It is one of the oldest and broadest of the engineering disciplines. The mechanical engineering field requires an understanding of core areas including mechanics, kinematics, thermodynamics, materials science, structural analysis, and electricity.
Dura mater. Dura mater (UK /ËdjÊÉrÉ ËmeÉªtÉr/ or US /ËdÊÉrÉ ËmÃ¦tr/), or dura, is a thick membrane that is the outermost of the three layers of the meninges that surround the brain and spinal cord. It is derived from mesoderm. The other two meningeal layers are the arachnoid mater and the pia mater.
Lamina dura is bundle bone that lies adjacent to the periodontal ligament, lining the tooth socket. The lamina dura surrounds the tooth socket and provides the attachment surface with which the Sharpey's fibers of the periodontal ligament perforate. On an x-ray a lamina dura will appear as a radiopaque line surrounding the tooth root. An intact lamina dura is seen as a sign of healthy periodontium. Lamina dura, along with the periodontal ligament, plays an important role in bone remodeling and thus in orthodontic tooth movement.