Years ago while doing some research for a program on posterior composites I came across interesting information about how interproximal wedges work. The article looked at the distance the teeth were separated over the time the wedge was in place. What caught my eye was that the effect of the wedge increased for the first few minutes it was in place. I immediately incorporated the concept of pre-wedging while doing posterior composites. As soon as the anesthesia has taken effect I place the largest wedge I can in the interproximal between any teeth where I will be preparing the interproxmal.
Since than with the routine use of sectional matrix systems and the effectiveness of the ring separators the concept of pre-wedging has fallen out of favor and when I discuss it in a lecture I get asked why I still follow this protocol. This week I decided to answer that question for myself and on Tuesday treated two patients, both scheduled for posterior composites, without pre-wedging. Wednesday morning I came in to the office more committed then ever to always placing the wedge as the first step in class two and three restorations.
What I learned was invaluable and I can now clearly answer why I follow this protocol. The first reason that pre-wedging the teeth is incredible valuable is by the time I am preparing the interproximal box a very slight space has opened between the teeth. This space allows me to prepare the box without the worry of accidentally nicking the adjacent tooth. I know that some people actually place the sectional matrix as an added reassurance of not damaging the adjacent tooth, but I found just the space from the wedge does the trick.
The second and maybe more important reason is that when the wedge is placed first it compresses the interdental papilla. As I prepare the floor of the interproximal box and create clearance I am looking at and sometimes cutting the wedge, not the tissue. I hadn’t realized before this week how difficult it is to manage the tissue, not cause some amount of bleeding, and then keep the tooth isolated during bonding without pre-wedging.
Lastly, I do believe that placing the wedge first, increases the space between the teeth, allowing for an even better interproximal contact then simply placing the wedge and ring separator after the prep is complete. So, once again I am a raving fan and have already gone back to my standard protocol of picking up a wedge wand and placing it interproximally prior to picking up the handpiece.