 Used as adjunct to mechanical plaque control.  Many vehicles may be used to deliver anti plaque agents such as:  MOUTH RINSES,  TOOTHPASTES,  SPRAY,  IRRIGATORS,  CHEWING GUM,  VARNISHES.

Approaches to chemical supragingival plaque control: 1. ANTIADHESIVE: Prevention of attachment of bacterial biofilm. 2. ANTIMICROBIAL : by inhibition of bacterial proliferation and as bactericidal. 3. PLAQUE REMOVAL 4. ANTIPATHOGENIC

1. Should eliminate only the pathogenic bacteria. 2. Prevent development of resistant bacteria. 3. Exhibit substantivity i.e. ability of an agent to bind to tissue surfaces and to be released over time to deliver an adequate dose of active principal ingredient the agent carries. (CHX gets adsorbed to oral tissues).

4. Safe to oral tissues at concentrations and dosages recommended. 5. Significantly reduce and gingivitis and prevent colonization of microorganisms. 6. Should not stain the teeth or alter taste.

Depending on the antimicrobial efficiency and relative substantitivity. 1 st generation: decreases plaque scores by %, but efficacy is decreased by poor retention in the mouth. E.g. antibiotics, phenols etc. 2 nd generation : 70-90% more effectively retained by oral tissues and release slowly. E.g. Bisbiguanides

CHEMICAL PLAQUE CONTROL AGENTS FIRST GENERATION Eg: antibiotics, phenol,quarternary ammonium compounds & sanguinarine SECOND GENERATION Eg: Bisbiguanides,(chlorhexidine) THIRD GENERATION Eg: delmopinol

1. Antibiotics: penicillin, vancomycin 2. Enzymes: proteases, lipase, dextranase 3. Bisbiguanide: chlorhexidine, alexidine 4. Quaternary ammonium compounds: cetylpyridinium chloride, benzalkonium chloride 5. Phenols and essential oils: thymol, triclosan

6. Natural products: sanguinarine 7. Fluorides: sodium fluoride, stannous F 8. Metal salts: tin, zinc, copper 9. Oxygenating agents: Hydrogen peroxide 10. Detergents: sodium lauryl sulfate 11. Amine alcohols: octapinol, delmopinol

TRICLOSAN ACT ON CYTOPLASMIC MEMBRANE INDUCE LEAKAGE OF CELLULAR CONSTITUENTS BACTERIOLYSIS

 Triclosan is included in tooth paste to reduce plaque formation  Used along with Zinc citrate or co- polymer Gantrez to enhance its retention within the oral cavity  Triclosan delay plaque formation  It inhibits formation of prostaglandins & leukotrienes there by reduces the chance of inflammation

 Cationic antiseptics & surface active agents  Effective against gram positive organisms

MECHANISM OF ACTION  Positively charged molecule reacts with negatively charged cell membrane phosphates and thereby disrupts the bacterial cell wall structure Eg: Benzanthonium chloride, Benzalleonium chloride and cetylpyredinium

 It is a benzophenanthredine alkaloid  It is most effective against gram –ve organisms  Used in mouth rinse

 Vancomycin,erythromycin,Niddamycin and Kanamycin  Due to bacterial resistance problems the use of antibiotics has been reduced

 Considered to most effective antiplaque agents.  Second generation agents exhibiting substantivity and broad antimicrobial properties.

 It is a cationic bisbiguanide  Effective against gram +ve, gram –ve organisms, fungi, yeasts and viruses  Exhibit antiplaque & antibacterial properties

CHX due to its dicationic nature, binds to enamel pellicle or tooth surface and salivary proteins. This adsorbed CHX is released of a period of time. Mode of delivery of CHX: mouth rinse, gels, tooth paste, dental floss, and tooth picks.

Antimicrobial action and antiplaque action 1. ANTIMICROBIAL: a. at low concentration is bacteriostatic - positively charged chlorhexidine molecule will adhere to negatively charged bacterial cell surface. Integrity of cell membrane disrupted causing leakage of intracellular components. b. at high concentration is bactericidal – causes precipitation of bacterial cytoplasm so cell death.

Antibacterial action of chlorhexidine It shows two actions 1. Bacteriostatic at low concentrations Bacterial cell wall(-ve charge) Reacts with +ve charged chlorhexidine molecule Integrity of cell membrane altered CHX binds to inner membrane phospholipids & increase permeability Vital elements leak out & this effect is reversible

2. Bacteriocidal action increased concentration of chlorhexidine Progressive greater damage to membrane Larger molecular weight compounds lost Coagulation and precipitation of cytoplasm Free CHX molecule enter the cell & coagulates proteins Vital cell activity ceases cell death

ANTIPLAQUE ACTION:  Prevents formation of acquired pellicle. Blocks the acidic group of salivary glycoproteins which reduces their adsorption to hydroxyapetite.  Reduces the ability of bacteria to bind to tooth surface. Adsorption of CHX to bacterial capsule or glycocalyx and prevents them binding on to tooth surface.  CHX competes for Ca ions which are required for agglutination of plaque.

ADVERSE EFFECTS OF CHLORHEXIDINE 1. Brownish staining of tooth or restorations 2. Loss of taste sensation 3. Rarely hypersensitivity to chlorhexidine has been reported 4. Stenosis of parotid duct has also been reported

 Enzymes has been used as active agents in antiplaque preparations  It is due to the fact that enzymes would be able to breakdown already formed matrix some plaques and calculus  Some are proteolytic and have bactericidal action eg:Mucinase, mutanase, dextranase etc

 Inhibits plaque growth and reduces gingivitis Mechanism of action  Interfere with plaque matrix formation & also reduces bacterial adherence  It causes weak binding of plaque to tooth, thus aiding in easy removal of plaque by mechanical procedures  It is therefore indicated as a pre brushing mouth rinse

Adverse effect of delmopinol 1. Staining of tooth & tongue 2. Taste disturbances 3. Mucosal soreness & erosion

 A disclosing agent is a preparation in liquid, tablet or lozenge from which contains a dye or other coloring agents  A disclosing agent is used for identifying bacterial plaque  When applied to the teeth, the agents imparts its colour to soft deposits but can be rinsed easily from clean tooth surface

IDEAL PROPERTIES  Intensity of colour  Duration of intensity  Taste  Irritation to mucous membrane  Diffusibility  Astringent and antiseptic property

Agents used for disclosing plaque a. Iodine preparations Skinners iodine solution Diluted tincture of iodine b. Mercurochrome preparations Mercurochrome soln 5 Flavored mercurochrome disclosing solution c. Bismark brown d. Mebromin e. Erythrosine f. Fast green g. Fluoresin h. Two tone solutions i. Basic fuschin