Characterization of primary and permanent teeth using terahertz spectroscopy

Area of Science:

• Biophysics
• Dental Science
• Spectroscopy

Background:

• Dental diagnostics often rely on invasive or ionizing radiation-based methods.
• Terahertz (THz) waves offer a non-ionizing alternative for biological tissue analysis.
• Developing novel spectroscopic methods is crucial for advancing dental imaging.

Purpose of the Study:

• To evaluate the utility of a laboratory-developed terahertz time-domain spectroscopy (THz-TDS) system for analyzing dental tissues.
• To measure the optical properties of sliced teeth sections in transmission mode.
• To investigate potential differences in THz properties between primary and permanent teeth, as well as healthy and carious teeth.

Main Methods:

• Utilized a custom-built THz-TDS system to analyze 25 teeth samples (9 primary, 16 permanent).
• Calculated refractive index and absorption coefficients from transmission measurements at 0.5 THz.
• Employed Mann-Whitney U-test to compare optical properties between different tooth groups.

Main Results:

• Median refractive index values were approximately 2.54 for all groups (primary/permanent, healthy/carious).
• Median absorption coefficients were 26.29 (permanent), 29.67 (primary), 26.52 (healthy), and 27.13 (carious).
• No statistically significant differences (p > 0.05) were observed in refractive index or absorption coefficients among the groups.

Conclusions:

• THz-TDS analysis of teeth reveals consistent optical properties across different groups.
• While no significant differences were found, THz imaging demonstrates potential as a non-destructive tool for dental structure assessment.
• Further research may refine THz-TDS applications in dentistry.