Operative is killing me!

[zombies]

Advertisement - Members don't see this ad

Hey guys,
We just started operative and my preps look awful! I know what the shapes are supposed to be, but I can't make myself physically do it. I've experimented with a couple of different burs. One of my biggest problems knowing how to get started. I've tried the dropping dots method but then connecting the dots with straight lines and curved lines is all messed up. For whatever reason, when going into the central groove, one surface will have more stuff removed than the other. I can't get it centered.
And when I go up into the grooves and try to make the isthmus it screws up everything else. Either one cusp gets shredded or everything ends up too fat or the cusp ends up becoming flat.
PLEASE HELP!

 

[Stephie3]

are you trying to do a class I? sounds like it to me anyways. use a 330 on slow speed to drop some depth points to 1.5. try making many more depth points than you are making now and know the head of the 330 bur is 1.8 mm, so keep your eye on the head of the bur and dont totally submerge the head. then for connecting the dots, i use a 169, this time using the highspeed. lightly back and forth, back and forth, shaving away tooth structure until i've connected two depth points.

after you've used the 169 to connect the depth points, make the isthmus a little bigger to where you can fit a 330 bur in it. then use your 330 bur on slow speed to smooth out the floors and walls. if you watch the head of the 330 bur (1.8 mm tall) then it will keep you from accientally making your prep too deep. the 330 bur will also put the converge you need in the walls.

drop some depth points in the places you need the grooves, then use a diverging bur to point divergence in the dovetails and places where you need it.

if you put slow speed on reverse, it doesnt cut anything, only smooths it. you can scrap the floor with a hatchet to do some final smoothing too.

one thing about operative lab when you've taking the practicals...dont try to initally make it perfect. learn to "underprep" and then go back and make it perfect if you have time. what i mean is this...if 2 mm is the ideal depth, first cut it somwhere between 1.5 and 2 mm. then if you have time you can try to cut it to the perfect depth just perfectly. this way you dont overshoot stuff when you're going back to finish it and polish it.

 

[zriceman]

Hey guys,
We just started operative and my preps look awful! I know what the shapes are supposed to be, but I can't make myself physically do it. I've experimented with a couple of different burs. One of my biggest problems knowing how to get started. I've tried the dropping dots method but then connecting the dots with straight lines and curved lines is all messed up. For whatever reason, when going into the central groove, one surface will have more stuff removed than the other. I can't get it centered.
And when I go up into the grooves and try to make the isthmus it screws up everything else. Either one cusp gets shredded or everything ends up too fat or the cusp ends up becoming flat.
PLEASE HELP!

been there. done that. just practice lots. I had nightmares when i first started operative. Now its hella easier. Keep on chugging.

 

[zombies]

Thanks guys for your replies! I'm going to give it another go today in the lab. I'll let you know how it goes. Hopefully, it gets better because all these Ivorine teeth I've been using are starting to add up, haha.

 

[zombies]

Okay, I think today has been a definite improvement since yesterday. I tried outlining with a 1/4 bur, defining it more with a bur that has a ball at the end, followed by a 329. Then I smoothed everything out with a 245/330 on slow speed. Here's some pictures of what I did today.

I'm still having problems keeping the dimensions correct. Our instructors are real stickers for the dimensions, so any advice would be appreciated.

http://i1111.photobucket.com/albums/h479/zombies2/photo1.jpg
http://i1111.photobucket.com/albums/h479/zombies2/photo.jpg
http://i1111.photobucket.com/albums/h479/zombies2/photo3.jpg

THANK YOU!!

 

[sokrman14]

Your outline form (shape) of your prep is just not correct. These are all ideal plastic teeth, and the outline form should be obvious on them. You need to look at those specific teeth in your book to get them correct.

 

[zombies]

Your outline form (shape) of your prep is just not correct. These are all ideal plastic teeth, and the outline form should be obvious on them. You need to look at those specific teeth in your book to get them correct.

We do have some pictures of outlines to look at, so I do have a good idea of what it looks like. For whatever reason (and I keep on seeing this over and over in my preps) two cusps will come out okay, but the other two will be flat and open up too much into the central groove. Why does this keep on happening? And how can I not do that anymore? It shows up in both of my preps of #19.

 

[sokrman14]

I would practice on #18 first. Its an easier outline form. It looks identical to the batman logo. Make sure that you extend your dovetails into each groove more. Its 1/4-1/3 way up each cusp and 1/3-1/2 up each groove.

 

[dentheartthrob]

try using a 245 bur. for me, it take away the hassle of switching from one bur to another

 

[IdahoDoc]

Thanks guys for your replies! I'm going to give it another go today in the lab. I'll let you know how it goes. Hopefully, it gets better because all these Ivorine teeth I've been using are starting to add up, haha.

You have to pay for the teeth you use? They aren't included in tuition?

 

[newyorkblork]

You have to pay for the teeth you use? They aren't included in tuition?

Same for NYU.

Improve quickly, or spend 18++ bucks a week (1.80 per tooth)... I'm going through mine like candy

 

[Vicviper]

Okay, I think today has been a definite improvement since yesterday. I tried outlining with a 1/4 bur, defining it more with a bur that has a ball at the end, followed by a 329. Then I smoothed everything out with a 245/330 on slow speed. Here's some pictures of what I did today.

I'm still having problems keeping the dimensions correct. Our instructors are real stickers for the dimensions, so any advice would be appreciated.

http://i1111.photobucket.com/albums/h479/zombies2/photo1.jpg
http://i1111.photobucket.com/albums/h479/zombies2/photo.jpg
http://i1111.photobucket.com/albums/h479/zombies2/photo3.jpg

THANK YOU!!

I'm a little confused at the outline of your preps - as a previous poster said, they just don't look quite right. For one, your preps seems to be a bit too curved - it looks like you're trying a bit too much to avoid hitting any of some of the cusp inclines. I think if you just go for a more straight prep, it'll turn out much better. I call this prep the "Rocketship" - you've got two tails going to each side of the distal cusp, and then the body down the central groove, with fins going to the buccal and lingual. The entire prep (as far as we were taught it) should look more or less like this: >-|-

And, one of the biggest tips I can give is that Less is More here - the more work you keep doing to get it to be just perfect usually ends up with it looking worse - though I know it's hard to deny that temptation to just "fix one little thing" - it's gotten me a number of times in pre-clinic.

Good luck!

W'OOT! 2,000th POST!

 

[DrReo]

Try to stay off the inclines of the cusps. . .

 

[zombies]

Same for NYU.

Improve quickly, or spend 18++ bucks a week (1.80 per tooth)... I'm going through mine like candy

Agreed. Spent $25 yesterday on some teeth!

I think I'm getting better. Modified pen grip is awesome, but sometimes I can't see anything because of the way the handpiece is positioned. So then, when I'm try to go up from the central groove, disaster strikes because a. can't see anything and b. just hoping that my handpiece finds the right place.

Going from distal and pulling towards me helps a lot.

Definitely agree with less is more! Nothing can truly be perfect unfortunately.

 

[zombies]

Hey, do you guys have any suggestions for burs that are not side-cutting and just make the preps deeper?

 

[sokrman14]

Hey, do you guys have any suggestions for burs that are not side-cutting and just make the preps deeper?

A 34/36 is mainly bottom cutting, but can cut with the side as well. Just don't bang it against the wall and you'll be good

 

[Vicviper]

Hey, do you guys have any suggestions for burs that are not side-cutting and just make the preps deeper?

I believe the 957 is the bottom cutting bur that we have - but be careful when you use it because it's easy to make a trench with bottom cutting burs if you apply too much force.

 

[zombies]

I believe the 957 is the bottom cutting bur that we have - but be careful when you use it because it's easy to make a trench with bottom cutting burs if you apply too much force.

Yes...Very easy. I've gotten pretty good results on the mandibular, but whenever I try anything on the maxillary arch...Disaster strikes! I think that's moreso of learning how to do things using indirect vision.

 

[scottyhoop]

I agree with the above comments...check out what the ideal outline form is supposed to be and just practice alot. I use a 330 for everything and then maybe go in with a hatchet if i have some minor wall smoothing to do. Also...your tooth on the first pic is in the wrong side of the arch i think...the distal cusp is on the lingual. Maybe you just had it that way for the pic?? Practice is key...you'll get it!

Scotty

 

[scottyhoop]

Btw...did you try drawing your outline on the tooth with a sharpie before cutting the tooth?? I did that at first and it helped a lot. And disregard my wrong side comment...i see they are all on 19 so you prolly just had it there for the pic.

Scotty

 

[Runnin Doc]

Try to use a 329 or 330. They are bottom cutting, pear shaped burs and give you an accurate depth of the cut (meaning that the cutting surface extends 1 mm and 1.5 mm, respectively, into the tooth). However, when they dull out, like all carbide burs, their cutting becomes very inefficient. I use these two for cutting almost all operative preps and then use a 34 or a 37 (inverted cones) to smooth out the pulpal and gingival floors. Combos of these seem to work best for me! Operative is all about getting comfortable with the burs you have available to you. Practice, find some burs you like, and stick with them... It gets a lot easier the more you practice! Good Luck!

 

[efitzger]

I completely agree with the methodology below. I do initial outlines with a 330 or 245 (depending on depth I need) in my high speed handpiece, then smooth pulpal walls with an inverted cone in the low speed. Works like a charm.

Once the outline is correct, smoothing the walls is quite simple with a slow speed; sipmly follow the contours of your prep while applying light pressure.

The only other advice I can offer to the original poster is to go slow at first. Memorize the ideal outline for the tooth you are working on. Know the measurements you want (isthmus/depth/etc.). Practice on a learner block (cheaper than teeth) and find which burs work for you in particular situations (i.e. tapered fissure is great for divergent mesial/distal walls).

Do small class I preps (the same one several times) and you'll get it.

Regarding indirect vision...practice. There's no easy way around this. Easiest (cheapest) way to practice this is to simply try to draw the outline form with a pencil on the tooth while holding a mirror. Once you master that, you're ready to swap the pencil for the drill. Muscle memory is a beautiful thing.

Try to use a 329 or 330. They are bottom cutting, pear shaped burs and give you an accurate depth of the cut (meaning that the cutting surface extends 1 mm and 1.5 mm, respectively, into the tooth). However, when they dull out, like all carbide burs, their cutting becomes very inefficient. I use these two for cutting almost all operative preps and then use a 34 or a 37 (inverted cones) to smooth out the pulpal and gingival floors. Combos of these seem to work best for me! Operative is all about getting comfortable with the burs you have available to you. Practice, find some burs you like, and stick with them... It gets a lot easier the more you practice! Good Luck!

 

[peerless218]

Ok speaking of operative. When you guys have practicals, what do you guys do to stay calm? I normally cut decent to good preps but when it comes to practicals, I only cut clinically accecptable preps because I am darn nervous. I am really thinking about taking a shot before my next practical. I really dislike the ugly preps I cut on test days and it drives me nuts to know the quality of my normal work aren't being performed:-(

And as for the operative question. Class one occlusal is what you're probably working on right now. I don't know what kind of bur you use at your school. At UOP, we use the carbide 330 bur, which is 1.5 mm deep. I usually make sure about 1/4-1/5 of my bur is showing above the tooth on the occlusal and stay on the central groove through out the prep design. 2nd step would be using the carbide 56 to refine the buc lingual wall, and making the proper isthmus width. Then finally, after I make my outline form, I use a dull 330 old bur that I have, and I slowly use that bur with a slowspeed to refine the floor until I hit the 1st line on the thompson condenser. It should also look nice and shining when you're done with your refinement.

 

[newyorkblork]

Ok speaking of operative. When you guys have practicals, what do you guys do to stay calm? I normally cut decent to good preps but when it comes to practicals, I only cut clinically acceptable preps because I am darn nervous. I am really thinking about taking a shot before my next practical. I really dislike the ugly preps I cut on test days and it drives me nuts to know the quality of my normal work aren't being performed:-(

This is gonna sound corny, but I use visualization techniques. Just imagining the practical beforehand, say the morning of, and really thinking about how nervous you might feel, and then taking a breath and reminding yourself that you've practiced a ton, that nothing "unlucky" will happen if you take it slow and do what you've always done, and that you're actually quite decent at this game, then visualizing every step of the prep before you actually walk into the room... it helps me get my nerves straight and put my game face on.

Then when I'm inside the room, I set everything aside extra carefully and cleanly, and start drilling my little practice pad (I don't know if you have one, but just moving the drill calms me down), making smooth curves before getting into the actual typodont. This helps remind me that the drill is my tool, and that I'm in control, not "bad luck". It helps slow my brain down - haste is the quickest way to screw yourself on a practical.

This actually worked too well for me - I ended up being so relaxed that I screwed up my timing, and ended up not having enough time! So don't relax yourself too much ;-)

 

[peerless218]

Thanks for the advice. Boy, the practical I had on Thursday had to be the worst one, #4 MOD. I am not sure my hands were shaking because I was nervous or because I did not eat breakfast. They shook for the entire 2 hours while I was preping. I couldn't even get a good indirect vision because my left hand was shaking like a mad man. Glad I passed but I wasn't happy with the score. For those of you who are treating patients, what do you guys find it to be more stressful? Treating patients or taking a practical?

 

[danialclarcke]

Thank you for your reply! I'm going to give it another go today in the laboratory. I'll let you know how to. Hope it gets better, because all these Ivorine beginning I have been using teeth together.

 

[Ryltar]

are you trying to do a class I? sounds like it to me anyways. use a 330 on slow speed to drop some depth points to 1.5. try making many more depth points than you are making now and know the head of the 330 bur is 1.8 mm, so keep your eye on the head of the bur and dont totally submerge the head. then for connecting the dots, i use a 169, this time using the highspeed. lightly back and forth, back and forth, shaving away tooth structure until i've connected two depth points.

The head of the bur is actually 1.5mm, although not dropping your initial cuts to 1.5mm is good advice because your prep usually becomes about .3mm deeper when you finish the pulpal floor and walls.

 

[LNinlove]

The head of the bur is actually 1.5mm

Actually it's 1.6mm...
http://www.brasselerusa.com/products/discdcarbides.cfm?id=22

To the OP, just keep practicing, you will get it. As others have mentioned, it's much easier to take a little bit of tooth structure away then it is to put it back in. Also, I know some in my class trace the prep with a .5mm pencil before doing the prep. I have tried it a couple times and it seems to work fine.

Best of luck to you! 👍