FGC Open Margin

[Darya]

I seated a gold crown last week, took a BW and all margings looked close on the xray, so I cemented it. but after cleaning up the cement the ML corner is open about 1/2 mm. The occlusion and proximal contacts are right on!

I did not mention it to the instructor, but have been thinking about it all week 🙁

I am wondering if I could fix it with just adding some GI in the gap!!!

Help please ...

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[crazy_sherm]

1/2 mm is an unacceptable amount of gap for a crown margin. Filling it with GI or resin won't last and the patient will end up with a leaking crown. The best thing to do would be to figure out why the margin is open, learn from your mistakes, and redo the crown. Your goal while in school should be to learn how to do things right, not develop bad habits.

 

[Cold Front]

1/2 mm is an unacceptable amount of gap for a crown margin. Filling it with GI or resin won't last and the patient will end up with a leaking crown. The best thing to do would be to figure out why the margin is open, learn from your mistakes, and redo the crown. Your goal while in school should be to learn how to do things right, not develop bad habits.

Ditto.

BWX alone won't work. Using an explorer should have allowed the OP to catch the open margin before cementing the crown, that 0.5mm would have been spotted for sure.

I usually use a bite stick to push the crown down, then use the explorer to check open margins. You can usually solve this type of problem by burnishing.

 

[Darya]

could it be burnished after it's cemented???

 

[reapply2007]

of course you could burnish after cementing. this might reduce the gap to .4 mm. this crown either needs to come off and be reseated or redone entirely, both of which will likely happen after caries hits the open margin. wher

 

[Darya]

I've never had any luck removing crowns w/s cutting them ... If anyone has any tips, I'd appreciate it.

This has been occupying my mind all week, that's why I posted my question here .... off course I don't want any recurrent caries to happen!

 

[NileBDS]

I've never had any luck removing crowns w/s cutting them ... If anyone has any tips, I'd appreciate it.

This has been occupying my mind all week, that's why I posted my question here .... off course I don't want any recurrent caries to happen!

Darya ... it's happened to all of us in one occasion or the other while in dental school ! Whether it is the situation you described, or others like broken files, endodontic perforations, pulpal exposures, ... I could go on and on and on.

The way you CHOOSE to handle this predicament will tell you alot about how you will handle them in private practice. Sherm is right on the money ! If you have any inclination now towards brushing this under the rug, and hoping you either forget about it or it becomes someone else's problem in a few years, then now is the time to correct that thought process and establish an appropriate way of dealing with such mishaps. School is the time to do it, because lawyers are not very compassionate teachers.

To put things into perspective, this is one of the easiest situations you may have to deal with. Ever. Would you rather tell your patient "I'm sorry, I think I need to make you a new crown", or "I'm sorry, but I extracted the wrong tooth" ? The whole situation is really not even worth your worrying about it for the past week. School is stressful enough ! This should be one less thing on your mind.

This is what I would do:
If you have a nice/reasonable patient, then approach it in a very straightforward and candid way, and explain the situation to her yourself.
If you have an abusive/PITA patient, then you need to find an instructor you like, make them aware of what heppened, and have them do the talking for you.

Once this is all said and done, you will
1. Fell much better
2. Be prepared to handled much bigger disasters later on in life
3. Be a lot more attentive when seating crowns
4. Will not feel guilty about this for the rest of your life

 

[Darya]

Nile,

I truly appreciate your advice,

I won't be seeing the pt for a few months until his recall... at that point, I will talk to him and explain the situation and consult with one of my instructors.

I will re-make the crown!
Lesson learned.... check the margins with an explore before cementing!!!

Thanks everyone for your inputs.

 

[tinman831]

Nile,

I truly appreciate your advice,

I won't be seeing the pt for a few months until his recall... at that point, I will talk to him and explain the situation and consult with one of my instructors.

I will re-make the crown!
Lesson learned.... check the margins with an explore before cementing!!!

Thanks everyone for your inputs.

You said the margins "looked" closed. Are you saying you never checked them with an explorer? Depending on your patients oral hygiene, waiting "a few months" could result in more recurrent caries. If you know for a fact that the margins are open, you need to get your patient in as soon as possible. Waiting 5 months till his next recare exam and then bringing it up is negligence. Your patient might not be too happy that you knew of the problem yet ignored it until then. Trying to get your patient in now shows that you actually care for your patient.

 

[Cold Front]

You said the margins "looked" closed. Are you saying you never checked them with an explorer? Depending on your patients oral hygiene, waiting "a few months" could result in more recurrent caries. If you know for a fact that the margins are open, you need to get your patient in as soon as possible. Waiting 5 months till his next recare exam and then bringing it up is negligence. Your patient might not be too happy that you knew of the problem yet ignored it until then. Trying to get your patient in now shows that you actually care for your patient.

+1.

Also, the OP should have documented his/her findings (.5mm open margin after the cementation - and all the steps prior to the cementation) in the patient's chart. Think of the situation as if you were in private practice, 30 seconds chart note(s) is you best friend in any procedure.

When OP brings the patient back, they should be honest and professional. Don't over explain the problem, as patient's are only interested in solutions.

 

[DrJeff]

I seated a gold crown last week, took a BW and all margings looked close on the xray, so I cemented it. but after cleaning up the cement the ML corner is open about 1/2 mm. The occlusion and proximal contacts are right on!

I did not mention it to the instructor, but have been thinking about it all week 🙁

I am wondering if I could fix it with just adding some GI in the gap!!!

Help please ...

Is the margin of the FGC just short in that ML corner or is the gap due to an overhang?? I'm guessing it's short based on what you've posted, but if it's an overhang, then given that it's an FGC, you might very well be able to trim/burnish that margin until it's flush and you'll be OK without having to redo the crown.

If its short, well then has been said, a "patch" job won't cut it longterm and a redo is the proper treatment.

Learning time though. 1) I'm sure now that you'll never go to mix the cement prior to checking those margins with an explorer 360 degrees around the tooth. 2) Don't beat yourself up about this, its happened to ALL clinicians at one time or another(and sometimes even after checking the margins due to cement issues). Learn from what happened, as personally I find that I learn about 10 times more from my errors than from my successes 3) Try and figure out why this happened in the 1st place. If the margins of the FGC are fine the remaining 7/8ths of that tooth, chances are it's not do to lab error in the waxing/casting of that FGC, but an error in the impression. Take a good close look at that ML corner in the impression and see if you really captured all the detail. Once again - don't beat yourself up about this, there are so many clinicians out there that miss anatomical details in their impresssions, but if that's the case, learn from it and ask your professor to help you with making sure that you capture all the details in the impression as very often it's the line angles that present the problem.

Bottomline, if it's open, you need to redo it, but also use this as an academic event and try and figure out what went wrong, because if you do, you'll be WWAAYY more likely to never make the same mistake again!👍

 

[Cold Front]

IF the patient is geriatric, then I probably wouldn't re-do the crown. A glass ionomer or composite would be enough to seal the open margin.

IF the patient is not geriatric, then I would re-do the crown.

 

[OceanDMD]

IF the patient is geriatric, then I probably wouldn't re-do the crown. A glass ionomer or composite would be enough to seal the open margin.

IF the patient is not geriatric, then I would re-do the crown.

WTF...!!!! So, a "geriatric" doesnt deserve the same standard of dental care as everyone else? Does the "geriatric" pay less for the services rendered? You might want to rethink your thinking here. Its wrong.

 

[Cold Front]

WTF...!!!! So, a "geriatric" doesnt deserve the same standard of dental care as everyone else? Does the "geriatric" pay less for the services rendered? You might want to rethink your thinking here. Its wrong.

Relax.

I'm just saying that it wouldn't make any sense to make an 80 yr old patient to go through the exhausting process again; cutting the crown and getting it off > rep-prep the tooth > final impression > cementation with possible complications from re-prep'd tooth. That's at least another 4 appointments for an old patient, plus they have already gone through enough from previous crown. A simple composite or glass ionomer can fill that .5mm open margin. This alternative may not the best option, but works well enough clinically and in the patient's comfort level if it's done correctly.

You are telling me you would tell the 80 yrs old patient, "Sorry, we have to start this all over again, and I will see you 4 more times despite your delicate health.". Even better, have a sign at the front door of your office, "Frail people are treated the same as robust people". You have to consider patient management, and not just treating a tooth.

 

[DrJeff]

Relax.

I'm just saying that it wouldn't make any sense to make an 80 yr old patient to go through the exhausting process again; cutting the crown and getting it off > rep-prep the tooth > final impression > cementation with possible complications from re-prep'd tooth. That's at least another 4 appointments for an old patient, plus they have already gone through enough from previous crown. A simple composite or glass ionomer can fill that .5mm open margin. This alternative may not the best option, but works well enough clinically and in the patient's comfort level if it's done correctly.

You are telling me you would tell the 80 yrs old patient, "Sorry, we have to start this all over again, and I will see you 4 more times despite your delicate health.". Even better, have a sign at the front door of your office, "Frail people are treated the same as robust people". You have to consider patient management, and not just treating a tooth.

When working on geriatric patients(as I'm literally going to do as soon as I'm done typing!) a majority of time the question/concept of 'I'm old, do I really need this' comes up, and the way I answer this question is really quite simple.... "how many more years are you going to live??" They don't know the answer, you don't know the answer, and it happens all to often when you go "conservative" on a geriatric patient because you think that they may have a year or 2 left, they'll live for WAY longer than you thought and you'll be repairing that tooth since you tried to cut corners in the 1st place. About the only time I'll regularly go "conservative" on a tooth is when we're talking caries on a primary tooth with 85%+ root resorption. Other than that, you just don't have a solid grasp as to how long YOUR work is going to have to last in that patients mouth.

 

[OceanDMD]

Relax.

I'm just saying that it wouldn't make any sense to make an 80 yr old patient to go through the exhausting process again; cutting the crown and getting it off > rep-prep the tooth > final impression > cementation with possible complications from re-prep'd tooth. That's at least another 4 appointments for an old patient, plus they have already gone through enough from previous crown. A simple composite or glass ionomer can fill that .5mm open margin. This alternative may not the best option, but works well enough clinically and in the patient's comfort level if it's done correctly.

You are telling me you would tell the 80 yrs old patient, "Sorry, we have to start this all over again, and I will see you 4 more times despite your delicate health.". Even better, have a sign at the front door of your office, "Frail people are treated the same as robust people". You have to consider patient management, and not just treating a tooth.

What makes you think (in this scenario) the tooth needs reprepped?
"simple glass ionomers/composites" leak. Its a compromise. It is not standard of care. I have seen patients with these issues walk in my office "doc, I just had this crown done a year ago, now it is sensitive". Cut the crown off, decay that results in a irrev pulpitis, and now the patient needs not only a new crown, but an RCT. An 80 year old can sue your ass off just as easily as a 40 year old.

Look, I can't say I have not used the same reasoning as you in the past. What I am saying is that it wrong. Just the other month I had a 73 year old, has been fighting cancer, walk into my office as a new patient. He was missing #20, #19 had a broken ml cusp (most common cusp in the dentition to break imho), and thus needed a crown. What goes through my mind, "lets patch this thing and stabilize him". Here is what I offer the patient:

1-#19 MODB gigantic resin. Pros-inexpensive. Cons- May not last long term, aking alot out of a reisn this size (FYI, I dont do pin amalgams)

2- #19 PFM pros- longterm restoration. Cons- expensive

3- #19-21 FPD (why not. I have to offer him this with the missing tooth even though he is very sick) Pros - longterm restoration that replaces missing tooth. Cons- Very expensive and I have to prep #21

Surprise surprise. He likes the idea of getting that missing tooth fixed, regardless of what his 5 year survival rate is. He chooses the bridge. I have already inserted it. Bottom line, treat every patient the same. Obviously treatment may be altered for certain health conditions, as far as I know age is not one.

 

[Daurang]

There shouldn't even be a discussion. The right thing to do is take an hour and redo the crown; you will feel better and sleep better which leads to a happier satisfying life knowing you've done the right thing. Cut the crown in half and send it back to the lab for redo. I'm sure the lab will either redo it for free or split the cost with you, which isn't much to begin with.

 

[davefan]

I seated a gold crown last week, took a BW and all margings looked close on the xray, so I cemented it. but after cleaning up the cement the ML corner is open about 1/2 mm. The occlusion and proximal contacts are right on!

I did not mention it to the instructor, but have been thinking about it all week 🙁

I am wondering if I could fix it with just adding some GI in the gap!!!

Help please ...

It really does need to be redone. I understand in dental school that you want to please the instructors and not have to redo things. However, the best learning I believe is when you make mistakes and the best time to make these mistakes are in dental school. Mistakes happen. Don't beat yourself up over it. Just redo the crown and move on. Good luck!

 

[tinman831]

I understand in dental school that you want to please the instructors and not have to redo things.

What are you talking about? I've had to take THREE FINAL impressions on a patient before. There's just no pleasing some instructors. 😛 Try explaining the need for a third one to the patient. 😳

 

[Cold Front]

What makes you think (in this scenario) the tooth needs reprepped?
"simple glass ionomers/composites" leak. Its a compromise. It is not standard of care. I have seen patients with these issues walk in my office "doc, I just had this crown done a year ago, now it is sensitive". Cut the crown off, decay that results in a irrev pulpitis, and now the patient needs not only a new crown, but an RCT. An 80 year old can sue your ass off just as easily as a 40 year old.

Look, I can't say I have not used the same reasoning as you in the past. What I am saying is that it wrong. Just the other month I had a 73 year old, has been fighting cancer, walk into my office as a new patient. He was missing #20, #19 had a broken ml cusp (most common cusp in the dentition to break imho), and thus needed a crown. What goes through my mind, "lets patch this thing and stabilize him". Here is what I offer the patient:

1-#19 MODB gigantic resin. Pros-inexpensive. Cons- May not last long term, aking alot out of a reisn this size (FYI, I dont do pin amalgams)

2- #19 PFM pros- longterm restoration. Cons- expensive

3- #19-21 FPD (why not. I have to offer him this with the missing tooth even though he is very sick) Pros - longterm restoration that replaces missing tooth. Cons- Very expensive and I have to prep #21

Surprise surprise. He likes the idea of getting that missing tooth fixed, regardless of what his 5 year survival rate is. He chooses the bridge. I have already inserted it. Bottom line, treat every patient the same. Obviously treatment may be altered for certain health conditions, as far as I know age is not one.

The age issue... Most dentists assume that they are equipped with all the knowledge and skills required to treat the dental problems of the elderly, but this is not always so. A parallel can be drawn with pediatric dentistry.

The open margin issue... we are just debating about something that we both directly didn't see, and know it's exact severity. It's simply dead wrong to simply look at a tooth and disregard other things, particularly for most senior citizens (in my opinion). I have seen dentists who don't even check a patient's medical history before tx begins, so the of standard care may be the same for all, but it can be managed on a case by case basis - nothing unethical or illegal about it. Anyways, I hate debating about clinical dentistry without seeing the actual findings. It's like politics, we could both be right, but then one of us feels the other doesn't know what he is talking about. So I am stepping aside on this. 🙄

 

[armorshell]

What are you talking about? I've had to take THREE FINAL impressions on a patient before. There's just no pleasing some instructors. 😛 Try explaining the need for a third one to the patient. 😳

Only 3? The depressing low standards at dental schools these days...

 

[Thaxil]

In this situation, I would take the 30mins to remake the crown. The patient paid for a clinically acceptable crown and deserve it. However, age and health are consideration in the initial treatment planning. I do fewer crowns on the elderly then on a robust young adult that is a night bruxer.

 

[OceanDMD]

The age issue... Most dentists assume that they are equipped with all the knowledge and skills required to treat the dental problems of the elderly, but this is not always so. A parallel can be drawn with pediatric dentistry.

The open margin issue... we are just debating about something that we both directly didn't see, and know it's exact severity. It's simply dead wrong to simply look at a tooth and disregard other things, particularly for most senior citizens (in my opinion). I have seen dentists who don't even check a patient's medical history before tx begins, so the of standard care may be the same for all, but it can be managed on a case by case basis - nothing unethical or illegal about it. Anyways, I hate debating about clinical dentistry without seeing the actual findings. It's like politics, we could both be right, but then one of us feels the other doesn't know what he is talking about. So I am stepping aside on this. 🙄

No. Its not like politics. You are wrong. Its wise to "step aside".

 

[Cold Front]

No. Its not like politics. You are wrong. Its wise to "step aside".

I can't find my "why so serious?" image... 😀

The crown issue aside, I still disagree with your premise of "age is nothing but a number!".

 

[Cold Front]

In this situation, I would take the 30mins to remake the crown. The patient paid for a clinically acceptable crown and deserve it. However, age and health are consideration in the initial treatment planning. I do fewer crowns on the elderly then on a robust young adult that is a night bruxer.

Geriatrics are considered to be at significant risk of being harmed by treatment intended to benefit them. This is an area that is not well taught in dental school.

 

[DrJeff]

Geriatrics are considered to be at significant risk of being harmed by treatment intended to benefit them. This is an area that is not well taught in dental school.

Yes, and sometimes that treatment "intended to benefit them" may be UNDERTREATMENT because of perceived not to distant mortality concerns.

Just remember that "patch" you do on a 70 year old in this day and age may very well have to last 20 years before old age gets them, similarly that beautiful implant crown you do on a 40 year old may only need to last a year before the heart attack get them 😱 You never know

 

[NileBDS]

Nile,

I truly appreciate your advice,

I won't be seeing the pt for a few months until his recall... at that point, I will talk to him and explain the situation and consult with one of my instructors.

I will re-make the crown!
Lesson learned.... check the margins with an explore before cementing!!!

Thanks everyone for your inputs.

Not a problem.

Anyone of us is prone to this sort of situation. What I personally do when seating crowns is (once all other adjustments have been done and only when the crown is a go for cementation):

• Load the cement
• Seat the crown with firm pressure/bite stick/have patient bite on cotton roll ... whatever
• Immediately run your explorer again from the crown margin to the tooth structure and back. All around. Make sure it is not openanywhere and that the crown has fully seated (before the cement fully sets)
• To double check,I do the articulating paper right away. If the crown is all of a sudden in hyperocclusion, or the only tooth touching, then it is obviously not seated all the way, at which point you either have the patient bite again to try seat it all the way, or remove the crown (before the cement sets) and rinse and go back to step, one. Rinse and repeat until desired results have been achieved. 🙂

I do not use bitewings all the time. Not even most of the time. I personally feel fitchecker gives you a 3-D representation of the margin, opposed to a 2-D radiograph. That's just me though.
Bitewings would probably better show overhanging margins, which can be evaluated else wise.

 

[DrJeff]

Not a problem.

Anyone of us is prone to this sort of situation. What I personally do when seating crowns is (once all other adjustments have been done and only when the crown is a go for cementation):

• Load the cement
• Seat the crown with firm pressure/bite stick/have patient bite on cotton roll ... whatever
• Immediately run your explorer again from the crown margin to the tooth structure and back. All around. Make sure it is not openanywhere and that the crown has fully seated (before the cement fully sets)
• To double check,I do the articulating paper right away. If the crown is all of a sudden in hyperocclusion, or the only tooth touching, then it is obviously not seated all the way, at which point you either have the patient bite again to try seat it all the way, or remove the crown (before the cement sets) and rinse and go back to step, one. Rinse and repeat until desired results have been achieved. 🙂

I do not use bitewings all the time. Not even most of the time. I personally feel fitchecker gives you a 3-D representation of the margin, opposed to a 2-D radiograph. That's just me though.
Bitewings would probably better show overhanging margins, which can be evaluated else wise.

Fit checker, for me too, is definately one of those little things that I really couldn't practice without! 👍

 

[Goatswalk]

I seated a gold crown last week, took a BW and all margings looked close on the xray, so I cemented it. but after cleaning up the cement the ML corner is open about 1/2 mm. The occlusion and proximal contacts are right on!

I did not mention it to the instructor, but have been thinking about it all week 🙁

I am wondering if I could fix it with just adding some GI in the gap!!!

Help please ...

Ethics, Ethics...Ethics!!...DO IT OVER!!!! PATCHING THIS UP IS UNETHICAL....DO YOU PATCH UP YOUR SINK WITH GLUE WHEN THE PIPES ARE LEAKING? What if I put a .5mm open margin crown on your tooth, while you knowing it's going to leak and decay in time??...You see what that feels like?....That's why it's best to go to TOP SCHOOLS!!

 

[Goatswalk]

I seated a gold crown last week, took a BW and all margings looked close on the xray, so I cemented it. but after cleaning up the cement the ML corner is open about 1/2 mm. The occlusion and proximal contacts are right on!

I did not mention it to the instructor, but have been thinking about it all week 🙁

I am wondering if I could fix it with just adding some GI in the gap!!!

Help please ...

Don't be the example of this Generation who knew how to pass test to get into graduate schools AND pass test to get out of graduate school b/c they are seeking the doctor profession to make money....a student who went to school with the passion of making sure patients are WELL TAKEN CARED OF will not ASK THIS QUESTION!!....GET IT TOGETHER!!....THESE ARE PEOPLE HERE, WHO ARE IN NEED OF DOCTORS TO PUT THE PATIENT FIRST AND NOT THE DOCTOR!!!

I GIVE YOU A F+++ FOR LETTING THAT PATIENT LEAVES!!

 

[Goatswalk]

There shouldn't even be a discussion. The right thing to do is take an hour and redo the crown; you will feel better and sleep better which leads to a happier satisfying life knowing you've done the right thing. Cut the crown in half and send it back to the lab for redo. I'm sure the lab will either redo it for free or split the cost with you, which isn't much to begin with.

You know, it is a question, for this GENERATION who thinks passing test Merits them title of doctor, when clearly 95% of these kids are from middle class and low income backgrounds are here for Monetary purposes and not the Art and Passion of taking care of the Dentally, and Medically Challenged!!!

It's a sad reality...b/c at the end of the day, I would take a 2.5GPA kid with a good heart and academic potential than one who has Top Marks for the wrong reasons!!

 

[Goatswalk]

Nile,

I truly appreciate your advice,

I won't be seeing the pt for a few months until his recall... at that point, I will talk to him and explain the situation and consult with one of my instructors.

I will re-make the crown!
Lesson learned.... check the margins with an explore before cementing!!!

Thanks everyone for your inputs.

Dara,

All these comments are harsh, but they are the truth. However, we are all people and no one is born with the right way to do things...As people we have the capacity to develop into that most perfect doctor patients dream of....Questions like yours, makes people like you better Doctors...Continue asking questions, and over time, the asking become little b/c you grow from your questions and mistakes; notwithstanding the harsh truthful comments.....Good luck and always put them first like we want Moma to be first!!!!...That solves all those ethical 'delimma's'(I can't spell that word to save my life)!!!

 

[doc toothache]

Relax. I'm just saying that it wouldn't make any sense to make an 80 yr old patient to go through the exhausting process again; cutting the crown and getting it off > rep-prep the tooth > final impression > cementation with possible complications from re-prep'd tooth.

The question then would be why even bother putting a crown on an 80 year old in the first go around?

 

[Cold Front]

Fit checker, for me too, is definately one of those little things that I really couldn't practice without! 👍

I use occlude here and there.

To be good at fit checking, you need to have an eye for detail, as labs sometimes send crowns back with fuzzy margins or margins covered by porcelain.

What cement do you prefer for FPD cases?

 

[doc toothache]

To be good at fit checking, you need to have an eye for detail, as labs sometimes send crowns back with fuzzy margins or margins covered by porcelain.

"Fuzzy margins" may be coming from "fuzzy" impressions.

 

[NileBDS]

I use occlude here and there.

To be good at fit checking, you need to have an eye for detail, as labs sometimes send crowns back with fuzzy margins or margins covered by porcelain.

What cement do you prefer for FPD cases?

Man, you and Darya are not getting any love on this thread. 🙂

Fujicem works for me. Ever since rely-x started setting on me while I was cementing a post for #8, I never looked back !

How do you get the occlude off ? I remember using it in school for RPD's, but cleaning was a pain !

 

[tinman831]

Fujicem works for me. Ever since rely-x started setting on me while I was cementing a post for #8, I never looked back !

How do you get the occlude off ? I remember using it in school for RPD's, but cleaning was a pain !

Maybe I'm impatient or just not mixing completely, but I find that it takes too long for the Rely-X to set when I'm cementing posts.

And the occlude just comes off with a blast of water/air. Just don't get it all over your hands and gloves... makes for a big mess.

 

[DrJeff]

I use occlude here and there.

To be good at fit checking, you need to have an eye for detail, as labs sometimes send crowns back with fuzzy margins or margins covered by porcelain.

What cement do you prefer for FPD cases?

Rely-x is my cement of choice. Heck I've been using it (or it's former name Vitremere) now for over a decade and it's comforting for me to see that for my own cases that the only failures I see with it can be attributed to either lack of patient care of the restoration😡 (read as LOTS of new caries and not just on the tooth with my restoration/cement) or b) my poor judgement in case design of the restoration 😱😡

As for fuzzy margins, I've had a heck of a lot less of them (not that I had a ton before) ever since my lab started scanning in the die's and integrating using cad/cam into the design/fabrication of the restoration (kind of scary though sometimes if the lab sends me an e-mail with attached data of what my prep looks like all blown up in the 21" monitor I have on my desk in my office 😱 😉

 

[DrJeff]

Maybe I'm impatient or just not mixing completely, but I find that it takes too long for the Rely-X to set when I'm cementing posts.

And the occlude just comes off with a blast of water/air. Just don't get it all over your hands and gloves... makes for a big mess.

Take it from someone who definately has an impatient streak in them. Get one of those little digital kitchen timers, and use it when cementing and heck even sometimes during impression taking! Makes a difference more than you may think!

Either that or in private practice you cement and then go do a couple of hygiene checks or screw around on the internet for a few minutes to allow that stuff to completely set 😀

 

[fjk]

Were the crown margins checked on the die before trying it in the patient? We check all crowns on their dies under a scope before being approved for try-in, is this standard protocol?

I'm confused as to how a 0.5mm open margin would appear if it seats well on the die and the occlusion, as you reported, is spot on (so it is not an error in cementation). Unless of course the margin was damaged after the impression was taken, or the impression was poor/damaged.

 

[80B]

OR...when the tooth was prepped, you left a 0.5mm lip of enamel at the edge of the chamfer on the ML, this was recorded in the impression, and the crown was fabricated flush to this lip. In the time between the final impression and the delivery of the crown, this thin lip of enamel fractured off, leaving you with a 0.5mm gap in the margin. Just a theory.