Quest about rest seats for RPD

[TXftw]

I have a patient who wants to get a Removable partial denture. She’d be getting the denture for free through a program my school offers to patients with severe financial need. My school has given me the blessing to prepare rest seats on teeth treated with amalgam fillings. I’d be preparing probably 2 rest seats on amalgam. I recently spoke to a dentist who thinks using anything other than sound teeth or survey crowns for rest seats is a recipe for disaster and that the restorations will fracture. I kind of feel bad doing this procedure only for the denture to be unwearable in a few years due to a fractured restoration . The patient could get survey crowns but it will cost more than they can afford. Just want to get some seasoned Doctors input on the prognosis for this procedure and longevity of the denture.

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[TanMan]

I have a patient who wants to get a Removable partial denture. She’d be getting the denture for free through a program my school offers to patients with severe financial need. My school has given me the blessing to prepare rest seats on teeth treated with amalgam fillings. I’d be preparing probably 2 rest seats on amalgam. I recently spoke to a dentist who thinks using anything other than sound teeth or survey crowns for rest seats is a recipe for disaster and that the restorations will fracture. I kind of feel bad doing this procedure only for the denture to be unwearable in a few years due to a fractured restoration . The patient could get survey crowns but it will cost more than they can afford. Just want to get some seasoned Doctors input on the prognosis for this procedure and longevity of the denture.

I don't do partials or dentures, but I can at least give you some things to think about when it comes to partials and rest preps. I assume that you're doing a cast partial. Some questions to ask would be how many teeth are there, is it a distal extension, signs of bruxism/attrition, thickness of existing amalgam restoration, and patient expectations.

First, it's commendable that you care about the longevity of your partials. Most students just want credit and don't care about the longevity of their partial and just need signoffs for the requirement. So, lets explore each one:

To address your concern, if the amalam is large enough and was property condensed, then it should be able to withstand the forces placed upon it as a rest. If it's an amalgam with cusp capping, amalgam without supporting enamel, or very thin amalgam, then it's more likely to fail. Bruxism/attrition may exacerbate the longevity of aforementioned amalgam. Distal extension may or may not be a good thing for the amalgam restoration, depending if the axis of rotation is highly dependent on the Hg restoration. If it does, less likely to last, however, if the distal extension puts more pressure on the soft tissue, then it puts less pressure on the rest seat. Both a no-win situation. On a toothborne situation, it's better for ridge/soft tissue, but puts more weight on your restoration. Also, how many teeth are remaining. If it's 2-3 teeth, regardless if it's Hg or not, there might be some problems on long term prognosis. Less teeth, more force applied per tooth. Last, which is the biggest one, is patient expectations. As a dental student, it's hard to set them low, because you're not being measured on patient satisfaction, you're being measured on completion of the procedure. If you set the bar too low, patient may be disillusioned and not come fo required visits. If it's set too high, they might not be happy. In private practice, you set them low.

Now, if it fractures, it doesn't mean the partial goes in the trash. It will probably still be wearable depending on connector type. If you had to patch up the rest site, retrofit with composite is easiest. Retrofit with survey crowns or Hg is going to be more difficult due to the nature of the material.

Hopefully this answers your question and good luck!

 

[Screwtape]

I do several partials a month in private practice. I wouldn’t think twice about putting a rest prep into an amalgam (except if it’s super thin when done, then just remove the rest of it). If the amalgam does go down after the partial has been fabricated then you can always do a resin fill, press the partial into it before cure, and then cure. Works quite well. Yes survey crowns or a virgin tooth are ideal, but most times in dentistry you are not provided with ideal anything. Best of luck !

 

[Roy Williams]

I don't do partials or dentures, but I can at least give you some things to think about when it comes to partials and rest preps. I assume that you're doing a cast partial. Some questions to ask would be how many teeth are there, is it a distal extension, signs of bruxism/attrition, thickness of existing amalgam restoration, and patient expectations.

First, it's commendable that you care about the longevity of your partials. Most students just want credit and don't care about the longevity of their partial and just need signoffs for the requirement. So, lets explore each one:

To address your concern, if the amalam is large enough and was property condensed, then it should be able to withstand the forces placed upon it as a rest. If it's an amalgam with cusp capping, amalgam without supporting enamel, or very thin amalgam, then it's more likely to fail. Bruxism/attrition may exacerbate the longevity of aforementioned amalgam. Distal extension may or may not be a good thing for the amalgam restoration, depending if the axis of rotation is highly dependent on the Hg restoration. If it does, less likely to last, however, if the distal extension puts more pressure on the soft tissue, then it puts less pressure on the rest seat. Both a no-win situation. On a toothborne situation, it's better for ridge/soft tissue, but puts more weight on your restoration. Also, how many teeth are remaining. If it's 2-3 teeth, regardless if it's Hg or not, there might be some problems on long term prognosis. Less teeth, more force applied per tooth. Last, which is the biggest one, is patient expectations. As a dental student, it's hard to set them low, because you're not being measured on patient satisfaction, you're being measured on completion of the procedure. If you set the bar too low, patient may be disillusioned and not come fo required visits. If it's set too high, they might not be happy. In private practice, you set them low.

Now, if it fractures, it doesn't mean the partial goes in the trash. It will probably still be wearable depending on connector type. If you had to patch up the rest site, retrofit with composite is easiest. Retrofit with survey crowns or Hg is going to be more difficult due to the nature of the material.

Hopefully this answers your question and good luck!

How can you get away with doing no removable as a general dentist? I would love that lol.

 

[TanMan]

How can you get away with doing no removable as a general dentist? I would love that lol.

Because I have the patient flow to turn away removable... it's the best feeling ever. It's not like there's no one to do removable in my area, I end up referring to other GP's that do removables. Other GP's don't mind since they get the whole case (unless of course I needed to do something that day like an EXT or RCT due to severe pain), but otherwise, they take the good and the bad. Removable is just hell for me that provides me with no fulfillment whatsoever.

 

[Roy Williams]

Because I have the patient flow to turn away removable... it's the best feeling ever. It's not like there's no one to do removable in my area, I end up referring to other GP's that do removables. Other GP's don't mind since they get the whole case (unless of course I needed to do something that day like an EXT or RCT due to severe pain), but otherwise, they take the good and the bad. Removable is just hell for me that provides me with no fulfillment whatsoever.

I would tend to agree with that so far in my training. Question for you since I think i've seen you mention before that you think it's a better idea to go straight into practice right from dental school rather than doing an AEGD or GPR. would your position on the matter change if there were specific things I wanted to learn after dental school? I would like to get good training in implant placement, surgical extractions, bone grafts, sinus lifts, etc (other oral surgery type procedures) and incorporate those into a general dentistry practice. It seems to me like it would be better to take one year and hit it all hard (assuming I can find the right program) rather than take tons of CE over the next five years. And I understand some of those things may cut into production compared to doing other procedures, but I enjoy them and think it's something I'd want to do in my practice one day. What are your thoughts on this?

 

[TanMan]

I do several partials a month in private practice. I wouldn’t think twice about putting a rest prep into an amalgam (except if it’s super thin when done, then just remove the rest of it). If the amalgam does go down after the partial has been fabricated then you can always do a resin fill, press the partial into it before cure, and then cure. Works quite well. Yes survey crowns or a virgin tooth are ideal, but most times in dentistry you are not provided with ideal anything. Best of luck !

Only thing I'd say about resin retrofits is to be careful about engaging undercuts along with the rest seat. Sometimes, you may end up getting the partial stuck intraorally along with the resin.

I would tend to agree with that so far in my training. Question for you since I think i've seen you mention before that you think it's a better idea to go straight into practice right from dental school rather than doing an AEGD or GPR. would your position on the matter change if there were specific things I wanted to learn after dental school? I would like to get good training in implant placement, surgical extractions, bone grafts, sinus lifts, etc (other oral surgery type procedures) and incorporate those into a general dentistry practice. It seems to me like it would be better to take one year and hit it all hard (assuming I can find the right program) rather than take tons of CE over the next five years. And I understand some of those things may cut into production compared to doing other procedures, but I enjoy them and think it's something I'd want to do in my practice one day. What are your thoughts on this?

For most of what you've listed, I don't think you need to go through an AEGD/GPR to perform them at a clinically acceptable level. Simple implant placement requires understanding the fundamentals of implant placement and restorative-driven placement. Placing a "screw" aka implant is not the difficult part, but understanding the ensuing factors that will result in success. Surgical extractions are not difficult either (flap, use your drill to remove/section teeth, remove bone as needed, avoid vital structures, know how to obtain hemostasis prn), unless you're talking about FBI/PBI, however, you need to look at the realities of your compensation as a GP when performing those procedures relative to risk that you are undertaking. Most surgeons don't make money on the 3rds alone, it's all the addons that come with it such as grafting, membrane, PRP/PRF, IV sedation, "complex suturing", etc.... 1500 dollar set of wizzies suddenly became 4-5k. With bone grafting, are you talking about GBR or just simple socket augmentation? The thing I hate about GBR, it just takes forever to get a good result. I'd rather punt it off to someone who will charge as needed and let them do all the post-op management and waiting. For sinus lifts, I think it can be frustrating when you create the lateral window and end up with a perforation.

So, each one of the procedures you've mentioned has various levels of complexity without a necessarily proportional increase in compensation. If you are doing it out of interest, then perhaps an OS internship for a year might be in order if you're looking to focus more on the surgical aspects of dentistry. If you're thinking of it in terms of money, I don't think you would necessarily make more unless you were starved for patients and procedures.

Every program is different, YMMV, and I'm all for going straight to private practice. Doing a procedure 5-10 times during the course of your program isn't going to make you much more proficient than if you were to go to a weekend CE course and practice what you learned in your practice. However, you don't always have the luxury of performing the procedure many times in private practice either, so it's either you use it or lose it. For example, the most common procedure for me is molar RCT/bu/crown. Even if you were able to do it 20 molar endos in a year long program, that's about 1-2 weeks worth of molar endos in my practice. If a program could expose you to 20 lateral sinus lifts or apicoectomies, that would be a different story since I don't encounter that many apicos in my office (I don't do lateral sinus lifts)... but again, this goes back to what will you really use in your own practice. I think you should look for a program that emphasizes the procedures that you want to do, and stick to that program (or do a few weekend CE courses).