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mechanical scalers markedly decrease anesthetic time and include both sonic and ultrasonic types. The most common type of mechanical scaler in veterinary dentistry today is the ultrasonic. They are very ef cient and have an additional bene t of creating an antibacterial effect
in the coolant spray (cavitation). Sonic scalers run on compressed air and are slower than ultrasonic scalers and do not offer cavitation.
The area of maximum vibration for ultrasonic scalers
is 1-2 mm from the tip. Do not use the very tip of the instrument as these are not effective for calculus removal and can potentially damage the tooth. The last 1-3 mm of the side of the instrument is placed on the tooth with a very light touch and kept in contact with tooth for up to 15 seconds. Once the instrument loses contact with the tooth, the instrument is no longer effective. The instrument should be kept in constant motion, running slowly over the tooth surface in overlapping wide sweeping motions to cover every mm2 of every tooth surface.
Supragingival hand scaling is performed with a scaler which is a triangular instrument with sharp cutting
edges and a sharp tip. Typically, the blade is at a 90 degree angle to the shaft, which is called a universal scaler. Scalers are designed for SUPRA-gingival use
only. The scalers (as well as curettes which are described below) are held with a modi ed pen grasp. The instrument is gently held at the gnarled or rubberized
end between the tips of the thumb and index  nger. The middle  nger is placed near the terminal end of the shaft and is used to feel for vibrations which signal residual calculus or diseased/rough tooth/root surface. Finally, the ring and pinkie  ngers are rested on a stable surface.
Hand instruments must be employed with a gentle touch. The instrument is held parallel to the tooth surface and the blade placed at the gingival margin. Hand scalers are used in a pull stroke fashion, which avoids lacerating the gingiva by pulling away from the soft tissue. The scaler is activated numerous times in overlapping strokes until the tooth feels smooth.
Step 3: Subgingival plaque and calculus scaling: This
is the most important step of the prophylaxis, as supragingival plaque control is insuf cient to treat periodontal disease. Unfortunately, this step is also the most dif cult, resulting in the increased incidence of residual calculus increases with increasing pocket depth.
Subgingival scaling is classically performed by hand with a curette, however, advances in sonic and ultrasonic tips now allow their use under the gingival margin. A curette has 2 cutting edges with a blunted toe and bottom. This design allows for effective cleaning without cutting through the delicate periodontal attachment
(as long as excess force is not applied). There are two types of curettes, universal and Gracey. Universal
An Urban Experience
curettes have a 90 degree angle and can therefore be used throughout the mouth. Gracey curettes are area speci c which means they are designed with different angles to provide superior adaptation to speci c areas of the dentition. Curettes are labeled by numbers which are used as follows: the lower the number (i.e. 1-2) the smaller the angle of the blade and the more rostral in the mouth the instrument is used.
Manual subgingival scaling is a very technically demanding procedure and although it will be brie y described here, the practitioner is directed to continuing education programs (such as San Diego Vet Dental Training Center ( to hone their skills. Subgingival scaling is performed as follows. Place the face of the curette  at against the surface of the tooth. Next, insert the instrument gently to the base
of the sulcus or pocket. Once there, the instrument is rotated so that the shaft is parallel to the long axis of
the tooth. Upon rotation and proper angulation, the instrument is in proper position to engage the calculus
as well as for root surface scaling and subgingival debridement. Finally, with the instrument in solid contact with the tooth, it is pulled from the pocket with a  rm, short stroke. This technique is repeated with numerous overlapping strokes until the root feels smooth.
Traditional ultrasonic scalers should not be used subgingivally to avoid thermal damage to the gingiva
and pulp. Thermal damage occurs if the water coolant cannot reach the tip of the instrument. Recently, sonic and ultrasonic scalers with specialized periodontal tips have been developed for subgingival use. Mechanical scalers are much easier to use appropriately than are curettes and thus are likely to provide a superior cleaning in the hands of novices. To accomplish subgingival scaling, these instruments are used in a similar fashion as supragingival scaling described above, however more care should be taken not to damage the root surface.
Step 4: Polishing: Polishing smoothes the surface of the teeth which retards plaque attachment. The polishing procedure is typically performed with a rubber prophy cup on a slow-speed hand-piece with a 90 degree angle. The hand-piece should be run at a slow speed, no greater than 3,000 RPM. It is important to use an adequate amount of polish is used at all times, as running the prophy cup dry is not only inef cient, it may also overheat the tooth. As with scaling, every mm2 of tooth surface should be polished. Slight pressure should be placed down onto the tooth to  are the edges of the prophy cup so as to polish the subgingival areas. One tooth may be polished for a maximum of  ve seconds
at a time, to avoid overheating. The tooth can be further polished after a short break.
Step 5: Periodontal probing, oral evaluation, and dental charting: This is a critically important step of a complete dental prophylaxis, and is unfortunately often poorly

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