Palatal growth studied on human autopsy material. A histologic microradiographic study.

The postnatal development of the hard palate was studied by conventional histologic and microradiographic means on autopsy material from thirty-three boys and twenty-seven girls aged 0 to 18 years. The findings indicated thet growth in length of the hard palate until the age of 13 to 15 was due to growth in the transverse suture and to apposition on the posterior margin of the palate. After this age the sutural growth was found to cease, whereas the apposition seemed to continue for some years. During the postnatal development the morphology of the transverse suture changed. At birth the suture was broad and slightly sinuous; later it developed into a typical squamous suture, the palatine part covering the maxillary part. During puberty the course of the suture was again slightly sinuous. The importance of this change for the vertical growth of the hard palate was discusses. It was pointed out that the lowering of the anterior part of the palate. The transverse growth of the midpalatal suture continued up to tha age of 16 in girls and 18 in boys. On the basis of morphology, the development of the median suture could be divided into three stages. In the first stage the suture was short, broad, and Y shaped; in the second the course was more sinuous; and in the third interdigitation was so heavy that a separation of the two halves of the maxilla would not be possible without fracturing the interdigitated processes.