laboratory. If you do not know these procedures,
patient cases can be lost or routed improperly. If you
have any questions about different procedures, ask the
dentist or prosthetic technician.
Cases entering the laboratory are required to be
accompanied with a work authorization request (DD
Form 2322). Requests are to be filled out with
instructions, signed by the requesting doctor, and must
indicate desired completion date. The case is then
entered into the Prosthetic Log and assigned a case
number. This entry must be made by the person
delivering the case to the laboratory.
Before entering the laboratory ALL impressions
are to be sprayed with an approved disinfectant in
accordance with BUMEDINST. 6610.10, chapter 6,
and covered with a plastic wrap (head rest covers work
great). The laboratory technician is to be informed of
the arrival of the impressions.
Alginate impressions are to be placed into the tray
holder at the plaster bench to prevent distortion of the
impression (a moist paper towel should be placed over
the impression to prevent dehydration of the material).
This includes complete dentures, removable
partial dentures, crowns, and bridges. These
impressions are poured as prescribed by the doctor; if
no instructions are provided, they will be poured with
stone mixed with liquid stone hardener.
Study casts are fabricated for diagnostic purposes
and poured as prescribed by the doctor. If no
instructions are provided, they will be poured in
STONE OR PLASTER CASTS
Trim the casts once they are separated from the
tray. Casts are trimmed to remove excess material by
use of the model trimmer.
You are required to don protective ear and
Turn on water supply to desired flow.
Activate the model trimmer.
Trimmed casts will be rinsed, dried, and marked
with the patient's last name and case number (if space
is available). The case will then be routed according to
the work authorization request.
CASES WHILE IN THE LABORATORY
Casts will be kept in case pans, protected in plastic
(when available). Case pans will be labeled with
patient's name, doctor, date started, and prothesis
Pumice and polishing procedures for the
fabrication of new protheses will not require special
precatutions. Repairs, relines, rebases, or adjustments
of any prosthesis that has had contact with patient's
body fluids are considered old cases and will require
precautions. Lathe instructions for pumice and
polishing are as follows:
The technician is required to ensure correct
placement of the protective shield is in the down
position before activating the lathe.
Pumice is to be replaced after each use.
Wheels/brushes used for pumice and polishing
are to be removed from machine and sent to
Prostheses should be put into a glass beaker or
ziplock bag containing cleaning solution, then
placed into ultrasonic.
The prosthetic ultrasonic cleaning machine is the
same as the CSRs except that dental prostheses are run
through. The following are guidelines for its use:
Ultrasonic to contain water approximately 1 to
1-1/2 inches. Special solutions to be used in
ziplock bags or glass beakers.
General-purpose cleaner or stone and plaster
remover solutions can be reused when used on
new cases. Once solution is used for an old case,
the solution is to be discarded.
Stain and tarter solution is used for old cases and
will be used one time then discarded.
Once the ultrasonic cleaning procedure is
completed, the prosthesis is then brushed and rinsed
with water. It is then bagged and replaced into the
assigned case pan.