Ivoclar Vivadent IPS e.max Clinical Guide - Manual (Page 15)

15
3-unit bridge
The preparation of the abutment teeth is the same as for anterior and posterior crowns.
Note regarding lithium disilicate glass-ceramic (LS
2
) bridges:
Given the different masticatory forces, the maximum acceptable pontic width is different in the anterior and
posterior region.
The pontic width is determined on the unprepared tooth.
– In the anterior region (up to the canine), the pontic width should not exceed 11.0 mm.
– In the premolar region (canine up to the second premolar), the pontic width should not exceed 9.0 mm.
Maximum
pontic width
9 mm
Premolar area
up to the canine
Maximum
pontic width
11 mm
Anterior region
Bridge
(4– and multi-unit bridges)
− Evenly reduce the anatomical shape while observing the stipulated minimum thicknesses.
– Prepare a circular shoulder with rounded inner edges or a chamfer at an angle of approximately
10 to 30 degrees.
− Ensure that the width of the circular shoulder/chamfer is at least 1.0 mm.
− Reduce the incisal or occlusal crown third by at least 2.0 mm.
− Reduce the vestibular and/or oral area by at least 1.5 mm.
Practical procedure for restorations with IPS e.max | Preparation
1.0
1.5
1.0
1.5
2.0
1.0
1.5
2.0
1.0 1.0
1.5
2.0
1.5
6°
ZrO
2
LS
2
ZrO
2