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Observational Analysis of Discrepancy Between the Interpupillary Line and the Horizon Line in Natural Head Position
Summary
Nearly half of individuals exhibit a significant interpupillary line (IL) tilt in natural head position (NHP). This discrepancy between the IL and the horizon poses risks for inaccurate digital treatment planning in dental rehabilitation.
Area of Science:
- Dentistry
- Oral Rehabilitation
- Facial Aesthetics
Background:
- The interpupillary line (IL) is crucial for establishing esthetic and occlusal planes in facial-driven oral rehabilitation.
- Literature lacks conclusive data on the prevalence of tilted IL in natural head position (NHP) and its diagnostic implications.
Purpose of the Study:
- To determine the prevalence of discrepancy between the interpupillary line (IL) and the real horizon (HOR) in natural head position (NHP).
Main Methods:
- Calibrated facial photographs in NHP were obtained from 235 participants.
- The angle between the drawn IL and HOR was measured on each photograph.
- Participants were grouped based on the degree of angular discrepancy.
Main Results:
- A 49% prevalence of 2 degrees or more discrepancy between IL and HOR in NHP was observed.
- Specific deviations included 20.4% with 0°, 30.6% with ±1°, 25.9% with ±2°, 15.3% with ±3°, 5.9% with ±4°, and 1.7% with ±5°.
Conclusions:
- Almost half the population shows a noticeable IL-HOR discrepancy in NHP, potentially leading to inaccurate digital treatment plans.
- Reliance solely on IL for treatment planning may be risky; further research is needed.
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