Healing after experimental luxation and intraalveolar root fracture in immature rat teeth

In experimental group, root fracture occurred in four mesial roots out of eight teeth, and reparative dentin and cementum formed on the root fracture line over 3-4 weeks. On the periodontal side of the fracture, the surface of the dentin was covered with cementum, and partially covered with a large amount of cellular cementum. No distinct differences in root length were identified between the control group and the experimental group. All molars in the experimental group defined external root resorption. On the palatal area (cervical compression side), the depth and range of cervical external root resorption lacunae increased to 4 weeks. In experimental group, the width of periodontium tended to be larger than that in the control group, mesial tooth sockets had many blood vessels.