1. Restorative Dentistry
The effect of finishing and poiishing on the decision
to repiace existing amaigam restorations
Mariane Cardoso, DDSVLuiz N, Baratieri, DDS, MS, PhD*VAndré V, Ritter, DDS""
Objective: The purpose of this investigation ivas to evaluate the influence of finishing and polishing proce-
dures on the decision to replace existing amalgam restorations. Method and materials: Twenty Ciass I
and Class il amalgam restorations, free from obvious defects, were selected in 6 patients The restorations
were photographed before and after being submitted to a standard finishing and poiishing procedure, in
the first phase, the preoperative siides were examined by 27 dinicians and senior dentai students, who
were instructed to inspect each restoration and answer a questionnaire indicating if and why the restoration
needed to be repiaced. Two weeks iater. the postoperative slides were presented to the same examiners,
who were asked to answer the same questionnaire as before. Results: At the first phase, there were 236
decisions (44%) to repiace existing amaigam restorations. Foiiowing the finishing and poiishing procedures,
114 decisions (21%) were made to repiace existing amalgam restorations. This difference was statisticaiiy
significant. Secondary caries was the most common reason for repiacement. Conclusion: The finishing
and poiishing procedure reversed the decision to repiace old amalgam restorations. (Quintessence Int
1999:30:413-418)
Key words: amalgam, clinical criteria, decision-making process
Amalgam restorations may fail and require replace-
CLINICAL RELEVANCE: A simple finishing and polish-
ment because of secondary or recurrent caries, body
ing procedure may inffuenoe the decision to replace a
fracture, marginal fractures, poor anatomic form, and,
questionable amalgam restoration.
to a lesser degree, overhangs,^'-'' However, tbe deci-
sion to maintain, repair, or replace an existing amal-
gam restoration is far from a logical process."'" Tbe
D ental amalgam bas been used as a direct restora-
tive material since tbe end of tbe last century.'
Regardless of tbe increasing use of resin composite
criteria used to make this decision are generally per-
sonal and empirical." Significant variations in treat-
ment decisions are observed not only among different
restorative materials, dental amalgam is still the most clinicians but also from tbe same person at different
widely used dental material for tbe restoration of pos-
terior teetb,^ In general, diagnosis of caries on restored teeth is
Tbe longevity of amalgam restorations varies, de- tnore complex than on unrestored teetb."'^ Despite
pending on the size of tbe cavity preparation (widtb of this complexity, a dentist spends a considerable
isthmus), tbe alloy used, and tbe tootb in question, amount of his or ber clinical time replacing restora-
among otber factors. On average, amalgam restora- tions tbat be or she judges to be unacceptable,'^-'*
tions last 6 to 11 years,''-'' Also, it bas been sbown tbat, many times, tbe new
restoration presents tbe same problems as the old
one.'"'^ In a recent in vitro study, Oleinisky et al'^
• Private Practice, Florianópoiís, Santa Catalina, Biazil, sbowed tbat the criteria used by students and clini-
"Professor and Chair, Department of Operatiue Dentislrv, Federal Uni- cians to make a treatment decision regarding old
versity af Santa Catarina, Florianópoiís, Santa Catarina, Brazil amalgam restorations are imprecise, Tbese authors
'"Alixrliaiy Professor, Department ot Operative Derlistry, Federal Univer- showed tbat tbe restoration's appearance, wbicb can
sily of Santa Catarina, Florianópolis, Santa Catarina, Brazil; Resident,
Department of Operative Dentistry and Denial Researcti Center, Uni-
be improved witb refinishing and repolisbing proce-
versity ol North Carolina at Chapel Hill, School of Dentistry, Chapel Hill, dures, significantly affected tbat decision, Tbis conclu-
North Carolina. sion was reacbed witb tbe observation tbat most deci-
fleprint requests: Dr André V, Ritter, Department of Operative Dentistry, sions to replace amalgam restorations were reversed
Uniuersity ol North Carolina at Chapel Hill, School of Dentistry, CB# 7450, after tbese restorations had been submitted to a stan-
Chapel Hill, North Carolina 27599-7450. E-mail: iHÏPERLINK maitto;
cientist@ccs, Jfsc.br Andre_Rifteredentistryunc,eöu
dard finisbing and polishing procedure.
Quintessence Internalional 413

2. • Cardoso et ai
Fig l a Occlusal view ol an amaigam restoration before bei,ng Fig 1b Occlusal view of the same tooth shown in Fig la, after
submitted to a standard finisining and polistiing procedure. the finishing and polishing procedure.
Ciinical slides corresponding to this image, as well as all the
others, were examined with x20 magnification in the reviews.
Fig 2a Occlusal view of an amalgam restoration belore being Fig 2b Occiusal view ot the same tooth shown in Fig 2a, after
submitted to a standard finishing and polishing procedure the finishing and poiishing procedure.
Fig 3a Ocolusal view of amalgam restorations before being sub- Fig 3b Occiusai view of the same tooth shown in Fig 3a. after
mitted to a standard finishing and poiishing procedure. the finishing and polishing procedure
414 Voiume 30, Number 6, IE

3. Cardoso el al
The purpose of this study was to investigate tbe
TABLE 1 Distribution of the examiners' groups
effect of refinishing and repolishing procedures on the
decision to replace existing amalgam restorations. Group Category Years ot practice n
Also, tbe reasons for the replacement decisions were 1 Senior students 0 9
assessed. The null hypothesis tested in this study was 2 Clinicians 5-10 9
that the finishing and polishing procedure does not in- 3 Clinicians 15-30 9
fluence the decision to maintain, repair, or replace old
amalgam restorations.
TABLE 2 Distribution of the examiners' answers
for the first question (decision to replace) before
METHOD AND MATERIALS
and after the finishing and polishing procedure
Twenty amalgam restorations present in 6 patients reg- Gro j p 1 • Group 2- Group 3'
ularly attending the Operative Dentistry Clinics at the Before After Before After Before After
Federal University of Santa Catarina (Fiorianópolis,
Yes 27% 9% 47% 28% 57% 43%
Santa Catarina, Brazil) were selected for the study. The No 73% 91% 72%
53% 43% 57%
University Ethics Committee approved the study, and
•Significance levels'group 1:x== 1B.99, P< 0.001; gioup 2i ;(= = 13.74,
the patients were informed about its objectives, meth- P = 0.002;grOLp3ï' = 7 51, P= 0.006.
ods, benefits, and risks. Only patients with good orai
care and general health were included in the study.
The restorations selected exhibited no evident fail-
ure. Also, only restorations with established inter-
proximal contacts were selected. Tbe type of alloy 1. Question 1 (decision to repiaee): In your opinion,
employed and the age of tbe restorations were un- docs this restoration call for repiacement?
iinown factors. Yes
Bitewing radiographs were obtained for each No
restoration before tbe initiation of the study, and infor- 2. Question 2 (reason for replacement): If your
mation regarding the patient's diet, bygiene, and use of answer for question 1 was "yes," for which reason?
fluoridated toothpaste was recorded in a patient cbart. A. Seeondary caries
This information provided some insight regarding tbe B. Body fracture
caries risk of the patient, which may influence tbe C. Deficient anatomic form (sculpture/contour)
treatment decision. D. Ditched margin
High-quality slides (occiusai view at 2:1 magnifica- E. Marginal overhangs
tion) of each restoration were obtained before (Figs F Otber
la, 2a, and 3a) and after (Figs lb, 2b, and 3b) a stan-
dardized finisbing and polisbing procedure. The fin- The same questionnaire was used before and after
ishing and polishing procedure was performed using tbe finishing and polisbing procedure. The patient's
rotary instruments at slow speed and polishing pastes anamneses information and the radiographs were
under rubber dam isoiation. avaiiable, if requested.
The preoperative and postoperative sets of slides Results were tabulated and submitted to statistical
were inspected by 3 groups of examiners (Table 1), witb analysis. Cbi-square {-/_-) and kappa tests were per-
a 2-week interval between tbe reviews. Group 1 con- formed, because tbese are measurement units on a
sisted of senior dental students from tbe Federal nominal level.
University of Santa Catarina, Schooi of Dentistry.
Groups 2 and 3 consisted of ciinicians with 5 to 10
years of practice, and 15 to 20 years of practice, respec- RESULTS
tively. At tbe first review, tbe examiners inspected only
the preoperative slides; they were not aware of the sec- Table 2 shows the distribution for tbe answers of tbe
ond stage of the study or of its objectives and method- different groups to the first question (decision to
ology. At tbe second review, tbe examiners inspected replace) before and after tbe finishing and pohsbing
the postoperative slides. Tbe slides were mounted in a procedure (first and second reviews). Ali groups ex-
magnification device (Ampligrapb, Fiorianópoiis, SC, hibited a statisticaily significant reduction in the deci-
Brazil) that provided x20 magnification. sion to replace after the experimental procedure.
The examiners completed tbe following question- Table 3 sbows tbe distribution for tbe answers to the
naire: second question (reason to replace). Secondary caries
Quimessence international 415

4. • Cardoso et ai
TABLE 3 Distribution of the examiners' answers TABLE 4 Use Of radiographs and anamneses
for the second question (reason to replace) before information (n = 27 examiners)
and after the finishing and polishing procedure
Preoperative radiographs Anamneses information
Group 1 Group 2 Group 3 Group Before After
Before After
Betöre Atter Before After Betöre After 1 4% 4%
15% 22%
49 83 52 2 11% 11% 0% 0%
Secondary 3 1% 4% 4% 4%
caries 51% 57% 48% Total 27% 37% 8% 8%
Body
fracture 15% 0% 6% 8%
Ditohed
margin 12% 16% 13% 17% 4%
Poor
anatomy 10% 16% 31% 24% 55%
Overhangs 14% 0% 2% 0% 9% •%
Other 0% 0% 1% 0% 1% 0%
"Total number oí answers lor thai particular variable.
was the most common answer to the seeond ques- for replacement in all groups (P = 0.0504), These re-
tion, both before and after the finishing and polishing sults are in accordance with the in vitro resuits re-
procedure. ported by Oleinisky et al."
Table 4 shows the frequency of requests for addi- The main reason for amalgam replacement was
tional information, ie, the anamneses chart and/or secondary caries, which is in accordance with the
radiographs. Fewer than 40% of the examiners asked findings reported by Mjör,' All 3 groups of examiners
for the radiographs, and 8% asked for the anamneses decided to replace fewer restorations because of sec-
charts. ondary caries after the finishing and polishing proce-
dure. In group 1, this reduction was 44^/0, in group 2
it was 47%, and in group 3 it was 34%. One factor
DISCUSSION that may have contributed to the change in the treat-
ment decision is the difficulty in diagnosing sec-
It is well known that the restorative dentist spends ondary caries.'-'"-'-^' This factor is responsible for
most of his or her clinical time replacing old, "failed" many false-positive diagnoses, and preventive actions
restorations.'^-" However, it has also been shown that should be implemented to minimize the subjective
the decision-making process regarding restoration nature of situations in which secondary caries is an
replacement is subjective and not based on clear issue.
criteria.'" Secondary caries should be approached the same
There is no clear protocol that defines precisely way as primary caries; ie, it is not the restoration ot
when a restoration should he replaced. However, this the defect that will cure the disease. Basic preventive
decision is made several times every day by clinicians methods, such as diet control, fluoride use, and oral
all over the world, in many cases with no scientific hygiene by the patient, should be considered in the
evidence.''-^^ This investigation showed that the crite- treatment plan to achieve low levels of primary and
ria used to decide the appropriateness of replacing secondary caries.^"^
amalgam restorations are poorly defined among the Regarding ditched margins, all 3 groups changed
groups of examiners participating in tiiis study. This their decisions after the finishing and polishing proce-
tendency is probably not confined to the loeation dure. The larger variation was observed in group 3,
examined (Florianópolis, Santa Catarina, Brazil), with a reduction of 82%. However, this result does not
because many other authors have presented similar indicate that the other groups did not notice the
results at other sites using different methods.'^•'^•^^•'•' ditched margins but rather that they did not consider
In this study, the influence of the finishing and pol- them a reason to replace the restorations.
ishing procedure on the decision to replace amalgam Poor marginal integrity seems to be a frequent
restorations is clearly demonstrated, because this pro- reason to replace restorations, although Barbakow el
cedure significantly reduced the numher of decisions aP' have shown that 100% of amalgam restoration
416 Volume 30, Number 6, 1999

5. Cardoso et al •
margins are defective 6 months after they are placed. tion will be needed in the future." This approach
Poor marginal integrity, therefore, should not justify tends to diminish the prognosis of the tooth, as a con-
the replaeement of a restoration. Either periodic recall sequence of the repetitive restorative cycle," It has
to monitor the restoration and the patient's caries risk been shown repeatedly that restorations do not cure
or the repair of the margin is preferable to total dental caries.''^^^ Also, a large number of the prob-
replaeement.-* lems in old amalgams are not solved by restoration re-
The marginal defects that appear in the tooth- placement, Ciinieians tend to believe that, "when in
restoration interface are simiiar to pit and fissure doubt, restore," which shows good faith in their own
defects hecause they act as plaque accumulation treatments. The fact that they spend more than S " of
O™
sites,'-^ Therefore, if it is possible to maintain occiusai their clinieal time replacing their own restorations and
pits and fissures free of caries, it should also be those of their colleagues demonstrates clearly that this
possible to do the same with the marginai defects in is not a good practice.'^-'« The appropriate ciinicai
old restorations. Plaque control is as caries preventive conduct should be "when in doubt, wait, obser'e, con-
in occlusal pits as it is in ditched margins, provided troi, and, if necessary, repair or repiace." The dentist
that these margins are accessible for cieaning. should always take into consideration and respect the
Many of the marginal defects diagnosed as sec- patient's needs and move toward a more health-
ondary caries could be treated conservatively with a oriented approach.
simple finishing and polishing procedure because real There is an additional point that should be
secondary caries is rare on occlusal areas.^^ improve- addressed regarding the results presented in this inves-
ments in plaque control, diet, and the correct use of tigation. The fact that finishing and polishing proce-
fluoride are additional preventive actions that should dures were able to reduce the number of decisions to
be implemented to avoid the unnecessary replacement repiace some restorations, ie, some restorations con-
of restorations.^^ sidered compromised at the first examination were
In this study, the examiners mentioned that the fact considered not compromised in the second review,
that they could not use an explorer for the reviews can be interpreted in 2 different ways. First, it can
was a problem because the observations were only be theorized that the first decision was wrong (false-
visual. However, the use of an explorer to diagnose positive), and the finishing and polishing procedure
caries is a controversial issue.'•'•'='^' Probing has shown prevented an unnecessary replacement. However, it
to be unreliable for diagnosis of caries in fissures and can also be inferred that the first decision was correct,
ditched margins.'^"" a situation in which the finishing and polishing proce-
Another frequently cited reason for replacing the dure couid have masked an existing problem, leading
restorations in this study was poor anatomic contour. to a false-negative decision; this would mcrciy have
Poorly contotired restorations can lead to periodontal. postponed necessary repair or replacement of the
occlusal, and restorative probletns.-' However, to solve existing restoration.
these problems, restorations do not aiways need to be The finishing and polishing approach proposed in
replaced," unless they are badly compromised by their this study is best suited when the clinician has control
contour, which was not the case in this study. of the patient records, mainiy radiographs and assess-
The use of bitewing radiographs is important in the ment of caries risk. Also, appropriate recalls should be
diagnosis of primary and secondary caries," especially scheduled to control for any false-negative decisions.
in Class II restorations because the cervical area is fre- All the restorations examined in the present study are
quently affected by recurrent caries.'' Espelid artd in a recali program; the long-term effects of the pro-
Tveit'-» have shown that clinical examinations, supple- posed approach will he presented in the future.
tnented by radiographie images, lead to increased sen-
sitivity in the diagnosis of secondary caries, Jokstad et
al" showed that the patient's age and caries risk are CONCLUSION
important factors among the restoration replaeement
criteria, Kidd^' also reported that information on diet, 1. The finishing and polishing procedure strongly in-
hygiene, and fluoride use are important to plan the fluenced the decision to replace or maintain existing
preventive and restorative treatment. However, very amalgam restorations {significance level: y^ — 7.51;
few examiners requested such information in the pre- P = 0.0504).
sent study- 2. Radiographs are not used routinely to make the
When an old restoration is removed, additional decision whether or not to replace an old amalgam
tooth structure is removed as well because of the restoration. Also, information about diet, oraL,
action of the bur.^ This weakens the tooth structure, hygiene, and fluoride use is seldom used as a diag-
and, therefore, it is likely that a more eomplex restora- nostic adjunct.
OL in less e nee International 417

6. • Caldoso et al
ACKNOWLEDGMENTS 16. Boyd MA, Richardson AS, Frequency of amalgam replace-
ment in general dental practice. J Can Dent Assoc 1985;51:
The authors would like lo express their gratitude to Sergio Freitas, 763-766,
DDS, Assistant Professor, Fédérai University of Santa Caiarina, 17 Elderton RJ, Assessment of the quality of restorations, A
Brazii, for his help with lhe slatisticai analysis and to Sandra L, literature review, J Oral Rebabil 1977;4:217-266,
Myers, DDS, Assistant Professor, University of Minnesota, for her 18. Elderton RJ Tbe quality of amalgam restorations. In: Allred
help in editing this manuscript. H (ed). Assessment of the Quality of Dental Care. London:
London Hospital Medical College, 1977:45-81,
19. Oleinisky JC, Baratieri LN, Ritter AV, Freitas SFT, Influence
of finishing and polishing procedures in the decision to
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