rad_doc said:
Hi Ivorine dust,
I got rubber pot holder which is 1.2mm like what u suggested.
I marked it with the marker and held the marked side towards me and let my typho bite it. After reduction itried to check it (c plane in#3). I didnt see any marks so i thought reduction is done.I took it out and checked it handheld but my reduction is nt complete.
I really appreciate if u could tell me how u checked it and where exactly u see
the marks.
rad_doc:
Use a water based felt tip pen. Do not use a Sharpie. The marked side faces the occlusal your prep. It also helps to cut the material a little less than the M-D dimension of the tooth you are prepping. You can taper it it bit if you like. Then insert the guide from the buccal.
Marking the functional cusp bevel on #3 is tricky, but it will make a mark if your reduction is less than 1.2. Be sure to insert the guide all the way past the palatal side of the tooth, and check that it does not touch the occlusals of the adjacent unprepared teeth. This is why you want to cut it narrower than the M-D of your prep.
Also make sure that the rest of the teeth appear to be in occlusion as you close the typodont. That means you might have to close the typodont harder. I sometimes do a "tap-tap-tap" while moving the guide a bit, just to make sure the prep contacts the inked surface. If it doesn't mark, you should have 1.2 mm clearance. If it marks only on the cusp tip and ridges, do not reduce it right away. It could be a false registration. I reduce only the marked slopes and very minimally on the cusp ridges and tips.
I would prefer to use this method since it won't be as time consuming as blu-mousse--you'd know how you are doing with your reduction in an instant. That is pretty convenient if you have to check and recheck it a few times during the exam. Although blu mousse is more reliable, it involves a couple of minutes waiting time, and then you have to slice it sagitally or whatever, then measure with a perio probe or RGS. It also involves a few more things which can clutter your work area. And the best part-- the pot holder only costs a dollar
Making a putty stint before prepping as Bansu suggested is an excellent method and, I would use it as an adjunct to verifiy what is registered on my clearance guage. This is because "reduction" and "clearance" are two different things. For example, if you reduced a surface by 1.5mm, but before prepping there was already an existing clearance of about. 0.7(as in the case of occluso-distals of #19 or #30 ) you would have over reduced that portion of the tooth already. Check any typodont, even the equilibrated ones, and you are likely to find existing clearances on the distal between #14 and #19 and #3 and #30. If you use a clearance guide, then you would not reduce that more than necessary.
Guys, I'm sorry if I sound like a "know-it-all", but I have been "immersing" myself for the last three years with this exam like my life depended on it
😳 Like you, I've invested countless hours and thousands of dollars on it. Having very little to spend, I look for ways to make this struggle easier.
Hope this helps, rad_doc. PM me if you need more.
Bansu, thanks for the update! I look forward to seeing that RT Exam handbook in the DBC website. With regard to measurements, I heard that the Board would like to see more reduction. How true?
Ivorinedust.
"Apolonia, relieve my toothache!"
