Laser-Induced Graphene-Polyimide Film Sensor for Simultaneous Lip Electromyography and Pressure Monitoring in...

Simultaneous quantification of perioral muscle activation and lip-related pressures can support objective assessment of orofacial function, yet conventional measurements are commonly performed with separate sensors that are difficult to synchronize during dynamic tasks. Here, we present a reproducible protocol for synchronized recording of orbicularis oris electromyography (OOM-EMG), lip-closing pressure (LP), and intraoral pressure (IP) using a flexible polyimide (PI) film-based composite sensor with laser-induced graphene (LIG) electrodes and an integrated pressure-coupling pad. The protocol specifies laser patterning with prespecified electrical acceptance criteria, selective encapsulation intended for short-duration measurements, bench calibration for device-specific voltage-to-pressure conversion, standardized anatomical placement landmarks for perioral and intraoral interfaces, a task battery (lip closure, blowing, and sucking), synchronized acquisition requirements, and core signal-processing and trial-quality rules. Representative recordings in 120 healthy adults demonstrate synchronized multimodal capture under standardized conditions, with PI/LIG-derived EMG showing moderate association with conventional surface EMG (women r = 0.65; men r = 0.68) and LP strongly coupled with IP within the same task windows (r = 0.90). This method's article provides an end-to-end, replication-oriented workflow for multimodal perioral measurement in supervised research settings; validation in patient cohorts and durability under prolonged oral moisture exposure and repeated mechanical deformation should be evaluated in future studies.