Quantitative measures of gingival recession and the influence of gender, race, and attrition
Handelman et al. Progress in Orthodontics
Quantitative measures of gingival recession and the influence of gender, race, and attrition
Chester S. Handelman 0
Anthony P. Eltink 0
Ellen BeGole 0
0 Department of Orthodontics, College of Dentistry, University of Illinois at Chicago , Chicago, IL , USA
Background: Gingival recession in dentitions with otherwise healthy periodontium is a common occurrence in adults. Recession is clinically measured using a periodontal probe to the nearest millimeter. The aim of this study is to establish quantitative measures of recession, the clinical crown height, and a new measure the gingival margin-papillae measurement. The latter is seen as the shortest apico-coronal distance measured from the depth of the gingival margin to a line connecting the tips of the two adjacent papillae. Methods: Measurements on all teeth up to and including the first molar were performed on pretreatment study models of 120 adult Caucasian and African-American subjects divided into four groups of 30 by gender and race. Results: Both the clinical crown height and the gingival margin-papillae measurements gave a true positive result for changes associated with gingival recession. Tooth wear shortens the clinical crown, and therefore, the measure of clinical crown height can give a false negative result when gingival recession is present. However, the gingival margin-papillae measurement was not affected by tooth wear and gave a true positive result for gingival recession. Tooth wear (attrition) was not associated with an increase in gingival recession. These measures are also useful in detecting recession prior to cemental exposure. Measures for recession and tooth wear were different for the four demographic groups studied. Conclusions: These measures can be used as quantitative standards in both clinical dentistry, research, and epidemiological studies.
Gingival recession; Gingival recession measures; Attrition; Gingival architecture; Cementum exposure; Clinical crown height
Gingival recession is observed in adults otherwise free of
periodontal disease with a high standard of oral hygiene
]. Recession is of concern to patients who view the loss
of attachment as a health issue as well as an esthetic
problem. The intent of this paper is to establish
quantitative measures of the gingival margin position in four
groups: Caucasian and African-American males and
females that were otherwise free of periodontal disease.
The measures evaluated are clinical recession, clinical
crown height, and a new measure the gingival
marginpapillae measurement. The influence of dental attrition
on these measures was also evaluated.
While researchers in periodontics have looked to
understand the biology of the periodontium [
fields of esthetic dentistry and orthodontics have been
concerned with the role that gingival architecture plays
in dental esthetics [
In health, the shape of the papilla in a given interdental
space depends on the contact point between the two
adjoining teeth [
]. In the absence of interproximal bone
loss, the gingival papilla completely fills the gingival
]. As stated by Löe et al. [
] and Newman et al.
], the gingival margin’s position in the healthy
periodontium is 0.5 to 2.0 mm coronal to the cemento-enamel
junction. As the cemento-enamel junction of the tooth
curves apically from its more coronal interdental position,
the gingival margin follows this curvature, creating the
characteristic scalloping contour of healthy gingiva.
Age-related gingival recession observed in some
subjects results in changes in the gingival architecture that
can be distinguished from changes resulting from
periodontal disease [
1, 9, 10
]. In cases of gingival recession
that occurs in the absence of gingivitis or periodontitis,
the papillae maintain its normal position while the
curvature of the gingival margin on the facial aspect of
the tooth deepens [
Gingival recession is measured clinically as the distance
from the cemento-enamel junction to the depth of the
free gingival margin using the millimeter markings on the
periodontal probe and reflects exposure of the root
]. While this clinical recession measurement
is useful in following the progression of gingival recession,
it has two shortcomings. First, it is semi-quantitative with
precision to 0.5 to 1.0 mm. Second, it is not an accurate
assessment of the apical migration of the gingival margin
due to its reliance on the cemento-enamel junction as a
reference point. Given that the gingival margin’s
physiological position may be 0.5 to 2.0 mm coronal to the
cemento-enamel junction [
], the reference point for
clinical recession is obscured by the gingiva itself. Thus,
the early stages of gingival recession prior to exposure of
the cementum—defined in this paper as prodromal
recession—might go undiagnosed.
Clinical crown height is a measure of the position of
the gingival margin that could be used in determining
the position of the gingival margin [
]. Powell and
] showed that the norms for clinical crown
heights are useful in the diagnosis of gingival recession.
The use of clinical crown height as a measure of
gingival recession is complicated by the wear at the incisal
edge or cusp tip. Attrition over time leads to a decrease
in the clinical crown heights of patient’s teeth and can
mask the presence of gingival recession if clinical crown
height is used as a measure. One may also question if
tooth wear which is usually attributed to bruxism plays a
role in gingival recession possibly due to abfraction.
Given the complexity of assessing gingival recession,
it can be proposed that a new measure of gingival
recession should be established which would allow
precise quantification of recession, one of the
shortcomings of clinical recession. Gorman [
and Kingman [
], and Löe et al. [
] found that
interproximal recession in the absence of periodontal
disease is rare and gingival recession occurs almost
exclusively on the buccal surfaces of teeth at the
depth of the gingival crest [
]. Thus, the shortest
apico-coronal distance measured from the depth of
the gingival margin to a line connecting the tips of
two adjacent papillae—the gingival margin-papillae
measurement—would serve as an accurate assessment
of gingival recession. Prodromal recession—recession
prior to cemental exposure would be detected, and enamel
attrition would not confound the measurements.
This retrospective study analyzed pretreatment study
models of adult patients from a private orthodontic
practice. In addition to study models, recording of
probing depths, full mouth dental x-rays, and intraoral
photographs were available on each subject. All records
were de-identified per the HIPAA regulations to ensure
that the patients could not be identified. This study was
performed under the guidance of the University of
Illinois at Chicago's Institutional Review Board, approval
The objective of the selection criteria was to establish a
group of subjects for the study of gingival recession that
occurs in persons with otherwise periodontally healthy
mouths. The study sample consisted of 120 patients
chosen serially so that the requisite number of 30
subjects was achieved in each of the four demographic
groups: Caucasian and African-American males and
The inclusion criteria were as follows:
1. Age of 20–59
2. No more than three areas of bone loss (3 mm or
more from the interproximal cemento-enamel
junction to the crest of the alveolus) evident on full
mouth radiographs and no more than three teeth
that had a pocket depth reading of 4 mm or more
3. No evidence of gingivitis as judged on intraoral
4. Individual teeth with radiographic evidence of
localized bone loss of 3 mm or more were excluded
5. Individual teeth with a pocket depth of 4 mm or
more were excluded
6. Teeth blocked out of the arch or adjacent
edentulous spaces were excluded
7. Fixed prosthodontic crown and fixed bridge
abutments were excluded
8. Teeth subject to frenum pull to the gingiva were
The number of subjects excluded because of criteria 1
to 3 was not recorded. Exclusion because of periodontal
bone loss or deep probing measures numbered about 25
subjects. Only a few subjects were excluded because of
The following data for each subject were recorded: age
in years, race, and gender. In order to evaluate subjects’
gingival health and cemental exposure, 35-mm film
slides of each subject’s buccal and anterior teeth were
mounted in a table viewer with × 5 magnification. Using
the intraoral photographs as an aid in identification of
the cemento-enamel junction , the following
measurements were made for each tooth on study models:
clinical recession, clinical crown height, gingival
marginpapillae, and attrition.
The data for clinical crown height and gingival
marginpapillae were measured and recorded using a Mitutoyo
Absolute Digimatic digital caliper (No. 99MAD014M, Series
No. 500; Mitutoyo American Corporation, Aurora, IL). An
input tool with a connecting cable (No. 99MAM014B1,
Series No. 264 and No. 959149; Mitutoyo American
Corporation, Aurora, IL) was used for the automatic
transfer of the data into the Microsoft Excel spreadsheet and
transferred to the Statistical Package for the Social Sciences
(SPSS, version 11.5; SPSS Inc., Chicago, IL).
Clinical recession was recorded on all teeth as the
shortest distance from the cemento-enamel junction to the
deepest curvature of the gingival margin (Fig. 1a). The
measurements were made to the nearest whole
millimeter using a standard periodontal probe, always
rounding up so that even minimal cemental exposure was
scored at 1 mm.
Clinical crown height was measured with digital
calipers to the nearest one hundredth of a millimeter on the
facial surface of each crown from the cusp tip or incisal
edge to the deepest curvature of the gingival margin
along the long axis of the tooth for bicuspid, cuspid, and
incisor teeth and on the molar teeth at the mesiobuccal
cusp (Fig. 1b).
The gingival margin-papillae measurements were
recorded using the digital calipers to the nearest one
hundredth of a millimeter as the shortest distance from
the interpapillae line to the deepest curvature of the
gingival margin (Fig. 1c). The measurements on molar teeth
were made at the mesiobuccal cusp.
Tooth wear was scored on the buccal of all teeth using
Hooper et al.’s tooth wear index [
]. Each tooth was
assigned a score from 0 to 5 according to the criteria
outlined by Hooper et al. (Fig. 2).
A power analysis using data from a previously published
] indicated that with a sample of at least 30
subjects in each group, the study has a power of at least
80%, (type error of 5%) to detect 1 standard deviation
mean difference between the groups.
Means and standard deviations of all measures were
established for each tooth class from the central incisors
to and including the first molars. Independent t-tests
show no significant difference between values for the
right and left sides for each tooth class so these values
were combined. Independent t-tests were used to
evaluate if differences existed between the subsets: the
recession and non-recession teeth and the tooth wear and
non-tooth wear teeth.
The age data for the study sample were analyzed to
determine if the four demographic groups differed with
respect to age. The results of the ANOVA comparison
Up to 1/3
1/3 to 2/3
> 2/3 Cusp
revealed that there was no difference in age among the
groups using p < 0.05. The mean age for the four groups
ranged from 33.2 to 39.2 years [
The accuracy of the four measurements was evaluated
in ten randomly selected cases. Study models were
measured and then re-measured 10 days later. Using the
Pearson correlations, all re-measured sets of values
showed a significant correlation at the 0.01 level. All
measurements and statistics were performed by one
Mean values and standard deviations for the
measurement of clinical crown heights for each tooth are listed
for the four demographic groups in Table 1. The mean
values and standard deviations for the measurement of
gingival margin-papillae are listed in Table 2. The overall
data set of 120 subjects (N = 1522 teeth) was separated
into two subsets on the basis of the clinical recession
measurement for each tooth. The first subset, called the
“non-recession teeth” (N = 1222 teeth), was comprised of
all teeth whose measurements were scored 0 mm for the
clinical recession measurement. The second subset,
called the “recession teeth” (N = 300 teeth), was
comprised of measurements on all teeth that were scored
1 mm or greater including teeth with minimal recession.
Independent t-tests were performed for clinical crown
height and gingival margin-papillae to determine
whether differences exist between these two subsets of
teeth for these measurements.
For clinical crown height, independent t-tests found
teeth with recession were significantly larger than the
clinical crown height measurement for the
nonrecession teeth (Table 3).
For gingival margin-papillae measure, teeth in the
recession subset were significantly larger than
nonrecession for all tooth classes except for the lower lateral
incisor (Table 4).
The overall data set (N = 1467 teeth) was then
separated into two subsets on the basis of the tooth wear
index for each tooth. The first subset, the normal wear
teeth (N = 1230 teeth), was comprised of all teeth that
were scored with a value of 2 or less on Hooper’s tooth
wear index since moderate tooth wear may be
considered normal [
]. The second subset, called the “severe
wear teeth” (N = 237 teeth), comprised of all teeth that
were scored with a value of 3 or greater on the tooth
wear index (Fig. 2).
The results of the independent t-tests for clinical
recession between the normal wear and severe wear
subsets revealed no significant differences for any tooth
class (Table 5).
For clinical crown height, significant differences were
found between the normal wear and the severe wear
teeth for all tooth classes except the maxillary first
molar. For all other tooth classes, the clinical crown
height measurements for teeth in the normal wear
subset were larger than the measurements for teeth in the
severe wear subset (Table 6). However, for gingival
margin-papillae, no significant differences were found
between the normal wear teeth and the severe wear
teeth (Table 7).
Table 8 lists the frequencies of teeth with and without
clinical recession and advanced tooth wear in the four
The means and standard deviations for the clinical
crown height and gingival margin-papillae
measurements (Tables 1 and 2) are reported to allow for
The focus of this study was to determine if either
clinical crown height or gingival margin-papillae could
serve as a quantitative indirect measure to detect
gingival recession. The clinical crown height
measurement detected differences in the position of the
gingival margins between the recession and
nonrecession teeth for all tooth classes, therefore giving a
true positive result where a difference was detected
and a difference did exist (Table 3). The gingival
margin-papillae measurement revealed similar results,
detecting a difference between the recession and
non-recession teeth, another true positive finding
comparison to other samples in the future. While
clinical crown height has been studied extensively in
children and adolescents [
], the gingival
margin-papillae measurement has never been
evaluated. With values for adults reported by race and by
gender, by individual tooth class from the central
incisor to the first molar, the effects of other variables
on the architecture of the gingiva can be studied. All
measurements were done by one investigator, 10 days
apart, and showed a significant correlation at the 0.01
level. However, multiple measures done by a series of
investigators would be necessary to determine the
reproducibility of the measures.
The ability of a measurement to detect a true positive
is useless unless the same measurement can provide a
true negative result, finding no difference where no
difference exists. To test this principle, the overall data set
was divided into two subsets—teeth with normal wear
and teeth with severe wear. There were no differences in
measures of clinical recession with respect to tooth wear
(Table 5). The clinical crown height measurement
(Table 6) found differences between the subsets with the
values for the normal wear teeth being larger than the
values for the severe wear teeth, which is a false positive
result since there was no difference in the gingival
architecture. However, in short-term studies, for example the
effect of orthodontic treatment, attrition is not likely to
The gingival margin-papillae measurement,
however, found no difference where no difference in the
position of the gingival margin existed, a true
negative finding (Table 7). The use of the adjacent
papillae as landmarks for the measurement of the
position of the gingival margin eliminates the
problems that result from tooth wear. It is important to
note that despite advanced recession, when the
periodontium is otherwise healthy, the interproximal
papillae maintain their position while the free
gingival margin recedes (Fig. 3a).
The gingival margin-papillae measurement may prove
most useful in diagnosing prodromal recession, when the
gingiva recedes but the root cementum has not been
exposed (Fig. 3b). Many clinicians intuitively visualize this
measure when they diagnose a tendency for gingival
When comparing the clinical crown height to the
gingival margin-papillae measurement, the latter not only
has the advantage of avoiding the problems attendant
with attrition but also sidesteps the variability of tooth
size in individuals due to race, sex, and genetic
p < .05, comparing the normal wear and severe wear subgroups; no significant
difference was found in the clinical recession due to tooth wear
Reprinted with permission from Eltink et al. [
Bruxism is the main cause of tooth wear and is
associated with excessive occlusal force that some clinicians
feel will cause abfraction and can lead to gingival
]. The data in this paper indicates that attrition
was not associated with an increase in both clinical
recession and the gingival margin-papillae measures
(Tables 5 and 7). Therefore, any association of
bruxism or abfraction to gingival recession was not
demonstrated in this study.
The Miller index, used by periodontists to classify
gingival recession, has four grades [
]. Grades 3 and
4 involve interproximal bone loss so that only grades
1 and 2 are appropriate measures in subjects
otherwise free of periodontal disease. Note that the Miller
index is not a quantitative measure of gingival
recession but it is useful in describing the severity of
recession into four clinical categories. The difference
between Miller grades 1 and 2 is the amount of
attached gingiva. In this paper, we did not attempt to
*p < .05, comparing the clinical crown between the normal wear and severe
wear subgroups and showing the significant differences for all tooth classes
due to a decrease in the clinical crown height in the severe wear group—a
false positive value
Reprinted with permission from Eltink et al. [
measure this level. Wennström has presented
evidence that the amount of attached gingiva is not
associated with the development of gingival recession
and that minimal attached gingiva is sufficient to
prevent recession .
Gingival recession is common in the adult
population with an otherwise healthy periodontium and was
observed in 20% of the teeth in the present study.
What is the cause of this variability of expression of
naturally occurring recession? Undoubtedly, one
factor is over-zealous tooth brushing [
genetically determined thickness of the alveolar bone and
soft tissue—the biotype—may be an important
variable of naturally occurring gingival recession [
especially if associated with bone dehiscences [
However, Cook et al. found that periodontal biotype
was unrelated to labial gingival recession [
] and plaque and calculus [
] are local
factors that can result in gingival recession. It would
appear that age-related gingival recession seen in
many adults is multifactorial and any of the above
factors may be contributory.
Reprinted with permission from Eltink et al. [
How useful will the measures of gingival recession and
tooth wear be in identifying differences in incidence
when the study group is divided by gender and race?
Table 8 lists the percentage of teeth with clinical
recession and severe tooth wear for the four demographic
groups. African-American females have less clinical
recession than African-American males (6 vs 19%) as well
as in Caucasian males and females (20%).
AfricanAmerican males and females have one half as much
tooth wear as their Caucasian counterparts. A detailed
statistical analysis confirming these differences appears
in previous publications [
Volchansky and Cleaton-Jones [
] studied clinical
crown height in 18-year-old Caucasians, and Bassey [
studied Nigerians aged 29.7 years. These authors,
however, were not focused on the problem of gingival
One of the limitations of this paper is the grouping of
all patients between the age of 20 and 59 years. A larger
sample would be required to demonstrate the level of
recession seen in each age group, which has been shown
to increase with age [
Applying the gingival margin-papillae measure intraorally
would be difficult, and therefore, study models are required.
However, the use of intraoral scans could make
accurate measurements possible without impressions and
study models, as the scans are easily converted into
digital models [
The three measures studied in this paper have strengths
and weaknesses. Gingival recession measured by a
periodontal probe to the nearest millimeter is clinically useful
but is semi-quantitative, cannot measure the earliest stages
of recession prior to cemental exposure, and is dependent
upon visualization of the cemento-enamel junction (CEJ)
which at times can be difficult to locate [
]. Crown length
is fine for short-term studies but, as shown in this paper,
will give false readings due to tooth wear with long-term
studies. The gingival margin-papillae measurement is more
time consuming to use and is not appropriate once
interproximal bone loss from periodontal disease is present, but
it is not dependent upon visualizing the CEJ and not
affected by attrition. When orthodontic study models, or
virtual models are available, both crown length and the
gingival margin-papillae can be quantified to at least a
tenth of a millimeter. Gingival hyperplasia is often seen at
the time of debonding but usually recedes by the time
records are taken. This hyperplasia will affect all three
measures, but papillary hyperplasia will be more of a
problem for the gingival papilla measure.
The quantitative measures presented in this paper will
be valuable in the study of gingival recession that may be
associated with orthodontic tooth movement that
challenges the limits of the alveolus, for example lower incisor
] and buccal expansion [
gingival margin-papillae measure would be useful in
following surgical procedures to correct gingival recession
] especially followed over time.
Recent interest in expansion of the anterior and
posterior dental alveolus has been stimulated by the Damon
self-ligating bracket system [
] and the use of
Invisalign for expansion . The standards presented in
this paper would be useful in evaluating recession in the
above treatments, especially long-term results.
Accelerated osteogenic orthodontic techniques involve
flapping of the gingiva, corticotomy, and usually bone
grafting in an effort to increase the width of the alveolus
for expansion [
]. We need more data, both short- and
long-term, to evaluate the potential impact on gingival
The power of measures of gingival recession and
tooth attrition is demonstrated in the differences seen
in the four demographic groups studied (Table 8).
This will be very useful in epidemiological studies, for
example comparison of subjects with abrasive versus
Clinical recession, clinical crown height, and gingival
margin-papillae measurements all have advantages and
disadvantages and, therefore, could be considered
together to provide an accurate and precise assessment
of the architecture of the gingival tissue.
1. Two quantitative measures that indirectly measure
gingival recession—clinical crown height and the
gingival margin-papillae measure—are presented for
four demographic groups (Caucasian and
AfricanAmerican males and females) for all teeth from the
central incisors to and including the first molars.
2. Segregating the total group by teeth with recession
and without recession demonstrates that both
measures report an increased value associated with
recession, a positive finding.
3. Segregating the total group by teeth with severe
wear and normal wear demonstrates a decrease in
the clinical crown height measure due to the shorter
tooth which could mask gingival recession. The
gingival margin-papillae measure, however, was not
altered by tooth wear.
4. Tooth wear usually caused by bruxism was not
associated with an increase in gingival recession.
5. Measures for gingival recession and tooth wear were
different for the four demographic groups studied,
indicating the power of these measures in future
6. The clinical crown height and gingival
marginpapillae measures can be used to precisely quantify
gingival recession following orthodontic and/or
The authors wish to thank Dr. Charles Greene of the Department of Orthodontics
and Dr. Michael Schmerman and Salvador Nares of the Department of
Periodontics, all at the College of Dentistry at the University of Illinois at Chicago,
for their suggestions for improving the manuscript.
All authors contributed equally. All authors read and approved the final
Ethics approval and consent to participate
IRB approval has been obtained for this project and is listed in the
The authors declare that they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in
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