hygiene - the international C.E. magazine of dental hygiene

26 I I trends_ patient education cludes flavorings, water, sweeteners, sugar, nonnu- tritive sweeteners, acids, citric acid, phosphoric acid, carbondioxide,sulfurdioxide,coloringadditivesand preservatives.5 Thesodapopoftodaycontainsmanyingredients, but it is the phosphoric acid that can lead to acid erosion. Why is phosphoric acid necessary in soda? In order to understand the soda connection to dentinal hypersensitivity, let’s first consider the chemicalsinsodathatcanattributetotoothsensitiv- ity.Asdiscussedinthepreviousquestion,carbonated beverages contain many ingredients, but the acids are added to buffer the beverage and offset the sweetness of the sugar. Phosphoric acid is an acidulant, i.e. a substance added to food and beverages to lower the pH and to give it a tart, acidic taste. Phosphoric acid along with carbondioxideisaddedtoretardthegrowthofmolds andbacteriathatcangrowinasugarysodasolution. Phosphoricacidisalsoaddedtokeepthecarbonated bubbles from going flat.6 With many different beverages on the market, what is the difference between the pH of these beverages? The pH of a beverage will range from a pH of 0, which is very acidic, to a pH of 14, which is very basic. A pH of 7 is our typical value for neutral. The pH of water is around 7, while the average soda pH is around 3 and sometimes less. Most carbonated beverages have a pH of 2.5 with the diet colas on average around 3.3. Studies done on acidic foods and beverages as risk factors for enamel erosion reported that most acidic beverages at a pH level of 4.2 is minimal, but became more evident as the pH was lowered.7 This lowpHsolutionbathesthetoothcontinuallyandcan potentially cause dentinal hypersensitivity because of to dental erosion. Howcansodaleadtodentinalsensitivity? The exposure and bathing of the tooth to acid over a long period can cause a progressive loss of enamel and eventually dentin. If the patient has exposed dentin at the cervical third of the tooth, this added acid process could quickly cause dentinal hypersensitivity. DrinkingalowpHbeveragecanleadtosensitivity in two ways. First, the lower pH of the beverages can keep the patient’s mouth in a constant acidic state, increasingtheriskfordentinalhypersensitivity.Sec- ond,beveragesareusuallyconsumedcoldorwithice, which also can cause the patient to experience signs and symptoms of sensitivity. Typically, dentin will have a smear layer or micro- crystalline and organic debris that is found on the root after instrumentation, brushing or due to the formation of acquired pellicle. When the acid from beverages is constantly surrounding the tooth, this smear layer is removed, which opens the dentinal tubules,thusallowingfluidtoflowinandouttoward the pulp and resulting is discomfort and pain. This process is known as the Hydrodynamic Theory.8 This theory suggests that stimuli move fluid in or out of the dentin, and that this fluid activates inter- dentalorpulpalnervestocausepain.Whenthetooth does not have a smear layer to cover the dentinal tubules, this fluid can move freely. The migration of gingival tissue due to gingivitis and or periodontal disease can also cause the root to be exposed to the fluids we drink daily. Truedentinalsensitivityismultifactorial.Thecon- stant acid environment is just one of these factors. In essence, there is not a true sensitivity caused by just soda. However, we can rule out the possibility of the patient’s diet having an over-abundant amount of acid-containing soda in his or her diet during our initial assessment phase. How can we assess the patient for soda con- sumptionanddentinalsensitivity? As with all assessment strategies in dentistry, we must first ask each patient the important questions regarding the consumption of soda and other acidic beverages.Itisimportantthattheyunderstandwhat this means and which beverages might be acidic. By providing patients with a visual chart of com- mon popular drinks, we can help them understand how these drinks can be the cause of sensitivity. A laminated beverage chart is a clearly understood and convenient source of information about these beverages.9 Many patients are not aware of the connection between these popular beverages and how the pH hygiene 1_2012 Soda pop was originally expected to be good for a person. That perception has changed over time. (Photo/Provided by www.sxu.hu)