This document discusses chemical plaque control, specifically focusing on chlorhexidine (CHX) as an anti-plaque agent. It provides details on the ideal properties, classification, and mechanisms of action of chemical plaque control agents. The majority of the document discusses the effectiveness of different delivery methods of CHX, including mouthrinses, gels, varnishes, and combinations with fluoride, in preventing dental caries based on various clinical studies. While CHX demonstrates anti-microbial properties, the evidence from studies on its ability to prevent caries when used as a mouthrinse, gel, or varnish is mixed and inconclusive.

1. Chemical plaque
control
PRESENTED BY: ROSHNI MAURYA, 2ND YEAR PGT
DEPT. OF PEDODONTICS & PREVENTIVE DENTISTRY, GNIDSR

2. INTRODUCTION
Advancement in science & research methodologies
has helped us understand the infectious nature of
dental diseases better , which in turn has
dramatically increased interest in chemical methods
of plaque control. In addition, certain patients with
dental diseases or medical diseases require
additional assistance beyond mechanotherapy to
maintain a normal state of oral health. Moreover,
some patients are unable , unwilling or untrained to
practice effective mechanotherapy. This has
resulted in development of chemotherapeutic
agents to plaque control.

3. IDEAL PROPERTIES OF AN ANTI- PLAQUE
AGENT
 Affects only the target tissue
 Affects only bacteria known to cause gingivitis or
periodontitis or both
 Affects only the tooth or root surface and not oral mucosa
 Affects only the metabolic process of plaque bacteria
 Remains at the site of action
 Substantive effect
 Safe at concentration & dosage recommended
 Inexpensive
 Meaningful reduction in gingivitis or periodontitis or both.

4. CLASSIFICATION OF CHEMICAL PLAQUE CONTROL AGENTS:
First Generation
Antiplaque Agent(APA)
 capable of
reducing plaque
scores by about
20-50%.
 Exhibits poor
retention within
mouth.
 Ex: antibiotics ;
phenols ;
quaternary
ammonium
compounds and
sanguanarine.
Second Generation
Antiplaque Agent(APA)
 Produce an overall
plaque reduction of
around 70-90%
 Are better retained
by the oral tissues
 Exhibit slow release
properties.
 Ex: bisbiguanides
[Chlorhexidine
(CHX)]
Third Generation
Antiplaque Agent(APA) :
 They block
binding of m/o to
tooth or to each
other.
 Compared to
CHX , they do not
exhibit good
retentive
properties.
 Ex: delmopinol .

5. ON THE BASIS OF CHEMICAL COMPOSITION
TYPE AGENTS
Bis- biguanides CHX ; alexidine
Antiseptics (quaternary cetylpyridinium chloride
Ammonium compounds)
Antibiotics Penicillin;metronidazole;tetracycline;
Vancomycin; kanamycin
Enzymes Dextranase; glucose- amylogluosidase

6. Cont.……
TYPE AGENTS
Fluorides & SnF2; Chlorine dioxide; H2O2; NaCl;
inorganic ions domiphen bromide ; NaHCO3
Organic compounds Sanguanarine ; menthol /thymol
Anticalculus agents Soluble pyrophosphates

7. CHLORHEXIDINE (CHX)
 Many advances in the treatment and prevention of dental
caries have been introduced over the past century.
 The use of chlorhexidine in caries prevention has been
referred to as a non-surgical management of dental caries
and has represented the modern medical model of caries
treatment.
 However, there is a lack of consensus on evidence-based
treatment protocols and controversy regarding the role of
CHX in caries prevention among dental educators and
clinicians.
 There is a need to standardize guidelines to optimize
evidence-based non-surgical disease management to
provide appropriate care

8.  Dental caries is caused by the interplay of caries risk factors leading
to demineralization.
 Considered as an endogenous multi-bacterial infection.
 However, the presence of bacteria alone is not sufficient to cause
enamel and dentin demineralization. In the presence of a diet high in
sugar, it has been shown that subjects with high levels of S mutans
develop more caries than those with low levels of S mutans.
[Emilson, C. G. 1994. Potential efficacy of chlorhexidine against
mutans streptococci and human dental caries. Journal of Dental
Research 73 3:682–691.]
 CHX, an antimicrobial agent that can suppress the growth of mutans
streptococci, has been considered as having the potential to prevent
dental caries.
 A variety of delivery systems exist, but the only product currently
marketed in the US is a mouthrinse containing 0.12 percent
chlorhexidine gluconate.
 Due to the lack of other delivery systems with higher concentrations
of CHX, this mode is still widely recommended for caries prevention
in several caries management programs in the US

9. CHX GLUCONATE
 It is a cationic bisbiguanides
Effective against gram +ve, gram –ve organisms,
fungi, yeasts and viruses
Exhibit antiplaque & antibacterial properties

10. MECHANISM OF ACTION
Antiplaque action of chlorhexidine
1. Prevents pellicle formation by blocking acidic
groups on salivary glycoproteins thereby reducing
glycoprotein adsorption on to the tooth surface
2. Prevents adsorption of bacterial cell wall on to the
tooth surface
3. Prevents binding of mature plaques

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

12. 2. Bacteriocidal action
increased concentration of CHX
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(irreversible)

13. EFFECT OF DIFFERENT MODES IN CARIES PREVENTION
Mouthrinses
 Early studies on the effect of CHX rinses, gels and varnishes on caries
progression were reviewed by Luoma.(Luoma, H. 1992. Chlorhexidine
solutions, gels and varnishes in caries prevention. Proceedings of the Finnish Dental
Society88 3–4:147–153 )
 After these early studies, conducted more than 20–25 years ago,
there are very few published articles that describe evaluations of the
effect of chlorhexidine rinse on caries.
 One clinical study by Spets-Happonen and others, ( 1991. Effects of a
chlorhexidine-fluoride-strontium rinsing program on caries, gingivitis and some salivary
bacteria among Finnish school children. Scandinavian Journal of Dental Research 99
)where the use of periodic chlorhexidine mouthwashes was followed
over a period of two years and nine months, revealed no significant
reduction in caries.

14.  In 1989, a 0.12% solution of CHX gluconate was marketed in the US, and it is
currently the only CHX treatment mode available. There are very few clinical
studies on this CHX mode that assess the progression of caries.
A clinical study by Wyatt and MacEntee( Caries management for institutionalized
elders using fluoride and chlorhexidine mouthrinses. Community Dentistry and
Oral Epidemiology, 2004. ) evaluated the effectiveness of either a 0.25% neutral
sodium fluoride (NaF) solution or a 0.12 % CHX solution as a daily mouthrinse for
controlling caries in a two-year randomized clinical trial among the elderly in
long-term care facilities in Canada. The prevalence of caries increased in the CHX
and placebo groups, whereas there was a 24% decrease in the NaF group. The
investigators concluded that the daily rinse with 0.25% NaF solution was
significantly better than with 0.12% CHX rinse.
A double-blind clinical trial by Wyatt and others. ( CHX and preservation of
sound tooth structure in older adults. A placebo-controlled trial. Caries Research,
2007.)also tested the impact of regular rinsing with a 0.12% CHX solution on caries
in low-income elders in Seattle, WA, USA and Vancouver, Canada. The subjects
alternated between daily rinsing for one month, followed by weekly rinsing for
five months. Regular rinsing with CHX did not have a substantial effect
on the preservation of sound tooth structure in older adults.

15.  In a randomized clinical trial by Powell and others,(1999. Caries prevention
in a community-dwelling older population.Caries Research ) a weekly rinse with
0.12% chlorhexidine over three years did not reduce caries
development significantly in a low-income older subjects population.
This study was the only clinical study using 0.12% chlorhexidine rinse
that was included in the review by.( 2004. Antimicrobials in future caries
control? A review with special reference to CHX treatment. Caries Research ). His
review concluded that CHX has substantial antimicrobial properties
against caries-causing bacteria, but its use as an anti-caries agent
remains controversial.
 To be maximally effective, an antimicrobial agent must be used for a
sufficient but definite period of time. (Emilson, C. G. 1994. Potential efficacy of
CHX against mutans streptococci and human dental caries. Journal of Dental
Research ). The lesser effect on mutans streptococci and surfaces at risk
probably reflect a re-growth of mutans streptococci, because the
reservoirs in the dentition are not sufficiently affected due to the low bio-
availability of CHX from the mouthrinse solution. Staining of the teeth,
silicate fillings and the tongue, as well as disturbances of taste, raise
concerns for maintaining prolonged daily use of 0.12% CHX acetate
solution for caries prevention.

16. Gels
 Clinical studies of CHX gels have been mainly conducted on children,
and the data are promising, but sparse.
 Emilson found that studies with CHX gel treatment in high caries-risk
children showed significant reductions in dental decay. This finding
was based on the original study by Zickert and others,(1982. Effect of
caries preventive measures in children highly infected with the bacterium Streptococcus
mutans. Archives of Oral Biology) which reported a great reduction in caries
increment in children with high levels of S mutans in saliva and when
treated with 1% CHX gel trays for five minutes daily for 14 days.
 After three years, the children in the control group had developed 9.6
new caries lesions, while the treated children only developed 4.2 new
caries lesions (a 56% difference).
 Emilson's conclusions were also based on the original study by
Linquist and others, in which a 52% caries reduction was found in the
1% CHX gel group after two years, compared to the control group. In
the CHX group, children with high levels of mutans streptococci in
saliva were treated with 1% CHX gel every third month.

17. Longitudinal studies, in which the effect of chlorhexidine gel on
approximal caries was evaluated, showed significant caries
reduction ranging from 26% to 68%. For example, in a study by
Gisselsson and others,(Effect of professional flossing with chlorhexidine
gel on approximal caries in 12- to 15-year-old schoolchildren. Caries
Research ,1988) a 1% CHX gel was applied four times a year to
approximal spaces, followed by dental flossing. After three
years, the caries increment reduced significantly (52%)
compared to a control group.
A recent study by Petti and Hausen (Caries-preventive effect of
chlorhexidine gel applications among high-risk children. Caries
Research ,2006) assessed the effect of chlorhexidine gel among
three-year old children whose regular fluoride exposure came from
tooth-paste. The subjects underwent chlorhexidine gel application
for three days at three-month intervals for 15 months. The
chlorhexidine gel applications showed a moderate reduction in
mutans streptococci levels but no effect on caries prevention.
Twetman's conclusion that there is limited evidence on the
effectiveness of chlorhexidine gels and rinses in preventing caries
seems to still be current.

18. Varnishes
CHX-containing varnishes were developed to increase the
substantivity, length of the time of suppression(Clinical trial in adults of
an antimicrobial varnish for reducing mutans streptococci. Journal of Dental
Research,1991) and effectiveness of the delivery of chlorhexidine to
sites colonized by S mutans.( A preliminary report of long-term elimination of
detectable mutans streptococci in man. Journal of Dental Research ,1988)
Varnish has been shown to reduce the numbers of S mutans in
several studies. Suppression of S mutans for periods of up to five
months has been achieved by the application of a varnish
containing a high concentration of chlorhexidine (40%). (1991. Clinical
trial in adults of an antimicrobial varnish for reducing mutans streptococci. Journal of Dental
Research) Twetman stated in his review that clinical data on caries
prevention effects remain sparse and that the recent literature
was inconclusive for the use of chlorhexidine varnishes for caries
prevention in risk groups.

19.  Studies of the effect of CHX varnishes on caries in young
permanent teeth showed no statistically significant effect.
For example, Forgie and others assessed the efficacy of
chlorzoin, a chlorhexidine varnish containing 10%
chlorhexidine acetate and 20% Sumatra benzoin, in
reducing caries increment in 1,240 high-risk adolescents
aged 11–13 in a three-year clinical trial. In the first year, the
varnish was applied weekly for the first month. Patients
received a minimum of four and a maximum of six varnish
applications in the first year and a minimum of one and a
maximum of three applications in each subsequent year.
After three years, the results indicated that the use of
chlorzoin had an initial effect on S mutans levels, but no
long-term reduction in caries increment was documented.

20.  One study by Twetman and Petersson(Interdental caries
incidence and progression in relation to mutans streptococci
suppression after chlrohexidine thymol varnish treatments in
school children. ActaOdontogicScandinavia,1999) evaluated the
effect of chlorhexidine varnish treatments on both caries
incidence and lesion progression in school children with a high
risk for caries. One-hundred and ten children ages 8 to 10 years
old with moderate to high counts of salivary S mutans were
treated three times within two weeks with interdental spot
applications of 1% Cervitec varnish.
 After two years, it was found that a reduction in caries
incidence and lesion progression was clearly dependent on this
antimicrobial treatment. A significantly higher progression score
was found among children who exhibited less marked
suppression of interdental S mutans levels when compared to
those with high suppression and to the children in the reference
group. It was suggested that the suppression of S mutans in
interdental plaque might be important in preventing and
arresting approximal caries development

21.  Rozier (Effectiveness of methods used by dental
professionals for the primary prevention of dental
caries. Journal of Dental Education,2001) summarized
the evidence for the effectiveness of methods
available for caries prevention. The studies in his
review provided mixed evidence of the caries-
preventive effects of chlorhexidine used as a
varnish, and they were judged to provide
insufficient evidence of effectiveness.

22. Combinations of Fluoride and CHX
 Some clinical trials and in vitro tests have shown that the
combination of chlorhexidine and fluoride was effective
against S mutans and that the effect was synergistic
(Luoma, et al. . A simultaneous reduction of caries and gingivitis in a group
of schoolchildren receiving chlorhexidine-fluoride applications. Results after
2 years. Caries Research,1978 ) & (Ostela et al. Effect of chlorhexidine-
sodium fluoride gel applied by tray or by toothbrush on salivary mutans
streptococci . Proceedings of the Finnish Dental Society,1990)
 Chlorhexidine-fluoride gel has been shown to reduce
numbers of S mutans. It has also been shown that this
suppression effect lasts for a longer period of time than
after chlorhexidine treatment alone. However, clinical data
on the effects of caries prevention continues to remain
sparse.

23.  In a study by Katz ,a regime of four topical applications of 1.0%
NaF-1.0% chlorhexidine digluconate plus daily rinses with a
combination of 0.05% NaF-0.2% chlorhexidine solution
completely prevented radiation caries. Use of the
chlorhexidine-fluoride rinses alone also stopped radiation
caries but did not support remineralization.(. The use of
fluoride and chlorhexidine for the prevention of radiation
caries. Journal of the American Dental Association,1982)
 Petersson and others(Effect of semi-annual applications of a
chlorhexidine/fluoride varnish mixture on approximal caries incidence in
schoolchildren. A three-year radiographic study.European Journal of Oral
Sciences,1998) treated a test group of 12 year-old children
(n=115) semi-annually with a mixture of varnish containing
0.1% F (Fluor Protector) and 1.0% CHX (Cervitec). A reference
group (n=104) received fluoride varnish semi-annually.
Approximal caries was recorded from bitewing radiographs at
baseline and after three years. In this study, the differences in
caries increments were not significant, and the combination of
fluoride and CHX had no additional preventive effect.

24.  In a study by Ogaard and others,(2001. Effects of combined
application of antimicrobial and fluoride varnishes in orthodontic
patients. American Journal of Orthodontic Dentofacial Orthopedics) the
effect of CHX varnish in combination with a fluoride varnish
was compared to a fluoride varnish alone in reducing white
spot lesions in orthodontic patients. Patients received one
application of 1% CHX varnish every week for three weeks
and fluoride varnish at the next visit, six weeks later. The
patients were seen every six weeks and each varnish was
applied every 12 weeks. During the first 48 weeks of
treatment, the combination with a CHX varnish (Cervitec,
1%) significantly reduced the number of S mutans in plaque.
However, this effect did not result in significantly less
development of white spot lesions compared with the group
receiving only fluoride varnish.

25. RE-COLONIZATION
 The main clinical problem with the use of CHX is the
difficulty in suppressing or eliminating S mutans for an
extended period of time. In many clinical studies, the
organisms re-colonized the dentition. However, the re-
colonization time varied among subjects.
 In cases where S mutans had been decreased to low or
undetectable levels by the CHX gel, they generally reached
the pre-treatment levels after two to six months . The most
likely explanation for the reappearance of S mutans is their
regrowth . This suggests that there must be reservoirs or
retention sites in the dentition that are hardly affected or
not affected at all by this CHX treatment and from which
the S mutans re-colonize the dentition after treatment.
Patients with more retentive sites, such as faulty
restorations, occlusal fissures, enamel cracks, incipient
lesions or patients with orthodontic appliances, were more
rapidly re-colonized with S mutans

26. ADVERSE EFFECTS OF CHLORHEXIDINE
 Brownish staining of tooth or restorations
 Loss of taste sensation
 Rarely hypersensitivity to CHX has been reported
 Stenosis of parotid duct has also been reported
 burning sensations of the oral soft tissues,
 soreness and dryness of the oral tissues,
 desquamated lesions and ulcerations of the
gingival mucosa.

27. Triclosan
 Triclosan is a chemical that was developed nearly
30 years ago. It was first introduced into the
Health Care Services in 1972 and since then, it is
extensively used in deodorants, toothpastes,
shaving creams, mouth washes, cleaning
products, and is infused in an increasing number
of consumer products, such as kitchen utensils,
toys, bedding, socks, and trash bags

28. TRICLOSAN
 Phenol derivative
 Is synthetic and ionic
 Used as a topical antimicrobial agent
 Broad spectrum of action including both gram
positive and gram negative bacteria
 It also includes mycobacterium spores
 and Candida species IUPAC name Of Triclosan
5-chloro-2- (2,4-dichlorophenoxy)
phenol

29. MECHANISM OF ACTION
TRICLOSAN
ACT ON CYTOPLASMIC MEMBRANE
INDUCE LEAKAGE OF CELLULAR CONSTITUENTS
BACTERIOLYSIS

30.  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
 Previous studies indicate that triclosan reduces the
pain and other symptoms after chemically induced
inflammation in the oral mucosa and skin when sodium
lauryl sulfate (SLS) is used as an irritant

31. a dentifrice that contains triclosan/copolymer provides a more
effective level of plaque control and periodontal health than a
conventional fluoride dentifrice. (Evidence-Based Dentistry (2005)
6, 33).

32. Dentistry urged to take precautions with
triclosan
 Following various studies on the use of the antibacterial
agent triclosan in consumer products, including oral care,
experts are urging companies to remove it from their
formulations as a precaution.
 1) Elizabeth Salter Green, director of ChemTrust, a health
and environmental body, explained that on a precautionary
basis the chemical might not be safe to use at any level. “If
one eats the right foods and maintains correct dental
hygiene, then triclosan, or other antibacterial agents are
not needed,” explained by Salter Green.
 2) The negative effects of triclosan on the environment and
its questionable benefits in toothpastes has led to the
Swedish Naturskyddsföreningen to recommend not using
triclosan in toothpaste.

33.  Removed from GSK’s oral products Oral care giant,
GlaxoSmithKline, has removed triclosan from its Aquafresh
and Sensodyne toothpastes, as well as its Corsodyl
mouthwash, according to the University of Florida which
has performed a study on the ingredient in sheep.

34. ESSENTIAL OIL M.W.
 Contains thymol;eucalyptol;menthol;and methyl
salicylate.
 They are effective to a lesser degree than
Chlorhexidine in plaque reduction
 Causes an initial burning sensation & bitter
taste in mouth
 MOA: cell wall disruption & inhibition of bacterial
enzymes
 The most used form is Listerine.
 These products also contain alcohol.

35.  A supplement provides clear evidence that EO mouthrinses
can be a beneficial, safe component of daily oral health
routines, and a key component in oral health management.(.
Claffey N. Essential oil mouthwashes: a key component in oral
health management. J Clin Periodontol. 2003)
 The combination of fluoride and essential oils in a
mouthrinse may provide anticaries efficacy, in addition to
EO’s established anti gingivitis efficacy. There is evidence
that an essential oil mouthrinse with 100 parts per million
fluoride is effective in promoting enamel remineralization
and fluoride uptake.(The remineralizing effect of an essential oil
fluoride mouthrinse in an intraoral caries test. J Am Dent Assoc)

36. 3.QUARTERNARYAMMONIUM COMPOUNDS
 Cationic antiseptics & surface active agents
 Effective against gram positive organisms

37. MECHANISM OF ACTION
 Positively charged molecule reacts with
negatively charged cell membrane
phosphates and thereby disrupts the
bacterial cell wall structure
Eg: Cetylpyridinium chloride(0.05%)

38. Adverse effects
 Produces a yellow brownish discoloration of
tongue & around ging. Margin of tooth.
 Burning sensation
 Occasional desquamation has also been
reported

39. SANGUINARINE
 It is a benzophenanthredine alkaloid,an extract
from bloodroot plant- Sanguinalia canadenses
 Contains extract at 0.03% & 0.2% ZnCl2
 It is most effective against gram –ve organisms
 Used in mouth rinse & toothpaste
 17-42%: plaque reduction; 18-57% : gingivitis
reduction
 Causes a burning sensation when used initially

40. ENZYMES
 Employed as active agents in antiplaque
preparations as they would be able to breakdown
already formed matrix of plaque & calculus.
 Certain proteolytic enzyme are bactericidal to
m/o & would be effective when applied topically in
mouth.
 Ex: Dextranase; glucose- amylogluosidase

41. DELMOPINOL
 Is a morpholinoethanol derivative.
 Has shown to inhibit plaque growth & reduces gingivitis
 MOA:
 interferes with plaque matrix formation
 Reduces bacterial adherence
 Causes weak binding of plaque to tooth surface , aiding in
easy removal of plaque by mechanical procedures. hence,
indicated as a prebrushing mouthrinse
 Has been reputed to be effective in both rapid & slow
plaque formers; dissolves formed plaque in absence of
mechanical plaque control.

42. Adverse effects
 Transient tooth ,tongue staining
 Taste disturbance
 Sometimes mucosal soreness & erosion

43. ANTICALCULUS AGENTS
 Dentifrices containing either soluble pyrophosphatase &
zinc compounds have demonstrated 10-50% reduction in
calculus.
 MOA:
 They produce their effects by absorbing onto small
hydroxyapatite crystals, thus inhibiting growth of larger &
more organized crystals
 Mainly designed to inhibit the mineralization of so called “
petrified plaque”
 Ex: pyrophosphates; zinc citrate,zncl2 ; Gantrez ( a
copolymer of methyl vinyl & malice anhydride)

44. Sugar alcohols
 Most widely used ; xylitol; sorbitol ; mannitol;maltitol;
lacitol; their products Lycasin & Palatinit
 It is often claimed that xylitol is superior to other sugar
alcohols for caries control
 Chewing of sugar –free chewing gum 3 or more times daily
for prolonged periods of time may reduce caries incidence
irrespective of type of sugar added.

45.  Xylitol gum chewing decreased MS levels during a 13-month
intervention, while no changes were detected in the control
group. A subgroup of subjects within the xylitol group
(10/43) showed low MS levels also during the post
intervention period, demonstrating a carryover effect of
long-term xylitol use. Ishihara; Caries Res 2012;46

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48. Thank u