Erosion and Acidic Drinks

Is there evidence of acid erosion affecting some or all of your teeth.  Erosion is defined as loss of dental enamel and dentine by a chemical process which does not involve bacteria.

Erosion is progressively destructive, until  loss of tooth substance becomes clinically obvious.  First signs of the problem may be sensitivity of exposed dentine on the top of the tooth or at the gum line, or a deteriorating appearance of the teeth. Erosion is frequently associated with abrasion and attrition and these conditions may be exacerbated in the presence of erosive factors.

Clinical appearance

The earliest detectable change is diminished lustre of the tooth surface.  Continued erosion leads to smoothing out of the  developmental pits and grooves in enamel.

Advanced erosion results in exposure of dentine.  There is often extreme, intractable hypersensitivity.  In teeth with small filling, erosive loss of tooth substance results in a characteristic appearance of prominent fillings ‘standing proud’ as the surrounding tooth structure is destroyed.  Exposed dentine is less resistant to acid than enamel and so erodes faster.  The concavities on the occlusal and incisal surfaces are known as ‘cupping’.

Causes

Essentially, erosion is caused by the action of acid on the teeth often combined with a reduction in the amount of saliva present.  Saliva is our body’s natural defense against excess acid on our teeth.

Acid may come from a number of sources.

1. Diet:
   • The main source is drinks and acidic
     fruits and juices with low pH and high buffering capacity. e.g
     citrus fruits…oranges, lemons, grape fruit; also pineapples, apples etc,
     Cola-type drinks.
   • Wine is acidic:wine tasting can be a special problem.
   • Vitamin C  tablets (ascorbic acid), should not be chewed.  Food and drinks rich in vitamin C can be quite acidic.
   • Some herbal teas may be quite erosive.
2. Dental Plaque.
   • The bacterial film growing on teeth
     produces acid when there is sugar in the mouth.  This acid is usually of
     low concentration and results in demineralisation of the tooth below
     the surface (traditional tooth decay).  This source is unlikely to be a
     major contributor to erosion.
3. Gastric Acid.
   • Gastric acid reflux is said to occur
     in 80% of adults.  Symptoms such as sore throat, hoarseness, posterior
     nasal drip, sinusitis maybe associated with acid irritation of the
     throat, nose and sinuses.  Gastric reflux is more likely to occur when
     the stomach is full ( large meals including carbonated drinks ) or when
     lying down (sleeping).
   • Anorexia nervosa and bulimia nervosa
     may result in more frequent vomiting.  Other systemic problems such as
     hiatus hernia, gastric ulcer, renal dysfunction and gastritis have been
     implicated.

Saliva

Saliva has an important modifying role in erosion.  Impaired saliva function may exacerbate the progress and severity of erosion.  Saliva flow rate and buffering capacity are the two major factors to assess salivary function.

Impaired salivary flow may result from the use of prescription and non-prescription drugs including smoking and excessive caffeine and alcohol use.  Relative dehydration associated with high protein diets having a laxative and diuretic effect, strenuous exercise will effect saliva flow.

Therapy

Treatment is aimed at

• reducing acid exposure to the teeth,
• increasing saliva,
• increasing the resistance of the teeth to acid attack by increasing the amount of fluoride on the tooth surface, and
• increasing the mineral content of teeth by applying calcium cream (eg Tooth mousse, Clinpro)

Acidity of commonly available drinks:

Source: ADA Newsletter No. 241, 1997.

Drink                            EHS pH

Coca Cola regular                       3.0

Diet Coke                                    3.2

Fruitopia                                     2.8

Powerade(Orange)                    2.9

Mt. Franklin Spring Water          4.8

Cordial (diluted with Water)        3.2

Iso Sport Citrus Fruits                3.0

Iso Sports Lite Lemon Lime        3.0

Dura Fuel Isotonic Energy Drink 2.9

Gatorade Lemon Chill Flavour    2.9

Lemon Energiser Sport Drink      2.9

Lucosade Lemon                        3.4

Milk (whole milk)                          6.6

Schweppes Sports Plus              3.2

Stanley Cask Wine Riesling        3.2

Fosters Light Ice (Beer)              4.0

Victoria Bitter (Beer)                   4.2

Adalaide Tap Water                    6.8

Manufacturers pH

Coca Cola         3.0-3.5

Coca Cola         3.0-3.5

Coca Cola              3.4

Coca Cola              2.9

Coca Cola        6.5-7.5

Berrivale          3.6-3.8

Berrivale          2.9-3.3

Berrivale          2.9-3.3

Aussie Bodies        3.0

Pepsi Cola       2.9-3.3

AWD      Not Supplied

Smith Kline            3.2

Dairy Vale              6.6

Schweppes            3.0

Leasingham           3.2

Carlton&United      4.2

Carlton&United      4.2

SA Water              7.2

DR. MALCOLM J. GRENNESS
B.D.Sc., L.D.S., M.Med.Sc., PhD, F.R.A.C.D.S
DENTAL SURGEON