A new sagittal dysplasia indicator: the YEN angle

Area of Science:

• Dentistry
• Orthodontics
• Cephalometrics

Background:

• Accurate assessment of maxillomandibular sagittal relationships is crucial in orthodontics.
• Existing cephalometric measurements have limitations in reliably classifying skeletal discrepancies.

Purpose of the Study:

• To introduce and validate a novel cephalometric measurement, the YEN angle, for evaluating the sagittal relationship between the maxilla and mandible.

Main Methods:

• Seventy-five lateral cephalograms from Class I, II, and III malocclusions were analyzed.
• The YEN angle was derived using specific landmarks (S, M, G) on the maxilla and mandible.
• Statistical analyses including ANOVA and ROC curves were employed to assess the angle's diagnostic capability.

Main Results:

• The YEN angle demonstrated a reliable ability to differentiate between skeletal classes.
• A YEN angle range of 117 to 123 degrees was identified as indicative of a skeletal Class I pattern.
• Specific angle ranges were correlated with Class II (<117°) and Class III (>123°) skeletal relationships.

Conclusions:

• The YEN angle provides a dependable method for assessing maxillomandibular sagittal discrepancies.
• This new measurement aids in the accurate diagnosis and classification of skeletal malocclusions.
• The YEN angle offers a valuable tool for orthodontic treatment planning.