The analysis is done to the mechanism of the less damage of the pricker roller. Conclusion is made that the tooth width of the wire may be the cause of the more damage of the wire roller.

Analysis shows that the distribution of meshing points is a function of the axial circular pitch, the axial space of two meshing points on a tooth and the effective width of the gear.

Conclusion (1) Insufficient basal bone width and excessive tooth size were the main causes of tooth crowding and tooth removing treatment.