Masseter muscle activity in bottle feeding with the chewing type bottle teat: evidence from electromyographs.
It was reported that the activity of the masticatory muscles is reduced in bottle fed babies. The effects of chewing type bottle teats distributed in Japan on masticatory muscle activity were evaluated. Myoelectric activities of the masseter muscles of 12 babies bottle fed with chewing type bottle teats were recorded and analyzed by the same method as in the previous study. The electromyographic records of 12 breast fed babies and 12 babies bottle fed with regular sucking type bottle teats, which were reported in a previous study, were used as controls. The results show that the masseter muscle activity of babies bottle fed with chewing type bottle teats was similar to that of breast fed babies qualitatively as well as quantitatively. However, activity was visibly different from that of babies bottle fed with sucking type bottle teats, showing significant difference by ANOVA. These data suggest that babies who are ingesting milk from chewing type bottle teats do so with a chewing action similar to that of breast feeding, but very different from that of bottle feeding with sucking type bottle teats. The conclusion was that the chewing type bottle teat is useful for establishing masseter muscle activity.