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Chlorhexidine: The Gold Standard in Chemical Plaque Control

Authors:
  • RUHS College of Dental Sciences, Jaipur

Abstract and Figures

Chlorhexidine, to date is the most potent anti plaque agent. It is considered gold standard anti plaque agent, against which efficacy of other anti plaque and anti -gingivitis agents is measured. Its efficacy can be attributed to its bacteriostatic and bactericidal properties and its substantivity within the oral cavity. The antimicrobial properties of Chlorhexidine are attributed to its bi-cationic molecule, and this same property is the basis of its most common side effect, extrinsic tooth staining. Administration of Chlorhexidine requires careful clinical evaluation of clinical situation and an accurate diagnosis hence, should be applied only under professional supervision.
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Review Article
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
Chlorhexidine: The Gold Standard in Chemical
Plaque Control
Setu Mathur
1
, Tanu Mathur
1
, Rahul Srivastava
2
, Rohit Khatri
3

Introduction
      
     
 
        
      
      
      
     

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   $ 
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!"#
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 $ $ - ." $
$   
 /
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    $
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) 1      .
      &
2     
!-!
"
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(  /
*
3
ABSTRACT
Chlorhexidine, to date is the most potent anti plaque agent. It is
considered gold standard anti plaque agent, against which efficacy of
other anti plaque and anti -gingivitis agents is measured. Its efficacy can
be attributed to its bacteriostatic and bactericidal properties and its
substantivity within the oral cavity. The antimicrobial properties of
Chlorhexidine are attributed to its bi-cationic molecule, and this same
property is the basis of its most common side effect, extrinsic tooth
staining. Administration of Chlorhexidine requires careful clinical
evaluation of clinical situation and an accurate diagnosis hence, should be
applied only under professional supervision.
KEY WORDS:
Gingivitis, Chlorhexidine, Antimicrobial
1
M G Dental College & Hospital
,Jaipur (Raj.), India.
2
Modern Dental College, Indore
(M.P), India
3
Rajasthan Dental College &
Hospital ,Jaipur (Raj.), India
Received: 30-05-2011
Accepted: 22-06-2011
Correspondence to:
Dr. Setu Mathur
E – mail :
drsetumathur@gmail.com
Setu Mathur et al. Chlorhexidine
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
-##
#'4 5'#  6  7
   . 
  $    

Chemical Structure
8
  ".   '
     
  3    
.2 +*


-
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6
Fig: Chemical Structure of Chlorhexidine Molecule
9
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<
' 8:<
+ =:
Metabolism and Toxicity
<     
3
       
 $    
       
    
    8
     
    3  
      
 %3
      
       
3()*#
    >##?%$
  () *#    
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Mechanism of action
      
    :
   =,@  =@$ 
$     
 

   
   A  
 $ 
      
3       
    

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3        
3
    
     $
      
3  
     
     


   %   
8
     
 
8
    $
%     
 $    
     
    
    3 

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     
       
 8     
      

!
/     
      
9
3  %    
    
    
 
Setu Mathur et al. Chlorhexidine
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
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Chlorhexidine as gold standard
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 (  1/$ #' 
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     '#  
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'
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 #' 

!
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/$ @$  $
'#
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     
   $   
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          
 526 $
       
''
/.2
       

'+
Clinical Indications of Chlorhexidine
[2], [18], [24]
3      

        
B

$
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
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    


'2    

Setu Mathur et al. Chlorhexidine
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
+8 
   : 


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*3     
%
-  

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
8    
  
       
%    
 
       

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    

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
+2%
"D   

*2   
    

-)


      
 8    
 
 2  -.  
     F  
     
  3   

(9
2     
     
      
     
8$%$$
$ % $
$$8)/
'2     
 $  $

+2
"2
*2   $ 
  $ 

-7
Adverse Effects
[2]
      
  $   
 3
      
8
%
   3
      
        
3
     %  
9
    
     
 

/     
$    %
     

'    
     
    3 
        

+   % 
   % 
    $
  3  
%$
$  $   
     
    
     
  /    
     

Setu Mathur et al. Chlorhexidine
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
F 
      
     
'*
2       
   F  

         

F     
     
      

'-
3     
      

       
  %   

        %

Limitations of Chlorhexidine
8  

=  
      

 
8$      
       

 $ 
C
8$
 5  6  
$
   3   
    

       
     

Conclusion
&      
    $ 
     
 3   
        
     8 
    
      
3     
      

References
G 7 9      H
2'###A!!09*9**.-'
'( G$ I 3$ ( J2 5'##+6 
2   )  $
,%;%
+) 7&$ E G ; 8D D E( /
7 $- .".  5=6
       
,G2!*"9!9!'.!-
"/ =& 5!-!6 9    
9,==2"*.0'
*(=/D
      
      G D
!0#9*90!.>+
-8 8  / & D 9   
(5!-'69;$20+
0E% & /   
G2D!0+9>5'69**.
*0
>) 7<  9 ,% //$ 
)$ /  2 "

 
29(E$!!9'0".'>!
!G% /$8 ; < <$   
   9      
    G2 !>>A*9"*.
"'"
#) 8 3      G
2D!0+9>5'69->.0*
=3) 8   = G
2!009"9+-.">
'D7$(=/D3
  G 2D
!0#9*9!#.!*
+( /8 ;      
9 (3$   
( #*.
'>
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 $  $   =  
 
8F,!0"569!9#'*.#'!
*7C 2     G  
2!0"$5+69"+.*'
-D < D$ 8 ;     
     
 $ $  
   D     G
2!>9>9'!*.+#
0/D&
G2D!0+9>5690.#
>(J2,; :
        
  G 2 D !>-9
'5690".>!
Setu Mathur et al. Chlorhexidine
National Journal of Physiology, Pharmacy & Pharmacology | 2011 | Vol 1 | Issue 2 | 45 - 50
!/@8$ &;$ ,, ,$  D
; $ D ($ ( J 2$ ; ; &  ;% 8
    
   G 2 D!>-9
'569'+.+'
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      G 
2!!*9'+9!.'+
'F /$  &$ 7 2 3  
    
8F/!>!9"09+-
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... Chlorhexidine gluconate (CHG) is considered as the gold standard among antibacterial agents [6]. It is also a bisguanide known for its significant bacteriostatic and bactericidal features. ...
... It is also a bisguanide known for its significant bacteriostatic and bactericidal features. This agent has been proven effec-tive in prohibiting plaque formation and counteracting a wide spectrum of bacteria and viruses [6]. Although CHG is being broadly used, it causes mitochondrial dysfunctions (which leads to decreasing cell viability and cytotoxicity), extrinsic staining, mild mucosal irritation, alteration in taste perception, and rarely increased calculus formation [7][8]. ...
... In children, lack of dexterity and less motivation for tooth brushing would be the cause for more plaque accumulation as well as an increase in S. mutans load. Therefore, chemotherapeutic agents as mouthwashes for plaque control especially at interproximal surfaces are necessary [5][6]. ...
Article
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Statement of the problem: Camelia Sinenis or green tea (GT) and Teucrium polium (TP) are known to have a great antimicrobial potential on salivary Streptococcus mutans (S. mutans). Their efficacy should be examined compared to the gold standard antimicrobial agents. Purpose: To evaluate the effects of Camelia Sinenis or green tea (GT) and Teucrium polium (TP) extracts in comparison with chlorhexidine gluconate (CHG) on salivary S. mutans levels. Materials and method: This double-blinded randomized clinical trial study was conducted on 90 preschool children aged 4 to 6 years and assigned randomly (simple randomization) to three groups as GT, TP, and CHG. Unstimulated saliva samples were then collected in three times as before application of agents, after half an hour, and after one week. To determine S. mutans levels, quantitative polymerase chain reaction (qPCR) technique was additionally utilized. Statistical analysis was also fulfilled using Shapiro-Wilk test, Friedman test, Chi-square test, paired sample t-test, repeated measures analysis of variance (ANOVA), and Mann-Whitney U test at a significance level of 0.05. Results: The results of this study established a significant difference between mean salivary S. mutans levels after administration of the three compounds. Although the mean of S. mutans levels reduced significantly following the application of CHG and TP after half an hour, the mean salivary S. mutans levels in the group receiving GT declined in a significant manner only one week later (p< 0.05). Conclusion: The results of this study indicated that GT and TP extracts had considerable effects on salivary S. mutans levels compared with CHG.
... Following are the possible mechanisms for the inhibition of plaque by Chlorhexidine. 27 x The effective blocking of acidic groups of salivary glycoproteins will reduce their adsorption to hydroxyapatite and the formation of acquired pellicle. Laboratory studies have suggested that Chlorhexidine can bond with hydroxyapatite. ...
... x The Chlorhexidine may compete with calcium ions agglutination factors in plaque. 27 ϭϳ ...
... Due to the complex design of orthodontic brackets, mechanical methods such as brushing cannot ensure complete plaque removal [6,9]. To overcome the limitations of mechanical cleaning methods, chemical antimicrobial agents, such as chlorhexidine (CHX) and hydrogen peroxide (H 2 O 2 ), have been used for plaque control [10][11][12]. However, bacteria residing in biofilms have higher resistance to antibiotics and disinfectants than planktonic cells because the matrix produced by extracellular polymeric substances (EPS) limits the transport of antibacterial agents and neutralizes them chemically [13,14]. ...
... Therefore, chemical methods should be used as an assistant [17]. CHX has been used as a conventional chemical therapeutic agent for plaque control [10,11]. A previous study reported that CHX reduced the viability of S. mutans on brackets [17]. ...
Article
Full-text available
Background Orthodontic brackets provide a favorable environment for Streptococcus mutans biofilm formation, increasing the risk of white spots and dental caries. Manganese oxide (MnO2) nanozyme-doped diatom microbubbler (DM) is a recently developed material for biofilm removal. DM can generate oxygen by catalase-mimicking activity in Hydrogen peroxide (H2O2) solution and move with ejecting oxygen microbubbles to produce a mechanical self-cleansing effect. This study aimed to evaluate the feasibility of DM as a novel bracket cleaner. Methods DM was prepared according to the protocol and analyzed using a scanning electron microscope (SEM). We treated S. mutans biofilms grown over bracket with phosphate-buffered saline (PBS group), 0.12% chlorhexidine (CHX group), 3% H2O2 (H2O2 group), and co-treatment with 3 mg/mL of DM and 3% H2O2 (DM group). The biofilm removal effect was analyzed using crystal violet assay, and the results were observed using SEM. The viability of S. mutans in remaining biofilms was evaluated using confocal laser scanning microscopy (CLSM). Finally, we examined the effect of all materials on mature multispecies biofilms formed on debonded brackets. Results Crystal violet assay results revealed that the CHX group removed more biofilms than the control group, and the DM group removed biofilms more effectively than the CHX group (p < 0.0001). SEM and CLSM images showed that CHX killed S. mutans but failed to remove most biofilms on brackets. However, DM effectively removed biofilms and mature multispecies biofilms on debonded brackets (p < 0.0001). Conclusions Co-treatment with DM and H2O2 is effective in removing biofilms on orthodontic brackets compared to conventional antibacterial agents.
... Chlorhexidine till date is the proven most effective antiplaque agent. [16] Its efficacy can be attributed to its bacteriostatic and bactericidal properties. However, its long-term use is limited due to local side effects including extrinsic tooth and tongue brown staining, taste disturbance, enhanced supragingival calculus formation, and desquamation of the oral mucosa. ...
... However, the increase in the GCF influx after rinsing with CHX can be attributed to the fact that CHX could exhibit profound antiplaque properties only after meticulous removal of dental plaque guaranteed by toothbrushing [29]. Therefore, it might have lost its efficacy in reducing plaque accumulation during the non-brushing period of this study. ...
Article
Full-text available
Despite the antiplaque effect of mouth-rinsing with a combination composed of miswak (Salvadora persica L.) and green tea (Camellia sinensis var. assamica) extracts, no data are available regarding its effect on gingival tissue at the molecular level. This pilot study aimed to assess the effect of oral rinsing with this combination on gingival crevicular fluid (GCF) flow and IL-1β levels. Ten subjects rinsed with either the combination, 0.12% chlorhexidine gluconate (CHX) or distilled water without toothbrushing for 4 days after receiving baseline polishing. GCF IL-1β concentration, influx, resting volume and plaque quantity were measured at baseline and after 4 days for each intervention. No significant differences in GCF flow or resting volume were detected after rinsing with the different mouthwashes. A significant increase in GCF IL-1β concentration was evident only after rinsing with distilled water. Rinsing with combination induced a significant reduction in GCF influx (−0.086 ± 0.222) compared to CHX (0.088 ± 0.247) and distilled water (0.075 ± 0.201). Less plaque was detected after rinsing with combination and CHX. Short-term oral rinsing with this combination could potentially induce no significant changes in GCF flow and IL-1β concentration, and might retard inflammation. Thus, it might be considered in the production of natural oral healthcare products.
... Hence, chlorhexidine is considered the gold standard of the chemical treatment of these bacteria. [9] There is strong evidence regarding the anti-plaque activity of chlorhexidine in orthodontic patients. [10,11] Clinical studies showed a significant reduction in S. mutans level in orthodontic patients, 1 week after using chlorhexidine mouthwash. ...
... Despite Chlorhexidine's powerful antibacterial and antiplaque qualities, its broad and long-term use is limited by its well-documented local adverse effects. Extrinsic discoloration of both natural and artificial teeth is the most common local side effect encountered when used as a mouth rinse, whose severity is directly proportional to its concentration [11,12]. ...
Article
Full-text available
creative commons attribution noncommercial License. This allows others to remix, tweak, and build upon the work non commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms. Abstract Effective treatment of periodontitis requires control of subgingival plaque byScaling and rot planing, but retention of plaque in deep pockets can be a nidus for reinfection. Local administration of antimicrobial agents offer a 'site-specific' approach to periodontal therapy. 3
Article
Objective: Morning breath is a temporary and unpleasant malodour sourced from the mouth, which occurs upon awakening. This double-blind, crossover, randomized clinical trial aimed to evaluate the bad-breath suppression of 3 commercially available mouthwashes: Mentadent Professional® Chlorhexidine 0.05% with vitamin C (ChxC), Meridol Alito Sicuro® (SnF2 ) and CB12® (ZnChx) compared to a placebo (PbO) on morning halitosis. Methods: Thirty-two subjects refraining from oral hygiene practices for 12 hours before the evaluation, performed a 30-seconds rinse with 15 ml of mouthwash, followed by a 5-seconds gargle, in the evening before bedtime. In order to assess morning halitosis, visual inspection (Winkel Tongue Coating Index), organoleptic (Rosenberg index) and chromatographic measurements were used. Gas chromatography was carried out by means of a dedicated device, the Oral Chroma. The recorded measurements have to be considered solely after the rinse since no data about the pre-exposure were available. A washout period of 1 week passed between one administration and the next. Results: The mean value of the organoleptic indices after administration of ChxC mouthwash is similar to ZnChx, SnF2 and PbO values. Thus, no statistically significant differences were recorded among the mouthwashes and PbO. Nevertheless, ChxC seems to be more efficient in comparison with the PbO regarding VSCs levels analysed with Oral Chroma, (CH3 SH; p=0.0081) and [(CH3 )2 S; p=0.0003]. Conclusion: Considering our limited sample, instrumental examination demonstrated that the use of the analysed mouthwashes can result in low VSCs levels after 12 hours from a single rinse. Furthermore, the highest number of patients (n=14) were proved to be free from bad smell after using a single administration of ChxC with respect to the other commercial products. The other tested mouthwashes did not show better performances with respect to the placebo after a single rinse.
Article
Polyphenols are plant secondary products with health-promoting properties against various degenerative or infectious diseases, and thus may help in the prevention of oral diseases. The aim of the present systematic review was to investigate polyphenols as a possible adjuvant in inhibiting dental biofilm formation, which is an important precondition for the most prevalent oral disease - caries and periodontitis. A literature search was conducted using the databases PubMed, CENTRAL and Scopus. Only studies with oral healthy participants and plaque level as outcome were included. Data search and extraction was conducted by two authors independently. Of the 211 initially identified studies, only six met all inclusion criteria. Meta-analysis was performed with five studies using the random effect model. Treatment with polyphenols reduced the plaque level in comparison to a negative control, but not significantly. Strong evidence of heterogeneity was observed. The diversity and complexity of polyphenols and their preparation need to be considered. There is no clear evidence that clinical use of polyphenols can prevent dental biofilm formation. Additional research with more and larger randomized controlled trials are required.
Article
In selecting antimicrobial agents for the prevention and treatment of periodontal diseases, the following factors should be considered: 1. Specificity, 2. Efficacy, 3. Substantivity, 4. Safety, 5. Stability. Using these criteria, several antibiotics and antiseptics have been evaluated in recent years for chemical plaque control. While antibiotics are mostly used under a specific plaque hypothesis, antiseptics are more suitable for a non-specific plaque concept. Several antiseptics hinder plaque formation or even break up old plaque. For example, quaternary ammonium compounds, combinations of metal ions with pyrimidines or with fluorides, phenolic compounds, and plant alkaloids have yielded a plaque reducing effect of 20–20% and have also delayed slightly the development of gingivitis. Years of documented research have established that chlorhexidine digluconate is safe, stable, and, owing to its great substantivity, effective in preventing and controlling plaque formation, breaking up existing plaque, and inhibiting and reducing the development of gingivitis. In studies of 6 months and longer, chlorhexidine has been shown to reduce gingivitis by 50–50% compared to a placebo control. Chlorhexidine is the most effective and most thoroughly tested antiplaque and antigingivitis agent known today.
Article
Since the advent of a nondegradable controlled local delivery of antibiotics in 1979, several second generation systems have been developed. Second generation systems have attempted to improve on the early system. Chlorhexidine has been used effectively for over 30 years as an antiseptic. In the early 1970s, chlorhexidine gluconate was incorporated at 0.2% into mouthrinses in Europe and in 1986 it was incorporated at 0.12%, in a mouthrinse in the United States. Since these mouthrinses were effective in reducing the supragingival flora, had a high safety margin, and had no reported bacterial resistance, chlorhexidine offered a therapeutic advantage for a local delivery system. This system was developed and studied. This report will discuss this new biodegradable system containing chlorhexidine gluconate as the active agent (PerioChip®). Parmacokinetics of the system and a review of the multicenter studies in Europe and the United States are discussed. In these randomized clinical trials the chlorhexidine chip has been shown to enhance the effects of scaling and root planing. Chlorhexidine chip in conjunction with scaling and root planing, when compared to scaling and root planing alone, has shown significant improvement in probing pocket depth reduction, probing attachment level and bleeding on probing. This delivery system, in combination with scaling and root planing, has also resulted in significantly more probing depth reductions of 2 mm or more. The system is safe and efficacious. Placement of the chip is usually done in less than 1 min, it requires no retention system, biodegrades, and does not require a follow-up dental appointment.
Article
Abstract The key features of the interaction of chlorhexidine with bacteria leading to death are adsorption, damage to permeability barriers and precipitation of the cytoplasm. The bacteriostatic profile indicates that Streptococcus mutans is highly susceptible but it is not known whether bacteriostatic or bactericidal activity is crucial to antiplaque activity. Although some correlation overall was found between bactericidal and bacteriostatic susceptibility amongst more than 80 strains of various species, reference to the minimum inhibitory concentration alone gives no firm indication about the possible lethal action of chlorhexidine.The effects of saliva and pH on antibacterial activity are given. In human studies reported by others, repeated oral application of chlorhexidine reduced the numbers of salivary organisms recoverable and this was accompanied by slight (seemingly clinically insignificant) alterations in the sensitivity of certain salivary organisms. Daily application of a chlorhexidine dental gel in a 6‐week trial did not result in detectable changes of susceptibility of the salivary flora. Rats dosed daily in drinking water (5‐10 mg chlorhexidine base per kg) over a 2‐year period yielded buccal organisms with reduced sensitivity: this was not reflected amongst faecal bacteria. The faecal flora changed quantitatively in a dose‐dependent manner and coliform organisms particularly were reduced in number.Caution is required in interpreting relative sensitivities of different bacterial strains or species from data obtained using agar‐diffusion methods.
Article
Most commercial periodontal dressings claiming antibacterial activity lose this activity shortly after application. Chlorhexidine (CH) is an antibacterial agent with long-term activity in the oral cavity owing to its substantiveness and slow-release properties. In a double-blind split-mouth-designed clinical trial the effect of incorporating CH acetate in periodontal dressing was tested on wound healing after gingivectomy. Eleven patients, each needing at least two gingivectomies, constituted the test panel. Wound healing, as assessed by bleeding tendency after removal of dressing 7 days postoperatively was significantly delayed when control dressings were applied as compared with test dressings. Variables with regard to patient comfort also yielded results in favor of the test pack. Incorporation of antibacterial agents with high retention and slow release properties in the mouth in surgical dressings seems advantageous.
Article
Controversy exists concerning the mode of action of chlorhexidine in plaque inhibition. This study attempted to determine whether an oral reservoir of chlorhexidine was necessary for plaque inhibition. Plaque growth on enamel under the influence of topically applied or rinsed chlorhexidine was closely monitored by clinical scoring, bacterial culturing and scanning electron microscopy. Thus, 3 subjects wore removable acrylic appliances containing enamel inserts. In the first regimen, inserts on one side of the appliances were exposed to 0.2% chlorhexidine and on the other, water for 1 min twice a day for 14 days. In the second regimen, subjects rinsed with 0.2% chlorhexidine for 1 min twice a day for 14 days with the appliances in situ. Results demonstrated that plaque growth assessed by the 3 study methods was very small on chlorhexidine-treated inserts by comparison with water-treated specimens. Importantly, inserts treated with chlorhexidine topically or by rinsing could not be distinguished by any method of evaluation. It is concluded that chlorhexidine achieves plaque inhibition as a result of an immediate bactericidal action during the time of application and a prolonged bacteriostatic action as a result of adsorption to the pellicle coated enamel surface. Consistent with other clinical studies, it is apparent that a progressively desorbing oral reservoir of antiseptic is not the mechanism by which chlorhexidine achieves plaque inhibition on teeth.
Article
The oral retention of chlorhexidine-digluconate from rinsing solutions of 0.05, 0.1, 0.2 and 0.4 per cent was measured by means of [24C]-chlorhexidine. Corrections were made for the fraction swallowed by the use of [51Cr]-EDTA. The retention was essentially proportional to the concentration, with a slight deviation towards less retention at the 0.4 per cent concentration. Approximately half of the chlorhexidine retained after a 60-sec rinse was retained within the first 15 sec, and about 75 per cent within 30 sec. Increasing the temperature of the rinsing solution from 22 to 60 °C had little effect on retention. Increasing the pH of the rinsing solution from 6.4 to 9.0 did not change the retention. At pH 3.0 and 1.5 the retention was less than half of that at pH 6.4.
Article
Keywords:Chlorhexidine;plague control;prevention
Radioactive chlorhexidine † (14C labeled in the phenyl rings) was used to study absorption by and desorption From Streptococcus mulans and teeth. When S. mutans was grown in brain heart infusion broth, the rate of absorption by the bacteria was rapid, but when bacteria were grown in medium containing sucrose, absorption was slow apart from an initial rapid phase. Very slow absorption was observed by organisms grown on wire immersed in the sucrose medium. Thus there appears to have been some barrier delaying absorption when the culture medium contained sucrose. Studies with human teeth showed considerable variation between teeth but the rates of absorption and desorption were generally slow.