Definition of the reference points and measurement parameters in CBCT images
| Reference points (abbreviation) and parameters | Definition |
|---|---|
| Reference points | |
| A | The inflection point from the concave glenoid fossa to the flat posterior slope of the articular eminence. |
| B | The inflection point from the convex articular eminence to the flat posterior slope of the articular eminence. |
| C | Top of the articular eminence. |
| Incisor function point F1 | Cervically located point of inflection from the convexity of the tuberculum to the concavity of the palatal surface. |
| Incisor function point F2 | Point at the intersection of the lingual concavity with the back side of the incisal edge. |
| Measurement parameters | |
| Articular angle α | Angle between A–B line and the FH plane. |
| Articular angle β | Angle between A–C line and the FH plane. |
| Condylar axis angle | Angle between the condylar axis and the midsagittal plane. |
| Superior joint space | Shortest distance between the fossa roof and the superior condylar point. |
| Anterior joint space | Shortest distance from the most prominent anterior point of the condyle to the glenoid fossa. |
| Posterior joint space | Shortest distance from the most prominent posterior point of the condyle to the glenoid fossa. |
| Anterior guiding angle | Angle between the incisor function point F1–F2 and FH plane. |
CBCT, cone-beam computed tomography; FH plane, Frankfurt horizontal plane.