Minutes of meeting  March 7, 2002
Submitted by George F. Green, D.D.S.
 

Introduction - Dr. Gantes and Dr. Yamada

Please remember to sign the sign-in sheet, and complete an evaluation. These items are needed for Continuing Education credentialling.

CHANGES IN 2002 STUDY CLUB PROGRAM !!!
1. Meeting scheduled for Thursday June 6 HAS BEEN CHANGED to Wednesday June 5, 6:00PM Long Beach
    Yacht Club
2. Meeting scheduled for Thursday October 3 HAS BEEN CHANGED to Thursday December 12, 3:00PM -
    9:00PM  Marriot Hotel, Long Beach Airport

Visions in Prosthetics In The New Millennium - Dr. Momo Vasilac
Dr. Vasilac has worked in Sweeden with Dr. Branemark, and has been with Nobelbiocare company internationally for the past eight years. A sophisticated animated computerized slide presentation with digitized film clips accompanied Dr. Vasilac's presentation.

A. The following are HERE NOW:
1. Scanning - capture/gather accurate data - most important step
    1. high-performance camera
    2. Procera machine (laser/probe): CAD-CAM manufacturing
    3. "copycat machine" - DeGussa, creates with cubic zirconia, difficult to mill at 30-40 micron accurately
    4. structured light patterns (used currently in auto industry)
    5. rainbow camera (numerization)
    6. Zirconia paste (KaVo-Everest) may decrease cost of production - inexpensive material to work with
    7. laser scanner (Cerac)
    8. laser scanner (GN-I) milling of finished block
   All these methods are variations in collection of data
    Scanning methods: laser, structured light, Photogrammetry (Jemt), Digital Surface Photogrammetry
   All these techniques require humans to run and maintain the machines
2. Process data  (dependent upon quality of software)
    1. Procera 3-D software (interface)
    2. high/low data density: less crucial areas in process use lower density data to minimize computer file size
3. Production technology (infiltration, sintering, rapid prototyping)
    1. casting - change crystal structure of metal by melting
    2. milling - difficult to control at 20-30 microns, induces stress in material
    3. sintering - less material stress than milling
    4. titration (infiltration) - mixing, compacting, sintering - not new in manufacturing industry/new in dentistry
        particles compressed and condensed without melting
4. Development of new materials (nanoparticles)
   1. Nanotechnology - wet / dry - smaller particles allow greater compaction: enhanced physical properties.
        Can be used in genetics - can manufacture at DNA level; computer chips can be miniaturized to the point of
        true interactive capability

B. New In 2002:
Procera process:  computer-controlled, compensates for shrinkage in sintering process
"Procera goes 3-D"
    1. 0.4mm coping - great strenght / less tooth reduction
    2. 0.4mm clear coping
    3. New formula zirconia - improved esthetics over "old" zirconia copings
    4. Procera all-ceramic bridge
    5. New veneer material
Fixture devlopments:
    1. personalized prosthetics
    2. implant bridge / "All-In-One"/ Procera Implant Bridge (latest "correct" terminology)
        Local lab does wax up
        Models are laser-scanned, data transferred to Procera via modem
        Procera returns one-piece framework to local lab
        Local lab applies porcelain
     Current manufacturing focus is on production of coping . . . no focus yet on veneering material
     CT scan = best source for obtaining accurate data
    Accuracy of laser for data acquistion is limited - depends on light absorption
     In  tooth preparation, avoid "J" shaped margins - Procera scanner probe cannot "read"/duplicate
    Avoid feather-edge margins: veneering porcelain is needed for esthetics - need adequate reduction, use
    modified shoulder. 2mm occlusal reduction is recommended.
    Procera is a manufacturing process . . . it is not a dental lab. No humans touch the coping product during the
    manufacture.

C. What Is Coming In The Future?
Powder metalurgy (PM) - smaller particle size. American society is most likely market for new products of new technology. Basic concept: "Photo" is taken (image capture), machine then creates "part" from "nothing" - actually by layering technique.
Production Technology
    1. 3-D printing
    2. Stereolithography
    3. Selective laser sintering
    4. Fured deposition modeling
    5. Laminated object manufacturing
    6. Direct photo shaping
    7. Multi-jet modeling
    8. Solid ground curing
   9. Rapid prototyping

Meeting adjourned at 9:30 PM