Your unit light is kept at arms length above or in front of the patient. The light should be easy to reach but not near the patient's or operator's head. Illumination of the treatment area becomes more difficult when the light is positioned too close to the patient. In addition the light generates a large amount of heat. Direct the unit light from above the patient as shown in figure 3-3.

The position of the bracket table should be low enough to permit a clear view of the instruments. It should also be a reasonable distance above and to the side of the patient.

The patient's open mouth should be level with your waist. This will enable you to reach the patient's mouth while maintaining your arms at waist level. For mandibular instrumentation, the patient will have his or her mouth open in a chin-down position. Position your legs under the back of the chair. The back of the dental chair should touch the top of your legs, or you may straddle the back of the chair with your legs.

Now you are ready to learn how to position yourself around your patient in relation to the treatment areas of the mouth. Operating positions for right-handed and left-handed technicians are usually identified in relation to a 12-hour clock (figs. 3-4 and 3-5).

Figure 3-4. - Operating positions-right-handed operator.

As you try various positions, notice how they afford you a clear view of the treatment area. You will not be able to obtain a clear view of the teeth surfaces in the mouth through operator and patient positioning

Figure 3-3. - Unit light placement.