Procera Cerec Everest Lava Celay Wol-Ceram Epc-CAM Cercon etc.
Application of science to dentistry CAD/CAM made it possible to work with a new generation of hard ceramics in dentistry. These materials cannot be cast so therefore must be machined. In order to machine something a cutting path is required. The cutting path is generated from digital scanned data.
SCAN THE OBJECT
CREATE DIGITAL DATA POINTS
GENERATE CUTTING PATH
MACHINE REPLICA OBJECT
CAD/CAM What is dental CAD/CAM? Dental CAD/CAM is the process by which the model of a prepared tooth is scanned. This data is then used to generate the coping design (CAD) which in turn is used to generate a cutting path for manufacturing the coping (CAM).
Computer Aided Design (CAD) and Computer Aided Manufacture (CAM) in restorative dentistry can be used to: Reduce production time for copings and frameworks; increasing overall productivity Introduce consistent and measurable accuracy Provide evidence of product quality
CAD/CAM technology
Scanner - digital impression of the prepared teeth Software – CAD - digital cast on the screen - virtual design of the model Milling unit – CAM - computer aided milling unit (cnc) - grinding process
Non-contact sensor: optical: laser point, laser stripe, white light, fotogrammetry
Contact sensor: mechanical
Elements – material versatility
Presintered, yttrium-stabilised, HIP zircon Copings and bridges
Non- shrinkage zircon silicat Full crowns in the posterior region Industrial manufactured titanium blanks Copings, crowns and bridges Leucite-reinforced glass ceramics Inlays, Onlays, Veneers as well as anterior and posterior copings
Green processing Milling
of presintered ceramic blocks advantage: easy to process, grinding instruments do not have to be replaced that often disadvantage: porous presintered zirconia shape shrinks during final sintering- enlarged substructures= software calculated
Hard processing Milling
of dense sintered ceramic blocks Takes more time, grinding instruments wear off
HIP= Hot Isostatic Press : special sintering technique High
temperature and pressure applied to densify the material, gaining 20% more in strength
Frameworks zirconium oxide
CAD/CAM methods
In clinic - the dentist purchases an intra-oral scanner, the cutting machine and the consumable materials. All the work is done by the dentist at the clinic. Mainly suitable for full crowns, inlays and onlays.
In lab - the laboratory purchases a scanner, cutting machine and consumables. The dentist sends the patient's impressions and prescription to the lab. The lab scans models of the prepared teeth, designs the restoration and machines the restoration.
CAD/CAM methods
Centralised machining - in this situation the lab purchases or leases a scanner only. Again, the dentist sends the patient's impressions and prescription to the lab. The lab scans models of the prepared teeth and designs the coping and then sends this data off to an external machining centre. The machined coping is returned to the lab for veneerig.
Centralised scanners and machining - the laboratory sends the model away to the external centre to be scanned. The coping is also designed and machined at the external centre. The model and coping are sent back to the lab for veneering.
ProceraCentralised machining
Stockholm/ Sweeden
Making a sectioned cast in the lab Scanning the die and the cast CAD-data sent to central machining center (checking) Milling starts in 19 minutes Copings (hand) packed and mailed delivered within 5 days First patient 1985 (1994)
Katana-Centralised machining
Semmelweis Laboratory
Everest-in lab •
ScanMeasuring unit
• EngineMilling and grinding unit •
ThermSintering unit
•
ElementsMaterials
Software User interface
Light beam projection
15 projection sequences
The rotary plate moves on its vertical and horizontal axis during this process
CAD- Software
The preparation limit is automatically detected
Design Decision guidance
Form of margins Juncture region Metal margin Framework thickness
3-D virtual view of the occlusion on the screen The distances between occlusion and framework construcion are shown with different colours. Easy, quick and safe design of frameworks in connection with the virtual wax knife.
Design Virtual wax knife -
-
Can be used to process the virtual framrwork in three dimensions on the screen Precise addition or removal of virtual material enables quick and precise waxing
Design
Cantilever bridge
Bridge for veneering
CAM Engine
5-axis technology Ensures secure milling of undercuts • The wide degree of freedom during the milling process enables complex geometry • Engine speed 5.000 – 80.000 min-1
Engine Simultaneously controlled 5-axis technology Thin crown margins and best marginal fit The wide degree of freedom during the milling process enables complex geometry Engine speed 5.000 – 80.000 min-1
Engine
The 5-axis milling strategy
5-axis technology
Milling of titanium
Cerec-in clinic
Intraoral scanning-no impression Digaital images of tooth and opposing arch