Tips and tricks: parameters (part II)
In the June edition of CEREC News we started with the explanation of the parameters for the CEREC 3D software V3.10. Part I gave an overview of the parameters, described the purpose which they serve, and explained what dimensions of the restoration they influence. If you didn’t read Part I in the June edition CEREC News, now is a good time to do so.
In this edition of CEREC News we will take a closer look at the following parameters: proximal contact strength, occlusal contact strength, occlusal offset, margin thickness, and veneer thickness.
Proximal contact strength
Initial value: 0; minimum value: -200; maximum value: 200; effect on: restoration proposal; works on: inlays/onlays and crowns.
The CEREC 3D software automatically determines the proximal contact strength. This step is performed before the proximal contact line is displayed. You thus have the possibility of evaluating the result and modifying it, if necessary.
Let’s say you find that the contacts proposed by the software are generally too strong or too weak. You can change them according to your wishes in the “Settings”/”Parameters…” menu.
If you increase the value of the "Proximal contact strength", correspondingly more material will be applied to the contact points. This is indicated by the red colour in the lower right image.
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The thickness of the contact points can be adjusted in increments of 25μm between -200μm and 200μm.
Tip: If the neighbouring tooth is located at a distance of more than 1 mm (e.g. neighbouring tooth is prepared), no contact is made.
Occlusal contact strength
Initial value: 0; minimum value: -200; maximum value: 200; effect on: restoration proposal; works on: inlays/onlays and crowns.
With this parameter you can set the contact strength for crown restorations to be produced in connection with the “Virtual grinding” setting. Virtual grinding can be found under: Settings -> Configuration -> Options -> Virtual grinding.
The virtual grinding strength is the contact strength of the restoration with the antagonist tooth.
Inlays/onlays in combination with “Virtual grinding” can be activated via the “Antagonist” dialogue box:
The strength of the contact points can be adjusted in increments of 25μm between -200μm and 200μm.
Occlusal offset
Initial value: 0; minimum value: -500; maximum value: 500; effect on: milling result; works on: inlays/onlays, crowns and veneers.
Ceramic material is added or removed from the occlusal surface (‘Z’ offset).
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If you find that all of your restorations have too little or too much material in the occlusal direction, you can compensate for this with this parameter.
The occlusal offset can be adjusted in increments of 25μm between -500μm and 500μm.
Tips:
- This setting affects the restoration only during the milling process. The effect is not visible in the milling preview.
- If the occlusal surface is in non-occlusion in the design mode “Correlation”, try increasing occlusal offset.
- Caution:Extreme values can cause changes in the proximal contacts.
Margin thickness
Initial value: 0; minimum value: 0; maximum value: 200; effect on: milling preview and result; Works on: inlays/onlays and crowns.
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Prior to the milling of inlays, the “Margin thickness” setting can be adjusted.
The two images below show margin thickness in relation to crowns.
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The margin thickness can be adjusted in increments of 25 μm from 0 μm to 200 μm.
Tips:
- Increase margin thickness to prevent chipping of the ceramic material during the milling process;
- Increase margin thickness for easier polishing of the margin.
Veneer Thickness
Initial value: 500; minimum value: 0; maximum value: 2000; Effect on: initial proposal; works on: veneers.
This parameter allows you to set the initial veneer thickness for veneer restorations using the following design techniques: Dental database and Replication.
The “Veneer thickness” can be adjusted in increments of 100 μm from 0 μm to 2000 μm.
Tip: Apply more material if you wish to perform individualization, staining and glazing.
In the next issue of CEREC News we will discuss in detail the “Spacer” and “Adhesive gap” parameters. Furthermore, we will look at one of the most frequently discussed topics: “What is the difference between the spacer and the adhesive gap?” Till next time have fun with your CEREC system
