Study On The Expression Of Bone Metabolic Factors Related To Different Women Menstrual Cycle Induced By Orthodontic Force

To investigate exerted force in different phases of the femalemenstrual cycle, the changes of estrogen(E2), OCN, receptor activator ofNF-kappa B ligand (RANKL) and OPG levels in the gingival crevicularfluid（GCF）during orthodontic tooth movement. provides theoretical basisto choose the best opportunity of efficient tooth movement.Methods：1.24women (age18-28) with extraction of the first premolars hasbeen selected. Randomly selected12of them as the menstrual period group,the remain12people as ovulation period group.2. Right canines were retracted with150g NiTi close coil spring.3. Gingival crevicular fluid (GCF) sample were collected at beforeforce exerted (T0),14days(T1),28days(T2) and42days(T3) later.4. The levels of E2, OCN, RANKL in GCF were measured bychemiluminescence and enzyme-linked immunosorbent assay.Results： 1. The E2、OCN levels was significantly higher in ovulation periodgroup than those in menstrual period group（P＜0.05), there aresignificant difference between all time point（P＜0.05).2. no significantly difference was found in RANKL and OPG levelsbetween two groups（P＞0.05). but significant difference wasfound between all time point（P＜0.05).3. no significantly difference was found in RANKL/OPG ratiobetween two groups.（P＞0.05)Conclusions： exerted force on teeth in menstrual period Maypromote rapid tooth movement because of the low level of E2and OCN.