[Cystic lesions of the maxilla--statistical and scanning electron microscopic studies (author's transl)].

One hundred and seventeen cases of cystic lesions of the maxilla treated at Mie University hospital for 10 years from 1963 to 1972 were reviewed. Cystic lesions of the maxilla could be simply divided into, those related etiologically and anatomically to the teeth and those which were not. The former group included 24 periodontal cysts (20.6%) and 3 follicular cysts (2.6%), while the later group was composed of 73 postoperative maxillary cysts (62.4%), 10 nasoalveolar cysts (8.6%), 5 muceceles of the maxillary sinus (4.3%) and 2 nasopalatine cysts (1.8%). It is of interest that there was a little difference in incidence of nasoalveolar cyst by sex and age; most of them occurred between forties and fifties in age and there was dominant predilection for female (80% of all cases). The statistical analysis was made of the clinical history with attention to dental health, physical examination with a special concern for the nose, sinuses, mouth and the cysts. The need for complete preoperative assessment of the cystic lesions of the maxilla was emphasized. From scanning electron microscopic observations, three dimentional architectures of the cysts were characterized in the following five major types; 1) the cell surface morphologies covered with dense population of cilia with wave-like arrangement of each ciliary tuft, 2) numerous patches of the non-ciliated cell distributed among paucity of the ciliated cell, 3) the non-ciliated cells polygonal in surface outline with irregular hexogonal and pentagonal shapes arranged in mosaic pattern, 4) the non-ciliated cells with projecting domed surface covered by a lot of microvilli and 5) the conified epithelial surface with desquamating process such as overlapping cell borders, the formation of intercellular clefts and sloughing off from underlying cell layers. Correlative studies by the light, transmission and scanning electron microscopy on the same tissues will be helpful in interpreting features of the epithelial surface of the cystic lesions of the maxilla.