انت هنا الان : شبكة جامعة بابل > موقع الكلية > نظام التعليم الالكتروني > مشاهدة المحاضرة

Environmental anomalies

Share |
الكلية كلية طب الاسنان     القسم التقويم والاطفال وطب الاسنان الوقائي     المرحلة 5
أستاذ المادة اسراء حسين علي التميمي       27/06/2019 01:57:31
They are acquired malformations of teeth that result from environmental disturbances to the tooth germ and can cause defects in tooth structure, colour or eruption.
Enamel defects may be caused by genetic or environmental factors acting alone or in combination. Enamel usually develops in two phases, first an organic matrix deposition and second mineralization. Where less enamel matrix than normal is produced, the resulting enamel will be thinner (hypoplasia). If there is a defect in mineralization of the enamel matrix proteins, the result will be poorly mineralized enamel (hypomineralization—sometimes subdivided into hypocalcification for more severe defects and hypomaturation for milder changes). In many cases there will be a combination of both hypoplasia and hypomineralization, although sometimes the defect will be perceived clinically as predominantly one or the other. When enamel hypoplasia is seen the enamel may be either uniformly thin or grooved or pitted. In hypomineralization, the enamel will typically be discoloured, usually a yellow-brown colour, weak and prone to breakdown. This is particularly so where the defect is more severe (hypocalcification), whereas in a less severe presentation (hypomaturation) the enamel may be almost normal but appear mottled or even only slightly opaque rather than translucent.
1- Localized enamel hypoplasia (Turner’s hypoplasia):
One or more permanent tooth-germs may be affected by infection from an overlying primary predecessor. Such teeth are termed Turner teeth and typically have areas of enamel hypoplasia and/or enamel hypomineralization. The mandibular premolars are most commonly affected.
A traumatic blow to an anterior primary tooth that causes its apical displacement can interfere with matrix formation or calcification of the underlying permanent tooth. The trauma or subsequent periapical infection frequently produces localized enamel defects on the labial surface of the permanent incisor

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 .
download lecture file topic