Teeth mobility measurement: a laser vibrometry approach

Area of Science:

• Biomedical Engineering
• Dental Research
• Periodontology

Background:

• Traditional tooth mobility assessment relies on static loads, which are costly and difficult to implement clinically.
• Previous methods, like Muhlemann's (1967), have been validated but lacked widespread clinical adoption due to equipment and procedural challenges.

Purpose of the Study:

• To introduce and evaluate a new technique for measuring tooth mobility using dynamic loads.
• To assess the tooth displacement with a non-contact Laser Doppler Vibrometer.
• To establish a more practical and accurate method for evaluating the periodontal system's behavior.

Main Methods:

• Dynamic forces were applied to teeth using a calibrated hammer and load cell.
• Tooth displacement was measured non-invasively using a Laser Doppler Vibrometer (LDV).
• The mobility index was calculated as the ratio of peak tooth displacement to peak force.

Main Results:

• An in vitro study on extracted teeth and an in vivo study on a healthy patient demonstrated the technique's feasibility.
• Results showed good agreement with established literature values (e.g., O'Leary et al.).
• The practicality and high accuracy (sensitivity < 0.1 mm/sec) of the dynamic loading method were confirmed.

Conclusions:

• The proposed dynamic load technique provides a reliable and practical alternative for assessing tooth mobility.
• This method enhances understanding of the periodontal system's response to dynamic forces.
• Early detection of pathological tooth mobility is facilitated, potentially preventing more severe issues.