Correcting Dark Veneer Margins and Two Failed Implants

The Patient's Journey

This patient came to the practice because of the dark lines along her gum line. She already had porcelain veneers, placed some years earlier, and those lines were the margins of that porcelain, uncovered where the gum had receded away from them. The appearance embarrassed her.

The recession was not incidental to the old work. The previous veneers had bulky margins, and a margin that stands proud of the tooth holds plaque against the gum. Periodontal tissue irritated for long enough recedes, and as it recedes it uncovers the junction between the porcelain and the tooth underneath. That junction is the dark line. The problem visible in the mirror was the problem sitting under the gum, which is why nothing applied to the porcelain surface would have corrected it.

Why the Implants Had Failed

Two implants in the upper arch had also failed, at a second premolar and the first molar behind it. The reasons were bone loss around both and the positions they had been placed in. Position matters because an implant transmits occlusal force directly into bone rather than through a periodontal ligament. An implant angled poorly concentrates that force where the bone is least able to carry it, and bone loaded that way is resorbed rather than maintained. Once enough has gone the implant loses stability, and remaking the restoration above it changes nothing.

Rebuilding the Sites First

Both implants were removed and both sites were grafted, because the bone that had been lost had to be replaced before a new implant could be placed into it. The replacements went in under intravenous sedation, in positions that direct occlusal force into sound bone. A provisional restoration carried her across those teeth meanwhile. Three of the five months this case took were spent on graft and implant healing.

How Dr. Mehdizadeh Approached Treatment

The design came first. The shapes of the teeth and the position of the bite were established before any preparation, so the ceramic was fabricated to a plan rather than to whatever the previous restorations had left behind.

The gum line was lifted across the upper teeth, from the second premolar on one side to the first premolar on the other, which established the heights the new restorations would be built to. Where the previous work had left bulky margins, the replacements finish flush with the tooth at the gum line, which is the condition periodontal tissue stays healthy against.

Twenty-three units were then fabricated in e.max in the practice laboratory. Seventeen are porcelain veneers, eight in the upper arch and nine in the lower. The remainder are two onlays, two inlays on the posterior teeth and two implant crowns on the replaced implants. The provisional restorations were finalized in her mouth while the definitive units were being made, so the shapes she approved were the shapes that were copied.

The occlusion was balanced once the restorations were seated, and she wears retainers.

The Result After Five Months

The dark lines are gone, and they are gone because the margins that produced them are gone. The new restorations meet the tooth at the gum without a ledge, and the periodontal tissue sits against them instead of receding. The shade and the surface texture were the other half of the brief: the shapes were designed to look natural rather than uniform, and the ceramic was finished with the surface character that natural enamel has rather than a uniform polish.

Maintenance, repair and recare were discussed and deliberately left outside the treatment plan, because they are continuing rather than part of a course of treatment. The restorations are ceramic. How long they last depends on the occlusion staying balanced, on the retainers being worn, and on the gum line staying healthy, which is where the previous work failed.