peak on the order of 104 days (over 250 years). Surface reactive bioceramics, such as Hench’s Bioglass, (Hench et al. 1971) have a
substantially higher level of reactivity peaking on the order of 100 days
TABLE 2.1 Categories of ceramic biomaterials Category Example
Inert Al2O3
Surface Reactive Bioglass
Resorbable Ca3(PO4)2
Resorbable bioceramics, such as tricalcium phosphate, have even higher levels of reactivity peaking on the order of 10 days. This broad spectrum of chemical behavior has led to a corresponding range of engineering design philosophies.
The history of bioceramics was reviewed in some detail by Hulbert, et al. in the early 1980’s.The first widely evaluated bioceramics was common
plaster of Paris, CaSO4 • H2O. Dreesman published the first report on the use of plaster of Paris to repair bone defects in 1892 (Hulbert et al. 1982–83). Extensive studies of plaster of Paris for such applications continued through the 1950’s.(Peltier et al. 1957). Attractive features of this material included little or no adverse tissue reaction and its replacement by new tissue at a rate comparable to its absorption by the physiological system. These advantages were offset by an inherent weakness and a rapid degradation in strength during absorption. This tradeoff between good physiochemical behavior and poor mechanical performance has been characteristic of many biomedical applications of ceramic materials
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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