Ivoclar Vivadent IPS Empress Esthetic Clinical - Manual (Page 8)

8
Preparation
Defect-oriented and minimally invasive
Preparation
Careful preparation is recommended for the durability and
accuracy of fit of the restoration. IPS Empress Esthetic is
adhesively cemented only. These instructions provide an
overview of the preparation requirements for indirect
restorations seated according to the adhesive technique.
For further information, we recommend consulting the
corresponding literature.
Basic rules:
– Complete a circular shoulder preparation with rounded
internal line angles or a chamfer; the width of the shoulder/
chamfer should be at least 1 mm
– Do not prepare feather edges
– Avoid sharp edges and angles to prevent stress and to
facilitate insertion
– The adhesive cementation procedure allows a defect-oriented
preparation
– Strictly observe the necessary minimum wall thickness to
ensure suitable stability of the restoration
Inlays
Take antagonist contacts into consideration.
Observe a preparation depth of at least 1.5 mm in the central fissure area. The isthmus
should be at least 1.5 mm wide. Complete the proximal box with a slightly diverging angle.
Round out internal angles to avoid stress concentration in the ceramic. Eliminate proximal
contacts. Do not prepare slice-cuts or feather edges.
Partial crowns
Follow the same procedure described for inlays.
Observe a preparation depth of at least 1.5 mm in the central fissure area and an isthmus
width of at least 1.5 mm. Provide 2 mm space in the area of the cusps and occlusal contacts.
Prepare the shoulder with an incline (10°-30°) to improve the aesthetic appearance of the
transitional area between ceramic material and tooth. Partial crowns are indicated if the
preparation margin is located less than approx. 0.5 mm away from the cusp tip, or if the
enamel is severely undermined.
Dimensions in mm
Dimensions in mm