RESUMO
The authors present a brief account of the history of dental surgery--stomatology--in Bohemia and Moravia from the very beginnings to the period after the Second World War with indicators of the brisk development of the discipline in the new democratic state which occurred in particular after the foundation of the stomatological branch of medical faculties in 1950/51. The authors mention in more detail only the main personalities and representatives of the discipline who contributed most to the development, being aware that they collaborated with several tens of teachers and research workers of more than four generations who also deserve admiration and gratitude.
Assuntos
Dentística Operatória/história , Tchecoslováquia , História do Século XX , HumanosRESUMO
The authors studied the submicroscopic structure of the human fetal periosteum. The mandible was in the 4 ..5th month of the fetal life formed of woven bone. The periosteum consisted of the cambial and fibrous layers. The cambial layer contained active osteoblasts, characterized by numerous endoplasmic reticulum profiles, flat cells with signs of osteolytic activity in their surroundings, and cells anchored to the bone matrix by their processes. From these cells the osteocytes developed. The submicroscopic structure of the young osteocytes was similar to that of osteoblasts. The fibrous layer contained numerous collagen fibres and fibroblasts, which were in the resting or active metabolic state. The results and literature are discussed in the paper.
Assuntos
Mandíbula/embriologia , Periósteo/ultraestrutura , Reabsorção Óssea , Diferenciação Celular , Colágeno , Fibroblastos/ultraestrutura , Idade Gestacional , Humanos , Microscopia Eletrônica , Organoides/ultraestrutura , Osteoblastos/ultraestrutura , Osteócitos/ultraestruturaRESUMO
The authors studied alkaline and acid phosphatase, nonspecific esterase and NADH2 tetrazolium reductase localization in the periodontium of the rat molar. The activity of all enzymes studied remained preserved in spite of decalcification in EDTA. The activity of the enzymes was relatively high, the most intense reaction was observed, with the exception of alkaline phosphatase, in the gingival epithelium. In the junctional epithelium the reaction was less intense and decreased towards the end of the epithelial attachment. Only NADH2 tetrazolium reductase exhibited high activity in this region. The periodontal ligament displayed positive reaction in all enzymes studied with the exception of alkaline phosphatase, which was active only in the dentoalveolar ligament. The results of the present study indicate that highly active metabolic processes take place in the periodontium. The results and literature are discussed in the paper.
