SALIVA EJECTORS (MOUTHPIECE, SALIVA EJECTOR, DENTAL)
Saliva ejector mouthpieces are made to attach at one end to the saliva ejector
tubing on the dental unit. The other end rests in the mouth for the evacuation of saliva,
blood, water, or debris during dental procedures.
MOTOR DRIVEN ROTARY INSTRUMENTS USED FOR CAVITY
a. Burs (BUR, DENTAL EXCAVATING, SLOW-SPEED STRAIGHT
HANDPIECE OR SLOW-SPEED CONTRA-ANGLE HANDPIECE)
(1) Characteristics. In discussing the preparation of a cavity for restoration in
a modern clinic, it is essential that we talk about the many different kinds of burs available
to the dental officer. Regardless of the procedure being done, the burs will probably be
used in preparing the cavity for restoration. They are manufactured in different sizes and
shapes suited to the various types and forms of the cavity preparation desired. You will
be expected to know four different things about the burs that you are given: The shape
(name) of the working end, the series number of the bur, the material of which it is made,
and in which hand piece each type of bur may be used. Series numbers and bur shapes
are associated with each other: A round bur is in the ten series, an inverted cone bur is in
the thirty series, a straight crosscut fissure bur is in the five hundred series, and the
tapered fissure bur is in the seven hundred series. Burs may be made of one of two
materials: A stainless steel bur will have a smooth shank, and a tungsten carbide alloy,
bur will have a ring, a set of parallel rings, or possibly a ring of X's around the shank.
Tungsten carbide burs will stay sharp longer than stainless steel burs, and they may be
used repeatedly without marked reduction in cutting efficiency. There are three different
hand piece attachments for the burs. The slow-speed straight hand piece (SHP) uses a
friction grip attachment and accepts a bur with a long shank. This means that the end of
the bur that goes into the hand piece is smooth and is held in the hand piece by friction.
The shank of the straight hand piece bur is not only longer but also larger than the other
burs. The bur that goes into the slow-speed contra-angle hand piece (AHP) is almost as
large around as the straight handpiece bur, but it is much shorter and has a notched end
with a groove opposite the working end that fits into the latch attachment on the angle
handpiece. The bur for all high-speed hand pieces (HSHP) is smaller and shorter than
the other burs; it also has a friction grip attachment (that is, the end is smooth). The
Midwest Quiet-Air hand piece accepts the friction grip bur, but the hand piece is designed
with a chuck that must be tightened on the bur. Burs are an essential part of the setup for
the dental officer performing a restorative procedure. They are the rotary cutting
instruments that replace many of the hand instruments used in a cavity preparation
procedure. You will be required to know four identifying characteristics about dental burs.
(a) The first type is a description of the shape of the working end as
illustrated in figure 2-2.