Clin Oral Invest (2010) 14:349–366

DOI 10.1007/s00784-010-0432-8

ORIGINAL ARTICLE

FDI World Dental Federation: clinical criteria

for the evaluation of direct and indirect restorations—update
and clinical examples
Reinhard Hickel & Arnd Peschke & Martin Tyas & Ivar Mjör & Stephen Bayne &
Mathilde Peters & Karl-Anton Hiller & Ross Randall & Guido Vanherle &
Siegward D. Heintze

Received: 11 May 2010 / Accepted: 2 June 2010 / Published online: 14 July 2010
# Springer-Verlag 2010

Abstract In 2007, new clinical criteria were approved by categorized into three groups: esthetic parameters (four
the FDI World Dental Federation and simultaneously criteria), functional parameters (six criteria) and biolog-
published in three dental journals. The criteria were ical parameters (six criteria). Each criterion can be
expressed with five scores, three for acceptable and two
for non-acceptable (one for reparable and one for
By agreement between the editors in chief this paper is simultaneously
published in J Adhes Dent 12, 2010. replacement). The criteria have been used in several
clinical studies since 2007, and the resulting experience
R. Hickel (*)
Department of Operative Dentistry and Periodontology, in their application has led to a requirement to modify
Ludwig-Maximilians-University, some of the criteria and scores. The two major alterations
Goethestrasse 70, involve staining and approximal contacts. As staining of
80336 Munich, Germany the margins and the surface has different causes, both
e-mail: hickel@dent.med.uni-muenchen.de
phenomena do not appear simultaneously. Thus, staining
A. Peschke : S. D. Heintze has been differentiated into marginal staining and surface
Research & Development, Ivoclar Vivadent, staining. The approximal contact now appears under the
Schaan, Liechtenstein name “approximal anatomic form” as the approximal
M. Tyas contour is a specific, often non-esthetic issue that cannot
Melbourne Dental School, University of Melbourne, be integrated into the criterion “esthetic anatomical
Melbourne, Australia form”. In 2008, a web-based training and calibration
tool called e-calib (www.e-calib.info) was made avail-
I. Mjör
College of Dentistry, University of Florida, able. Clinical investigators and other research workers
Gainesville, FL, USA can train and calibrate themselves interactively by
assessing clinical cases of posterior restorations which
S. Bayne : M. Peters are presented as high-quality pictures. Currently, about
Department of Cariology, Restorative Sciences, and Endodontics,
University of Michigan School of Dentistry, 300 clinical cases are included in the database which is
Ann Arbor, MI, USA regularly updated. Training for eight of the 16 clinical
criteria is available in the program: “Surface lustre”;
K.-A. Hiller “Staining (surface, margins)”; “Color match and translu-
Department of Operative Dentistry and Periodontology,
University of Regensburg, cency”; Esthetic anatomical form”; “Fracture of material
Regensburg, Germany and retention”; “Marginal adaptation”; “Recurrence of
caries, erosion, abfraction”; and “Tooth integrity (enamel
R. Randall cracks, tooth fractures)”. Typical clinical cases are
3M ESPE Dental,
St. Paul, MN, USA presented for each of these eight criteria and their
corresponding five scores.
G. Vanherle
K.U. Leuven,
Leuven, Belgium Keywords Study . e-calib . Calibration . Composite
350 Clin Oral Invest (2010) 14:349–366

Introduction four of the authors of this paper for the e-calib program (see
below), some minor shortcomings of the criteria as
In 2007, new clinical criteria for the evaluation of originally published became apparent. As mentioned in
restorations were published in the Journal of Adhesive the original publications, these criteria are a living
Dentistry [4] as well as Clinical Oral Investigations [3], and document which should be improved from time to time.
an extended abstract was published in the International The objectives of the present paper are three-fold:
Dental Journal [2]. The criteria and the grading were
1. Presentation of the changes and improvements that
approved by the Science Committee of the FDI World
have been made to the criteria since 2007
Dental Federation in 2007 and in the General Assembly
2. Presentation of clinical cases that should serve as
2008 as “standard criteria” that should be applied when
illustrative examples for most of the criteria
restorative materials and/or operative techniques are to be
3. Short presentation of a web-based training and calibra-
clinically investigated. Likewise, the criteria should be
tion tool (www.e-calib.info).
applied when patients are recruited for clinical trials to
evaluate a new restorative material or operative technique,
and the criteria for the replacement of old restorations by
new restorations should be the same as for the evaluation of e-calib
the replaced restorations. Furthermore, the clinical evalua-
tion of restorations may be necessary and useful for quality
assessment of restorations that are placed by general
practitioners in their own practices. In addition the future
dental students should be trained to use these criteria as part
of a clinical examination to determine whether a restoration
can be maintained or whether it needs refurbishment, repair In the past, evaluators were trained and calibrated with
or replacement. photographs and slides [5]. In 2006, an online calibration
The FDI criteria have been applied by several inves- system using USPHS criteria has been installed at the
tigators since then; however, results have been only partly University of Michigan (www.dent.umich.edu/CER/) and
published so far. Some short-term results were published as was mentioned in the earlier publications [3, 4]. In July
abstracts at the International Association for Dental 2008, a tool called ‘e-calib’ (electronic calibration) was put on
Research (IADR) meetings [1, 6, 7]. One study compared the World Wide Web to facilitate both training and calibration
the FDI criteria and the traditional United States Public of the new FDI criteria. The tool is based on the program
Health Service (USPHS; also known as ‘Ryge criteria’) “moodle” (www.moodle.com) and can be accessed via www.
criteria for the evaluation of restorations in deciduous teeth e-calib.info, located at the University of Munich (Firefox or
[6]. The authors concluded that the new FDI method was Safari browsers are preferred; the XML Viewer has to be
more sensitive for identifying differences in deciduous installed when Microsoft Internet Explorer is used). Use of the
composite resin restorations. tool is free of charge; but anyone interested in the tool have to
It must be emphasized that the clinical relevance of the register and will receive an individual profile. One can train on
defined cut off values for subscores that are included in a specific criterion or train all criteria on illustrated clinical
some of the criteria has yet to be verified in longitudinal cases. The cases are selected randomly from a database and
clinical trials. Quantitative values are given for the width of only high-quality photographs are included. The answers
marginal gaps, the tightness of approximal contact points given by the participant are checked by the system to see
and the amount of clinical wear. whether they match the grading given by a panel of four
It must also be stressed that many (ongoing) clinical experts (see below). After completion of the clinical cases, the
studies still will use the USPHS criteria, and if they have participant receives a report of the percentage of correct
begun the study with these criteria, they shall continue to answers and can repeat the procedure to find areas of
use them for the entire period of the trial. agreement and disagreement. Color-coded arrows and circles
Since the publication of the FDI criteria, one workshop point to and highlight special items such as marginal
and two symposia have been held at international meetings discrepancies, marginal staining, enamel cracks or voids in
to introduce and explain the new clinical criteria: IADR in the material. Different colors are used for the different criteria
Toronto (2008), IADR in Miami (2009) and ConsEuro in as one may train on all criteria on the same restoration.
Seville (2009). Numerous clinical cases were shown and Alternatively, training can be done on a specific criterion on
the grading discussed with the audience. During these several clinical cases. Each training course is saved under the
meetings and also during the evaluation and grading of participant’s individual profile and cannot be accessed by
clinical cases by means of occlusal images, performed by other participants or by the program administrators.
Clin Oral Invest (2010) 14:349–366 351

e-calib does not replace calibration of evaluation criteria The objectives of e-calib are:
on patients in a clinical setting, but may shorten the clinical
– to efficiently train and calibrate clinical dental research
calibration significantly. Special criteria such as evaluation
workers using e-learning features
of approximal contact areas, approximal excess of material
– to reduce the variability of the outcome of clinical trials on
and the periodontal or mucosal response to restorations can
dental restorations using standardized assessment criteria
only be trained and calibrated on patients (Table 1).
– to better compare the results of clinical trials on dental
Furthermore, for verification of special clinical phenomena
restorations between different centres in the world
such as marginal gaps, dental instruments (e.g. probes) are
– to render clinical calibration programs more efficient
necessary and may potentially cause damage. However, if
– to improve student teaching
research workers use e-calib to train themselves, clinical
– to improve daily clinical practice
calibration programs may be less time-consuming and more
– to be used as a tool in the teaching at dental schools
efficient. We recommend that international calibration
sessions and workshops should be held continuously at e-calib will expand over time. Up to now, about 300 clinical
dental conferences and symposia not only with clinical cases of posterior approximal and occlusal resin composite and
pictures but also with restored extracted teeth. Web-based ceramic inlays/onlays are included into the database. In the
calibration programs, workshops and calibration courses on future, carious and non-carious cervical restorations, approx-
patients shall not only train the new criteria but shall also imal anterior restorations and incisal edge restorations will be
reduce the risk for premature replacement of restorations put into the database. Amalgam and gold restorations will also
both in clinical trials and at dental faculties (e.g. student be included as in many clinical trials, amalgam is replaced by
training courses). resin composite without applying standardized criteria for
The cases were selected by four experienced clinicians amalgam replacement. Furthermore, there are still some
(R. Hickel, J.-F. Roulet, S.D. Heintze, A. Peschke) who randomized clinical trials which use amalgam as the ‘control’
agreed on each criterion for each case that was presented as or ‘comparison’ material.
a clinical picture. However, other clinicians may judge a
restoration differently. There is a certain degree of
subjectivity within each clinical assessment, and the chosen Criteria
scores may be altered in e-calib if strong arguments are put
forward by users. e-calib should be seen as an open forum The evaluation of a restoration is categorized into three groups:
to which everybody can contribute with comments and also esthetic, functional and biological criteria. Each group has
clinical pictures. subcategories, and the overall rating is determined by the

Table 1 The following criteria cannot be trained and calibrated by pictures of the occlusal aspect of posterior restorations:

II Functional properties

7. Wear Wear can only be reliably and correctly evaluated quantitatively on replicas such as 3D laser
scanning and is recommended to do on replicas with an adequate scanning device and
software. But also qualitative wear rating is of very limited on pictures.
8. Contact point/food impact Approximal contact points have to be clinically evaluated with metal blades of standardized
thicknesses (or less precisely with dental floss).
9. Radiographic examination This criterion requires X-rays which will be added to the program in a later step.
10. Patient’s view This criterion requires the need of a structured interview with the patient on his/her
satisfaction/dissatisfaction with the restoration.

III Biological properties

11. Postoperative (hyper-)sensitivity This criterion can only be evaluated on the patient by means of a stimulus (e.g. by a blast of
and tooth vitality cold air or by dry ice).
14. Periodontal response This criterion can only be evaluated on the patient by means of a periodontal probe and by
comparing the reaction of the gingival tissues of the restored tooth and a control tooth.
15. Adjacent mucosa This criterion can only be evaluated on the patient as a broad clinical inspection of the
mucosa in the oral cavity is necessary.
16. Oral and general health This criterion requires the need of a broad clinical inspection of the whole oral cavity and
also the medical status and history of the patient.
352 Clin Oral Invest (2010) 14:349–366

subcategory scores, with the final score in each group being requires repair should be considered as a (relative) failure.
dictated by the most severe score among all the subscores. For Repaired restorations should be monitored and evaluated as an
example, if one property/category is unacceptable, the final, integral part of the restoration.
overall score of this restoration is also unacceptable. Therefore, To take into consideration the extent of a clinical defect
when summarizing the three categories (esthetic, functional or observation in relation to the entire restoration or to
and biological) in one overall rating, the worst score prevails record the exact location of the defect, the SQUACE
and gives the final score. method (SemiQUAntitative Clinical Evaluation) is recom-
If a parameter is judged to be clinically unacceptable, mended [3, 4]. This is especially valuable for the criteria
then the exact reason for failure has to be recorded, and it “marginal staining” (2.b), “fracture of material” (5),
must be decided whether the restoration can be repaired or “marginal adaptation” (6) and “CAR” (12).
requires replacement. Not all ‘failures’ lead to replacement The overall rating for a particular restoration is deter-
of a restoration. Localized defects with sufficient clinical mined after completion of the assessments of the final
access can be repaired, e.g. sealing of gaps, adding new scores for esthetic, functional and biological properties. The
material to chipping fractures, partial removal and veneer- most severe score will prevail. A description of the criteria
ing of stained areas of the restorations, etc. and grading is presented in table 2. Whenever a restoration
Repaired restorations are therefore scored as “relative receives a score of 4 or 5 independent of the specific
failure” and replaced restorations as “absolute failure”. criteria below, it must be recorded as a failure, but not all
The decisive difference between scores 4 and 5 is not the failures call for replacement of the entire restoration.
need for an immediate or a later (some weeks) replacement A simplified clinical evaluation may be appropriate for a
of the restoration; but rather whether the restoration can be variety of reasons, e.g. it is possible to pool scores 1 and 2
corrected/repaired or whether it has to be replaced (equivalent to USPHS/Ryge score A), resulting in four
completely. Most frequently, score 5 will show worse different scores (two acceptable and two unacceptable), or
clinical results than score 4, but that is not inevitable. Score even to combine scores 1, 2 and 3 to only one acceptable
4, and consequently the possibility for repair, depends more score and additionally two or one (merged scores 4 and 5)
on the location and size of the defect and therefore whether unacceptable score.
it is accessible for repair or not. Furthermore, there is no need to apply all of the 16 criteria in
Some examples of conditions suitable for repair are: each study. Before starting a clinical study, the primary and
secondary goals have to be defined and the investigator has to
– Large marginal opening (>250 µm), or severe staining
determine which criteria should be used for the intended
which is esthetically unacceptable, or secondary caries
purpose. If, for example, a new esthetic resin composite material
without deep undermining caries, if accessible
is to be evaluated, special emphasis should be put on the criteria
– Selective marginal preparation in the case of “caries
that comprise the esthetic category. On the other hand, if a
adjacent to restorations” (CAR) or replacement of only
material that has only one shade for use in non-visible areas (e.g.
one approximal box of an MOD restoration if cervical
molars), the criterion “color match” can be dropped as esthetic
caries is present
issues are of low interest compared with anterior restorations.
– Chipping/partial fracture or marginal fracture of restorative
material (repaired by incremental addition of material)
– Marginal breakdown of enamel or minor/localized cusp
Changes and improvements of criteria since 2007
fracture (repaired by incremental addition of material)
– Filling of access cavity after endodontic treatment
In the following, only the criteria that have been modified
– Amalgam restorations with accessible defects which
since the 2007 publication are presented and explained.
can be repaired using adhesive techniques, such as
Photographs for the scores of each criterion are only
bonded amalgam or composite
provided for those criteria that can be trained with the e-
– Ceramic inlays or partial crowns with fractures and/or
calib tool. If the criterion can be trained with e-calib, it is
chipping which may be repaired by intraoral sand-
mentioned in parenthesis. The reasons for the other criteria
blasting/silication, silanization and composite bonding
not being included are listed in table 1.
A repair is a minimally invasive approach that implies the
A. Esthetic properties
addition of restorative material after the defect is explored and
determined not to be invasive with or without preparation in the
material and/or dental hard tissues. Refurbishment is defined as 1. Surface gloss/lustre and roughness (e-calib)
a minimal intervention such as contouring or polishing or the The subscores ‘isolated pores’ (1.2.2) and ‘multiple pores’
application of glaze or adhesives with no new restorative (1.3.2) have been added as these phenomena cannot only be
material added. Based on these definitions, a restoration that described by a dull surface but can also affect the texture of the
Table 2 FDI criteria and gradings
Clinical investigation ……………………………………..
ID patient / restoration ……………………………………..
Date (dd /mm/yy): Baseline……………. 1. Recall ………….. 2. Recall………… 3. Recall………… 4. Recall……....... 5.
Recall………...
Photographs (n˚ and date) : …………………… …
Replica (n˚ and date): ……………………….
1. Surface lustre 2. Staining 3. Color match and 4. Esthetic
A. Esthetic properties
a. surface b. margin translucency anatomical form
1. Clinically excellent / very 1.1 Lustre 2a.1 No surface staining. 3.1 Good color match, no 4.1 Form is ideal.
good comparable to 2b.1 No marginal staining. difference in shade and/or
Clin Oral Invest (2010) 14:349–366

enamel. translucency.
2. Clinically good 1.2.1 Slightly dull, not 2a.2 Minor surface staining, easily 3.2 Minor deviations 4.2 Form is only slightly
(after polishing probably very noticeable from speaking removable by polishing. in shade and/or deviated from the normal.
good) distance. 2b.2 Minor marginal staining, easily translucency
1.2.2 Some isolated pores. removable by polishing.
3. Clinically sufficient / 1.3.1 Dull surface but 2a.3 Moderate surface staining that 3.3 Distinct deviation but 4.3 Form deviates from
satisfactory acceptable if covered with may also present on other teeth, not acceptable. Does not affect the normal but is
(minor shortcomings, no film of saliva. esthetically unacceptable. esthetics: esthetically acceptable.
unacceptable effects but not 1.3.2 Multiple pores on more 2b.3 Moderate marginal staining, not 3.3.1 more opaque
adjustable w/o damage to the than one third of the surface. esthetically unacceptable. 3.3.2 more translucent
tooth) 3.3.3 darker
3.3.4 brighter
4. Clinically unsatisfactory 1.4.1 Rough surface, cannot 2a.4 Unacceptable surface staining 3.4 Localized clinically 4.4. Form is affected and
(but reparable) be masked by saliva film, on the restoration and major deviation that can be unacceptable
simple polishing is not intervention necessary for corrected by repair: esthetically.
sufficient. Further improvement. 3.4.1 too opaque. Intervention/correction is
intervention necessary. 2b.4 Pronounced marginal staining; 3.4.2 too translucent. necessary.
1.4.2 Voids. major intervention necessary for 3.4.3 too dark.
improvement. 3.4.4 too bright.
5. Clinically poor 1.5 Very rough, 2a.5 Severe surface staining and/or 3.5 Unacceptable. 4.5 Form is unsatisfactory
(replacement necessary) unacceptable plaque subsurface staining, generalized or Replacement necessary. and/or lost. Repair not
retentive surface. localized, not accessible for feasible / reasonable,
intervention. Replacement needed.
2b.5 Deep marginal staining, not
accessible for intervention.

Overall esthetic score Acceptable esthetically (n and %): Not acceptable (n, % and reasons):
353
Table 2 (continued)
354

5. Fracture of 6. Marginal 7. Occlusal 8. Approximal 9. Radiographic 10. Patient’s view

B. Functional material and adaptation contour and wear anatomical form examination
properties retention a) qualitatively a. contact point (when applicable)
b) quantitatively b. contour
1. Clinically 5.1 No fractures / 6.1 Harmonious 7a.1 Physiological 8a.1 Normal 9.1 No pathology, 10.1 Entirely
excellent / very cracks. outline, no gaps, no wear equivalent of contact point (floss harmonious satisfied with
good white or enamel. or 25 µm metal transition between esthetics and
discolored lines 7b.1Wear blade can pass) restoration and function.
corresponding to 8b.1 Normal tooth.
80-120% of contour.
enamel.
2. Clinically good 5.2 Small hairline 6.2.1 Marginal gap 7a.2 Normal wear 8a.2. Contact 9.2.1 Acceptable 10.2 Satisfied.
crack. (<150 µm), white only slightly slightly too strong material excess 10.2.1 Esthetics.
lines. different from that but no present. 10.2.2 Function, e.g.,
6.2.2 Small to enamel. disadvantage (floss 9.2.2 minor roughness
marginal fracture 7b.2 50-80% or or 25 µm metal Positive/negative
removable by 120-150 % wear blade can only step present at
polishing. compared to that of pass with margin <150 µm.
6.2.3 Slight corresponding pressure).
ditching, slight enamel. 8b.2 Slightly
step/flashes, minor deficient contour.
irregularities.
3. Clinically 5.3 Two or more or 6.3.1 Gap < 250 7a.3 Different wear 8a.3. Somewhat 9. 3. 1 Marginal gap 10.3 Minor criticism
sufficient / larger hairline µm not removable. rate than enamel but weak contact, no < 250 µm. but no adverse
satisfactory cracks and/or 6.3.2. Several small within the biological indication of 9. 3. 2 Negative clinical effects.
(minor material chip marginal fractures. variation. damage to tooth, steps visible < 250 10.3.1 Esthetic
shortcomings, no fracture not 6.3.3 Major 7b.3 < 50 % or 150- gingiva or µm. shortcomings.
unacceptable affecting the irregularities, 300 % of periodontal No adverse effects 10.3.2 Some lack of
effects but not marginal integrity or ditching or flash, corresponding structures; 50 µm noticed. chewing comfort.
adjustable w/o approximal contact. steps. enamel metal blade can 9.3.3 Poor 10.3.3 Unpleasant
damage to pass radiopacity of filling treatment procedure.
the tooth) 8b.3 Visible material.
deficient contour
4. Clinically 5.4.1 Material chip 6.4.1 Gap > 250 7a.4 Wear 8a.4 Too weak and 9.4.1 Marginal gap 10.4 Desire for
unsatisfactory / fractures which µm or dentine/base considerably possible damage >250 µm. improvement
(but reparable) damage marginal exposed. exceeds normal due to food 9.4.2 Material 10.4.1 Esthetics.
quality or 6.4.2. Severe enamel wear; or impaction; excess accessible 10.4.2 Function, e.g.,
approximal ditching or marginal occlusal contact 100 µm metal blade but not removable. tongue irritation
contacts. fractures. points are lost. can pass 9.4.3 Negative steps Reshaping of
5.4.2 Bulk fractures 6.4.3 Larger 7b.4 Restoration > 8b.4 Inadequate >250µm and anatomic form or
with partial loss irregularities or 300 % of enamel contour reparable. refurbishing is
(less than half of steps (repair wear or antagonist Repair possible. possible.
the restoration). necessary) > 300 %.
Clin Oral Invest (2010) 14:349–366
5. Clinically poor 5.5 (Partial or 6.5.1 Restoration 7a.5 Wear is 8a.5 Too weak 9.5.1 Secondary 10.5 Completely
(replacement complete) loss of (complete or excessive. and/or clear caries, large gaps, dissatisfied and / or
necessary) restoration or partial) is loose but 7b.5 Restoration or damage due to large overhangs adverse effects, incl.
multiple fractures. in situ. antagonist > 500 % food impaction 9.5.2 Apical pain.
6.5.2 Generalized of corresponding and/or pathology
major gaps or enamel. pain/gingivitis. 9.5.3 Fracture/loss
irregularities. 8b.4 Insufficient of restoration or
contour requires tooth.
replacement
Overall functional
Acceptable function (n and %): Not acceptable (n, % and reasons):
Clin Oral Invest (2010) 14:349–366

score
11. Postoperative 12. Recurrence of 13. Tooth 14. Periodontal 15. Adjacent 16 Oral and general
(hyper-)sensitivity caries (CAR), integrity (enamel response mucosa health
C. Biological
and tooth vitality erosion, cracks, tooth (always compared
properties
abfraction fractures) to a reference
tooth)
1. Clinically very 11.1 No 12.1 No secondary 13.1 Complete 14.1. No plaque, no 15.1 Healthy 16.1 No oral or
good hypersensitivity, or primary caries integrity. inflammation, no mucosa adjacent to general symptoms.
normal vitality. pockets. restoration.
2. Clinically good 11.2 Minor 12.2 Small and 13.2.1 Small 14.2. Little plaque, 15.2 Healthy after 16.2 Minor transient
(after correction hypersensitivity for a localized marginal enamel no inflammation minor removal of symptoms of short
maybe very limited period of time, 1. Demineralization fracture (<150 (gingivitis), no mechanical duration; local or
good) normal vitality. 2. Erosion or µm). pocket irritations (plaque, generalized.
No treatment 3. Abfraction. 13.2.2 Hairline development calculus, sharp
required. crack in enamel 14.2.1 without edges etc.)
(<150 µm). 14.2.2 with
overhangs, gaps or
inadequate
anatomic. form
3.Clinically 11.3.1 Moderate 12.3 Larger areas 13.3.1 Marginal 14.3. Difference up 15.3 Alteration of 16.3. Transient
sufficient / hypersensitivity of 1. enamel defect to one grade in mucosa but no symptoms, local
satisfactory 11.3.2 Delayed/mild Demineralisation <250µm severity of PBI suspicion of causal and/or general.
(minor shortcomings sensitivity; no 2. Erosion or 13.3.2 Crack compared to relationship with
with no adverse subjective 3. Abrasion/abfracti <250µm; baseline and restorative
effects but not complaints, no on, dentine not 13.3.3 Enamel compared to material.
adjustable without treatment needed. exposed Only chipping. control tooth.
damage to the tooth) preventive 13.3.4 Multiple 14.3.1 without
measures cracks 14.3.2 with
necessary (). overhangs, gaps or
inadequate
anatomic form.
355
Table 2 (continued)
356

4. Clinically 11.4.1 Intense 12. 4.1 Caries with 13.4.1 Major 14.4. Difference of 15.4 Suspected 16.4 Persisting local
unsatisfactory hypersensitivity. cavitation and marginal enamel more than one mild allergic, or general symptoms
(repair for 11.4.2 Delayed with suspected defects; gap > 250 grade of PBI in lichenoid or toxic of oral contact
prophylactic minor subjective undermining caries µm or dentine or comparison to reaction. stomatitis or lichen
reasons) symptoms. 12.4.2 Erosion in base exposed. control tooth or planus or allergic
11.4.3 No clinical dentine 13.4.2 Large increase in pocket reactions.
detectable sensitivity. 12.4.3 Abrasion/ cracks >250 µm, depth > 1mm Intervention
abfraction in probe penetrates. requiring necessary but no
Intervention dentine. 13.4.3. Large intervention. replacement.
necessary Localized and enamel chipping 14.4.1 without
but not replacement. accessible can be or wall fracture 14.4.2 with
repaired. overhangs, gaps or
inadequate
anatomic form
5. Clinically poor 11.5 Intense, acute 12.5 Deep 13.5. Cusp or 14.5 Severe / acute 15.5 Suspected 16.5. Acute / severe
(replacement pulpitis or non vital caries or exposed tooth fracture. gingivitis or severe allergic, local and/or general
necessary) tooth. Endodontic dentine that is not periodontitis lichenoid or toxic symptoms.
treatment is accessible for 14.5.1 without reaction.
necessary and repair of 14.5.2 with
restoration has to be restoration. overhangs, gaps or
replaced. inadequate
anatomic form

Overall biological
Acceptable biologically (n and %): Not acceptable (n, % and reasons):
score
Clin Oral Invest (2010) 14:349–366
Clin Oral Invest (2010) 14:349–366 357

surface. It has to be stressed again that the quality of surface multiple fractures may be reparable, but practically, it may not
lustre and roughness can only be adequately evaluated if the be appropriate to do so. Marginal fractures should not be
restored tooth has been thoroughly cleaned and dried. confused with flashes and overhangs, and the latter shall be
evaluated under the criterion “marginal adaptation”.
2. Surface and marginal staining (e-calib)
6. Marginal adaptation (e-calib)
In the original publication, marginal staining and surface
staining comprised one single criterion, the rationale being Marginal gaps
that both phenomena affect the esthetic appearance of a
In the original publications from 2007 [3, 4], the relation-
restoration. However, when evaluating clinical pictures for the
ship between microleakage, marginal gaps and secondary
e-calib program, it soon became apparent to the four
caries (caries adjacent to restorations CAR) was extensively
evaluators that these phenomena had to be differentiated and
covered. In clinical studies, the parameter “microleakage”
evaluated separately. Marginal staining can depend on the
shall not be used as it does not cause caries (CAR).
effectiveness of dentin/enamel bonding agent systems, as well
Microleakage is associated with dye penetration, and the
as on the operative technique or physical parameters of the
term should be reserved for in vitro studies only. To obtain
restorative material, whereas surface staining depends more
better quality data for clinical prediction of for instance
on the properties of the material to retain pigments from the
marginal staining or caries adjacent to restorations, restora-
oral environment. Therefore, the criterion has been divided
tion gap width should be classified. To classify the marginal
into ‘surface staining’ (a) and ‘marginal staining’ (b).
gaps, two special probes (Deppeler, Switzerland) are
Marginal staining is primarily a staining of the contents of a
available with tip diameters of 150 and 250 µm. The depth
crevice between the cavity wall and the restoration, subse-
of the gap should be at least the same size (0.25 mm). The
quently affecting the margins of the restoration. Surface
use a sharp explorer for gap or caries detection is not
staining of a restoration is due to a material deficiency or
recommended. Debonding may lead to a loose filling which
inadequate finishing/polishing of the restoration. If staining is
requires replacement. However, also major generalized
of special interest, it is recommended to ask the subject with
marginal gaps and irregularities may justify replacement
regard to his diet and smoking habits.
of the entire restoration.
3. Color match and translucency (e-calib)
7. Occlusal contour and wear
The term color stability has been changed to color match as it is
clinically more important, and a clinical observation of minor The term “occlusal contour” has been added to this criterion,
color changes is impossible to measure correctly over a period of since the alteration of occlusal contour during the service time
several years as it may change over time and also tooth color of the restoration can be a sign of material degradation or
may change. Further, subscores (‘too opaque/translucent/dark/ wear. Wear can be assessed qualitatively by the evaluator or
bright’) have been added. These subscores are optional and may quantitatively on replicas with special sensors and computer
be ignored, if appropriate. software. In both instances, baseline and follow-up images/
replicas are needed in order to assess possible alterations.
4. Esthetic anatomical form (e-calib) Therefore, the criterion has been divided into “qualitatively”
It has become evident during the use of these criteria that (a) and “quantitatively” (b) measured wear.
anatomical deficiencies which impair the function, e.g. poor 8. Approximal contact point and food impaction
approximal contact and the effect on periodontal tissues,
should be dealt with in the respective sections (criteria 8 and The ‘tightness’ of the approximal contact area can be evaluated
14). Only restorations or parts of restorations that are easily with metal strips of three different thicknesses (25, 50 and
visible at a speaking distance or during wide mouth opening 100 µm) which are commercially available (Deppeler). If using
should be assessed, including incisal edge and anterior floss, the same type of floss has to be used for calibration at
approximal restorations that involve the labial surface, baseline and at all recalls.
cervical restorations in anterior teeth and premolars, and The approximal contact may be present, but the
large facial extensions of MO or MOD premolar restorations. approximal contour can be deficient, leading to plaque
accumulation and initial or secondary caries. If the
B. Functional properties
inadequate contour results in damage to the periodontal
tissues, this should be rated under criterion 14. However, an
5. Fracture of restorative material and restoration retention
inadequate contour can also affect the occlusal surface and
(e-calib)
should then be reflected under criterion 7b.
The term “multiple marginal material fractures” was added to Food impaction related to open contacts and/or an
score 5 (“replacement of restoration”) as a restoration with inappropriate shape of the approximal part of the restoration
358 Clin Oral Invest (2010) 14:349–366

should be recorded. Therefore, this criterion has now two clinical cases for the citerion “Staining” cannot be presented for
different subgroups: all scores of the two subgradings “Surface” and Margin. In
some figures, arrows and circles are used to point to the specific
(a) approximal contact area
characteristic of the restoration. These tools with the same
(b) approximal contour
colors are used in the e-calib program. (Figs. 1, 2, 3, 4 5 6, 7,
9. Radiographic examination
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
Ideally, the restorative material under test should have an 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39 and
adequate level of radiopacity. Care has to be taken if there 40).
is a thick layer of adhesive, which does not have adequate
radiopacity, that it may be misinterpreted as caries adjacent
to restorations (CAR). Summary and conclusions
9. Patient’s view
The 16 “FDI clinical criteria” for the evaluation of direct
The patient may complain about the restoration with regard to and indirect restorations were first published in 2007 and
its esthetic appearance and/or function. Therefore, this criterion have since been applied by several investigators in
has been divided into the two subscores “Esthetics” and clinical studies on resin composite restorations in
“Function”. For example, a rough restoration surface can annoy posterior teeth. The response was positive. The experi-
or even irritate the tongue of the patient and may therefore be a ence of the application of these criteria to clinical cases
matter of complaint. has made it reasonable to modify some of the criteria
and scores.
C. Biological properties
A clinical investigator planning a clinical study on direct
12. Recurrence of initial pathology (e-calib) and monitor- or indirect restorations must formulate hypotheses and
ing of progression define the purpose of the study as well as the primary and
The scores have been expanded with regard to caries secondary outcomes. Based on these considerations, the
adjacent to restorations (CAR), erosion and abfraction to investigator selects the clinical criteria which are necessary
better differentiate between pathology of different to accomplish the objective of the trial. Therefore, in many
Etiologies. instances, only some of the defined criteria are needed.
Furthermore, the five scores can be reduced to four or even
13. Tooth cracks and fractures (e-calib) two, depending on the purpose of the study and the type of
“Enamel chipping” and “multiple cracks” have been added to material or the operative/restorative procedure being tested.
score 13.3. Cracks that were present before a primary caries is It is mandatory that the investigators be trained and
restoratively treated or an insufficient restoration is replaced calibrated on these criteria, which is a prerequisite to
should be recorded at baseline before placement. Enamel compare the results of different studies. Training on some
cracks can occur in the vicinity of the restorative margin of the criteria can be adequately carried out using high-
(mainly at the proximal margins of Class II restorations) or quality clinical images of restorations. An interactive tool,
independent of the restoration margins at different locations. ‘e-calib’, is available on the Internet for that purpose. The
database contains several hundred clinical cases that are
14. Effect of the restoration on the periodontium representative of the five scores of eight criteria. Clinical
As restoration overhangs, gaps or inadequate approximal investigators are requested to use the tool to better
anatomical form can cause or enhance gingival inflam- standardize their clinical judgement on restorations and to
mation, this criterion has been expanded as to whether give feedback to the authors. The FDI criteria are not fixed
the inflammation is in conjunction with these approximal and defined. If good documentation can be presented,
restoration deficiencies. modifications and/or alterations are possible. Deviations
from the outlined criteria in publications should be justified
and illustrated Moreover, the proposed score for a specific
Figures of clinical examples clinical case may be challenged by other investigators.
Clinical investigators are therefore asked to send their
The criteria with their scores are listed directly after the Figure comments on specific scores to the authors. Furthermore,
number. If the score can be differentiated into a subscore, it is clinical investigators are welcomed and encouraged to
indicated in brackets after the description of the criterion that provide high quality pictures of clinical cases that can be
illustrates the clinical pictures in this edition of the journal, uploaded into the database.
Clin Oral Invest (2010) 14:349–366 359

Fig. 1 1.1: Lustre comparable to enamel

Fig. 4 1.4: Rough surface (1.4.1)

Fig. 2 1.2: Slightly dull, not noticeable from speaking distance (1.2.1)
Fig. 5 1.5: Moderately rough

Fig. 3 1.3: Dull surface but acceptable if covered with film of saliva (1.3.1) Fig. 6 2.1: No surface staining (2a.1, 2b.1)
360 Clin Oral Invest (2010) 14:349–366

Fig. 7 2.2: Minor surface staining (2a.2), minor marginal staining

(2b.2, see arrow) Fig. 10 2.5: Severe surface staining (2a.5) and deep marginal staining (2b.5)

Fig. 8 2.3: Moderate surface staining (2a.3, see circle) and moderate
marginal staining (2b.3, see arrow)

Fig. 9 2.4: Moderate surface staining (2a.3) and pronounced marginal

staining (2b.4, see arrows) Fig. 11 3.1: Good color match
Clin Oral Invest (2010) 14:349–366 361

Fig. 12 3.2: Minor deviation in color match Fig. 15 3.5: Unacceptable color match

Fig. 13 3.3: Clear deviation in color match (3.3.1 more opaque)

Fig. 16 4.1: Form is ideal

Fig. 14 3.4: Unsatisfactory/inadequate color match (3.4.3, too dark) Fig. 17 4.2: Form is only slightly affected
362 Clin Oral Invest (2010) 14:349–366

Fig. 21 5.1: No fractures/cracks

Fig. 18 4.3: Form is not ideal but is not esthetically displeasing

Fig. 19 4.4: Form is affected and unacceptable esthetically

Fig. 20 4.5: Form is unsatisfactory and/or missing Fig. 22 5.2: Small ‘hairline’ cracks
Clin Oral Invest (2010) 14:349–366 363

Fig. 23 5.3: Hairline crack (left arrow) and material chip fracture Fig. 26 6.1: Harmonious outline, no gaps, no white or discolored
(right arrow) lines

Fig. 24 5.4: Bulk fracture with partial loss of restorative material Fig. 27 6.2: Marginal gap (<150 µm), white lines (6.2.1)
(5.4.1, see arrow)

Fig. 25 5.5: Multiple fractures Fig. 28 6.3: Major irregularities and steps (6.3.3)
364 Clin Oral Invest (2010) 14:349–366

Fig. 32 12.2: Small and localized demineralization (12.2.1, see arrow)

Fig. 29 6.4: Severe ditching or marginal fractures (6.4.2)

Fig. 30 6.5: Filling is loose but in situ (6.5.1)

Fig. 31 12.1: No secondary or primary caries Fig. 33 12.3: Large areas of demineralisation (12.3.1, see arrow)
Clin Oral Invest (2010) 14:349–366 365

Fig. 36 13.1: Complete integrity

Fig. 34 12.4: Caries with suspected undermining caries (12.4.1, see

arrow)

Fig. 37 13.2: Hairline crack in enamel (13.2.2, see arrow)

Fig. 35 12.5: Deep caries and exposed dentine (see arrow) Fig. 38 13.3: Enamel chipping (13.3.3, see arrow)
366 Clin Oral Invest (2010) 14:349–366

Clinical relevance

The FDI clinical criteria and scoring system for the

evaluation of direct and indirect restorations are well
structures and flexible criteria which can be selected and
adjusted according to the needs of the investigator. After
training and calibration they can be applied not only by the
researchers but also by dental students and general
practitioners for quality assurance purpose e.g. to avoid
premature replacement and restorations. A web-based
training and calibration tool (e-calib) helps to spread the
information and to facilitate the training and calibration.)

Conflict of interests The authors declare that they have no conflict

of interest.

References
Fig. 39 13.4: Large enamel chipping (13.4.3, see arrow)

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