#14 What I Learned Today

Introduction to Operative Dentistry

In sim lab, we learned how to isolate teeth using a rubber dam. Isolation is great (and necessary) for many reasons:

1. get improved vision by contrast of the coloured dam
2. allows for much easier access for tougher to reach posteriors
3. protects from airborne contamination
4. keeps the isolated area dry
5. blocks objects from being inhaled or ingested by accidental dropping
   
6. some patients may find it comforting as a direct barrier
   

The application is pretty basic: you punch holes in the rubber sheet with size and location corresponding to the tooth it is meant to surround, fasten it to the most posterior tooth with a clamp, lead the rest of the teeth through their holes, make sure the edges of the dam extends into the gingival sulcus, and finish off by placing a floss ligature between the last tooth isolated and attaching a metal frame.

Now for the specifics.

The hole puncher has a number of different sizes. I found the following to be effective for my rubber dam puncher:

• first (smallest) hole = do not use.
• second hole = mandibular incisors
• third hole = maxillary incisors
• fourth hole = canines and premolars
• fifth (second biggest) = molars
• sixth = do not use.
  

When practicing on a typodont, there are a number of things that you need to take into account to make life a little easier when placing the rubber dam. First, the typodont teeth are constructed to have very tight contacts. This makes slipping the dam better the interproximal spaces to be near impossible. Use your screwdriver to loosen up the screws on the back a bit, enough to allow the teeth to wobble. This will open up the contacts and make it much easier. As well, the typodont obviously is a very dry setting as compared to a patient's mouth. Lube it up a bit with whatever the school supplies. But note that some lubricants like Vaseline can actually react with the rubber and affect its properties, so be wary about what you use (must be water-soluble).

For the clamps, there are many different kinds and variations a dentist could use for different isolation situations and teeth, including winged clamps, non-winged clamps, and specialty clamps. The key is that the clamp is able to make four strong contact points with the tooth, and be stable (no wiggling or movement). We used these clamps for the following situations:

• #5 winged clamp: for molars on maxillary or mandibular
• 00 winged clamp: for premolars and canines
• W8A clamp: for maxillary molars
  
• 14 Clamp: for maxillary molars
• 212 Clamp: for anterior teeth
  

Some other important things to note, after you get the dam over the teeth, you should use floss to work the dam down into the gingival sulcus. Make sure that when removing the floss, you do so through the facial embrasure in order to not accidently remove the dam from the sulcus you just placed it in. As well, always tie a foot length of floss around the body of the clamp so that it can easily be retrieved in case it is dropped.