Difficulties in creating a class I amalgam preparation

[Dental Student In Need]

Hello everyone,
I'm a student and we just started working on class I amalgam preparations. I keep practicing but constantly get the same mediocre results.
The floors and walls of my preparations are always bumpy and I can't seem to fix it without eventually making the preparation too deep or too wide.

Does anyone have tips on how to improve that? Our school only allows us to use 330 burs.

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[TopDog]

Hello everyone,
I'm a student and we just started working on class I amalgam preparations. I keep practicing but constantly get the same mediocre results.
The floors and walls of my preparations are always bumpy and I can't seem to fix it without eventually making the preparation too deep or too wide.

Does anyone have tips on how to improve that? Our school only allows us to use 330 burs.

Hello everyone,
I'm a student and we just started working on class I amalgam preparations. I keep practicing but constantly get the same mediocre results.
The floors and walls of my preparations are always bumpy and I can't seem to fix it without eventually making the preparation too deep or too wide.

Does anyone have tips on how to improve that? Our school only allows us to use 330 burs.

Go over everything lightly with a 330 diamond on slow speed

 

[DocMon16]

I haven't done one of these in a long time...I will tell you that plastic teeth are tougher to make smooth, just my .02. It comes with time and developing a steady hand to make these preps to the desired dimensions and smooth. Keep practicing...I found that once you do enough...a brand new bur that cuts well with an air turbine and water, you can get really nice results. But to each their own...a new bur maybe scary to use at first because it will take away a lot of tooth structure if you're not careful.

 

[Lemillion]

It’s harder to explain how to improve in this situation via a post but my advice would be to reach out to an upperclassmen that’s showing good operative skills so far. I reached out to an upperclassmen back in the day and it made a world of difference having some one on one time with them. I would get them a small gift card for lunch afterwards if so.

If you don’t know who, feel free to ask one of the operative faculty. In dental school, the faculty had a list of students of the class above that had done well in operative 1 and 2 who would be willing to help.

 

[nealofgrafton]

Cut inital outline prep a little on the 'small' side with your 330 then switch over to a fresh 330 in a slow speed to make that turd shine

 

[bracketbuster68]

You’re new to using handpieces so it’ll be hard at first. Learn how to control the rheostat by using different levels of pressure with your foot. You can even fine tune that pressure by stepping on the rheostat with different parts of your foot (toes, heels, big toe, etc) until you find something comfortable that gives you good control.

Another important thing to keep in mind is 1) how hard you are holding the handpiece and 2) how hard you are pushing the handpiece/bur when you are cutting. The faster you run the handpiece, the faster the bur will cut. The harder you push the handpiece when cutting, the faster the bur will cut. Most importantly, the harder you grip the handpiece, the less tactile sensation you’ll feel. In my opinion, getting the feel of the bur cutting as you are prepping is one of the important skills you can develop. So stop holding the handpiece so tight and experiment with different speeds and pressures until you feel you have total control of the handpiece. You should be feeling the floor of the prep as you cut it. If you walls are narrow enough, you should be feeling those as well while you’re drilling.

Lastly, use the length of the bur to your advantage. 330 burs are 1.5mm so don’t go crazy past the depth of the bur. When you cut your prep, it should be pretty smooth if you use controlled strokes. If you need to smoothen your prep, crank the rheostat up and use very delicate hand pressure on the handpiece. The bur will do the cutting for you. If you feel that you can’t do this without applying a ton of pressure - your bur is dull and you need a new one.

 

[cluelessdr]

i was in your exact spot when i started doing class I preps last semester. first competency i got one of the lowest grades (D) and second practical/competency I got one of the highest grades (A). I asked faculty for extra teeth to practice on, and i practiced every week and it helped a ton. i only used a 169 bur for the whole prep just adjust your rpms. its all about lower rpm to about 150k for initial cut and steady hand, and always always keep your bur along the long axis of the tooth. you'll get it eventually even when you dont think you will, just do as many as you can

 

[8_man]

Get used to handling a high-speed handpiece. Drilling on high-speed will allow the bur to smoothen floors and walls with minimal to no pressure, whereas with a slow-speed handpiece, you are pretty much forced to apply significant pressure to get any timely results. This is where I would find myself applying a bit too much pressure in one area versus another, leading to an uneven floor. Cutting the tooth like butter on high-speed makes the job much easier (but it does take some time to develop these skills, hence you should start now).

When working on high-speed, just glide the base of the bur over the floor. The downward pressure you should be exerting is literally just the weight of the handpiece itself. No additional pressure from your hands.

 

[MLC45]

I found that once I got use to using a hand piece things got better. In the meantime, I would recommend you drop the RPM's to about 10-20,000 to do a final polish using the 330's. That should take any rough edges off and help smooth things after the final prep is made. Sometimes if I have a challenging prep or patient I might still do this just to make sure things are smooth and the way I want it in the end. As you get more skilled you won't need to take things so slow to make sure the walls/floor are smooth. Hope this helps.