POSTNATAL DEVELOPMENT OF CAT PALATE

1. 1. A histologic study of the palatal components was conducted in cats from 1 to 90 days of age. 2. 2. The hard palate of the cat consisted of three distinct bilateral growth areas-the premaxillary, maxillary, and palatine portions. 3. 3. Bone formation at the midpalatal suture of the premaxillary portion of the hard palate was limited to the intramembranous type of bone formation. No cartilage was observed at any time in the midpalatal suture of the premaxilla. 4. 4. Cartilage associated with the endochondral type of bone formation was observed at the midpalatal suture in the maxillary and palatine portions of the hard palate. This endochondral type of bone formation was active from the ages of 1 to 60 days. There were no remnants of cartilage in the suture at 90 days. 5. 5. Cartilage was observed on the maxillary surface of the premaxillomaxillary transverse suture and on both maxillary and palatine surfaces of the maxillopalatine transverse suture. There was no evidence of cartilage in the transverse sutures at 90 days. 6. 6. The posterior border of the hard palate consisted of two rounded heads of cartilage similar to the mandibular condyle. Bone growth of the endochondral type was markedly reduced by 60 days, and no evidence of any cartilaginous activity remained at 90 days. 7. 7. The endochondral type of bone growth in the palatal sutures and at the posterior border appears to be at least partially responsible for the dimensional changes produced during early postnatal palatal growth. 8. 8. The cessation of the endochondral type of bone growth appears to be related to completion of the eruption of the deciduous dentition. © 1969.