Fiber Bragg grating-based method for measuring mesiodistal tooth displacement and force under physiological...

Area of Science:

• Biomedical Engineering
• Dental Mechanics
• Optical Sensing

Background:

• Real-time measurement of tooth displacement and force presents a significant challenge in dentistry.
• Existing methods lack the precision and real-time capabilities required for dynamic biomechanical analysis.

Purpose of the Study:

• To develop and evaluate a fiber Bragg grating (FBG) sensor system for real-time measurement of mesiodistal tooth displacement and force.
• To assess the system's performance under physiological conditions for orthodontic and dental function applications.

Main Methods:

• Integrated a fiber Bragg grating (FBG) sensing element into a nickel-titanium orthodontic archwire.
• Bonded the FBG-integrated archwire to maxillary central incisors for in vitro and in vivo testing.
• Decoded FBG wavelength shifts to quantify mesiodistal displacement and force.

Main Results:

• In vitro testing showed a linear response between applied force and measured displacement/force.
• Under a 1 N load, the system detected 0.07±0.02 µm displacement and 0.20±0.07 N force.
• In vivo validation with volunteers demonstrated distinct biomechanical patterns during various food-related tasks.

Conclusions:

• The FBG sensor system provides stable and feasible real-time biomechanical monitoring in the oral environment.
• This quantitative optical sensing tool is valuable for studying orthodontic mechanics and dental function.
• The system successfully captured dynamic intraoral forces and tooth movements.