1997 Volume 22 Issue 2 Pages 114-126
Biting force may be influenced by various factors such as aging, gender, diet, mental stress, and impairment of the stomatognathic system. To address these problems, an apparatus for measuring the biting force in mice was developed. This apparatus was designed to record dynamic biting force when mice restrained in a small cylinder gnawed a transducer. This transducer consists of two parallel palatal bars (bite bar), each of which was connected to a cylindrical spring.Biting force was converted into voltage changes, amplified by a strain amplifier connected to the transducer, and recorded with a recticorder and a data-recorder. Incidence of biting and peak values of biting force curves were calculated from the data stored by the data-recorder using a wave-analysis computer.
The relation between load vs output in the transducer was highly linear (7>0.999), and reproducibility of the apparatus was very high (error of repeated measurements was lower than 0.3%). Error of position over working area was very small (lower than 1.3%).
To estimate the pattern of gnawing and maximum biting force, twelve 18-weeks old ddY male mice were used. All mice gnawed the transducer more than 100 times (minimum 124; maximum 1414) in 20 min、 Biting force curves were were comprised of spike waves, and rhythmica1 (6.0±0.4 c/s). Within 10 min from the beginning of the measurement, all mice actively bit the transducer. Mean maximum biting force was 1.20±0.06 kgw. Sum of each peak of biting force curve was 158.28±39.38 kgw.
These results suggest that this biting force apparatus can be a useful tool for the study of biting force in mice.
