21. In the conducted study, it was found that hydroxyapatite growth was occurring on porous silicon areas. 22. Actually, tooth enamel is predominantly composed of hydroxyapatite , with a minor amount of organic component. 23. An acidic environment will draw the hydroxyl group out of the hydroxyapatite , causing it to dissociate. 24. One example of a hydroxyapatite cement forming reaction is that of tetracalcium phosphate and dicalcium diphosphate dihydrate: 25. Then, the hydroxyapatite crystals of enamel demineralize, allowing for greater bacterial invasion deeper into the tooth. 26. Seventy percent of bone consists of hydroxyapatite , a calcium phosphate mineral ( known as bone mineral ). 27. Several studies have shown that hydroxyapatite synthesis via wet-chemical route can be improved by power ultrasound. 28. The acids diffuse into the tooth surface and dissolve the carbonated hydroxyapatite mineral that consecutively forms a carious lesion. 29. As clay minerals promote biomineralization, the presence of bacteria and clay minerals resulted in calcium hydroxyapatite and calcite precipitates. 30. In bone removal, a reverse transport mechanism uses acid delivered to the mineralized matrix to drive hydroxyapatite into solution.
