Class III prep - breaking the contact

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waxthrowaway123

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We are learning class III preps in pre-clinic right now, and we are being told that when prepping from the lingual we have to extend the prep gingivally enough to be able to see a crescent shape slightly on the facial side. I am not completely clear on what this means exactly or how to do this. Can anyone clarify?

Thank you.
 
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Yes, those are exactly what I am talking about! How do you correct a prep to give it that crescent shape if it is missing one? Are you actually removing tooth structure from the interproximal surface?
 
Yes, those are exactly what I am talking about! How do you correct a prep to give it that crescent shape if it is missing one? Are you actually removing tooth structure from the interproximal surface?
Keep removing tooth structure until you see it. I sometimes like to use the Jeffery 7 to keep removing tooth structure if it is a lingual access. You use a round bur in a slow speed.
 
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Keep removing tooth structure until you see it. I sometimes like to use the Jeffery 7 to keep removing tooth structure if it is a lingual access. You use a round bur in a slow speed.
Thank you! I think my instructor misspoke or I misheard. I talked to a few people and everyone was saying that you do have to remove tooth structure from the interproximal area to obtain the correct shape, not extend the prep gingivally. I appreciate all the great advice!
 
Thank you! I think my instructor misspoke or I misheard. I talked to a few people and everyone was saying that you do have to remove tooth structure from the interproximal area to obtain the correct shape, not extend the prep gingivally. I appreciate all the great advice!

Yes, you do remove tooth structure interproximally but you still need to maintain contact between the adjacent teeth even if its a slight contact
 
How do you guys bevel a class III (what do you use? and where exactly do you place the bevel?). I have been told different things but is only place on the C-shaped portion of the prep or is it present on the incisal and cervical parts of the prep, as well?
 
Gotta break ginigval contact. Don't break incsial. Dont extend prep past ridge.
 
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