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.
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 plaster.
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 eyewear.
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.
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 being fabricated.
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 CSR.
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. 8-34