Ivoclar Vivadent PS Empress CAD Chairside - Manual (Page 10)

10
Preparation guidelines and minimum thicknesses
Successful results can only be achieved with IPS Empress CAD if the preparation guidelines and layer thicknesses are strictly
observed. The following minimum thicknesses are required for IPS Empress CAD restorations.
Inlays and onlays
It is absolutely necessary that you take the static and dynamic antagonist contacts into consideration. Do not locate the
preparation margins on centric antagonist contacts.
Observe a preparation depth of at least 1.5 mm and an isthmus width of at least 1.5 mm in the fissure area. Prepare the
proximal box with slightly diverging walls and observe an angle of 100–120° between the proximal cavity walls and the
prospective proximal inlay surfaces. For inlays with pronounced convex cavity walls without adequate support by the
proximal shoulder, avoid marginal ridge contacts. Round out internal edges in order to prevent stress concentration within
the ceramic material. Eliminate the proximal contacts on all sides. Do not prepare slice-cuts or feather edges.
Observe at least 2 mm of space in the cusp areas. Ensure that the shoulder does not show any inclinations, i.e. it must
show a 90° angle to the residual tooth structure. Onlays are indicated if the preparation margin is less than approximately
0.5 mm away from the cusp tip, or if the enamel is severely undermined.
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0
2.0
> 0.6
> 0.7
>1.0
>1.0
1.5 1.5
>1.0
1.5
2.0 2.0
1.5
>1.0 >1.0
1.5
>1.5
4°
100-120°
>1.5 >1 5 >1.5
>1.5
>2.0
90°
>1.5
4°
>1.5
> 0.6
>0.7
>0.7
1.0