| 摘要 |
Injection needle devices for administering a local anesthetic into tough, dense ligamentary tissue surrounding a tooth. The injection needle is a two-part needle that includes a proximal needle portion formed of metal, ceramic or rigid plastic and a distal needle portion formed of ceramic or hardened metal. The distal penetrating needle portion has an exposed length not more than about 8 mm, and an maximum outside diameter of about 25 gauge. At the transition between the proximal needle portion and the distal needle portion there can be an abrupt stop surface for limiting penetration through tissue. Alternatively, the proximal needle portion can have a tapered surface that permits penetration of the tapered surface into tissue. The injection needle device is designed to minimize pain and prevent buckling of the distal needle portion. |
