Operative dentistry aje qualtrough, jd satterthwaite la morrow, pa brunton

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Chapter 6
Adhesively retained restorations
Retention of a restoration is markedly influenced by the type of luting
cement, and restorations cemented with an adhesive lute require
much higher forces to dislodge them. Advances in adhesive tech-
niques have added another mode of treatment in addition to more
conventional techniques. Resin-based composite materials may be
reliably bonded with similar resin-based luting cements, which may
also be for luting ceramic restorations following etching and silane
treatment of the ceramic fitting surface. Base metals may be bonded to
tooth structure with bi-functional polymeric resins, for example phos-
phonated esters of Bis-GMA (bisphenol A-glycidyl methacrylate),
and gold may also be reliably bonded to tooth structure following
heat-treatment
18
(to produce a chemically active oxide layer on the
fitting surface of the restoration). Although long-term studies are 
limited, there is clinical evidence that indirect restorations bonded 
to tooth structure survive well in the oral environment
19
.
Adhesively bonded restorations may permit preservation of tooth
structure when compared with more destructive traditional options.
For example, the use of bonded restorations to prevent cusp fracture
rather than reducing and overlaying cusps. Adhesive techniques 
are also very useful when retention is at a premium and when a 
traditional preparation would involve removal of a large amount 
of healthy tooth structure or may result in exposure of the pulp.
Adhesively retained restorations often prove useful in restoring
defects caused by tooth wear/non-carious tooth tissue loss (NCTTL).
Anterior NCTTL typically occurs on palatal surfaces and these may 
be restored with cobalt–chromium or gold veneers cemented with 
resin. This technique is relatively easy. Maximal coverage up to and
including the incisal edge is provided to increase retention and aid
placement. Thin metal palatal veneers can also be used in conjunction
with labial resin composite to increase tooth length. Posterior NCTTL
can also be restored with adhesively retained gold castings, which are
useful when space is limited.
There are also situations in which adhesive restorations may prove
useful when traditional alternatives give limited options. A common
example is the situation of an upper premolar that has a large restora-
tion spanning from one proximal surface to the other across the
occlusal surface and has suffered a cusp fracture. The most con-
servative traditional treatment option would be to place a core and a