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Hey I’m just going to start my first corns preps tommorow,really excited!was wondering if you you guys can give me good tips on Burs I can use!
Thanks
Thanks
All ceramic Crown preps and provisonals
- Thread starter Anna.lario
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Most Important - Use a new bur, the more coarse the better. The fewer passes you do the better, the second most important rule is that the more you do, the worse it gets.
For Emax I like a nice thick chamfer, maybe 1-1.5mm, and ~2mm occlusal reduction. Zirconia you can do similar with less occlusal reduction. I keep all my posterior all ceramic preps above the gingiva or at worst at the level of the gingiva. Unless the caries has you go there, or you need more crown height, there is no real good reason to put a molar subgingival unless you're doing a PFM.
To make my occlusal reduction grooves, I take a nice new 330, sink it into the oclcusal, and draw lines through the central fossa, and up all of the cusps - take a football and join them all, boom, you've got a 1.5mm reduction.
Make sure you can read your margin 360. If you can't, the lab can't.
One of the most important rules for temps is that it's a temp. It's meant to be on for 2-3 weeks. In the anterior you need to make them pretty, in the posterior you do not, just functional. If you're using a light or dual cured acrylic like Integrity, a temp should take about 10-15 minutes to make tops. If you're taking more time than that, you're doing way too much! The way to ensure you have good contacts is to make the temp on the tooth, take it off, and put a pencil mark on the center of the interproximals. As long as you can still see pencil, you probably still have contact after you adjust.
If you have open margins, put the temp on the tooth, make sure there is saliva on the tooth, and put flowable composite straight on the open area and spread up to the body of the temp. Cure it, take it off, trim it up - boom closed margins. You can do this even if there is a massive hole on the tooth. I just had about 4mm of the lingual of one of my temps for a #9 break off, patched it up in two minutes, good as new, but don't go crazy if it's in a load bearing area.
Be sure you ask your patient if their bite feels "normal." Ask them if their opposite side feels like all of their teeth are coming together evenly. If not, keep adjusting those blue spots little by little until their natural teeth are all hitting "normally."
Lastly, there's something called a "Save your Ass" Bite - if you are prepping the most posterior tooth on a side, take the bite registration before you prep, otherwise their occlusion can change. Send that bite reg with the other impression.
Hope those help, good luck!
For Emax I like a nice thick chamfer, maybe 1-1.5mm, and ~2mm occlusal reduction. Zirconia you can do similar with less occlusal reduction. I keep all my posterior all ceramic preps above the gingiva or at worst at the level of the gingiva. Unless the caries has you go there, or you need more crown height, there is no real good reason to put a molar subgingival unless you're doing a PFM.
To make my occlusal reduction grooves, I take a nice new 330, sink it into the oclcusal, and draw lines through the central fossa, and up all of the cusps - take a football and join them all, boom, you've got a 1.5mm reduction.
Make sure you can read your margin 360. If you can't, the lab can't.
One of the most important rules for temps is that it's a temp. It's meant to be on for 2-3 weeks. In the anterior you need to make them pretty, in the posterior you do not, just functional. If you're using a light or dual cured acrylic like Integrity, a temp should take about 10-15 minutes to make tops. If you're taking more time than that, you're doing way too much! The way to ensure you have good contacts is to make the temp on the tooth, take it off, and put a pencil mark on the center of the interproximals. As long as you can still see pencil, you probably still have contact after you adjust.
If you have open margins, put the temp on the tooth, make sure there is saliva on the tooth, and put flowable composite straight on the open area and spread up to the body of the temp. Cure it, take it off, trim it up - boom closed margins. You can do this even if there is a massive hole on the tooth. I just had about 4mm of the lingual of one of my temps for a #9 break off, patched it up in two minutes, good as new, but don't go crazy if it's in a load bearing area.
Be sure you ask your patient if their bite feels "normal." Ask them if their opposite side feels like all of their teeth are coming together evenly. If not, keep adjusting those blue spots little by little until their natural teeth are all hitting "normally."
Lastly, there's something called a "Save your Ass" Bite - if you are prepping the most posterior tooth on a side, take the bite registration before you prep, otherwise their occlusion can change. Send that bite reg with the other impression.
Hope those help, good luck!
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both quads or unprepared or future prep side?
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At least the side you are prepping, but I'd say to take a whole arch bite, only takes an extra 3 seconds, and if needed the lab can just cut off the extra. One thing I've learned is the more information you give the lab the better.
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Any specific bur you like to use to create a nice chamfer? They have us using an 856, not sure if there's something "better"
Def will try this! For the depth grooves, they have us use a 57 or 877 and connect them all. The football is a 7404 right? Isn't that a finishing bur? Can you use it to connect the depth grooves without damaging the bur? (sorry if they're naive questions, we haven't been taught that much about burs yet)
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One thing that you'll often find when you hit private practice vs while in dental school, is that the number of burs of all different sizes, shapes, surface compositions, etc, etc, etc is vast! You'll may very well find that there's a bur out there that works great for you, but that the faculty in your school didn't think would be a good addition to what's available in your bur selection at school!
While I certainly use some very similar burs today, 20+ years out of school that I used in dental school, my bur block is also filled with a number of burs that just work for me better than what my dental school instructors had me learn with, Its often a bit of trial and experience when it comes to figuring out what burs work best for you to do what you need to do!
While I certainly use some very similar burs today, 20+ years out of school that I used in dental school, my bur block is also filled with a number of burs that just work for me better than what my dental school instructors had me learn with, Its often a bit of trial and experience when it comes to figuring out what burs work best for you to do what you need to do!
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Haha, I'll be honest, I can never actually remember the numbs of any diamonds other than the 830 - which is a game changing restorative bur btw haha. Imagine a 330 Diamond. Yeah, like DrJeff said, there are thousands and thousands of burs out there, and everyone finds what works in their hands. In school they have you use a more limited selection because they are the "basic" burs, ones that are very straightforward and specific purpose driven. When you get out, you start to try a bur here and there, and figure out what you like.
My direct restorative bur block is an 830, 330, 34, 2,4,6 round for slow speed (occasionally an 8 for massive caries), a flame carbide (interproximal and buccal/lingual composite shaping), a football carbide (occlusal composite adjustment / shaping), and a football diamond (all purpose need to reshape something in an aggressive way) - those burs will cover pretty much any filling I could do. Maybe throw 2-3 composite polishing burs if you're not doing amalgam.
For Indirect, like I said I'm bad with numbers, but in general I like a skinny chamfer bur (interproximal margin), a medium chamfer (buccal and lingual margins / reduction), a football diamond (occlusal / incisal reduction). Maybe use a 330 for depth grooves, and maybe a fine needle flame diamond for minor adjustments / smoothing, but otherwise you can do any crown prep with those first 3 burs.
As far as what burs to use, you need to figure out what you want to do, IE, make a chamfer, and just find a long bur that has a round end that isn't so skinny that you'll make J cuts - this is where you basically have a tiny J shaped rise / lip at the edge of your margin that will likely break off when poured, because you put the entire width of the bur internal to the edge of the margin, and instead of making a chamfer (quarter-pipe), you make a half-pipe due to the positioning of the bur.
You can do your occlusal reduction with straight burs, but I find that a big pain, and you get all sorts of jags and sharp angles if you're not super careful. A football, or possibly even better, a barrel bur, makes occlusal reduction much easier and compact. Try getting a a big long bur back to do an occlusion reduction on #15, and you'll realize you're literally pushing the back of your handpiece into the cheek to try to get the right angle.
Oh a football diamond bur looks like.... a football (American), haha, the second one down in this picture, but I like it in Coarse. Hope that helps!
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My direct restorative bur block is an 830, 330, 34, 2,4,6 round for slow speed (occasionally an 8 for massive caries), a flame carbide (interproximal and buccal/lingual composite shaping), a football carbide (occlusal composite adjustment / shaping), and a football diamond (all purpose need to reshape something in an aggressive way) - those burs will cover pretty much any filling I could do. Maybe throw 2-3 composite polishing burs if you're not doing amalgam.
For Indirect, like I said I'm bad with numbers, but in general I like a skinny chamfer bur (interproximal margin), a medium chamfer (buccal and lingual margins / reduction), a football diamond (occlusal / incisal reduction). Maybe use a 330 for depth grooves, and maybe a fine needle flame diamond for minor adjustments / smoothing, but otherwise you can do any crown prep with those first 3 burs.
As far as what burs to use, you need to figure out what you want to do, IE, make a chamfer, and just find a long bur that has a round end that isn't so skinny that you'll make J cuts - this is where you basically have a tiny J shaped rise / lip at the edge of your margin that will likely break off when poured, because you put the entire width of the bur internal to the edge of the margin, and instead of making a chamfer (quarter-pipe), you make a half-pipe due to the positioning of the bur.
You can do your occlusal reduction with straight burs, but I find that a big pain, and you get all sorts of jags and sharp angles if you're not super careful. A football, or possibly even better, a barrel bur, makes occlusal reduction much easier and compact. Try getting a a big long bur back to do an occlusion reduction on #15, and you'll realize you're literally pushing the back of your handpiece into the cheek to try to get the right angle.
Oh a football diamond bur looks like.... a football (American), haha, the second one down in this picture, but I like it in Coarse. Hope that helps!
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Ohhh okay, this is what I was confused about. Cause the footballs we have look exactly like the one you posted, and I didn't know if it'd ruin the bur to use it to do an occlusal reduction.
Yup this is what we're taught and your reasoning makes sense!
