Two-dimensional jaw tracking and EMG recording system implanted in the freely moving rabbit.
A system for simultaneously recording mandibular position in the sagittal plane together with masticatory muscle activity was designed and tested in rabbits. Two small magnetic sensors were implanted in the maxillary bone and a powerful magnet made of a rare earth metal attached to the mandibular central incisors. The magnetic sensors detected the mandibular movements in the sagittal plane by movement of the magnet. Masseter EMG was recorded by fine wire electrodes and amplified by a specially designed amplifier. The necessary preamplifiers were assembled as an integrated circuit (IC) chip in a small housing. The signals from the preamplifier were then passed through a signal processing unit and taped on an instrumentation tape. The system was applied to the freely moving rabbit supplied with food and water during the night. It worked without any trouble for more than 24 h. Since the implanted magnetic sensors were stable for more than 4 months, long-term recording could be done by merely reimplanting the magnet, the cables and the EMG electrodes, which was simple.
Yamada
Y
Y
Department of Oral Physiology, School of Dentistry, Nagasaki University, Japan.
Haraguchi
N
N
Oi
K
K
Sasaki
M
M
D000818:Animals; D004576:Electromyography / Q000295:instrumentation* / Q000379:methods; D008334:Mandible / Q000502:physiology*; D008409:Mastication; D008410:Masticatory Muscles / Q000502:physiology*; D011817:Rabbits