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 reduce d in bottle fed babies [19]. The effects of chewing type bottle teats distributed in Japan on masticatory muscle activity were evaluated. My oelectric activities of the masseter muscles of 12 babies bottle fed w ith chewing type bottle teats were recorded and analyzed by the same m ethod as in the previous study [19]. The electromyographic records of 12 breast fed babies and 12 babies bottle fed with regular sucking typ e bottle teats, which were reported in a previous study [19], were use d as controls. The results show that the masseter muscle activity of b abies bottle fed with chewing type bottle teats was similar to that of breast fed babies qualitatively as well as quantitatively. However, a ctivity was visibly different from that of babies bottle fed with suck ing type bottle teats, showing significant difference:by ANOVA. These data suggest that babies who are ingesting milk from chewing type bott le teats do so with a chewing action similar to that of breast feeding , but very different from that of bottle feeding with sucking type bot tle teats. The conclusion was that the chewing type bottle teat is use ful for establishing masseter muscle activity.