Denar Mark II - Operational Hand Grasps

10
Rear Wall Inclination
The posterior fossa wall of the Mark II
Articulator is nonadjustable but is con-
structed to average anatomic dimen-
sions. It is inclined posteriorly 25
degrees to allow for a backward move-
ment of the rotating condyle as it moves
outward (fig. 12).
HAND GRASPS
To use the articulator properly the oper-
ator must master the proper hand
grasps. A right handed operator curls
the fingers of the left hand under the
mandibular crossbar and places his left
thumb on top of the upper bow (fig. 13).
To effect both left and right lateral excur-
sive movements the left thumb guides
the back of the upper bow while the
forefinger and thumb of the right hand
holds the incisal pin moving it in the
desired direction. These hand grasps
can be best described as the underhand
push
__
pull grasps and the underhand
protrusive grasps. In order to execute
lateral movements the centric latch
must be open.
Underhand Push Grasps
To effect a right lateral mandibular
movement be sure the latch is open and
move the upper bow to the left. (The left
side of the articulator is the left side of
the instrument as it is viewed from the
rear.) Pressure is applied with the left
thumb to insure the left orbiting condyle
maintains contact with its superior and
medial fossa walls and the right rotating
condyle maintains contact with its supe-
rior and rear fossa walls (fig. 13).
fig. 11
fig. 12
fig. 13
Rear
Wall