| 摘要 |
The invention relates to fixation plates for mandibular angle fractures, capable to ensure the reduction of the forces in the screws next to the fracture and to favour the formation of newly formed osseous substance while reducing the resorption risk. According to the invention, the plate consists of a flat body of a biocompatible material having a transverse symmetry axis (T) which divides the plate into two symmetrical mirroring halves, each half having two zones: a first zone (A, A') in the shape of a rectangular trapeze, where one of the non-parallel sides is the symmetry axis (T) corresponding to the trapeze height and, in the vicinity of the side opposing to the symmetry axis (T), there are the holes (G1 and G3) of the zone (A) and the holes (G2 and G4) of the zone (A'), having the shape of a rectangle rounded at the corners, so arranged that the major symmetry axes of the holes (G1 and G2) and of the holes (G3 and G4) are perpendicular to one another, the major symmetry axis of the holes (G1 and G2) being parallel to the trapeze bases and perpendicular to the symmetry axis (T), the symmetry centers (CS1 and CS2) of the holes (G1 and G2) being at a smaller distance to both the symmetry axis (T) and the small base of the trapeze, than the symmetry centers (CS3 and CS4) of the holes (G3 and G4), the large base of the trapeze exhibiting an approximately circular arch-shaped unevenness in front of the said holes, and a second zone (B, B'), in the extension of the first zone, on the part opposing to the symmetry axis (T), having an approximately circular shape and being provided with the holes (G5 and G6) in the zones (B and B', respectively), so that the centers (CS5 and CS6) of the holes (G5 and G6) approximately coincide with the center of the circular outline portion of the zone (B-B'), forming together with the centers (CS3 and CS4) an axis perpendicular to the symmetry axis (T). |
