Clinical evidence and Science 15 Internal gap / abutment angulation Rotational freedom (α/2) 0.7 deg 0.95 deg 1.5 deg 1.65 deg 1.85 deg 5 µm assumed internal precision 0 deg 17 µm 40 µm 183 µm 203 µm 266 µm 5 deg 187 µm 316 µm 578 µm 633 µm 782 µm 10 deg 401 µm 597 µm 1.03 mm 1.17 mm 1.31 mm 15 deg 597 µm 868 µm 1.47 mm 1.66 mm 1.87 mm 20 deg 796 µm 1.11 mm 1.82 mm 2.05 mm 2.33 mm 60 µm assumed internal precision 0 deg 18 µm 23 µm 33 µm 43 µm 45 µm 5 deg 18 µm 23 µm 33 µm 43 µm 45 µm 10 deg 18 µm 23 µm 33 µm 43 µm 45 µm 15 deg 18 µm 23 µm 33 µm 89 µm 316 µm 20 deg 18 µm 23 µm 33 µm 576 µm 802 µm 100 µm assumed internal precision 0 deg 19 µm 25 µm 37 µm 44 µm 50 µm 5 deg 19 µm 25 µm 37 µm 44 µm 50 µm 10 deg 19 µm 25 µm 37 µm 44 µm 50 µm 15 deg 19 µm 25 µm 37 µm 44 µm 50 µm 20 deg 19 µm 25 µm 37 µm 44 µm 162 µm Tab. 1_The size of the marginal fit gap of the superstructures depends on the degree of abutment angulation and rotational freedom ranging from 17 µm to 2.33 mm maximum when the internal precision of the superstructure was 5 µm. A range from 18 µm to 802 µm was observed with an internal precision of 60 µm, and from 19 µm to 162 µm with 100 µm. Based on this investigation the authors concluded that the rotation of the abutment is of clinical relevance because of its impact on the marginal fit of the prosthetic superstructure. (Adapted from Semper et al. 2010) Marginal fit of the superstructure at different assumed internal precisions simulated with different degrees of rotational freedom and abutment angulations SCIENCE BEHIND THE IMPLANT-ABUTMENT CONNECTIONS
RkJQdWJsaXNoZXIy MTE0MzMw