| 摘要 |
The extraction forceps consist of two elongated lever arms joined at axis (3) as fronted by diverging arm head ends of which the upper arm head (1) is a round bent rod as against the head (2) of the bottom arm (2) formed from a semicircular bite-adapted plate placed on the teeth as support. An eared screw (5) is cemented in the drilled tooth root nerve canal or, the case of two roots, then a wire loop (6) or flexible spring steel ear (7) is anchored in the teeth and hung on the forceps top rod (1). Missing teeth and the tooth for extraction are replaced by hard rubber or plastics bodies (9) overlapping the jaws front and back to give the plate (4) firm support. In a longer-armed variant, the arm axis (3) is protended to both sides as bearing bolts, fitting the support plate with a protective plate on the angled rod of a handle. The forceps and the bolts either side are carried in this case between two support legs welded to the plate. Otherwise, the two components can be fixed together as assembled.
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