Abstract
We had already expressed the suppressive process of the pneumatization in experimental studies using pigs and it has been clear that the middle ear inflammatory condition suppressed the expansion of the cellulae. Last time we studied about the normal human's fetal middle ear and it was found that there were two processes of the bone metabolism of pneumatization. One of these process was the bone metabolism with absorbing the spongia bone of cortex and changing these bone to the trabecular bone by many osteoclasts and osteblasts. This process of the pneumatization was very active and it was observed in the mastoid cavities, corresponding to the inner side of the expanding mastoid process. So this time we investigated about the pig's fetal middle ear to study about the normal process of the pneumatization of pig and it was clear that the normal process of the pneumatization of fetal pig was exactly same as the active process of the pneumatization which was observed in the human's cases. So it was naturally considered that the suppressive process of the pneumatization which was found in the experimental studies of pigs will also occur in the human temporal bone.
