Lamina dura

Lamina dura is compact bone that lies adjacent to the periodontal ligament, in the

The lamina dura is a specialised component of the alveolar bone proper, characterized by thin, dense bone lamellae (cortical bone) that surrounds the tooth root. On an x-ray, a lamina dura will appear as a distinct radiopaque line surrounding the tooth root. Its structure contains numerous peforations that house blood vessels, lymphatics, and nerves, earning it the alternative name "cribriform plate". The lamina dura surrounds the tooth socket (at the tooth root), and provides the attachment surface with which the Sharpey's fibers (collagen fibers) of the periodontal ligament perforate and insert into, which is why it is also referred to as "bundle bone".

Under the lamina dura is the less bright cancellous bone, due to its mineral composition. Trabeculae are the tiny spicules of bone crisscrossing the cancellous bone that make it look spongy. These trabeculae separate the cancellous bone into tiny compartments which contain the blood-producing marrow.

Anatomically, the lamina dura transitions smoothly from the alveolar crest into the cancellous bone within the alveolar process. It is situated adjacent to three important structures: the periodontal ligament, the cementum (a mineralized tissue that provides attachment for the periodontal ligament), and the alveolar bone. Removal of the lamina dura may not be noticeable by a dentist unless the trabecular bone is also removed. An intact lamina dura is seen as a sign of healthy periodontium.This arrangement creates an integrated system that supports and maintains tooth position and function, in which it plays an important role in bone remodeling and thus in orthodontic tooth movement (along with periodontal ligament).