幼犬에 있어서 上顎의 外傷에 의한 永久齒의 發育障害에 관한 一例(豫報) : 解剖學的 所見에 대하여 With special reference to some anatomical findings = A Case of Developmental Disturbance of Permanent Teeth Due to Trauma of Upper Jaw in Puppy(A Follow-up Report)

다국어 초록 (Multilingual Abstract)

The present report is based on a thorough examination of the anatomical findings in a slaughtered puppy(a German shepherd sixteen months old), which, six weeks after its birth, fell on a concrete floor from a hight of about 50cm and contracted trauma in the upper jaw, causing a small amount of epistaxis and also the fracture of the first incisors on both sides. Some of the results thus obtained are as follows :
1, The soft tissue(or gingivae) around the incisors had a high degree of hardness owing to the proliferation of connective tissue and epithelial cell.
2. Teeth were missing in the inside of the alveolar bone in the region of the first incisors on bothsides. Scattered dental material and fatty material (?) were observed in the osseous substance which was forming an, irregular lacuna.
3. True to the radiographical fnding noted in the preliminary report, the second incisors on both sides were hidden from view, putting on the appearance of the microdontia of 0.3x0.8 cm.
4. Among the histological characteristics of the microdontia were the underdevelopment of dentinal tubules, the formation of secondary dentine or irregular dentine, a complete lack of enamel and peridental membrane, and the turbidity of the odont oblast layer within the pulp cavity.
5. A cyst was formed around the root of the left-hand second incisor.
6. The left-hand canine root made a thrust into the nasal cavity by about 2 cm, and an uneven surface was observable around the dental crown and root. Histologically, Tomes's granular within the cement layer was normal, and yet the cementum became invaginated into the dentinal region.