Clinical Protocols for Adhesive Inlay and Onlay Restorations on Teeth #18 and #19
Michael J. Koczarski, DDS
A 28-year-old male patient presented with failing amalgam
restorations and interproximal decay on teeth #18 through #21 and pain elicited
with direct pressure to the mesiobuccal cusp of tooth #19. Based on the
abfractional wear patterns on the cuspal tips of tooth #19, it was evident that
the patient had a history of nocturnal bruxism and resultant occlusal wear
(Figure 1). The undermined mesiobuccal cusp of tooth #19, the failing
restoration, and the decay of teeth #18, #20 and #21 required treatment with a
restorative material that was durable, yet kind to the opposing dentition. Two
direct ceramic optimized polymer restorations were to be performed for teeth
#20 and #21, and a fiber-reinforced polymer onlay restoration and a polymer
inlay were selected for teeth #19 and #18, respectively. The patient consented
to the treatment plan and the procedure was initiated.
Using the shade guide, the base shade was recorded from the
buccolingual one-third. The enamel shade comprised the occlusal one half and
margins of the restoration, establishing a natural transition from enamel to ceramic
optimized polymer. Detailed shade mapping or clinical photography was required
in order to achieve detailed characterization. Shade selection occurred prior
to actual preparation and possible dentinal dehydration, which could have
altered the selection. In order to facilitate provisional fabrication, an index
was also taken of the preparation site with fast-setting bite registration
material. This information was forwarded to the laboratory to be developed in
the definitive restorations.
Caries indicator was used to facilitate removal of all
infected tooth structures. The preparation requirements were facilitated with the
use of diamond burs (Figure 2). Due to its dimensional stability, the
impression was subsequently taken with a polyvinylsiloxane material. An
internal or "stump" shade was taken of the preparation to ensure
proper shade blend with the existing dentition. In order to support occlusal
load, provisional restorations were fabricated with the aid of a bisacrylic
material, and cemented with a noneugenol provisional cement (Figure 3).
Upon receipt of the laboratory-fabricated restorations, the
patient was prepared for intraoral try-in. A rubber dam was placed in order to
facilitate isolation of the site.1 Upon removal of the provisional
restorations, the preparations were cleaned and disinfected with an
antimicrobial rinse mixed with a pumice slurry (Figure 4). The restorations
were evaluated for material integrity and marginal adaptation on the models to
ensure that no voids were present (Figure 5). The restorations were placed in
the preparations for final evaluation of marginal integrity and adaptation,
appropriate contact, and color match (Figure 6). Proper shade match was
evaluated with the aid of try-in paste. In order to avoid postoperative
sensitivity, the preparations were not permitted to become desiccated during
the try-in and subsequent bonding steps.2
Once properly fitted, the restorations required surface
conditioning. When internal surfaces were altered, the internal aspects of the
restoration were cleaned and/or microetched prior to surface conditioning. The
internal surface was washed and acidified with 37% phosphoric acid and
thoroughly rinsed, dried, and coated with silane for 60 seconds. A warm-air
dryer was used to evaporate the excess liquid.
The tooth preparations were acid-etched with 37% phosphoric
acid for 10 to 15 seconds using the total-etch technique to facilitate proper
bond strengths.3 In the total-etch technique, the enamel was
initially trimmed with acid and etched for 5 seconds (Figure 7). This was
immediately followed by filling the rest of the preparation with acid etch and
allowing it to stand an additional 10 seconds (Figure 8). Once the dentin and
enamel were etched for 10 and 15 seconds, respectively, an antibacterial
solution was applied to act as a rewetting agent. Excess liquid was blotted
dry, leaving a moist preparation.
The dentin primer was placed (Figure 9) and allowed to
penetrate for 30 seconds. A warm-air dryer was used for 15 seconds to evaporate
any acetone or alcohol residue. Dual-cured bonding resin was subsequently
applied to all internal surfaces of the preparations as well as the bonding
surfaces of the surface-conditioned restorations (Figure 10). A mixture of the
dual-curing, radiopaque, and fluoride-releasing luting cement was carefully
placed into the preparations, and the restorations were seated.
Excess material was removed with a rubber-tipped instrument
(Figure 11). Care was taken to remove all excess cement from the restoration.
The restorations were tacked in place with a 1-mm argon laser-curing tip for 1
second on the facial margin. The curing light was not applied to the
interproximal areas (Figure 12) to avoid accidental curing of the uncleaned
areas. Meticulous care was exercised to remove all excess cement prior to final
cure. A dry brush or rubber-tipped instrument and explorer were used for
interproximal flossing to facilitate finishing of interproximal areas (Figure
13). Glycerin gel was applied in order to prevent the formation of an
oxygen-inhibition layer at all margins, which enhanced the composite cure at
the cavosurface.4 Final curing was accomplished with an argon laser
for 10 seconds per surface for each restoration (Figure 14).
Excess cured cement at the margins was removed with a
curette, carbide finishing bur, and a diamond bur (Figures 15 and 16).
Retraction cords were removed prior to any finishing, which facilitated the
removal of any remaining excess composite material at the gingival margins. Any
cement in the interproximal areas was removed with an interproximal scaler, #12
scalpel blade, and an interproximal metal strip.
Final polishing (Figures 17 and 18) was accomplished using
polishing cups and polishing paste. The rubber dam was removed and the
occlusion was evaluated and adjusted (Figure 19). Centric and lateral excursions
were verified. The restorations were then etched and resealed with a surface
sealer in order to ensure prolonged longevity (Figures 20 and 21). The
definitive restoration exhibited aesthetics, color, and contour that were
indistinguishable from the natural dentition (Figure 22). The restorations
replaced the weakened cuspal tissues of tooth #19, restored the teeth to
consummate anatomical form, and eliminated discomfort upon occlusal function.
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to wet dentin surfaces. J Esthet Dent 1992. 123(9):35-43.
P, Noack MJ, Roulet JF. Marginal adaptation with glass ceramic inlays
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