1 Surgery CAMLOG Compendium

4. Mechanics and
Biomechanics
Mechanical Tests
Finite element models were prepared
and the behaviors of different implantabutment
connections were compared
under vertical-lateral and torsional loading.
The simulation was conducted using
an FEM (finite element method) program
(ASNSYS 3.3) at Offenbach Technical
University.
Lateral Loading
The vector L of a load applied at 30° is
divided into an axial force (Fa) and a
lateral force (Fq). The axial component
and lateral force must be compensated
by the screw retention force as a function
of the length of the lever from the
fulcrum (D).
Finite element studies show that when a
vertical-lateral load is applied to the
abutment, the forces are transmitted
through the apical end of the tube to
the implant body. Loading of the abutment
screw hardly occurs.
Failure Load
Comparison of failure load (300 N at
30°) in a 3.75 mm screw implant with
an external hex connection clearly
shows that the CAMLOG ® abutment
screw is hardly stressed (blue = low
strain, red = high strain).
In the case of a force-based external hex
connection, the Fa is ~5 Fq because of
the lever ratio (the distance of the fulcrum
from the middle of the axis is the
implant radius).
Force-based connection
General System Information
Mechanics and Biomechanics
In the case of the form and force-based
CAMLOG connection, the lateral component
(Fq) is almost completely compensated
by the supporting forces (F1 and
F2) provided by the tube-in-tube connection.
Because of the configuration of the
tube-in-tube connection, the fulcrum
location is practically on the midline of
the implant. The lever length of the axial
force component (Fa) is thereby reduced
towards zero.
Form and force-based connection
External hex connection CAMLOG tube-in-tube connection
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