Methods 38 patients with 43 young permanent incisors with complicated fracture were treated by partial crown-pulptomy or pulptomy randomly.

Objective: To explore the temporal change on the expression of GDNF and FGF-2 in spared dorsal root ganglia after partial dorsal root rhizotomy and acupuncture.

To establish dorsal root ganglion(DRG)resection model,in which the sensory nerve fibers were selectively degenerated while the motor nerve fibers remained intact and unaffected and to provide a effective method for quantitative evaluation of selective regeneration of peripheral nerve,20 SD rats were randomly divided into 2 groups,with 10 rats in each group.