Circadian Rhythm Changes Of The Levels Of Insulin In Growing Rat Lateral Pterygoid Muscle After Functional Mandibular Protrusion

Objective: In order to determine which time of the day is best to wear functional appliances and if It is the longer the better to wear functional appliances. the author investigates the circadian rhythm of the level of endogenous Insulin in growing rat condylar cartilages and the changes after functional mandibular protrusion in daytime (8 :00～20 :00) or all the day (00:00～24 :00) .Method: 72 4-week-old Wistar rats were divided equally and randomly into 3 groups , including the control group , the 12- hour wearing group , and the 24- hour wearing group. the rats in the 12- hour wearing group were put on the functional appliances in daytime (8 :00～20 :00) and the 24- hour wearing group were put on the functional appliances all the day (00 :00～24 :00) . After 7 days , all rats were sacrificed at 0 :00 , 4 :00 , 8 :00 , 12 :00 , 16 :00 , 20 :00 in a day. Endogenous Insulin level in lateral pterygoid muscles were measured by using radioimmunoassy. Dates were processed using macroscopic and microscopic analysisResults: 1 Fitting equations and characteristic values of the control group and the experimental groups 1.1 Fitting equation and characteristic values of the control groupFitting equations of the control group is Yi=32.1+5.3cos(15 ti+177). Mesor:32.1 amplitude:5.3 acrophase: 177°.p<0.051.2 Fitting equation and characteristic values of the 12-hour wearing groupFitting equation of the control group is Yi=37.1+6cos(15 ti+185). Mesor:37.1,amplitude:6.0,acrophase: 185°.p<0.051.3 Fitting equation and characteristic values of the 24-hour wearing groupFitting equation of the control group is Yi=39.6+5.7cos(15 ti+188). Mesor:39.6,amplitude:5.7,acrophase: 188°.p<0.05 2 Comparison of characteristic values between the control group and the 12-hour wearing groupComparison of characteristic values between the control group and the 12-hour wearing group and find out that there was statistically significant difference of 1 variable which is Mesor.the Mesor of the 12-hour wearing group is higher than the control group. there were no statistically significant differences of 2 variable which are amplitude, acrophase3 Comparison of characteristic values between the control group and the 24-hour wearing groupComparison of characteristic values between the control group and the 24-hour wearing group and find out that there was statistically significant difference of 1 variable which is Mesor.the Mesor of the 24-hour wearing group is higher than the control group. there were no statistically significant differences of 2 variable which are amplitude, acrophase.4 Comparison of characteristic values between the 12-hour wearing group and the 24-hour wearing groupComparison of characteristic values between the 12-hour wearing group and the 24- hour wearing group and find out that there was statistically significant difference of 1 variable which is Mesor.the Mesor of the 24-hour wearing group is higher than the 12-hour wearing group. there were no statistically significant differences of 2 variable which are amplitude, acrophase.Conclusion: 1 The growth and reconstruction degree of rats is not consistent in daytime and evening,It is displayed a significant circadian rhythm.The the growth and remodeling of lateral pterygoid muscle faster in daytime, and it is weak at night.2 The insulin content of lateral pterygoid muscle that the rats of growth and development period displayed a significant circadian rhythm. the rhythm does not disappear after wearing functional appliance 12 hours or 24 hours, the law still has a circadian fluctuations.3 The rats of growth and development period whose growth accelerate after wearing functional appliance, The insulin content of lateral pterygoid muscle increased, treatment effects which wear functional appliance for 12-hour can be generated. 4 The rats of growth and development period whose growth accelerate after wearing functional appliance, The insulin content of lateral pterygoid muscle increased, The insulin content of lateral pterygoid muscle which wear functional appliance for 24 hours increased more than for 12 hours, It is the longer the better to wear functional appliances.