352H
Fig. 8.11 'Trough technique' of rubber
dam placement.8.6.4 Technique
Most texts on operative dentistry demonstrate techniques for the use of rubber dam. It
is not intended to duplicate this effort, but it would seem useful to point out features
of the technique that have made life easier for the authors when using rubber dam
with children.
Analgesia
Placement of rubber dam can be uncomfortable especially if a clamp is needed to
retain it. Even if a clamp is not required the sharp cut edge of the dam can cause mild
pain. Soft tissue analgesia can be obtained using infiltration in the buccal sulcus
followed by an interpapillary injection. This will usually give sufficient analgesia to
remove any discomfort from the dam. However, more profound analgesia may be
required for the particular operative procedure that has to be performed.
Method of application
There are at least four different methods of placing the dam, but most authorities
recommend a method whereby the clamp is first placed on the tooth, the dam
stretched over the clamp and then over the remaining teeth that are to be isolated.
Because of the risk of the patient swallowing or inhaling a dropped or broken clamp
before the dam is applied, it is imperative that the clamp be restrained with a piece of
floss tied or wrapped around the bow. This adds considerable inconvenience to the
technique and the authors favour a simpler method whereby the clamp, dam, and
frame are assembled together before application and taken to the tooth in one
movement. Because the clamp is always on the outside of the dam relative to the
patient there is no need to use floss to secure the clamp.
A 5-inch (about 12.5 cm) square of medium dam is stretched over an Ivory frame and
a single hole punched in the middle of the square. This hole is for the tooth on which
the clamp is going to be placed and further holes should be punched for any other
teeth that need to be isolated. A winged clamp is placed in the first hole and the whole
assembly carried to the tooth by the clamp forceps. The tooth that is going to be
clamped can be seen through the hole and the clamp applied to it. The dam is then
teased off the wings using either the fingers or a hand instrument. It can then be
carried forward over the other teeth with the interdental dam being 'knifed' through
the contact areas. It may need to be stabilized at the front using either floss, a small
piece of rubber dam, a 'Wedjet' (353HFigs. 8.6 and 354H8.11), or a wooden wedge.