1. Dental Laboratory Instruments
Mr. Caputo
Unit #1 Lesson #9

2. Today’s Class
Driving Question: How are dental laboratory instruments used in a dental office?
Learning Intentions: We will be able to identify how to care for dental laboratory supplies and equipment.
Anchor: Explain why infection control should be practiced by all dental workers.

3. Equipment Requiring Heat Sources
Alcohol torches, butane torches, and Bunsen burners are used for smoothing wax surfaces, setting teeth, and heating wax-carving instruments
Important to periodically trim all irregular burned areas of alcohol torch wick and to check nozzle tip of alcohol and butane torches
Bunsen burner requires balanced air and gas mixture to produce clean blue flame

4. Vacuum Former
Used for rapid fabrication of custom trays, mouth guards, splints for temporary crowns, night guards for bruxism, and bleaching trays
Softens sheet of plastic with heat and then pulls it down onto the cast with suction
Trimmed model is placed on platform and heat is turned on
Heated plastic sheet hangs down over model approximately 1 to1 ½ inches, DA grabs handles of frame and pulls it down onto model, and then immediately turns on suction to draw hot plastic onto model

5. Vacuum Former
Courtesy Keystone Industries

6. Articulators
Designed to reproduce movements of mandibular arch in proper centric occlusion to maxillary arch
Dental casts made from patient’s impressions are mounted onto articulator with lab plaster
Various types are available
Facebow may be part of articulator

7. Facebows
Used to record relationship of maxillary arch to horizontal axis rotation of mandible
Rests on face and occlusal relationship is recorded by inserting wax, vinylpolysiloxane, or another material into oral cavity
Requires three points of reference
Earpiece facebow may be required

8. Articulator

9. Dental Lathe
Rotary machine used during grinding, finishing, and polishing procedures
Has extensions at both ends
Adapter or chuck is used to secure a wide variety of rotary instruments onto either extension
Instruments that can be attached to the lathe include acrylic burs, arbor bands, dental stones, and ragwheels

10. Dental Lathe
Flour of pumice may be used in conjunction with dental lathe
All brushes, ragwheels, and other laboratory tools should be used only for one patient and sterilized between patients to prevent cross-contamination
Pumice solution used at polishing lathe should be dispensed following unit dose concept

11. Mixing Bowls Made of flexible rubber or plastic material
Used to mix alginate impression and gypsum materials
Small, medium, large, and extra-large sizes
Spatula is used to blend powdered alginate or gypsum and water together in the bowl
Should be disinfected by spraying with disinfectant and wiped dry for storage
Disposable bowl liners and wooden spatulas may also be used

12. Vibrators
Used to move dental plaster or stone gypsum products when pouring a cast model
Impression is placed on flat-top working surface of vibrator as gypsum material is poured into it
Vibrator increases density of mix by eliminating air bubbles
Control knob is used to adjust intensity of vibration
Rubber platform should be kept covered with plastic cover and damp paper towels

13. Vibrator

14. Model Trimmer Used to trim and contour gypsum cast models
Electrically operated machine that has round abrasive wheel, short working table, and water-dispensing mechanism
Wheel rotates while water flows onto it, keeping it clean
When finished, allow the water to run for one full minute to flush out particles from trimmer drain to prevent clogging of gypsum material in plumbing lines
When operating, fingers should be kept away from wheel and safety glasses or goggles should be worn

15. Model Trimmer

16. Common Instruments Used in the Dental Laboratory
Lab spatulas with narrow or broad flexible blades
Wax spatulas made of metal
Lab knives

17. Homework #4
Explain how you would train a dental worker in infection control.