Antimicrobial Agents for Periodontal Disease

ANTIMICROBIAL AGENTS FOR THE CONTROL OF PERIODONTAL DISEASE

LEARNING OBJECTIVES

• Discuss oral disease in relation to bacterial plaque biofilm.
• Outline the mechanisms for ensuring efficacy, quality, and safety of periodontal antimicrobial products.
• Explain the rationale for adjunctive antimicrobial biofilm control.
• Compare and contrast delivery methods of antimicrobial agents for both home and professional use.
• Discuss evidence regarding the effectiveness of various active ingredients included in antimicrobial products for the treatment of periodontal disease.
• Apply evidence-based indications for the use of antimicrobial agents as interventions for the prevention and treatment of periodontal disease.
• Discuss legal, ethical, and safety issues related to antimicrobials.

ORAL DISEASE AND BACTERIAL PLAQUE BIOFILM

• Prevention and control of periodontal disease depend in part on controlling bacterial oral plaque.
• Dental hygienists play a key role by advising their patients about performing adequate homecare and providing necessary preventive and therapeutic professional care.
• Indications for antimicrobial use will often emerge during the assessment phase of the dental hygiene process of care.

PRODUCT SAFETY AND EFFICACY

• American Dental Association (ADA) Council on Scientific Affairs and Canadian Dental Association (CDA) provide additional guidance to oral healthcare providers.
• Two major organizations in the United States and Canada contribute to ensuring the safety, quality, and efficacy of oral antimicrobials:
  • U.S. Food and Drug Administration (FDA)
  • Health Canada

RATIONALE FOR ADJUNCTIVE ANTIMICROBIAL BIOFILM CONTROL

• Periodontal health requires a combination of supportive periodontal therapy and daily oral hygiene efforts.
• Oral antimicrobial agents have a definitive adjunctive benefit for reducing plaque biofilm and gingival inflammation beyond what is accomplished mechanically.

DELIVERY SYSTEMS AND ACTIVE INGREDIENTS

• Dental hygienists can view oral antimicrobial agents as having two dimensions:
  • Delivery system
  • Active ingredient
• Delivery systems can be subcategorized:
  • Local delivery methods
  • Systemic delivery methods

ACTIVE INGREDIENT MECHANISMS OF ACTION

• Antiseptic agents: kill or prevent propagation of plaque microorganisms.
• Antibiotics: inhibit or kill specific bacteria or groups of bacteria, or modulate the host inflammatory response.
• Modifying agents: agents that alter the structure and/or metabolic activity of bacteria.
• Antiadhesives: interfere with the ability of bacteria to attach to acquired pellicle.

SELF-APPLIED MODES OF DELIVERY

• Dentifrices: available mostly as paste or gel.
• Mouth rinses: available for both cosmetic and therapeutic use.
• Antiseptics: substances that inhibit the growth and development of microorganisms.
  • Demonstrate very little oral or systemic toxicity or microbial resistance.
• Chlorhexidine gluconate (CHX): long viewed as the gold standard of therapeutic mouth rinses.
  • Available only by prescription.
• Essential oils: components of plants that contain phenolic compounds that destroy microorganisms by compromising the cell membrane and inhibiting enzyme activity.
• Cetylpyridium chloride (CPC): mouth rinses that have antimicrobial properties.
• Probiotics: live microorganisms that have health benefits for the host when administered alone or in combination.
• Oral irrigation: both powered and manual mechanisms for delivering an active ingredient within a solution via an irrigation tip into the gingival sulcus or periodontal pocket.

OTHER MOUTH RINSE INGREDIENTS UNDERGOING STUDY

• Chitosan
• Teas
• Salvadora persica
• Taurolidine
• Pomegranate
• Edible oils
• Aloe vera
• Propolis (bee products)
• Sodium hypochlorite (bleach)
• Tumeric
• Neem tree products
• Cinnamon
• Algae
• Witch hazel
• Other polyherbals

PROFESSIONALLY APPLIED MODES OF DELIVERY

• Professionally applied antimicrobial agents are aimed at reducing pathogenic bacteria in diseased sites that have resisted healing.
• Can be applied locally or systemically.
• Controlled-release drug delivery: the use of professionally placed intracrevicular devices that provide drug delivery for sustained periods of time.
• Minimum inhibitory concentration (MIC): research measurement tool used for products to describe the lowest concentration of a particular antimicrobial.
• With advanced periodontal disease, periodontal treatment planning often involves a hygienist.
• Minocycline microspheres: includes minocycline hydrochloride; available in North America as a dry powder; delivered via syringe-like handle to the base of the periodontal pocket; immediately adheres.
• Chlorhexidine chip (PerioChip): biodegradable 4- to 5-mm hydrolyzed gelatin chip that incorporates 2.5 mg of chlorhexidine d-gluconate for insertion into pockets.
  • Moderate level of certainty surrounding an overall moderate benefit resulting from the chip.
  • ADA recommends as an adjunctive periodontal antimicrobial.
• Doxycycline hyclate gel (ATRIDOX): consists of 10% doxycycline hyclate in a gel polymer.

CLIENT EDUCATION AND MOTIVATION REGARDING CONTROLLED RELEASE ANTIMICROBIAL INTERVENTIONS

• Dental hygienist must discuss with the client both potential benefits and possible adverse effects of the antimicrobial agent.
• Dental hygienist must explain to the client that measurement and evaluation of clinical parameters will be required as a follow-up after the introduction of an antimicrobial intervention.

LASERS AS ADJUNCTS IN ANTIMICROBIAL PERIODONTAL THERAPY

• Dental lasers are classified according to:
  • Wavelength
  • Delivery system
  • Emission modes
  • Tissue absorption
  • Clinical applications

SYSTEMIC DELIVERY METHODS

• Ingested and then delivered via bloodstream.
• Antibiotics: type of systemically delivered antimicrobial drug used against bacterial infections in particular.
• Subantimicrobial systemic dose: administration of a reduced dose of a drug for purposes other than the elimination of a pathogenic organism (host modulatory therapy).

CONDITIONS ASSOCIATED WITH SYSTEMIC ANTIBIOTIC THERAPY

• Gastrointestinal upset
• Sensitivity to sunlight
• Intrinsic staining in developing teeth
• Potential toxicity to pregnant mother and fetus
• Increase in vaginal candidiasis
• Impaired absorption of some nutrients
• Depressed prothrombin activity
• Potential to render oral contraceptives less effective

LEGAL, ETHICAL, AND SAFETY ISSUES

• Most jurisdictions require a prescription by a dentist; may or may not be administered by a dental hygienist.
• Dental hygienist must adhere to regulations of their practice jurisdiction.
• Dental hygienists must be prepared to discuss interventions with patients based on the most current evidence.
• Responsibility of the entire oral healthcare team to provide evidence-based information to the patient.