Chlorhexidine

presentation on chlorhexidine as a chemical plaque control agent

1. CHLORHEXIDINE DEPARTMENT OF PERIODONTOLOGY - JANANI.A

2. INTRODUCTION Dental plaque is defines as a highly specific variable structural entity formed by sequential colonization of microorganism on the tooth surface, epithelium and restorations Plaque control is the removal of microbial plaque and the prevention of its accumulation on the teeth and adjacent gingival tissues. It also deals with the prevention of calculus formation

3. CHLORHEXIDINE - INTRODUCTION Second generation chemical plaque control agent Highly bacteriostatic in nature Also used as antiseptic in various specialities Available in different forms for use

4. HISTORY Developed in 1940s by Imperial Chemical Industries, England Marketed in 1954 as antiseptic for skin wounds Later, widely used in medicine and surgery including obstetrics, gynaecology, urology and pre-surgical skin preparation In dentistry, initially as pre-surgical disinfectant of mouth and in Endodontics

5. 1969 - Schroeder investigated Plaque inhibition by CHX 1970 - Loe and Schiott did a definitive study on it Rinsing for 60 sec BD with 10ml of a 0.2% CHX solution without normal tooth cleaning inhibits plaque regrowth and development of gingivitis

6. CHEMISTRY BISBIGUANIDE antiseptic Symmetrical molecule 4 CHLOROPHENYL rings and 2 BIGUANIDE groups Connected by a Central HEXAMETHYLENE bridge 2 POSITIVE CHARGES on either side of the hexamethylene bridge Strong BASE DICATIONIC at pH levels >3.5 Extremely INTERACTIVE with anions due to its dicationic nature

7. Forms of chlorhexidine WATER SOLUBLE Digluconate Acetate SPARINGLY SOLUBLE Hydrochloride

8. MECHANISM OF ACTION

9. MECHANISM OF ACTION ON THE TOOTH SURFACE : CHX gets attached to the salivary proteins and desquamated epithelial cells Blocks acidic groups on salivary glycoproteins Reduces glycoprotein adsorption on tooth surface Prevents pellicle formation

10. Prolonged antiseptic release Bacteriostatic action that lasts for more than 12 hours Prevents the adsorption of bacterial cell wall on to the tooth surface Prevents plaque formation

11. Competes with calcium ions Blocks agglutination of plaque Prevents binding of mature plaque

12. ON THE BACTERIAL CELL MEMBRANE : AT LOW CONCENTRATIONS: CHX adheres to bacterial cell membrane Binds to phospholipids in the inner cell membrane Leakage of lesser molecular weight components Sub lethal stage – reversible bacteriostatic action

13. AT HIGH CONCENTRATIONS: The action continues Intracellular coagulation Leakage of intracellular components slow down Cytoplasmic coagulation Cell death (Bactericidal action)

14. Anionic substances like Sodium lauryl sulfate based toothpastes reduce plaque inhibition effect of CHX Dose related plaque inhibition by CHX: 10ml of 0.2% solution (20mg) High volumes of low concentration solutions Topical application of 0.2% solutions Radio-labelled CHX - slow release of antiseptic from surfaces - prolonged antibacterial effect

15. CHLORHEXIDINE PRODUCTS Mouth rinses Gels Sprays Toothpastes Varnishes

16. MOUTH RINSES Aqueous solutions of 0.2% CHX (used as 10 ml rinse) Other available concentrations: 0.1% , 0.12% (recommended as 15 ml rinses) Both these provide the equal efficacy when used in equivalent doses

17. DOSAGE AND ADMINISTRATION: Recommended use is twice daily oral rinsing for 30 seconds after tooth brushing Usual dosage is 15 ml of undiluted CHX rinse Patient should be instructed not to rinse with water or brush teeth immediately after CHX oral rinse Care should be taken to avoid ingestion of the rinse

18. GELS Available as 1% , 0.2% and 0.12% gels Delivered in tooth brushes and trays For handicapped individuals, tray delivery has been found to be effective against plaque and gingivitis DISADV: Ineffective delivery by tooth brushes Tray system of delivery is poorly accepted by handicapped patients and their care takers

19. SPRAYS 0.1% and 0.2% sprays are commercially available 0.2% spray applied in doses of 1-2 mg on all tooth surfaces produce effect similar to a 0.2% mouth rinse Useful in handicapped patients Found better accepted by such patients and their care takers

20. TOOTH PASTES Available as 1% pastes with or without fluorides Highly effective against plaque compared to other forms DISADV: High stain scores and increased supra gingival calculus formation

21. VARNISHES Used for prophylaxis against root caries

22. CLINICAL USES As an adjunct to oral hygiene and professional prophylaxis Immediate pre operative rinsing and irrigation Post-oral surgery Patients with jaw fixation For oral hygiene and gingival health benefits in mentally and physically handicapped patients Medically compromised individuals predisposed to oral infections High-risk caries patients Recurrent oral ulceration Removable and fixed orthodontic appliance wearers In denture stomatitis

23. 1) AS AN ADJUNCT TO ORAL HYGIENE AND PROFESSIONAL PROHYLAXIS CHX provides adequate plaque control following professional prophylaxis which is essential for successful treatment and prevention of recurrence

24. 2) PRE OPERATIVE RINSING AND IRRIGATION Used pre operatively for ultra sonic and high speed instrumentations Reduces bacterial load and contamination of operating area, operator and staff In susceptible patients, CHX irrigation, as an adjunct to appropriate systemic antibiotic prophylaxis, around gingival margin reduces incidence of bacteremia

25. 3) POST ORAL SURGERY Reduces bacterial load and plaque formation at times when mechanical cleaning may be difficult or is not indicated Periodontal dressings can be replaced by CHX rinsing as it provides improved healing But it is of limited use when it is used alongside a periodontal dressing CHX use is recommended throughout the treatment phase and for periods after treatment Its effectiveness also depends on time over which the non-surgical treatment is performed

26. 4) PATIENTS WITH JAW FIXATION Patients with intermaxillary fixation are prone to have an increased bacterial load along with difficulty in mechanical cleaning

27. 5) FOR ORAL HYGIENE AND GINGIVAL HEALTH BENEFITS IN MENTALLY AND PHYSICALLY HANDICAPPED PATIENTS For institutionalised mentally and physically handicapped patients, Spray delivery of 0.2% CHX has been proven to be very useful

28. 6) MEDICALLY COMPROMISED INDIVIDUALS PREDISPOSED TO ORAL INFECTIONS Patients such as those receiving chemo and/or radio therapy, bone marrow transplants immuno -compromised those including blood dyscrasias are susceptible to oral infections, most commonly, candidal infections

29. CHX is highly effective against oral infections when combined with specific anti- candidal agents such as Nystatin and Amphotericin -B In terminally ill patients, CHX sprays can be used effectively for maintenance of better oral hygiene

30. 7) HIGH-RISK CARIES PATIENTS CHX rinses and gels reduce Streptococcus mutans It has a synergistic effect with fluoride Hence, provides better anti-carious effect when combined with fluoride rinses

31. 8) RECURRENT ORAL ULCERATION CHX gels and rinses reduce incidence, duration and severity of recurrent minor aphthous ulcers by causing a reduction in contamination of ulcers thereby, reducing natural history CHX has a low therapeutic potential It shows no effect in major aphthous ulcers

32. 9) REMOVABLE AND FIXED ORTHODONTIC APPLIANCE WEARERS During the first 4-8 weeks of orthodontic treatment, plaque control will be compromised CHX also reduces the number and severity of traumatic ulcers during the first 4 weeks

33. 10) DENTURE STOMATITIS CHX gels can be applied to the fitting surfaces of the dentures – slow and incomplete resolution of the condition Can also be used in treatment of candida associated infections along with specific anti candidal drugs Less effective in therapeutic mode Denture can be sterilized by soaking in chlorhexidine solutions

34. TOXICOLOGY AND SAFETY Cationic nature of CHX minimises absorption through skin and mucosa including the gastro intestinal tract Hence, systemic toxicity from topical application or ingestion has not been reported. Neurosensory deafness can occur if CHX is introduced into the middle ear Should not be placed in the outer ear in case the ear drum is perforated

35. Long term oral use can cause a slight shift in the oral flora towards less-sensitive organisms but this is rapidly reversible Ingestion of 1 or 2 ounces of CHX oral rinse by a small child may cause signs and symptoms of gastric distress, nausea and intoxication

36. SIDE EFFECTS Taste perturbation where the salt taste is preferentially affected to leave the food and drinks with a rather bland taste

37. 2. Chlorhexidine staining 4 mechanisms have been proposed to explain CHX staining: Degradation of CHX: Degradation of CHX releases parachloraniline 2. Maillard reactions: Non-enzymatic browning reactions catalysed by CHX

38. Protein denaturation produced by CHX with the interaction of exposed sulfide radical with metal ions This theory doesn’t take into account other antiseptics and metal ions that produce staining Precipitation of anionic chromogens: Locally bound antiseptics and polyvalent metal ions react with the polyphenols on dietary substances and precipitate anionic dietary chromogens The colour of the precipitate is same as that of their metal sulfide salts

39. 3. Oral mucosal erosion appears to be idiosyncratic reaction and concentration dependent Dilution of the 0.2% formulation to 0.1% , but rinsing with the whole volume to maintain dose usually alleviates the problem

40. 4. Unilateral or bilateral parotid swelling Very rare occurrence

41. 5. Enhanced supragingival calculus formation This may be due to the precipitation of salivary proteins on to the tooth surface thereby, increasing the pellicle thickness and/or precipitation of organic salts on to the pellicle layer Pellicle formation under the influence of chlorhexidine shows as early and highly calcified structure

42. CONCLUSION Chlorhexidine to date is the proven most effective antiplaque agent It is free from systemic toxicity, microbial resistance and supra-infection Antiplaque action of chlorhexidine appears dependent on prolonged persistence of antimicrobial action in the mouth Local side effects are reported which are mainly cosmetic problems