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

153
7
Maintenance of the 
restored dentition
MAINTENANCE
It is a common public misconception that a restoration requires less
care than a natural tooth; however the introduction of an interface
between the restoration and tooth surface presents a ‘weak-spot’ that
is prone to both biological and mechanical failure. It is important that
for any intervention, a maintenance programme is developed for each
patient to reduce future problems. Oral hygiene instruction and home
care form major parts of a preventive programme for each patient,
and can reduce the incidence of future disease
1
.
Whenever any restorative intervention has been undertaken, there
is an implication that disease (caries) or mechanical failure has
occurred. To place a restoration without considering these factors will
expose the restoration to an uncontrolled and unstable environment
with an increased likelihood of failure. A correct diagnosis is essential
before any treatment and in all cases, aetiological factors should be
controlled as much as is possible.
For example, if mechanical failure has presented as multiple 
fractures of teeth or restorations, provision of an occlusal splint to con-
trol and distribute the excessive occlusal forces would be of benefit.
Similarly, where failure is due to recurrent caries or there is a high
caries risk, the importance of regular exposure to fluoride should be
remembered and appropriate fluoride supplements (e.g. mouthwash)
should be advised.
Although the above steps will help to avoid failure, deterioration of
restorations is inevitable. All restorations will fail, i.e. dental restora-
tions do not have infinite service life in normal clinical conditions.
Survival time of simple restorations has been shown, in several sur-
veys, to be of the order of 5–10 years
2–5
. With high quality treatment
and a good preventive programme, then restorations may remain 
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Chapter 7
serviceable and functional for considerable periods of time. However, 
as failure is likely to occur at some point, regular review and an 
observant/aware patient will help to detect problems at an early stage
when simple remedial treatment rather than extensive treatment 
may be performed. The recognition, management and replacement of
dental restorations is therefore a routine component of the provision
of continuing dental care.
FAILURE
Although there are many studies addressing failure/longevity of
dental restorations, many of these do not provide useful information,
as the definition of failure is often not given. There is variation
between studies with regard to definition of failure with a variation
from minor deterioration to a need for operative intervention or
replacement of a restoration all being cited. The adoption of criteria
for evaluation of dental restorations set by the United States Public
Health Service (USHPS)
6
has helped to standardise assessment 
criteria, but there still exists a wide variation in the methodology of
clinical trials available to support longevity figures for various types
of restorations. Commonly identified risk factors
2,3,7,8
for increased
likelihood of failure of a restoration include gender (higher failure in
males), presence of occlusal contact (worse marginal deterioration),
number of surfaces (three surface restorations have up to 1.8
× risk of
failure compared with two surface restorations) and operator (failure
rates vary between operators with many failures being due to poor
technique).