Indirect and Direct Restorative Protocols - Caulk

› PRINCIPLES & PRACTICES
Cementation Guidelines:
Clinical Recommendations
and Requisites
› Abstract:
Cementation of an indirect
restoration involves numerous
variables that include the
luting material itself and the
clinical technique used to seat
the veneer, crown, bridge,
or inlay/onlay. Composite
resin cements are often used
in conjunction with dental
adhesives and chemically
bond to numerous restorative
materials, facilitating their
adaptation to a properly
conditioned tooth surface. This
presentation discusses a series
of considerations and clinical
requisites that can aid the
practitioner in this important
phase of treatment.
In fixed prosthodontics, the clinician’s
ability to achieve an aesthetic,
functional outcome depends
on a variety of factors that
include the cementation protocol.
The luting cement used in such procedures
has to possess high compressive
and tensile strengths in addition to serving
as an adherent between the natural
tooth structures and the selected restorative
material. Among numerous other
favorable characteristics of an ideal cement
are its biocompatibility, radiopacity,
ease of delivery (eg, handling, working
time), and low film thickness. For
their part, resin cements are categorized
as one of the following based on their activation
mechanism:
■ Light-cured: Recommended for indirect
ceramic or composite restorations
less than 1.5 mm in thickness;
■ Dual-cured: Ideal in porcelain veneers,
composite veneers, and other
indications in which light penetration
is limited to 1.5 mm to 2.5 mm
through a dental restoration;
■ Chemically cured: Indicated for restorations
(eg, all-ceramic crowns, metal
restorations, intracoronal restorations
greater than 2.5 mm in thickness) that
will not transmit light upon seating.
Care should always be taken to ensure
that the cement’s shade is compatible with
the desired restoration upon seating of a
ceramic restoration (Figure 1). An ideal
resin cement will possess strong adhesive
properties and marginal integrity, and will
protect against marginal microleakage (see
Sidebar). Furthermore, its flow will be defined
by the height and taper of the preparation;
the higher and more cylindrical the
preparation, the less cement will escape,
and a greater cement line will be present.
Once the fit of the ceramic restoration
has been confirmed and its intaglio surface
has been treated, the prepared teeth should
be conditioned (Figures 2 and 3). Today’s
total-etch and self-etch adhesives simplify
the seating appointment by combining
steps (ie, etching, priming, bonding) previously
involving multiple components. If the
total-etch technique is selected, the clinician
Figure 1. Shade selection of the resin cement may signifi cantly affect
the fi nal shade of all-ceramic restorations (Courtesy: D. Greenhalgh, Mill
Creek, WA).
Figure 2. Once the tooth is conditioned, the interior of the ceramic restoration
should be treated with a silane coupling agent to improve adhesion
and ensure a durable bond.
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