Control of Microorganisms by Antibiotics

1. Control of Microorganisms by Antibiotics Weinberg, chapter 11

2. Properties of an Ideal Antibiotic • Bacterial specificity • Should not produce resistant strains • Does not cause allergy or toxicity • Does not cause other side effects • Does not eliminate normal oral flora • Cost effective • Hence the ideal has not been found!

3. Antibiotic Adjunctive Therapies • Treatment of aggressive periodontal diseases, chronic periodontitis, refractory periodontitis • Initial identification of pathogens • Appropriate antibiotic selection • Debridement should be carried out first • Systemic antibiotics commonly prescribed: • tetracyclines, metronidazole • amoxicillin, Augmentin, ampicillin • ciprofloxacin, clindamycin • Periostat (doxycycline)

4. Common side effects: Nausea, GI upset Diarrhea Rash Resistant bacteria Poor client compliance May be to broad spectrum Common oral manifestations: Black hairy tongue Oral candidiasis Systemic Use – Concerns

5. Controlled Release Agents • Work by suppressing destructive enzymes produced during inflammatory process or suppressing microbes • Considered for localized periodontal sites • Systems available include: • Actisite (tetracycline fiber) • Atridox (doxycycline gel) • Arestin (minocycline microsphere)

6. Advantages of Controlled Release Agents • Client compliance not an issue • GCF concentration greater than serum levels • Delivery is localized – reduces systemic effects • Reduced side effects

7. Tetracycline • Clinical Use: • Refractory periodontitis • Localized aggressive periodontitis • Growing trend to use combination therapies – more effective • Systemic & local delivery systems

8. Tetracycline • Mechanism of action: • Bacteriostatic, broad spectrum • More effective against gram-positive bacteria • However, A.a. highly susceptible • Non-antibacterial properties: • Inhibits production & secretion of collagenase • Inhibits bone resorption

9. Tetracycline • Mechanism of action: • Antibacterial properties: • Inhibits growth & multiplication of bacteria • Dosage: • 250 mg for 2 weeks

10. Intrinsic tooth staining GI upset, abdominal pain Diarrhea, vomiting Fungal overgrowth Resistant bacterial strains Interferes with bactericidal activity of penicillin's & cephalosporins Reduces effect of BCP Tetracycline – Side Effects

11. Actisite Periodontal Fiber • Clinical use: • Pockets measuring  5 mm, bleed on probing • Localized treatment for sites that have not responded to previous mechanical therapy • How supplied: • Cartons of 4 or 10 fibers • 23 cm in length • 12.7 mg tetracycline hydrochloride • Stored at room temperature

12. Actisite • Application: • Treat one quadrant or one side of mouth at a time • Client may request anaesthesia • Fiber inserted into pocket (circumferential or not) • Takes about 10 minutes/tooth • Some control of saliva • Should contact pocket base

13. Actisite • Application: • Sealed in place with adhesive • Apply in thin even line along gingival margin • Surgical dressing not necessary but has been used • Removed 7-10 days after placement • Curette and/or cotton pliers • Fiber comes out in mass or pieces • Debride areas as necessary • Tissue may appear red following removal

14. Actisite • Adverse effects: • Discomfort • Local erythema • Little systemic reaction • Used with caution in client with history of candidiasis • Application around 12+ teeth may result in oral candidiasis

15. Actisite • Client instructions: • Avoid brushing & flossing • Use antimicrobial rinse • Use of CHX may have syngerstic effect • Avoid hard or crunch foods, stick foods, chewing gum

16. Actisite • Clinical Efficacy: • Reduction in bleeding on probing and pocket depth • More significant reductions in deeper pockets • Reduction in periodontal pathogens • Effects of fiber on bone loss, tooth mobility or tooth loss not established

17. Metronidazole • Clinical use: • Refractory periodontitis (when combined with amoxicillin or Augmentin) • Necrotizing ulcerative gingivitis • Moderate – severe periodontitis • Aggressive periodontitis (LAP) when combined with amoxicillin or Augmentin • Following perio surgery if barrier membranes in place – suppresses P.g.

18. Metronidazole • Mechanism of action: • Bactericidal antimicrobial • Disrupts DNA synthesis leading to cell death • Selectively kills bacterial associated with periodontal disease • Susceptible bacteria include: • Fusobacterium, Bacteroides • Peptostreptococcus • Treponema, Campylobacter • Veillonella

19. GI disturbances Headache Dry mouth Candida infections Metallic taste Nausea, diarrhea Stomatitis Avoid alcohol when taking: acute nausea, headache, vomiting May decrease effects of BCP Metronidazole – Side Effects

20. Metronidazole • Clinical Considerations: • GCF concentrations > blood serum levels • When combined with oral hygiene & debridement = beneficial effect on periodontitis • Periodontal surgery may not be necessary • Doxycycline may be substituted for metronidazole • If client can’t abstain from alcohol

21. Probing depth of 6 mm Tissue shrinkage & recession Before & AfterTreatment with Metronidazole

22. 6 mm probing depths Surgery has not been required Before & After Treatment with Metronidazole

23. Metronidazole • Some evidence of bone gain – client 2.5 years after initial debridement and use of metronidazole

24. Metronidazole • Dosage: • 250 mg tid for 7-10 days • 500 mg bid for 1-2 weeks • Doxycycline • 100 mg per day or BID • Metronidazole and amoxicillin or Augmentin • 250 mg (of each) TID for 7-10 days

25. Arestin • Clinical use: • Periodontitis with pockets  5 mm • How supplied: • Box containing 2 trays each containing 12 cartridges • Cartridge contains 1 mg of minocycline (semisynthetic tetracycline derivative) microencapsulated in Poly dry powder • Cartridge inserted into a cartridge handle

26. Arestin  • Preparing for Arestin Premeasured, premixed, no refrigeration necessary

27. Arestin  • Mechanism of action: • Broad spectrum • Bacteriostatic • GCF levels maintained at high levels for at least 14 days

28. Arestin  • Application: • Insert tip to base of periodontal pocket • Expel powder into pocket • Bioadhesive microspheres activate & adhere on contact with moisture • Cartridge contains enough Arestin for one periodontal pocket • Clinical trials: 30 sites treated in less than 10 minutes • Dressings or adhesives not required

29. Arestin  • Adverse effects: • Headache • Pain • Mouth ulceration • Slu syndrome • Stomatitis

30. Arestin  • Client instructions: • Do not eat hard or sticky foods for 1 week • Postpone brushing for 12 hours • Do not use interproximal cleaning aids for 10 days

31. Arestin  • Clinical efficacy: • 27,000 sites treated, n=748

32. Arestin  • Clinical efficacy: • Arestin with debridement demonstrated 27% greater pocket reduction in molars compared to debridement alone • Mean reduction of 2 mm (pockets 7 mm +) • Effective in furcations