Radiographic interpretation

Passing through an old radiograph lecture and wanted to list a few hints:

-PDL space is thinnest near the middle of the root and wider near the alveolar crest and apex (As fulcrum is where the PDL is thinnest)
-Lamina durat is the thin radioopaque area representing the alveolus wall (Socket wall where sharpeys fibres of the PDL insert into bone). This is more dense than surrounding trabecular bone and will be thicker and more prominent with increasing occlusal stress (as a compensating mechanism)
-The crest of the alveolar bone is considered normal height if it sits within 1.5mm of the CEJ