Operative dentistry aje qualtrough, jd satterthwaite la morrow, pa brunton

Other methods of moisture control
Saliva ejector
This may be used routinely during restorative procedures. The 
flange design is a useful protector and displacer of the tongue 
when the air turbine is used, it can also be used to reflect light. The
saliva ejector is generally held in position by the patient and is there-
fore dependent on co-operation. It is inadequate on its own, when
materials are placed in preparations, but may be supplemented by
any of the other moisture control techniques. Cotton wool rolls can be
used to stabilise the flange in situ and also serve to augment moisture
control.
Aspirator
This is a very efficient high volume, low vacuum suction device. It
needs continuous chairside assistance for effective operation and there-
fore cannot be used effectively in single-handed operative dentistry.
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Chapter 1
Fig. 1.11
Rubber dam clamps.
POOC01 02/18/2005 04:33PM Page 22

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Absorbent systems
Cotton wool rolls
These are essential supplements to the saliva ejector during place-
ment of both direct and indirect restorations. They act by absorption
and therefore have a limited service life and must be replaced 
frequently when saturated. The typical requirements for any poster-
ior tooth in a supine patient is three rolls; one in the upper buccal 
sulcus, one in the lower buccal sulcus and one in the lower lingual 
sulcus, in order to cope with salivary duct outflow and to collect 
pooling fluids. Cotton wool rolls are inserted with a rolling action
away from the alveolus for stability. In anterior teeth, two rolls 
are needed in the lower, one buccal and one lingual, while in the
upper a minimum of one roll in the upper buccal sulcus. It will 
be appreciated that rubber dam placement is a more efficient 
technique.
Cotton wool pellets
These are available in a range of sizes and are useful for drying pre-
parations and cleansing but they have the same limitation of service
life and cross infection risk as cotton wool rolls.
Absorbent plaques
These are sheets of absorbent material, which can be adapted to the
mucosa, and are arguably more stable than cotton rolls. They have
similar limitations of service life but are longer lasting due to the 
barrier effect.
It is important to note that all absorbents can produce painful after
effects, termed cotton burns, if they adhere to dry mucosa and are
then forcibly removed. Where such adherence occurs they should be
first soaked with water and then gently peeled off.
Air-jet
This is usually applied via an air–water syringe (3-in-1 or triple
syringe). It acts merely by forcibly displacing the fluid layer. If 
applied longer to achieve evaporation effect this technique can result
in desiccation of the dentine, which may be injurious to the under-
lying pulp.
Basic principles