A mouth mirror or dentist's mirror is an instrument used in dentistry. The head of the mirror is usually round, and the most common sizes used are the No. 4 and No. 5. A No. 2 is sometimes used when a smaller mirror is needed, such as when working on back teeth with a dental dam in place. The mouth mirror has a wide range of uses. Three of its most important functions are allowing indirect vision by the dentist, reflecting light onto desired surfaces, and retraction of soft tissues.

Indirect vision is needed in certain locations of the mouth where visibility is difficult or impossible. The posterior (or lingual) surfaces of the anterior maxillary teeth is a notable area where mouth mirrors are often used. Other areas of the mouth can be viewed more readily with the mouth mirror, even though it would be possible to see them if the dentist or dental hygienist adjusted their body into a poor position. Without the mouth mirror, poor body positioning would occur daily and lead to chronic postural problems, especially of the back and neck.

There are other areas of the mouth where lighting is difficult, even with overhead dentists' lights. In these instances, the mouth mirror is used to reflect light onto those surfaces. This is especially useful if the mirror is simultaneously being used for indirect vision of an obscure area.

Additionally, the mouth mirror is used to retract tissues, such as the tongue or cheeks, to gain better visualization of the teeth.

Dentist's mirrors are also commonly used by engineers to allow vision in tight spaces and around corners in equipment. They are a common tool in optics and laser labs as well.

It's one of the old realities of medicine that almost every procedure has some side effect. Dentistry is no different. In an effort to be safer by eliminating the use of silver amalgam fillings (which contained mercury, a poisonous metal), resin fillings were developed and used. However, the curing process for these filling can also be dangerous to a patient unless proper precautions are taken.

Resin Fillings

Resin composite fillings are made of a unique material that looks like the natural tooth, contains no mercury, and can easily be shaped to fit a cavity.

Function of Curing Light

Once the resin mixture is placed inside the patient's mouth it has to be cured, or hardened like ceramic. This means that a certain type of light must be shone onto the filling in order to harden it and bond it to the tooth.

Features

There are two main choices of light that will react with resin composite fillings, according to the American Dental Association. One is ultraviolet light, and the other is visible blue light. Both of these lights, while necessary to harden the fillings, can damage a patient's eyes.

Eye Danger

Of these two types, ultraviolet light is more dangerous to a person's eyes. It can result in macular degeneration, and has been linked to cancer. Blue light may also degenerate a person's eye--just not as quickly as ultraviolet light.

Prevention/Solution

In order to stop the light from reaching and damaging a patient's eyes, a protective shield should be placed around the light so that it may only go into the mouth and not reflect up into the patient's face.

A dental handpiece is a precision-built mechanical device designed for use with rotary instruments, such as burs, stones, wheels, and discs, used in dental treatment. Handpieces may be air driven, electric, or compressed  gas  (for  surgical  handpieces).  Surgical handpieces  are  discussed  in  Dental  Technician, Volume 2, Chapter 5, “Oral Surgery Assistance.” Handpieces can be classified according to the revolutions per minute (rpm) or speed at which they operate. One type is the low- or slow-speed, and the other is referred to as the high-speed contra-angle. Both the low- and high-speed handpieces use an air system to operate several parts of the handpiece. The main function of the air is to rotate the air turbine or vane drive. Basically, this means the air system is the main power source for these handpieces. Fiber   optic   accessories   attached   to   dental handpieces allow the provider to operate handpieces with a light source and is discussed in this section

As a dental assistant, it is your responsibility to care for and sterilize the dental equipment after each patient. Care must be taken in cleaning the dental handpieces because they are delicate and expensive pieces of equipment. By following the suggested procedure, you can ensure that your dental handpieces remain in good working order for several years.

? step 1

Remove the handpiece from the air/water line. Some handpieces simply pull off, and others need to be twisted. Remove the sharp burr and dispose it or prepare for sterilization.

? Step 2

Wipe the handpiece down well with a disposable germicidal wipe. Once you have removed any visible debris, discard the wipe. Wipe down again with a fresh wipe.

? Step 3

Place in the dental autoclave. When the autoclave is full, run as directed.

? Step 4

Put on clean gloves and remove the handpiece from the autoclave when the cycle is over. Run lubrication through the handpiece if it is scheduled to be lubricated. If you are lubricating the handpiece, run it on the air supply line to remove excess lubrication, and wipe with a germicidal wipe afterward.

? Step 5

Place the sterilized handpiece in a sterile envelope, and place on a tray or in a drawer for the next patient. When you are ready to use the handpiece, replace on the air/water supply line wearing clean gloves.