve synapses to prevent pain signal transmission.
    • Stannous fluoride (SnF₂): can help plug dentin tubules, reducing stimulus transmission.
    • Sodium fluoride: provides caries protection while contributing to desensitization.
  • Mnemonic notes on SNF2 and KNO₃ are used in the text to highlight the mechanisms:
    • SNF2: blocks tubule pathways to nerves; improves tolerance to beverages/foods.
    • KNO₃: numbs nerves by affecting synaptic transmission.

Malodor Dentrifices

  • Product example: Hello brand toothpaste marketed as vegan with hemp seed oil + coconut oil for freshening.
  • Claims include: natural freshening, anti-bad-breath properties.
  • Typical ingredients in such formulations (as listed):
    • Sorbitol, hydrated silica (polish/clean), purified water, vegetable glycerin, xylitol, erythritol (natural sweeteners), flavor (xanthan gum), titanium dioxide, hemp seed oil, coconut oil, stevia (sweetener), tea tree oil, etc.
  • Note: Marketing terms and ingredient lists reflect cosmetic claims and natural/organic positioning rather than conventional therapeutic claims.

Whitening Dentrifices

  • Whitening toothpastes contain abrasive components and bleaching agents such as:
    • Silica, pyrophosphates, hydrogen peroxide (HP), or carbamide peroxide (CP).
  • Some whitening toothpastes include ingredients that help relieve tooth sensitivity (potassium nitrate, stannous fluoride).
  • Desensitizing mechanisms among whitening formulations are included to maintain tooth comfort while whitening.

Teeth Whitening Ingredients: Hydrogen Peroxide (HP) vs Carbamide Peroxide (CP)

  • HP (Hydrogen Peroxide):
    • What it is: Strong bleaching agent.
    • How it works: Breaks down into oxygen that penetrates enamel and whitens stains from within.
    • Speed: Fast; often used in in-office procedures.
    • Strength: Higher strength yields faster results but increases risk of sensitivity and gum irritation if overused.
    • Analogy: Think of it as a strong cleaner—quick results, but must be used carefully.
    • Representation using LaTeX: chemical reaction can be represented as
    • ext{HP}
      ightarrow ext{O}2 + ext{H}2 ext{O} ext{ (in enamel tissue)}
  • CP (Carbamide Peroxide):
    • What it is: Gentler version of HP.
    • How it works: Decomposes to hydrogen peroxide and urea; then acts similarly to HP but more slowly.
    • Speed: Slower, suitable for at-home use (gel/strips).
    • Strength: Gentler, good for sensitive teeth.
    • Example: Opalescence Whitening Toothpaste contains CP and fluoride for cavity protection.
    • Analogy: Slow-release version of HP—milder, longer-lasting results.
  • PAP (Phthalimidoperoxycaproic Acid):
    • What it is: A newer, non-peroxide whitening agent.
    • How it works: Oxidizes stains without releasing free radicals, whitening without enamel damage or sensitivity.
    • Speed: Similar to CP.
    • Strength: Effective yet gentler, suitable for very sensitive teeth.
    • Example: Hismile PAP+ Whitening Toothpaste uses PAP+ for peroxide-free whitening.

Active Components of Dentifrices

  • Goals: Prevention or reduction of oral disease; considerations for pediatric patients; patient-specific dentifrice recommendations.

Dentrifices Safe for Children

  • A comprehensive safety checklist for pediatric formulations:
    • Fluoride-free versions available for certain populations.
    • Dye-free, microbead-free, TEA-free, SLS-free, PEG-free, animal fat-free, paraben-free, formaldehyde-free, formaldehyde donor-free, artificial sweeteners-free, butylparaben-free, mineral oil-free, triclosan-free, phthalate-free, gluten-free, artificial color-free, diethanolamine-free, artificial flavors-free.
  • Purpose: Minimize exposure to potentially harmful additives while providing safe fluoride or nonfluoride options.

Pediatric Considerations for Dentrifices

  • Key guidelines for fluoride use:
    • The CDC recommends children begin using fluoride toothpaste at age 2, with a rice grain-sized amount for children under 3 and a pea-sized amount for children 3–6.
    • Fluoride toothpaste should be used twice daily.
    • ADA Seal of Acceptance is a recommended criterion for brands.
    • International fluoride recommendations: ~1000 ppm fluoride for children under 6 and up to ~1500 ppm for older children.
  • Purpose of fluoride in children: strengthen enamel, reduce caries risk, and assist in enamel remineralization.

Dentrifices with Fluoride for Children

  • Fluoride benefits for children:
    • Strengthens enamel and makes teeth more resistant to bacteria.
    • Inhibits bacteria formation layers that lead to decay.
    • Aids in enamel repair of damaged areas on the outer shield.

Mouthrinses: Overview and Uses

  • Purposes and uses (1 of 2):
    • Before professional treatment: reduce intraoral microorganisms in aerosols; limit aerosol contamination during use of handpiece or ultrasonic scalers.
  • Purposes and uses (2 of 2):
    • Self-care for personal oral needs; biofilm control; caries prevention through remineralization of early non-cavitated lesions; gingivitis prevention; malodor control; posttreatment therapy after non-surgical periodontal therapy.
  • Note: Some mouthrinses are designed for adjunctive use with scaling/root planing and other procedures.

Alcohol in Mouthwash: Key Points

  • Most mouthrinses contain ethanol (alcohol), which can cause burning sensation and dry mouth.
  • Ethanol kills both beneficial and harmful bacteria; not ideal for xerostomia.
  • Alcohol-free mouthrinses are better for sensitive mouths and those with dry mouth conditions.
  • For individuals recovering from alcohol abuse, avoid alcohol-based rinses.
  • Examples: Listerine contains approximately 26.9\% ethanol; typical beer is around 4.2\%.

Alcohol-Free Mouthrinses

  • Examples include various brands marketed as zero- or low-alcohol options:
    • Crest All Day Fresh Mint, Scope Zero, Crest Total Care Zero Alcohol, Listerine Total Care Zero, ACT Zero, etc. (brand list provided in transcript in slide format).

Mouthrinses for Children

  • Most dentists recommend children begin using mouthwash around age six, when teeth are more developed and they can reliably rinse and spit.

Whitening Mouthrinses

  • Whitening mouthrinses use low concentrations of hydrogen peroxide or alternative chelating/cleansing agents.
  • Typical active ingredients include low-level HP and polyphosphate systems (e.g., sodium hexametaphosphate, potassium pyrophosphate) and sodium citrate.
  • These rinses whiten teeth by either mild bleaching or by aiding stain removal/control.

Functions of Chemotherapeutic Agents (Box 28-1)

  • Remineralization: Restore mineral elements.
  • Antimicrobial: Bactericidal or bacteriostatic; biofilm control.
  • Gingival health: Reduction/prevention of gingivitis.
  • Astringent: Shrink tissues.
  • Anodyne: Alleviate pain.
  • Buffering: Reduce oral acidity.
  • Deodorizing: Neutralize odor.
  • Oxygenating: Cleanse.

Preventive/Therapeutic Agents of Mouthrinses

  • Examples of agents:
    • Fluoride
    • Chlorhexidine (CHX) – see Figures 28-1 and 28-2
    • Phenolic-related essential oils
    • Quaternary ammonium compounds
    • Oxygenating/oxidizing agents

Peridex™ (Chlorhexidine Gluconate 0.12%)

  • CHX is an antiseptic/disinfectant that reduces bacteria in the mouth.
  • Oral health benefits: helps with gingivitis, bleeding, ulcers, and infections.
  • Benefits vs. side effects: daily use can aid outcomes but may cause tooth staining, altered taste, and mouth irritation; prolonged use may disrupt the oral microbiome balance.

Therapeutic Mouthrinse: Chlorhexidine (CHX)

  • CHX rinse beneficial for gingivitis/periodontal therapy but limited by side effects and long-term use considerations.

Commercial Mouthrinse Ingredients (Table 28-3 overview)

  • Active ingredients: See Box 28-2 for representative chemotherapeutic agents.
  • Inactive ingredients include: water, alcohol, flavoring, humectants, preservatives, dyes, sweeteners, and active/functional ingredients.
  • Major vehicle to carry other ingredients: water (the aqueous base).
  • Preservatives help maintain shelf-life; flavoring components improve palatability; dyes provide color; sweeteners provide taste.

Typical Commercial Mouthrinse Formulations (Table 28-3 concept overview)

  • Key components: Water, Alcohol, Flavoring, Humectant, Preservative, Dyes, Sweeteners, Active ingredients.
  • Function of each category explained in context of mouthrinse performance and user experience.

Characteristics of an Effective Chemotherapeutic Agent (Box 28-2)

  • Nontoxic: The agent does not damage oral tissues or cause systemic harm.
  • No or limited absorption: Action is localized to the oral cavity.
  • Substantivity: Ability to bind to pellicle/tooth surface and release over time while retaining potency.
  • Bacterial specificity: Targeted or broad-spectrum, with affinity for oral pathogens.
  • Low-induced drug resistance: Low propensity to drive resistance.

Procedure for Rinsing

  • General cues and guidance on proper rinsing technique and timing (content presented as an instructional image in slide).

Emerging Alternative Practices

  • Oil pulling: Swishing 10 mL (one tablespoon) of sesame or coconut oil for antimicrobial and biofilm effects.
  • Reported benefits: reduction of biofilm, reduction of bacteria linked to caries, gingivitis, halitosis, and oral thrush.
  • Note: Not a substitute for mechanical biofilm control; should be used as adjunct.

ADA Seal and CDA Seal of Acceptance

  • The ADA (American Dental Association) Seal and the Canadian Dental Association Seal indicate product safety and efficacy claims have met professional standards.
  • Seals are re-evaluated periodically; use as a guide for choosing products.

Documentation in Clinical Practice (Box 28-4)

  • Documentation should include:
    • Recommended dentifrice and mouthrinse for daily self-care (favor nonalcohol-containing mouthrinses and antibacterial dentifrices).
    • Patient instruction details: how to use, amounts, and frequency.
    • Summary of current oral findings indicating need for recommendations.
  • Example documentation (Box 28-4): Choosing a Mouthrinse for a Patient with Xerostomia
    • Case: 76-year-old male with dry mouth; history of smoking; long-term use of a mouthwash; intraoral findings show decreased salivary flow; generalized 3- to 4-mm pockets; discuss xerostomia causes and effects of alcohol on the oral cavity; recommend alcohol-free mouthwash; documentation signed by RDH.

Factors to Teach the Patient

  • The significance of ADA or CDA Seal of Acceptance as a guide for safety/efficacy.
  • Encourage patients to discuss new products with their oral health professional to ensure appropriateness for their condition.
  • Avoid impulse purchases that may conflict with their oral condition or restorations.
  • Emphasize that chemotherapeutics are not substitutes for daily biofilm removal.
  • Check ingredients to prevent purchasing high-alcohol products if contraindicated (xerostomia, alcohol-use history).
  • Ensure understanding of how adherence to recommended chemical agents relates to outcome expectations.

Key Takeaways for Exam Preparation

  • Dentifrices contain both active (therapeutic) and inactive ingredients that affect efficacy, stability, and user experience.
  • Therapeutic dentifrices address caries, gingivitis, calculus, hypersensitivity, and malodor; cosmetic dentifrices focus on cleaning and whitening.
  • Desensitizing dentifrices use osmotic or tubule-occluding strategies (e.g., potassium nitrate, stannous fluoride) to reduce dentin hypersensitivity.
  • Whitening dentifrices combine abrasives with bleaching agents (HP or CP) and may include desensitizing ingredients; PAP offers peroxide-free options.
  • Mouthrinses provide antimicrobial, anti-gingivitis, remineralization, and malodor control benefits; CHX is effective but has staining and taste alteration risks with long-term use.
  • Alcohol content in mouthrinses has important implications for xerostomia, sensitivity, and recovery from alcohol use; alcohol-free options exist.
  • Pediatric considerations include fluoride dosing per age, ADA Seal usage, and safety requirements for children’s dentifrices.
  • Documentation in the patient record should reflect product recommendations, usage instructions, and rationale based on findings.
  • Emerging practices (e.g., oil pulling) are adjuncts and should not replace mechanical biofilm removal.

Formulas and numerical references (for quick recall):

  • Fluoride toothpaste fluoride levels:
    • Under 6 years: typically around the lower end of recommended ppm ranges, with guidance from CDC/ADA; international recommendations often around 1000\ \text{ppm} for younger children and up to 1500\ \text{ppm} for older children.
  • Alcohol content in some mouthrinses: 26.9\% by volume for Listerine; typical beer ~4.2\%.
  • Hydrogen peroxide whitening strength and speed vary by concentration; stronger HP yields faster whitening but increased sensitivity risk.
  • Caries remineralization/reduced biofilm effects are tied to agents like fluoride, zinc citrate, stannous fluoride, etc.

If you’d like, I can tailor these notes to a specific exam outline or condense them into a narrower study guide focusing on the most test-relevant points.