ABSTRACT
Objective: To understand the effects of different expansion ways on collagen and actin of skin and to provide an experiment foundation for the suitable expansion method clinically. Methods: The rabbits were divided into five groups. The expanders were embedded in experimental group. The sirius-red specific staining method was applied to observe the changes of type I collagen and type III collagen and their proportion. Immunochemistry method was used to detect the expression of actin. Results: 1: In group A, B and C, type I collagen arranged turbulently and was thicker and type III collagen decreased relatively at earlier maintaining period. After 4 week, type I collagen arranged regularly and type III collagen was relatively increased. 2: Comparisons of the area about type I, III collagen: At the same maintaining period, there were no significant difference among the group A,B and C. With the extension of maintaining period, the area of type I, III collagen increased gradually, but there was inclined to stabilize at the fourth week in group A, B and at the third week in group C. Comparison of the proportion of collagen I and collagen III: There were significant difference between group A, B and group D, but no significant difference was observed after the fourth week. There were significant difference between group C and control group, but no significant difference was observed after three week. 3. With the extension of maintaining period, the positive expression rates of actin decreased gradually in group A, B, C. At the same maintaining period, significant difference were observed among group A, B, C. The positive expression rates of actin in group C were lower than that of group A at the same maintaining period. Conclusion: The repeated rapid expansion can not only shorten the clinical period but also promote the quality of skin flap. It is a safe and feasible method in clinic.
ABSTRACT
OBJECTIVE: With the prolongation of life span, more and more people care their health. In this paper we summarized the studies about correlative factors of mandible osteoporosis so as to investigate the cause of osteoporosis and how to inhibit or postpone the occurrence of mandible osteoporosis and improve people's quality of life.DATA SOURCES: We searched Qsinghua Tongfang Database for papers about mandible osteoporosis published between January 1991 and May 2005 with the key words of "osteoporosis, mandible bone, alveolar bone"in Chinese. Meanwhile, related English literatures were also searched in Medline between January 1975 and May 2005 with the same key words.STUDY SELECTION: The literatures included all the related papers of correlative factors of mandible osteoporosis. Inclusive criteria were: the study types were randomized controlled trials, drug stress test and clinical drug effect test; the samples were both human and animals. Exclusive criteria: Reviews and literatures without controls were excluded.DATA EXTRACTION: Totally 182 literatures related to the correlative factors of mandible osteoporosis were collected, and 36 were accorded with the inclusive criteria. The excluded were 146 papers of repeated drug effect study.DATA SYNTHESIS: A total of 36 papers including 5 321 human and 152 animals analyzed the data of correlative factors of mandible osteoporosis in age, sex, hormones, biting force, physical training and living habit,etc., respectively, which included 6 interfere-test papers of ovariactomized rats.CONCLUSION: It is concluded that mandible osteoporosis can result in a part of bone mine loss, which is related to age, sex, hormones, biting force,physical exercise and living habits, and so on.