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CAMLOG&Science – Chapter 2
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EFFECT OF CONNECTION DESIGN ON THE ACCURACY
OF REPOSITIONING
The theoretical calculations described above (Semper et al., 2009a; Semper
et al., 2009b and Semper et al., 2010a) were also tested in an experimental
in vitro study. Positional stability of five different implant systems (ITI, Steri-Oss,
CAMLOG
®
, Astra Tech, and Replace™Select) was compared after multiple
manual disassembly and reassembly (Semper et al., 2010b).
Five implants were arranged with varying angles in a stainless steel model
to simulate a typical clinical situation (Fig. 7). Abutments were assembled and
reassembled manually by three test persons for each implant system for 20
times by using system-specific screwdrivers. Any rotational, vertical, and
canting deviation from the initially determined position was monitored
using a coordinate reading machine. Rotational freedom ranged from 0.92
to 4.92 degrees. CAMLOG
®
showed significantly smaller rotational discre-
pancy than the other systems tested (Fig. 8A). The systems with a horizon-
tal butt-joint displayed significantly lower vertical alterations in position
than beveled implant-abutment connections (Fig. 8B). Regarding canting
discrepancies, the implant systems did not differ significantly (Fig. 8C). The
authors concluded that reposition of rotation-safe abutments on the
implants leads to a three-dimensional deviation compared to the initial
position and that the accuracy of repositioning is influenced by the geometric
design of the implant-abutment interface.
Fig. 7:
Occlusal view of the five tested implant connections
with their characteristic position indices: (A) ITI implant with
conical-joint and octagonal positional index, (B) Steri-Oss implant
with standard butt-joint and hexagonal positional index, (C)
CAMLOG
®
implant with butt-joint and cam positional index,
(D) Astra Tech implant with conical-joint and dodecagram
positional index, and (E) Replace™ Select implant with butt-
joint and polygonal positional index. (Semper et al. (2010b)
reproduced with kind permission of Quintessence Publishing co,
Inc, USA).