4Kygh P, Bowling K, Hovlandsolal I, et al. Activation of the vascular system: A main mediator of periodontal fiber remodeling in orthodontic tooth movement. Am J Orthod, 1986,89:453-468.
5Clark AB, Sim MR, Leppard PI. An analysis of the effect of tooth intrusion on the microvascular bed and fenestrae in the opical periodontal ligament of the rat molar. Am J Orthod 1991,99:21 -29.
6Bartley MH, TaylorGN, Jee WS. Teeth and mandible. Ames iowa: The Iowa state university press, 1970:189- 215.
7Pilion JGM, Jagtonan AMK, Maltha JC. magnitude of orthodontic forces and rate of bodily tooth movement: An experimental study. Am J Orthod,1996,110:16- 23.
8Burstone CJ. Chinese NiTi wire-A new orthodontic alloy. Am J Orthod,1985,96:445 - 451.
9Selliseth N J, Selvig KA. The vasculature of the periodontal ligament: A scanning electron microscopic study using corrosion casts in the rat. J Pefiodontol, 1994,65:1079 - 1087.
10Berkovitz BKB. The structure of the periodontal ligament: an update. Eur J Orthod, 1990,12:51 -76.
