Dental Handpieces

DLA 1203- Exam 3

1. Dental Handpieces Chapter 18*

2. Dental Handpieces Used for the following: Remove dental decay Prepare tooth for restoration Polish Polish and finish dental restorations Cut, finish, and polish dental appliances Trim models and trays

3. Parts of the Dental Handpiece Working end-where the burs, discs, stones, and other rotary instruments and attachments are held (chuck) The bur is placed in the chuck on the handpiece Head Shank- the handle portion Connection end-Forward and reverse controls may be located on the connection end The part of the handpiece that attaches to the power source

4. Dental Handpieces High-speed Low-speed Straight Nose cone Contra-angle Latch-type or friction grip Right angle or prophy angle Electric

5. High-Speed Handpiece Used to rapidly cut tooth structure and finish restorations Operate at up to 450,000 revolutions per minute (RPM) and higher A smooth, one-piece design, usually a contra-angle (attachment head) with the head slightly angled to the shank of the handpiece Does not hold any attachments Holds burs and other rotary instruments with the head of the handpiece in a small, metal cylinder called a chuck Holds burs with a friction-grip shank T o tighten or loosen the chuck, either a bur tooth/wrench or a button/release lever on the back of the head of the handpiece is used the manufacturer provides the specific tool used with the handpiece, so they are packaged TOGETHER

6. High-Speed Handpiece The power source for the dental handpiece comes from the dental unit Compressed air drives the turbines in the handpiece To activate and control the speed, a rheostat (foot control) is operated, (like the accelerator on a car) Available with fiber-optic light source Improves visibility of the tx area for operator The fiber-optic light is carried along optical bundles in the tubing of the handpiece

7. High-Speed handpiece High–speed handpieces can produce frictional heat, which can cause pulpal damage to the tooth. It is important to use a coolant, such as air, water, or and air-water spray to reduce the frictional heat.

8. High-Speed Handpiece with bur tool (chuck)

9. High-speed handpiece with push button back

10. Low-Speed Handpiece Low-speed handpieces are used in both the dental office and laboratory. Its uses in the dental office are to polish teeth and restorations, remove soft carious material, and define cavity margins and walls . Usually do not have water supply Operate at up to 30,000 RPM

11. Low-Speed A little bulkier than high-speed Used with long-shank (straight) rotary instruments, contra-angle attachments, and right-angle attachments

12. Low-Speed Handpiece Contra-angles are usually latch type Holds burs, discs, stones, rubber cups and brushes for intraoral and extraoral procedures Right-angles or prophy angles are used to polish the teeth with rubber cups or brushes Straight handpiece is used with long, straight shank rotary instruments Burs, discs and stones with attachment heads such as contra-angle and right angles.

13. Low-Speed Handpiece On the shank of the low-speed is a mechanism to lock the rotary instrument or the attachment onto the handpiece Could be a tightening knob, or snap-on apparatus Reverse and forward control is also found on the shank near the connecting end The power source for low-speed is the rheostat

14. Electric Handpiece Electric handpieces are an alternative to the air-driven handpiece. They are more versatile and used more commonly today, allowing for smoother cuts and refined margins with higher torque and precision . The electric handpieces are becoming more popular than the air-driven handpieces. The appeal of the electric handpiece is that it is quiet, vibration-free, efficient, and able to be sterilized.

15. Maintenance and Sterilization of Dental Handpieces Maintenance Follow manufacturer ’ s directions carefully

16. Guidelines General guidelines for maintenance and sterilization of a dental handpiece are as follows: While handpiece is still attached to the tubing and a bur, flush for 20 to 30 seconds. Remove debris by scrubbing the handpiece. Lubricate using the manufacturer’s suggested lubrication. Sterilize the handpiece. Lubricate if instructed.

17. Air Abrasion Unit and Microetcher Air abrasion Reduces use of anesthetics and drilling with dental handpieces Microetcher Smaller version of air abrasion unit used for intraoral sandblasting and dentin bonding Used for denture repairs, pit and fissure sealant preparation, and roughening the surface for bonding orthodontic bands When using the Microetcher, the dentist, assistant and patient should wear protective eyewear, and the dentist and assistant should wear a mask Both units require air pressure and an abrasive material. Abrasives used in the microetcher should be kept in a tightly sealed container to keep them dry and clean. It is important to consider safety for all involved while using a microetcher .

18. Microetcher, lab

19. Microetcher, intraoral