48. Plaque Control Flashcards
UK oral hygeine market is worth … per annum
over 1 billion
Oral care products
- varnishes (chlorhexidine, thymol)
- sprays
- chewing gums - xylitol
- fluoride containing products
How have toothpastes developed?
- started as powders then pastes
- abrasives (silica, aluminium hydroxide)
- added fluoride from 1890s
Ingredients of toothpastes
- surfactant (froth and foam)
- fluoride
- antibacterial agent (triclosan, metal salts, chlorhexidine, essential oils)
- flavours
- remineralizers (hydroxyapatite)
- random things like glycerol, sodium polyphosphate, diethylene glycol in China until 2007, arginine
Arguments for mouthrinses
- plaque causes disease, contains microbes in numerous amounts that rapidly multiply
- eradication by mechanical means is near impossible
- use of chemical antimicrobials will reduce the oral load of microbes and alleviate disease
Arguments against chemical mouthrinses
- adverse effects on microbial ecology of mouth
- lazy
- efficacy
- other measures like diet, fluoride toothpaste, good prophylaxis are more effective
Explain the Plax case study
- original claim in late 1980s
- Colgate Plax - a pre-brush rinse which removes more plaque, combination of CPC and SLS, Bungay Scientific then Pfizer
- massive impact, claims not supported by clinical trials
- Pfizer subjected to class action suit in Alabama - has made misrepresentations concerning dental rinses Plax
Antimicrobial chemicals used in UK
- iodine
- sanguinarine
- chlorhexidine
- hexetidine
- triclosan
- sodium Lauryl sulphate
- thymol
- cetylpyridinium chloride
- metal fluorides
Phenolic mouthrinses
- Listerine
- Sainsbury’s Antiseptic Mouthwash with Fluoride
- and Sains Oral Health Extra
- Strength Antiseptic Mouthwash etc
Define ‘substantivity’
persistance of antimicrobial activity on oral surface
How does chlorhexidine work?
- bisbiguanide (cationic - attracted to negative charge)
- disrupts cell membrane phospholipids
- high substantivity - up to 12 hrs
- used in handwash in surgery and wipes
Chlorhexidine acts against what?
- antibacterial against fungal infections
- reported antiviral activity
- broad spectrum - gram neg and pos
- bacteriostatic at low concs, bacteriocidal at higher
How does chlorhexidine affect cell membranes?
- positively charged molecules interacts with negatively charged bacterial wall components
- destablises cell walls
- disrupts cell membranes
- disintegration of cell membranes
- cell lysis
How should chlorhexidine be administered?
- 2x daily rinse with 0.2% solution
- plaque growth completely inhibited
- gingivitis inhibited
- efficacy confirmed in many studies
- 0.12% and 0.05% available (Eludril/Chlorohex)
Problems with chlorhexidine
- tooth staining/iron salts
- taste
- allergy
Triclosan is what chemical?
polychlorophenoxyphenol
Properties of triclosan
- lower substansivity compared to CHX (co-polymer added)
- lipid soluble (penetrates skin and mucosa)
- antiphlogistic - reduces inflammation
Targets of triclosan
- broad spectrum antimicrobial
- targets lipid synthesis/enoyl reductase
- inhibits glycolysis (lactate dehydrogenase/pyruvate kinase)
- inhibits H+-ATPase (cellular pH falls)
Triclosan demonstrates efficacy against …
gingivitis
Claims by Colgate regarding triclosan
- gingivitis occurs in the presence of plaque - mainly consisting of bacteria
- Triclosan is antibacterial and therefore has a beneficial effect on gingivitis
- strongly emphasizes it’s not a replacement for regular professional dental care
How does hydrogen peroxide mouthwash work?
- an oxidising agent
- oxygenating action
- useful in managing necrotising gingivitis
What is listerine made of and development?
- blend of essential oils with antiseptic properties
- used to be in 19th century as floor cleaner, took off in 1920s when Listerine invented halitosis
What do the Medicines and Healthcare products Regulatory Agency do?
- regulates all medicines and medical devices in UK
- makes sure they’re safe and effective
What do European Medicines Agency do?
- regulates medicines and medical devices
- efficacy of medicine requires evidence that works against a disease (e.g specific date on caries or periodontitis)
What do the European Food Safety Authority do?
- regulate food supplements (includes additives to cosmetics such as on-fluoridated toothpastes)
- requires efficacy in terms of function or disease risk reduction but NOT disease
What do the Advertising Standards Authority say?
ensure adverts are ‘responsible’
What do the British Dental Association do?
Trade Union/lobbying organisation
What do American Dental Association do?
a ‘patient-centered, science based and ethically drivenv association’
Which antiseptic is most effective in mouthrinses?
- chlorhexidine
- essential oils
- cetylpyridium chloride
