Fig. 1
From: Relationship between temporomandibular joint space and articular disc displacement
Schematic diagram of the grouping of disc displacement and degree. A Normal disc position (disc-condyle angle: − 15–15°). B Mild ADD (disc-condyle angle: 16–50°). C Moderate ADD (disc-condyle angle: 51–80°). D Severe ADD (disc-condyle angle: ≥ 81°). E Posteriorly displaced articular disc (disc-condyle angle: ≤ − 16°). F Schematic diagram of five groups