Chlorhexidine is widely considered one of the most effective antiplaque agents. As a cationic bisbiguanide, it is effective against both gram-positive and gram-negative bacteria through disruption of the bacterial cell membrane. It exhibits both bacteriostatic and bactericidal properties depending on concentration. Chlorhexidine also prevents plaque formation through inhibition of bacterial adhesion to tooth surfaces and competition for calcium ions necessary for plaque aggregation. While effective, it can potentially cause tooth staining at high concentrations or dosages. Enzymes also show promise as antiplaque agents by breaking down plaque matrices and exhibiting bactericidal effects.

1. By- Dr.Prathamesh Fulsundar

2.  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.

3. 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

4. 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).

5. 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.

6. Depending on the antimicrobial efficiency and
relative substantitivity.
1st generation: decreases plaque scores by 20-
50%, but efficacy is decreased by poor
retention in the mouth. E.g. antibiotics ,
phenols etc.
2nd generation : 70-90%
more effectively retained by oral tissues
and release slowly. E.g. Bisbiguanides

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

8. 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

9. 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

10.  Phenol derivative
 Is synthetic and ionic
 Used as a topical antimicrobial
agent
 Broad spectrum of action
including both gram positive
and gram negative bacterias
 It also includes mycobacterium
spores and Candida species

11. TRICLOSAN
ACT ON CYTOPLASMIC MEMBRANE
INDUCE LEAKAGE OF CELLULAR CONSTITUENTS
BACTERIOLYSIS

12. 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

13. eg: Zn & Cu ions
MECHANISM OF ACTION
 It reduces the glycolytic activity in bacteria
&delays bacterial growth

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

15. 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

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

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

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

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

20. 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.

21. 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.

22. 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

23. 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

24. 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.

25. 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

26.  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

27.  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

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

29.  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

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

31. 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