Lec 1/26 Cad/Cam 1 Flashcards
Types of CAD/CAM deposition:
Fused deposition (fuse small particles in a large pile to make object), seletcive laser sintering method (build up selectively on only the object), stereolithography (object raises out of pool of monomers)
5 axis modeling can rotate how many degrees around hor?
30’ in either direction
Triad of fabrication for CAD/CAM
scanner, resto desing software, resto fabrication/ production
Man and year he 1st started CAD/CAM development:
Dr. Duret, ‘71
1st stage of CAD/CAM development:
optical impression of abutment tooth, then design optimal crown, mill crown using numerically controlled milling machine
Developer of CEREC:
Dr. Moermann
Adv of the CEREC system:
chairside, directly measure prep intraorally, designa nd carve inlay from a cermainblock, compact machine, same day restos
Function of scanner:
transforms geometry of receptor unit (tooth/implant) into digital data that can be processed by a computer
Types of scanners:
optical, mechanical
Which scanner types can be non-chairside:
both optical and mechanical
Which scanner types can be chairside:
optical only
What type of scanner is the Procera?
mechanical
Mechanical scanner technique:
contact probe w ruby ball, maps entire cast prep surface line by line
Adv of mechanical scanner:
precise but less accurate than newer optical scanning system
Disadv’s to mechanical scaner:
time, expense, less accurate than newer optical scanning systems
Smallest intraolral scanner:
3M True definition scanner LAVA
Largest intraoral scanner:
Trios
Optical technologies, contact or non-contact?
non-contact
5 Non-contact optical technologies:
confocal microscopy, triangulation, optical coherence tomography, active wavefront sampling, accordion Fringe Interferometry (we skip)
Benefit of combining imaging techniques:
min noise
Technique for obtaining high resolution optical images w depth selectivity:
confocal imaging
Imaging technique good for 3D imaging:
confocal
What is confocal imaging:
light represents one pixel in resulting image, laser scans object, image obtained pixel-by-pixel and line-by-line, brightness = relative intensity of detected light
Mirror used in confocal imaging:
dichroic
types of confocal imaging:
parallel and spot
confocal imaging system used by iTero system:
parallel, red laser light beam
Adv of iTero system:
no need to coat pts teeth, no coating powders (TiO2)
Disadv of iTero system:
color wheel to the acquisition unit itself resulting in a camera w a larger scanner head
Can the lab make a crown using a physical model?
yes
Can you make a conventional resto using chairside milling?
no
STL lsf:
stereolithography
Disadv of STL:
describes only the surface of a 3D object wo color or texture
Adv of iTero/ STL:
open platform, can be sent to any milling unit