Chairside - Glidewell Dental Labs

Figure 1: A smile in need of a remake. The patient requested a porcelain
makeover of the esthetic zone with occlusal corrections to prevent future
porcelain fracture. The posterior bridgework is clinically acceptable; however,
the anterior abutments in the esthetic zone will require resurfacing to
match the anterior units.
Figure 2: Preparations for porcelain veneers on tooth #27 and #28. The
small metal exposures will not appreciably affect the bond of the veneers
to the porcelain surface.
Figure 3: A 2x magnified facial view of the veneer preparations
Figure 4: A dentin desensitizer with antibacterial agent (AcquaSeal B,
AcquaMed Technologies) is applied to cleanse the prepared tooth surface
prior to the etching procedure.
If the broken restoration is a single unit, a complete remake
may be the most predicable solution. But what about
multiple-unit fixed bridgework? It may not be feasible
economically or clinically to sacrifice a long-span restoration
for one unit with a porcelain fracture. In esthetic cases, a
clinically acceptable posterior bridge may not be the same
shade as the one chosen for the anterior reconstruction. So,
for these clinical problems, is there a long-term solution
short of replacing the entire restoration?
Reveneering Existing Porcelain Restorations
The patient in Figure 1 presented with the desire to remake
his porcelain reconstruction. Some of the anterior units
were fractured due to occlusal issues. The patient’s desire
was to remake the restorations in the esthetic zone with a
high value shade. The posterior bridgework was clinically
acceptable, but the shade was much lower in value and hue
than the desired anterior shade. Figure 2 shows a segment
of this reconstruction, where an old single-unit crown was
replaced and a veneer preparation was made into the existing
anterior abutment of the posterior bridge immediately distal
to it. The key to success with this procedure is the original
thickness of porcelain on the existing bridge. The goal is
to have little or no metal exposed. Tooth #27 and #28 are
prepared for stacked porcelain veneer restorations (Fig. 3).
The total thickness of the labial reduction of the natural
tooth surface and porcelain surface is 0.5 mm facially and
1 mm incisally.
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