Post Lava Crown: Black Line Still Present?

I got three old PMF crowns (molars) replaced with three Lava crowns just recently. I am wondering why there is still some kind of darkness in between the three crowns and a black line on the back of the crowns (just where the visible black line of the PMF´s from the metal used to be).

These new ones are real Lava crowns and metal free so I thought there should no black line be visible even on the back of the tooth. Also why are the spaces in between these three teeth a little darker?

Doctor Answers 9

Porcelain crowns, discoloration

the new material from lava is supposed to be free of any dark underlying material so my guess it is probably 1 of 2 things

1. leakage of bacterial from the crown margin and the tooth below. was there any darkness when first inserted? if not then this is probably the problem, solution is to replace crown

2. the second option is that the root of the tooth is dark and discolored from previous root canal therapy. this is much harder to fix and either a connective tissue graft to thicken the soft tissue or an acellular dermal graft such as alloderm could be used to cover dark root. the crown may still have to be replaced to reposition the margin

Lava Crowns, black lines, old porcelain fused to metal crowns, implants, incision-less implants, flapless implant surgery

The roots of your teeth are still dark from having old metal crowns on those teeth for a while. Two solutions: both require re-doing the crowns.

1. Drill out a trough in the dark roots and fill with opaque resin, boding. This is called the "Dickerson Ditch" name by Bill Dickerson DDS from Nevada.

2. Make the crowns subgingival; ending under the gumline.

Dr. Josephs

Mitchell A. Josephs, DDS
Palm Beach Dentist
5.0 out of 5 stars 1 review

Should I have Dark Lines around my Lava Crowns?

In general, the answer is that  Lava (a type of 3M Zirconia, all-ceramic porcelain crown) creates a beautiful invisible crown.  In general, there is usually a nice improvement over the darkness of a PFM (porcelain fused to metal dental crown). The dark spaces in between your teeth are likely minor gum changes that will improve by itself in a few weeks.

Your dark lines could be temporary or permanent.

They could be temporary and caused by:

  • The gum being pushed down during the impression or fitting process.
  • The shape of your new Lava dental crown being slimmer than the old PFM crown or the temporary crown.
  • Some gum cleaning chemicals can leave a dark residue.

The dark lines could be permanent and caused by:

  • Internal darkness in the tooth itself, especially if it has had a root canal.
  • The new crown margin fitting slightly higher than the gum line, revealing the darker colored tooth
  • Contamination or bleeding during the cementation of your crowns.

If these are back teeth, then I would contact your cosmetic dentist and have him recheck them. Odds are high that the darkness will seem to disappear or at least improve over a few weeks. Make sure to show him exactly what you see so he can ease your mind. 

Remember, these are a prosthesis, just like a glass eye. They are not real, but made to look as real as possible. Most of the time Lave dental crowns produce a really nice cosmetic result, but there are limitations, especially if this is the second time you are having these crowns made.

Like other cosmetic dentistry concerns, the key is to discuss your expectations and have clear communication. Thanks, Scott Greenhalgh, DDS.


Lava Crown

Just as Lance said, this is probably because of visably being able to see the tooth strucrture. If there is recession present after the prep, many times the gum will cover the area after a period of time. A photo would be great to be able to tell better.

Phillip Kemp, DDS
Brentwood Dentist
5.0 out of 5 stars 2 reviews

Black lines on dental crowns can happen for many reasons

Sometimes the tooth structure itself is dark and can show.  If there is any gum recession, this will appear, however sometimes it shows immediately after the crown is placed and the gums return to normal and hide the black line.

It is possible that some fluid was trapped during cementation and has stained.  Unfortunately, this won't go away.

As far as the other discolorations, without a photo I can't guess...

Lance Timmerman, DMD, MAGD
Seattle Dentist
4.3 out of 5 stars 6 reviews

Darkness around Lava Crowns

Drs. Spector and Timmerman make valid points about your concerns. The darkness between the teeth may be the result of recession of the gum - which will rebound over the next 3 -6 months if the contour of the tooth in relation to the bone height is correct (5mm from bone to contact area). It may also be a change in shape of the new crowns relative to the old crowns. The old crowns may have been too bulky and new ones properly contoured. Patients often a very concerned about the spaces (called dark triangle disease) when observing them up close in a mirror, when in fact the spaces do not show in normal lighting, shadow of your lip, saliva present, and at a 3 foot speaking distance. I hope this information helps you further.

Mickey Bernstein, DDS
Memphis Dentist
5.0 out of 5 stars 1 review

Darkness Can Be Reflected in New Dental Work

Metal free crowns can still show the darkness of the tooth structure underneath.    The darkness can reflect the color of an old root canal treatment, it can be from recession, it can even be an illusion.  The key is where are your new crowns?

If your front teeth are involved, the darkness can be an issue.  An interesting treatment I have done for perfect crowns that show a color difference is to have a periodontist do gum grafts to thicken the tissue and cover the area. 

Usually, I don't do that right after new crowns so you need to talk to your dentist and discuss your concerns.  If recession has occurred in the new crown process, which it can, just re-do the crowns.  Dentists do their best and you must remember it is still the practice of dentistry-Keep lines of communication open.

If the crowns are in the back, the darkness may not be as big of an issue.  The color in between your teeth can also appear dark just because of shape and contour of the crowns.  It can also do with the gum tissue-Healing can affect the gum margin and you may need to wait awhile to access the color after the gums have healed.

-Good luck and don't get upset.

Wendy S. Spektor, DDS
Bellevue Dentist
5.0 out of 5 stars 3 reviews

Darkness above Lava crown

Successful dental treatment  is a result of the teamwork. This team consists of patient, restorative doctor and the team of specialist that he or she works with, and laboratory. If any of team members did not performed well, there is a high probability that the final result might not be satisfactory. The fact that you have received Lava crown doesn't mean that you will have an excellent aesthetic result. It is just a dental material. The most important is how experienced was your restorative dentist and if he was able to control the whole "team" ( that I mentioned before). There could be multiple reasons why you have a dark line above your crown margins and in between the crowns, but that has to be analyzed by a dental specialist and only then you will find an answer to your question.

Zina Kaleinikova, DDS, MS
Cleveland Dentist
5.0 out of 5 stars 2 reviews

Lava Crown with a Black Line

Without more information it is difficult to say for sure what is causing the black line on your Lava crowns.  One thing that comes to mind is that the Lava Crown is often considered in the category of Porcelain crowns.  There are many materials that a dentist can select from when doing a Porcelain crown.  Lava crowns consist of Zirconium, which is actually a  white metal.  This is important because metal does not allow light to shine through the crown  to the underlying tooth structure.  This then often creates a dark looking tooth structure (black line).   Using a porcelain material that is translucent and will allow light to shine through can often eliminate the black line from occurring.  This is just one reason that I thought may be causing the dark line on your crowns.  There are many others that can also be contributing to it.  I would recommend consulting with your treating dentist and allow him/her to evaluate it.

Randy Bryson, DMD
Las Vegas Dentist

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.