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== Functions ==
The digestive functions of saliva include moistening food, and helping to create a food [[bolus]], so it can be swallowed easily. Saliva contains the [[enzyme]] [[amylase]] that breaks some [[starch]]es down into [[maltose]] and [[dextrin]]. Thus, digestion of food occurs within the mouth, even before food reaches the [[stomach]].
== BacaLihat jugapula == ▼Saliva also has an important protective function, in that it helps prevent against [[tooth decay]] and [[tooth erosion]] by way of its [[buffer|buffering]] properties. Tooth decay (or erosion) progresses rapidly when the oral environment becomes [[acidic]] (eg. after consuming a soft drink or from [[fermentation|bacterial fermentation]]). [[Bicarbonate]] ions contained within saliva will act to neutralize this change in acidity, thus helping maintain a constant [[pH]]. By maintaining optimal pH levels, the rate of [[demineralisation]] (loss of tooth structure) is minimized.
Saliva also carries many important ions ([[Calcium]], [[phosphate]], [[fluoride]]) that play a role in tooth [[remineralisation]] (rebuilding lost tooth structure). The result of this is that, when acid attack occurs on a tooth, there is an equilibrium between demineralization and remineralisation. It is ideal for these two processes to occur at equal rates, however, if demineralization exceeds remineralisation, then loss of tooth structure occurs. For this reason, it is important for salivary funtion to be normal, otherwise an individual carries a higher risk of dental decay.
The importance of the salivary protective function can be demonstrated by considering a scenario where an individual is about to [[vomit]]. Vomit contains [[gastric]] substances which are extremely acidic and will erode teeth. A [[protective reflex]] occurs before the individual prepares to vomit. Signals are sent from the brain to the [[salivary glands]] (via the [[autonomic nervous system|involuntary nervous system]]) to cause increased saliva secretion, even before vomiting occurs. Thus, when vomitting does occur, there is already saliva present in the mouth acting to minimize the acidity and thus prevent destruction of tooth structure.
In addition to this, saliva is responsible for depositing [[salivary pellicle]] that covers the entirety of the tooth surfaces. This pellicle is believed to play a role in [[dental plaque|plaque]] formation, though there is evidence that it may also act as a protective barrier between acids and the tooth surface (1).
== Beliefs ==
A common belief is that saliva contained in the mouth has natural [[disinfectant]]s, which leads people to believe it is beneficial to "lick their wounds". Researchers at the [[University of Florida]] at [[Gainesville, Florida|Gainesville]] have discovered a [[protein]] called [[nerve growth factor]] (NGF) in the saliva of [[mouse|mice]]. Wounds doused with NGF healed twice as fast as untreated and unlicked wounds; therefore, saliva does have some curative powers in some species. NGF has not been found in human saliva; however, researchers find human saliva contains such [[antibacterial]] agents as secretory [[IgA]], [[lactoferrin]], and [[lactoperoxidase]]. It has not been shown that licking your wounds actually [[disinfect]]s them, but the licking action is likely to help clean the wound by removing larger contaminants such as dirt and may help to directly remove infective bodies by brushing them away.-->
==Sumber rujukan== *''[[:en:Saliva|Saliva]]'', Wikipedia edisi bahasa Inggris (18 Juli 2006) *http://www.dentistry.nus.edu.sg/cdearchive/cdeclasen.htm
*[[Lidah]]
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