AAST 2023 Chemical Plaque Control PDF

Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Chemical Plaque Control The use of chemical agents in the treatment of periodontal disease is an important adjunctive therapy. Chemical agents, on the other hand, could influence plaque quantitatively and qualitativ...

Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Chemical Plaque Control The use of chemical agents in the treatment of periodontal disease is an important adjunctive therapy. Chemical agents, on the other hand, could influence plaque quantitatively and qualitatively via a number of processes: 1. Antiadhesive 2. Antimicrobial 3. Plaque removal 4. Antipathogenic Adjunctive aids are aids for plaque control and cannot replace brushing, interdental cleaning or scaling and root planing, they are classified into aids for supragingival plaque control and aids for subgingival plaque control. Supragingival Plaque Control Adjunctive aids for supra- gingival plaque control Disclosing agents. Toothpaste (Dentifrices). Mouthrinses (Antiseptic mouth washes) Supragingival irrigating devices. Disclosing agents: These are agents used to demonstrate the presence of dental plaque and thus they evaluate the efficacy of the patient's home- care technique, examples of such disclosing substances are erythrosine 'wafers or tablets), fusin and fluorescin containing dye. Page 1 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Dentifrices They are used mostly in the form of pastes, although tooth powders and gels are also available. The purposes for the use of dentifrices are facilitating plaque removal and applying agents to the tooth surfaces as a therapeutic or preventive measure. The major ingredients of the tooth paste 1. Abrasives, such as silica, alumina, and calcium carbonate. Abrasives affect the consistency of the toothpaste and assist in the control of extrinsic dental staining. 2. Detergents: the most common detergent used is sodium lauryl sulfate, It posses both antimicrobial and plaque inhibitory properties. Certain toothpaste products may be added to the product such as chlorhexidine or metal salts such as strontium used in the treatment of hypersensitivity. 3. Thickeners, such as silica and gums. 4. Sweeteners, including saccharine. 5. glycerine and sorbitol to prevent drying out of the paste once the tube has been opened. 6. Flavors, e.g. mint 7. fluorides for caries prevention, but for plaque control triclosan and stannous fluoride Herbal extracts and desensitizing agents such as strontium chloride stannus fluoride, formaldehyde and sodium citrate have proved to be of little therapeutic value. Calculus control toothpastes with the active ingredient pyrophosphate are currently available. This paste may be beneficial only for supra-gingival calculus control but it does not affect subgingival calculus formation or gingival inflammation Page 2 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Mouthrinses They can be simple aqueous solutions, to be stable and acceptable in taste usually requires the addition of flavoring, coloring and preservatives such as sodium benzoate. A number of chemical agents have been used to inhibit plaque formation but they have no effect on established plaque. These commonly used agents include chlorhexidine, phenols (triclosan, Listerine), and povidone-iodine (Betadine). Despite the ability of numerous agents to control plaque in laboratory settings, relatively few demonstrated clinical efficacy. Failure to achieve clinical efficacy may be due to inadequate exposure time in the oral cavity or substantivity. The most effective plaque inhibitory agents in the antiseptic or antimicrobial group are those showing persistence of action in the mouth measured in hours. Such persistence of action, is termed substantivity which is dependent on several factors: Substantivity is defined as the ability of an agent to be retained in the oral cavity for extended periods with subsequent slow and sustained release of the active ingredient at effective level. Agents with low to moderate substantivety are considered as first-generation agents as phenols, stannous fluoride and quaternary ammonium compounds. To date chlorhexidine is the only agent with high substantivety because it is retained and released slowly. Chlorhexidine ( CHX ) Chlorhexidine is available in three forms, a) Chlorhexidine digluconate, b) Chlorhexidine acetate c) Chlorhexidine hydrochloride salts. Page 3 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Mechanism of action Chlorhexidine is a basic antimicrobial agent. Moreover its antiplaque property is much greater than other antiseptic agents since it is adsorbed The antiseptic action of chlorhexidine on the tooth surface over 12 hrs Chlorhexidine is a potent lipophilic broad spectrum antibacterial substance. Its positively charged molecules bind to the negatively charged cell wall, disrupting cellular osmosis and cell wall integrity resulting in cell death, but this alone does not explain its antiplaque action. The antiseptic binds strongly to bacterial cell membranes. Once adsorbed, and unlike some other antiseptics, chlorhexidine shows a persistent antibacterial action lasting for 12 hours Mechanism for inhibition of plaque by CHX 1. The effective blocking of the acidic group of salivary glycoproteins will reduce their adsorption to hydroxyapatite and formation of acquired pellicle 2. The ability of bacteria to bind to tooth surface may be reduced by adsorption of CHX to the extracellular polysaccharides of their capsule What makes it so unique?  The dicationic CHX molecule, attaches to the pellicle by one cation, to the bacteria attempting to colonize the tooth surface with the other.  This is called the ‘Pin-Cushion Effect’ This prolongs the CHX action Page 4 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 As a mouthrinse, chlorhexidine has been a number of local side effects : 1. Brown discoloration of the teeth and some restorative materials and the dorsum of the tongue. The mechanisms proposed for chlorhexidine staining is possibly related to precipitation of anionic dietary chromogens (Coffee and tea) 2. Taste disturbance where the salt taste appears to be affected to leave food and drinks with a rather flavorless taste. 3. Oral mucosal erosion. This appears to be an idiosyncratic (individual) reaction and concentration dependent. Dilution of the 0.2% formulation to 0.1%, but rinsing with the whole volume to maintain dose, usually relieves the problem. Erosions are rarely seen with 0.12% rinse. 4. Unilateral or bilateral parotid swelling. 5. Enhanced supragingival calculus formation. 6. Chlorhexidine also has a bitter taste, which is difficult to mask completely.  Chlorhexidine is useful for short periods up to 2 weeks  Chlorhexidine is available in variable forms: tooth paste, spray, gel and mouth rinse. Available preparations are 0.1 % chlorhexidine gluconate (antiseptol) and 0.12% chlorhexidine hydrochloride. (hexitol). Phenols and essential oils Triclosan is usually considered to belong to the phenol group and has been formulated into toothpaste and Page 5 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 mouthrinses. In simple solutions, at relatively high concentrations(0.2%) and dose (20 mg twice per day) Triclosan has moderate plaque inhibitory action an antimicrobial substantivity of around 5 hours. In terms of plaque inhibition, a 0.1% triclosan concentration (10 mg dose twice per day) was considerably less effective than a 0.01% chlorhexidine mouthrinse (1 mg twice per day) The activity of triclosan appears to be enhanced by the addition of zinc citrate or the co-polymer, polyvinylmethyl ether maleic acid. The co-polymer enhance the retention of triclosan whereas the zinc is thought to increase the antimicrobial activity. Only triclosan toothpastes with the co-polymer or zinc citrate have shown antiplaque activity. Triclosan toothpastes appear to provide greater gingivitis benefits in some studies than plaque reductions and this could be explained by a possible anti- inflammatory action for this agent Listerine is the oldest of essential oils products and con- tains thymol, , menthol, and methylsalicylate. The mechanism of action of essential oils appears to be by cell wall disruption and inhibition of bacterial enzymes. Other antiseptics Povidone iodine( Betadine) at 1% has a substantivity of only 60 minutes and lacks appreciable plaque inhibitory activity or action in acute infections such as acute ulcerative gingivitis. Spray Sprays have the advantage of focusing delivery on the required site. Page 6 of 7  Prof.Dr. Hala Yassin Periodontology Dept AAST 2023 Chlorhexidine sprays were found particularly useful for plaque control in physically and mentally handicapped groups Irrigators Dental irrigation devices Powered dental irrigation devices are designed to eliminate plaque and soft debris through the mechanical action of a jet stream of water. Dental irrigation with water using a pulsating irrigation device has been shown to reduce gingivitis when used to supplement mechanical plaque control Irrigation devices may be used with water or with antimicrobial agents. Page 7 of 7