In a previous article in this series I showed an example of masking an extremely dark crown prep by using an opaque cored crown and subgingival margin. This article will discuss using an opaque masking agent and opacious composite to allow the use of a more translucent final restoration

Discolored endodontically-treated central incisor, existing metal ceramic crowns

This patient presented unhappy with the appearance of his old metal ceramic crowns and the wear on his other anterior teeth. In addition, the gingival levels of the centrals would benefit from crown lengthening, particularly the right central (Fig. 1). Removing the crowns revealed an extremely dark prep on the left central (Fig. 2).

In the previous article I showed a similar prep masked with an Alumina core. In this case I was also restoring the right central, both laterals and canines, all which were normal in color. I decided to mask the prep with a highly opaque material (Kerr Kolor-Plus), followed by an opacious composite (3M Filtek Supreme shade A-1 dentin).

This allows the technician to use a more translucent final restoration, which ultimately makes it easier to match the other restorations. The masking is done by prepping an additional few tenths of a millimeter into the darker areas, followed by etching and bonding, then the Kolor-Plus to mask, overlayed by the composite to bring the shade closer to normal (Fig. 2-4).

In this case, the technician chose powder and liquid ceramics for the veneers, and Zirconia cores with powder and liquid ceramics over the cores layered very similar to the veneers. This case could have been done similar to case four in the previous article, where I did all the masking with the opaque core of the final restoration, but I would have used the opaque cores on both centrals to achieve an acceptable match between them.

The composite masking meant I didn’t need to use the opaque core on either central. Since the left central required a subgingival margin to hide the junction of light and dark, I also placed the margin of the right central subgingival to get a good match, even though all the veneers on the laterals and canines have supragingival margins (Fig. 5).

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Comments

Commenter's Profile Image Prashant Kaushik
April 11th, 2014
Frank, I noticed that tooth 11 has recession but it was still restored with a veneer. Can the patient get a graft later and will its success be undermined by the current veneer? Or should the graft have been done earlier to the veneer? I come across these scenarios and unless it is showing in the full smile picture, patient's usually don't care if it is grafted. Nevertheless, beautiful case!
Commenter's Profile Image Gerald Benjamin
April 12th, 2014
Do we know why we have a thickened, rolled margin on the crowns of 8 and 9?
Commenter's Profile Image Frank Spear
April 12th, 2014
Prashant, it may not be evident from the final photos, but the veneer margin on the left canine is 1.5 to 2mm supragingival, at the CEJ, allowing the veneer to be bonded to enamel cervically. This allows for a future graft to cover the root if necessary, in addition it typically results in a more pleasing final esthetic. If we carry the margin to the gingiva when we have recession, the tooth looks too long unless a root colored ceramic is used. Gerald, I didn't show the whole case focusing on the discolored central, but both centrals had 2 to 2.5mm of facial crown lengthening via osseous surgery, this effectively moves the margin apically onto the root surface, and also to a more lingual position due to the tapering of the root. It is not uncommon to see a thicker gingival margin in such instances.
Commenter's Profile Image Prashant Kaushik
April 12th, 2014
Frank, I appreciate your reply. So going forward, if the patient wanted to graft tooth 11, it should be o.k., with the supragingival margin? I assume that ideally would want the area grafted first then restored or does it matter, vice versa? Thanks kindly.
Commenter's Profile Image Gerald Benjamin
April 12th, 2014
Frank; I was not being critical. This is a tissue response around crowns that appear perfectly (i.e. contour,margin placement, lack of retained cement, lack of traumatic occlusion and no plaque) that I see (and place) and yet no one can explain WHY this happens.
Commenter's Profile Image Frank Spear
April 13th, 2014
Prashant, correct, as long as the restoration is placed at or above the CEJ, the timing of the graft being done before or after won't matter, especially when using translucent all ceramic restorations whose margins don't need to be hidden by gingiva. If you were using a restoration which required a subgingival margin for esthetics, such as a metal ceramic FPD abutment, then having the graft done first so you definitively know the gingival margin position, and can place your margin below it, may be beneficial. Gerald, didn't take it as you being critical, but now better understand the question. I agree with you, we all have crowns placed that show a thickened or rolled gingival margin. I can't tell you why in all cases, but I do suspect subgingival contour is responsible in some cases. Back in the 1970's Morton Amsterdam and his group at Penn used to speak on the concept of a "double deflecting" contour on teeth with recession and periodontal disease. The concept was that you could produce a thinner more normal gingival margin if your restoration provided a fuller, more convex, emergence profile subgingivally, followed by a second convex profile, starting more coronally, where the CEJ should have been. The concept was that the first profile produced a thin knife edge gingival margin, the second convex profile produced a deflecting contour to prevent food from damaging the thin gingiva. The concept was lost somewhere in the 80's, but they did show several clinical examples back in the day where the fuller emergence profile eliminated the rolled tissue returning the gingival form to what we see more commonly on natural teeth. Food for thought anyway.
Commenter's Profile Image Gerald Benjamin
April 13th, 2014
Thanks Frank for your answer. This thickened,rolled margin has been both problematic and a mystery since none of the normal criteria that produce negative gingival responses are evident in many cases. This reminds me of my wife's case where I placed the gingival margins supra gingival and still suffered generalized gingival recession. Dentistry is a lot like golf...you think you have it and then you lose it . lol
Commenter's Profile Image Mouth Care
April 18th, 2014
I have read an article about oil pulling, and it said that it's very good for treating this kind of mouth problem. My brother even tried it and yes it's really effective. Try reading those infos in this site http://www.badmouths.org/sweet-taste-in-mouth/
Commenter's Profile Image Anu Wadivkar
May 24th, 2014
Great Case!! I am currently working on a similar case. Can you comment on the cements used ,both for the veneers and the crowns. How much does shade of cements matter for veneers vs crowns? My thought is it does effect veneers due to thickness however for crowns it would depend on the ability of the core to mask color or not. Please comment. Thank you, Anu