Figure 3-13. - Air polishing unit.
orthodontic bands and brackets are applied. Air polishing of enamel also increases resin bond strength when used before acid etching for sealants and other procedures.
Components The three major components of the unit are the air polishing delivery system, foot-controlled switch, and handpiece assembly. Some newer models combine the air polishing and ultrasonic systems. In such units, additional components and controls exist because the units are combined (fig. 3-14). The combination handpiece assembly has separate openings to accommodate the scaling and polishing inserts (fig. 3-15). The operation and maintenance of the combined unit are the same as the two independent units.
Technique Keep the handpiece tip approximately 4mm to 5mm from the tooth surface being cleaned. Center the spray on the middle one-third of the tooth and use a constant circular motion. The edge of the spray will
Figure 3-14. - Combined ultrasonic scaler and air polishing unit.
Figure 3-15. - Handpiece assembly of an air polishing unit.
clean the tooth surface near the gingiva. The angulation of the handpiece tip to the surface varies according to the different locations of the teeth.
On the facial and lingual surfaces of all posterior teeth, direct the handpiece slightly distally at an 80° angle toward the gingiva (fig. 3-16). On the facial and lingual surfaces of all anterior teeth, direct the handpiece at a 60° angle toward the gingiva (fig. 3-16). For all occlusal surfaces, direct the handpiece at a 90° angle to the surface.
Precautions and Contraindications You must be concerned with several precautions and contraindications to the use of the air polishing system. Avoid direct contact of the cleaning jet with soft tissue. This could seriously and unnecessarily harm mucosa or gingiva. To preclude possible soft tissue emphysema or air embolism effects, never direct the tip into the sulcus. Sodium bicarbonate air polishing of highly polished metal restorations will leave a matte (dull) finish. Avoid prolonged use of this system on cementum or dentin. Consult with a dentist
Figure 3-16. - Angulation of the air polishing handpiece tip on facial and lingual surfaces of anterior and posterior teeth.Continue Reading