Onset and Risk Period of Functional Sound Tooth Loss: A Hyperbolic Tangent Model

Area of Science:

• Gerodontology
• Biostatistics
• Epidemiology

Background:

• Existing analyses of age-related tooth loss lack quantification of accelerated loss onset and duration.
• Understanding tooth loss trajectories is crucial for effective preventive dental strategies.

Purpose of the Study:

• To apply a hyperbolic tangent model to functional sound tooth loss data.
• To derive clinically interpretable transition parameters for tooth loss trajectories.

Main Methods:

• A hyperbolic tangent regression model was fitted to normalized tooth loss data from 27,215 Korean adults (2010-2015).
• Data represented 10th, 25th, 50th, and 75th percentile groups.
• Model fit was compared to linear, polynomial, and logistic models using R-squared and AIC.

Main Results:

• The hyperbolic tangent model demonstrated superior goodness of fit (R² = 0.963–0.996) across all percentile groups.
• Peak tooth loss velocity (onset age) ranged from 57.3 to 85.9 years, with high-risk period durations (2c) from 9.8 to 17.6 years.
• Onset age (b-c) varied from 47.4 to 68.3 years, with narrow 95% confidence intervals.

Conclusions:

• The hyperbolic tangent model offers a concise 2-parameter characterization of tooth loss trajectories.
• Identified onset ages and high-risk durations enable percentile-specific risk stratification for dental care.
• Findings provide population-level estimates for oral health planning.