Pilot validation of a piezo‑resistive gnathodynamometer for maximum voluntary bite force measurement in adults: a cross sectional comparative study
摘要
Maximum voluntary bite force (MVBF) is a key indicator of masticatory system function, influenced by cranio-mandibular biomechanics, neuromuscular coordination, and dental status. Conventional bite force devices, though widely used, are limited by their bulk and potential discomfort during use. This study aimed to clinically validate a customized gnathodynamometer based on a piezo-resistive force sensor (Tekscan Flexiforce A-401) against a conventional strain gauge device.
MethodsAn analytical cross-sectional comparative study was conducted among 120 healthy participants (15–75 years). Bite force was measured at the right first permanent molar using both devices, with three repeated trials at 5-min intervals. Calibration was performed using NABL-accredited services, with sensor replacement after every 40 recordings to mitigate wear-related fatigue. Statistical analyses included Pearson’s correlation, Bland–Altman plots, and intraclass correlation coefficients.
ResultsBoth devices demonstrated excellent reproducibility (r > 0.98). The piezo resistive sensor gnathodynamometer consistently recorded slightly higher bite forces across age and sex groups, attributable to its thinner profile and reduced mouth opening requirement. Bland–Altman analysis revealed a small systematic bias (-3.52 kgf) favouring the piezo resistive sensor, with narrow limits of agreement. ICC analysis confirmed excellent reliability (ICC = 0.997, 95% CI: 0.995–0.998). Males exhibited higher bite forces than females across all age groups, with peak values in the 26–35 year range.
ConclusionThe piezoresistive sensor gnathodynamometer provides accurate, reproducible, and clinically acceptable MVBF measurements in healthy adults with normal dentition. Its ergonomic design and reliability support its use as a practical alternative for research applications. However, clinical utility in patient populations like temporomandibular disorders, prosthodontic rehabilitations, or periodontal disease remains to be established, and future studies are needed to validate its performance in these contexts.