Oral Hygiene : Mouthwashes

Question 1

What are the basic ingredients found in mouthwashes?

Answer 1

-Water
-Alcohol (also non-alcoholic ones but are slightly less effective)
-Sweeteners
-Preservatives
-Surfactants - SLS
-Colourings - synthetic dyes

Question 2

What affect does mouthwash have on the mouth?

Answer 2

-Contains anti-plaque agents
-Prevents proliferation of plaque development

Question 3

Describe the features of chlorhexidine:

Answer 3

• Cationic Bisbiguanide

-Strong affinity to skin and mucous membranes

-works on both gram-positive and gram-negative bacteria.

-Low concentrations = Bacteriostatic (inhibits bacterial growth)

-High concentration = Bactericidal (kills bacteria)

Question 4

How does chlorhexidine work?

Answer 4

Disruption of cell membrane.

-Rapidly attracted to the negatively charged bacterial cell surface, with specific and strong adsorption to phosphate containing compounds.

Question 5

Describe the action of CHX:

Answer 5

-Binds to the different surfaces within the mouth (teeth and mucosa)

-Also binds to pellicle and saliva

-Attached to pellicle by one cation, leaving the other free to interact with bacteria attempting to colonise the tooth surface

Question 6

How long does CHX exhibit bactericidal activity for, after one rinse?

Answer 6

5 hours

Question 7

How long does CHX exhibit bacteriostatic activity for?

Answer 7

12 hours

Question 8

What are the side effects of CHX?

Answer 8

• Staining
• Altered taste
  -Burning mouth
  -Parotid swelling
  -Allergy - rare
• Oral desquamation, paraesthesia, cheilitis (inflammation of lips, perioral dermatitis.
  -Enhanced supra gingival calculus formation

look at the slides

Question 9

What concentration of CHX is available in the UK?

Answer 9

0.06% - no alcohol, daily use, designed to reduce build-up of plaque

0.2%- Intense use for specific clinical reason where mechanical plaque removal is compromised e.g after a surgery. Shouldn’t use for a long period of time

Question 10

What are other active ingredients used in mouthwashes?

Answer 10

1. Essential oil Phenolic (listerine) - Shown reduced numbers of anaerobic bacteria in plaque up to 12 h after rinsing

2.Cetyl Pyridinum Chloride (aquafresh) - Increasing rinsing freq to 4 times a day = equivalent to using chlorhexidine

3.Hydrogen peroxide - Useful for acute necrotising conditions due to effect on anaerobic bacteria.

Question 11

What is the dicationic nature of chlorhexidine?

Answer 11

• One charged end of the CHX molecule binding to the tooth surface

-The other remaining available to initiate the interaction with the bacterial membrane

Question 11

What is the key for effectiveness?

Answer 11

Substantivity - ability to bind to pellicle, tooth surface, soft tissues

look at the slides

Question 12

Why is CHX better than other mouth washes?

Answer 12

• Non-CHX have an immediate effect BUT once removed from the mouth, plaque builds up once again ( no adsorption)
• Other agents show limited persistence by one of 2 ways

1. Either lost from the tooth surface faster than CHX
2. Or bound to the surface in a way which they cannot interact with a bacterium

Question 13

What is the value of adjunctive antiseptics/chemotherapeutic agents for the management of gingival inflammation?

Answer 13

The basis of the management of gingival inflammation is self-performed mechanical removal of biofilm.

Adjunctive measures, including antiseptics, Amy be considered in specific cases or as part of a personalised approach.

Question 14

What are the BSP guidelines for overall considerations when selecting a mouthwash?

Answer 14

• Patient preferences : including cost, taste
• Unwanted effects : staining, burning sensation during use.
• Potential negative impacts on beneficial aspects of the oral micro-biome
• Potential negative impacts on blood pressure ( can slightly increase systolic blood pressure)