我们身体的珐琅质是由羟基磷灰石（hydroxyapatite,Ca10(PO4)6(OH)2）所组成，
这是一种相当坚硬的物质，但是牙齿在遇到酸性物质（例如，口水）的时候会开始溶解，虽然牙医已经知道要利用氟化物来保护牙齿，不过这之间的详细过程却还没有清楚的定论。
Nora H. de Leeuw建立一个计算机分子动力学的模型来仿真牙齿在人体中的状况，
她发现，氟化物取代羟基磷灰石中的羟基是一种放热反应，表示这是一个很容易发生的反应，所以氟化物可以很轻易地取代羟基磷灰石中的羟基而形成氟磷灰石。不过氟化物要进入珐琅质的深处，放热的量会比在表面进行同样反应的时候来的少，所以氟磷灰石的发生会局限在珐琅质表面的部分。
而且在水分存在的状况下，氟化物不像羟基那么容易溶解在水分里，所以可以维持珐琅质的结构。另外在有水分的环境中，羟基磷灰石中的钙离子与氧离子之间的化学键会拉长，键合力量变小，而容易溶解在水中。不过氟化物除了不易溶于水之外，还可以牢牢固定珐琅质表面的钙离子，所以珐琅质就不会流失了。
虽然氟磷灰石所形成的稳定薄膜可以帮助保护珐琅质，不过在咀嚼的时候这层薄膜会逐渐的磨损掉，所以要保护牙齿必须常常使用含有氟化物的溶液来形成新的保护膜。这个发现给那些从小并未得到氟化物来照顾牙齿的人一个好消息，既然氟化物所形成的保护膜只是暂时性的存在，所以只要能有恒心地在牙齿上涂抹氟化物（例如，用牙膏），就可以维持牙齿的结构。
Our body is the enamel hydroxyapatite (hydroxyapatite, Ca10 (PO4) 6 (OH) 2) is formed
This is a very hard material, but the teeth in the face of acidic substances (eg, saliva) will begin to dissolve when, although the dentists have been aware of the need to use fluoride to protect teeth, but that are still among the detailed process is not clearly conclusion.
Nora H. de Leeuw to build a computer model of molecular dynamics to simulate the situation of the teeth in the human body,
She found that fluoride to replace the hydroxyl in the hydroxy apatite is an exothermic reaction, that this is a very vulnerable to the response, it can easily replaced by fluoride of hydroxyapatite in the formation of hydroxyl fluoride phosphate Gray stone. However, to enter the enamel fluoride in the depths of the amount of heat at the surface than when the same response to less, so the occurrence of fluorapatite will be confined to the enamel surface of the part.
But also in the presence of water conditions, fluoride and hydroxyl not so easy to dissolve in water where it can maintain the structure of enamel. Also in a water environment, in the calcium hydroxyapatite and the chemical bond between the oxygen ions will be stretched, bond together to quantitative small, and easily dissolved in water. However, fluoride addition to easily soluble in water, it can also firmly fixed the enamel surface of calcium ions, so the enamel will not be lost.
Although fluorapatite formed by the stability of the film can help protect the enamel, but in chewing time of this layer film will gradually wear out, so to protect the tooth must often containing fluoride solution to form a new protective film. This finding for those who did not receive fluoride from childhood to take care of the teeth were a good news, since the fluoride formed by the presence of protective film is only temporary, so as long as immutability carefully smear of fluoride on the teeth (for example, toothpaste) , we can maintain the tooth structure.