| 摘要 |
A new telescoping assembly or advancing sheath and an expansion complex are provided for a maxillary or mandibular arch expander. The advancing sheath (801) is provided with a spring (812) which extends between a forward end of the anterior tube (805) and a forward end of the posterior tube (803). The spring (812) urges the anterior tube (805) rearwardly relative to the posterior tube (803) to compensate for jaw pressure and to help prevent the jaw pressure from threading the anterior tube (805) rearwardly. The expansion complex includes an outer housing and an advancing member which is telescopically received in the outer housing. The two portions of the expansion complex are received in opposed halves of a plate which fits against the mandibular or maxillary arch. An threaded rod and a parallel post extend through the housing. An activation nut is received on the threaded rod, and an activation plate is journaled about both the rod and the post. The activation plate is moved by movement of the activation nut. A spring is journaled about the post between the forward end of the advancing member and the activation plate. The nut is accessible through a channel in the top surface of the housing and advancing member.
|
