🥳Perio 9

Locally Delivered, Controlled-Release Antimicrobials

Objectives

  • Periodontitis is a bacterial infection.

  • Focus of nonsurgical periodontal therapy including scaling and root planing (SRP) is to combat infection.

  • Current chemical antibacterial strategies include:

    • Systemic drug delivery

    • Oral rinses or toothpaste

    • Irrigating devices

  • These therapies have not significantly reduced signs of periodontitis.

  • New strategies involve controlled-release delivery systems:

    • Antimicrobials are deposited directly into the periodontal pocket.

    • Maintain effective drug concentrations over extended periods.

  • Can be used as monotherapy or adjunctively with SRP.

Types of Controlled-Release Antimicrobials

  1. Chlorhexidine-based Products:

    • Chlorhexidine chip

    • PerioCol-CG

    • Chlo-Site

  2. Doxycycline-based Products:

    • Ligosan slow release

    • Doxycycline gel (Atridox)

  3. Periodontal Plus AB

  4. Minocycline Microspheres (Arestin)

Chlorhexidine-Based Products

Chlorhexidine Chip

  • Description:

    • Small, orange-brown, rectangular chip for insertion into periodontal pockets.

    • Weighs approximately 6.9 mg; contains 2.5 mg of chlorhexidine gluconate in a biodegradable gelatin matrix.

    • Individually packed in aluminum blister packs.

    • Storage: 20° - 25°C (excursions to 15° - 30°C permitted).

Dosage and Administration

  • Insert one chip into pockets with probing pocket depth (PPD) ≥ 5mm, once every three months.

  • Isolate and dry the pocket area prior to insertion.

  • Insert chip to maximum depth; chip biodegrades completely.

Dislodgement Protocols

  • After 7 Days: Consider full treatment received.

  • Within 48 Hours: Insert a new chip.

  • After 48 Hours: Reassess at 3 months. Insert new chip only if PPD remains ≥ 5mm.

Mechanism of Action

  • Releases chlorhexidine biphasically: 40% within 24 hours, remainder over 7-10 days.

  • Active against a broad range of microbes; disrupts cell membrane, precipitating cell death.

  • No adverse effects noted on oral microbial flora.

Indications and Usage

  • Adjunct to SRP for reducing pocket depth in periodontitis patients.

  • Part of a periodontal maintenance program.

Contraindications

  • Do not use in patients with known chlorhexidine sensitivity.

Patient Guidance

  • Avoid brushing at the site for 3 days; avoid flossing for 10 days post-placement.

  • Cautious eating from the treated side; notify dentist if chip dislodges.

  • Mild sensitivity post-placement is normal; report severe reactions.

Other Chlorhexidine Products

PerioCol-CG

  • Small 10-mg chip made of collagen matrix with 2.5 mg chlorhexidine.

  • Resorbs in 30 days; coronal edge degrades within 10 days.

  • Releases approximately 40-45% chlorhexidine within the first 24 hours.

Chlo-Site

  • Xanthan gel containing 1.5% chlorhexidine; injected into the periodontal pocket.

  • Consists of two chlorhexidine types: slow-release (0.5%) and rapid-release (1.0%).

  • Retained within the pocket, disappearing in 10-30 days.

Doxycycline-Based Products

Ligosan Slow Release

  • Resorbable doxycycline gel in a laminate pouch refrigerated.

  • Contains various single-application cartridges; concentrate remains above 16 µg/mL for 12 days.

Doxycycline Gel (Atridox)

  • Two-syringe system: one syringes contains bioabsorbable polymer, the other doxycycline.

  • Releases drug upon contact with crevicular fluid for 7 days.

Mechanism of Action

  • Bacteriostatic; inhibits protein synthesis via disruption of tRNA and mRNA.

  • Observed no overgrowth of opportunistic organisms post-use.

Indications and Usage

  • Treatment of periodontitis for clinical attachment gain and reduced bleeding/probing depth.

  • Gel biodegradable; no removal required.

Periodontal Plus AB

  • Bio-resorbable tetracycline fiber (25 mg collagen + 2 mg tetracycline).

  • Biodegrades in 7 days; retain with dressing for 10 days.

Minocycline Microspheres (Arestin)

  • Controlled-release product delivering 1 mg of minocycline.

  • Mechanism: Inhibits protein biosynthesis, broad-spectrum activity.

  • Usage: Adjunct to SRP for reduced pocket depth.

Rationale for Local Delivery and Controlled Release

  • Periodontal disease as a bacterial infection; mechanical therapies alone insufficient.

  • Various delivery strategies (systemic, local) have shown limited effectiveness compared to controlled-release formulations.

  • Dynamics of GCF can wash out antimicrobials unless delivered in controlled release formats.

  • Results in sustained effective concentrations overcoming bacterial biofilms.

  • Decreased systemic effects and lower risk of microbial resistance are additional benefits.

Clinical Significance

  • Enhanced clinical efficacy of SRP with adjunctive therapy.

  • Significant pocket depth reduction when used alongside SRP.

Clinical Indications

  1. Adjunctive Therapy: Improve SRP outcomes.

  2. Surgical Therapy: Enhance results post-surgery in persistent pockets.

  3. Peri-implantitis Treatment: Target local microflora at implant sites.

  4. Tobacco Smoking Consideration: Improve efficacy in smokers.

Adverse Effects

  • Possible hypersensitivity and overgrowth of non-susceptible microorganisms.

  • Headaches, infections, pain, swelling/inflammation.