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THE ASSESSMENT OF GINGIVAL MARGINS OF MAXILLARY CANINES IN
UNTREATED ADOLESCENT PATIENTS WITH CONGENITALLY MISSING
PERMANENT MAXILLARY LATERAL INCISORS
Gregory W. Carr, D.M.D.
An Abstract Presented to the Graduate Faculty of
Saint Louis University in Partial Fulfillment
of the Requirements for the Degree of
Master of Science in Dentistry
2013
Abstract
Introduction:
A significant number of people in the
population are congenitally missing permanent maxillary
lateral incisors.
In these patients, the adjacent
permanent maxillary canine frequently erupts in a more
mesial position within the dental arch closer to the
maxillary central incisor.
No study to date has looked at
the natural gingival margin relationship between permanent
maxillary central incisors and mesial erupted permanent
maxillary canines.
Purpose:
The purpose of this study is
to determine, in patients who are congenitally missing
permanent maxillary lateral incisors, if the natural
gingival margin relationship between the maxillary central
incisor and the more mesial erupted maxillary canine is
similar to the natural gingival margin relationship between
the maxillary central incisor and maxillary lateral
incisor.
Materials and Methods:
The sample consisted of
60 patients (29 male, 31 female) between 10 and 18 years of
age who were congenitally missing at least one permanent
maxillary lateral incisor.
A total of 81 maxillary
quadrants qualified to be used in the sample.
Plaster
casts were obtained from the initial records of each
patient in the sample and then scanned using a 3D scanner.
1
The distance from the gingival margin of the maxillary
central incisor and maxillary canine to a horizontal plane
was measured in order to show their gingival margin
relationship. Descriptive statistics for these parameters
were calculated and non-parametric tests were run to
evaluate left vs. right quadrants and male vs. female
quadrants.
Results:
Of 81 maxillary canines, compared to
the maxillary central incisor, the gingival margin for 33
of them was apical to the gingival margin of the central
incisor, 12 were 0.0 - 0.5 mm incisal, 17 were 0.5 – 1.0 mm
incisal, and 19 were greater than 1.0 mm incisal to the
gingival margin of the central incisor.
Conclusions:
Mesial erupted permanent maxillary canines in adolescents
who are congenitally missing permanent maxillary lateral
incisors have a gingival margin that is apical to the
gingival margin of the permanent maxillary central incisor
40.30% of the time, and incisal to the gingival margin of
the permanent maxillary central incisor 59.30% of the time.
2
THE ASSESSMENT OF GINGIVAL MARGINS OF MAXILLARY CANINES IN
UNTREATED ADOLESCENT PATIENTS WITH CONGENITALLY MISSING
PERMANENT MAXILLARY LATERAL INCISORS
Gregory W. Carr, D.M.D.
A Thesis Presented to the Graduate Faculty of Saint
Louis University in Partial Fulfillment
of the Requirements for the Degree of
Master of Science in Dentistry
2013
COMMITTEE IN CHARGE OF CANDIDACY:
Professor Eustaquio A. Araujo,
Chairperson and Advisor
Associate Professor Ki Beom Kim
Associate Clinical Professor Donald R. Oliver
i
DEDICATION
I dedicate this thesis to my supportive and wonderful
family.
To my wife and best friend, Jenna, who has supported
me and been my rock through this whole journey:
Thank you
for always being there for me and lifting me up during the
tough times of school.
Thank you for all of the sacrifices
that you have made during the past 8 years.
I could not
have made it this far without you by my side.
Thank you
for taking a chance and marrying me.
To my three amazing children: Brinley, Julianne, and
McKay.
life.
Thank you for bringing so much joy and love into my
I am grateful to be your daddy.
To my parents, Michael and Carole Carr:
Thank you for
teaching me the value of hard work and perseverance.
Thank
you for always encouraging me to reach for my dreams and
for the great example that you have been to me in life.
And lastly, to the faculty of Saint Louis University:
I am honored to have been trained under your guidance.
Thank you for caring so much about my education and my
future success.
This has been an amazing 2½ years.
ii
ACKNOWLEDGEMENTS
This project could not have been completed without the
help and support of the following individuals:
Dr. Eustaquio Araujo, Dr. Ki Boem Kim, and Dr. Donald
Oliver.
Thank you for all the time, effort, and guidance
that each of you gave to me in planning and completing this
project.
Dr. Heidi Israel.
Thank you for your assistance with
the statistical analysis for this thesis.
iii
TABLE OF CONTENTS
List of Tables.............................................v
List of Figures...........................................vi
CHAPTER 1: INTRODUCTION....................................1
CHAPTER 2: REVIEW OF THE LITERATURE
Tooth Agenesis ..................................5
Tooth Agenesis Theories .........................7
Management of a Missing Maxillary
Lateral Incisor ................................10
Canine Substitution ............................12
Single-Tooth Implants..........................14
Tooth-Supported Restorations...................16
Eruption of Permanent Maxillary Canines........17
Lateral Incisor Gingival Margin Level..........19
Statement of thesis ............................21
Literature Cited ...............................23
CHAPTER 3: JOURNAL ARTICLE
Abstract .......................................30
Introduction ...................................32
Materials and methods ..........................36
Sample.....................................36
Statistical Analysis.......................41
Reliability................................41
Results ........................................42
Discussion .....................................47
Conclusion .....................................53
Literature Cited ...............................54
Vita Auctoris............................................. 57
iv
LIST OF TABLES
Table 3.1
Descriptive statistics for U1-P,
U3-P, and U1-U3............................42
Table 3.2
Descriptive statistics for U1-P, U3-P,
and U1-U3 of the right quadrants...........43
Table 3.3
Descriptive statistics for U1-P, U3-P,
and U1-U3 of the left quadrants............43
Table 3.4
Descriptive statistics for U1-P, U3-P,
and U1-U3 of the male quadrants............45
Table 3.5
Descriptive statistics for U1-P, U3-P,
and U1-U3 of the female quadrants..........46
v
LIST OF FIGURES
Figure 3.1
Construction of horizontal reference
plane......................................38
Figure 3.2
Measurements from the highest point of
contour on the buccal gingival margin of
maxillary central incisor and maxillary
canine to the horizontal reference plane...39
Figure 3.3
Maxillary canine gingival margin
relationship to the maxillary central
incisor gingival margin....................44
Figure 3.4
Maxillary canine gingival margin
relationship to the maxillary central
incisor gingival margin: Left vs. Right
quadrants..................................45
Figure 3.5
Maxillary canine gingival margin
relationship to the maxillary central
incisor gingival margin: Male vs. Female
quadrants..................................46
vi
CHAPTER 1: INTRODUCTION
To close or not to close; which is better?
This is
the age old question that orthodontists have been trying to
answer for years when treatment planning patients who are
missing maxillary lateral incisors.
A significant number of people in the population are
congenitally missing permanent maxillary lateral
incisors.1-5
The demand for orthodontic treatment by these
people is high because of the obvious impact that this
condition has on both dental and facial esthetics.6
This is
a challenging situation that every orthodontist will
encounter on a regular basis.
There are multiple options when treatment planning
these patients.6
One option is to close the lateral incisor
space by moving the canine until it is adjacent to the
central incisor and then reshaping it to look like the
lateral incisor through a process called canine
substitution.
The other option is to place the canine at
its natural position within the dental arch, filling the
void left by the missing lateral incisor with either a
single-tooth implant or a tooth-supported restoration.7-11
A thorough diagnostic protocol should be used in
determining which option is best for each patient.6
1
Many
articles have been written suggesting that there are
certain dental and facial criteria that should be analyzed
before deciding which option to choose.
They include
malocclusion, amount of crowding, profile, canine shape and
color, and level of the lip.6,
11-14
Another criteria to
consider, that isn’t mentioned often in the literature is
the position in the dental arch where the canine erupts.
A recent study by Rendon found that when the permanent
maxillary lateral incisor was missing, the canine erupted
in a more mesial position within the dental arch closer to
the midalveolar plane.15
Araujo also suggests that in
patients with congenitally missing maxillary lateral
incisors, canines frequently show a mesial pattern of
eruption, with a final position in the dental arch that is
adjacent and parallel to the central incisors, and that
such a condition favors canine substitution.6
In patients that are congenitally missing maxillary
lateral incisors, one more criteria to consider that isn’t
mentioned in the literature is the gingival margin of the
maxillary canine that erupts into the space normally
occupied by the maxillary lateral incisor, and its
relationship to the gingival margin of the maxillary
central incisor.
Is the relationship between the gingival
margins like a normal maxillary central incisor/maxillary
2
canine relationship, where the gingival margins are at the
same level?
Or, is the relationship between the gingival
margins of the maxillary central incisor and canine more
like a maxillary central incisor/maxillary lateral incisor
relationship, where the lateral incisor gingival margin in
more incisal than the gingival margin of the maxillary
central incisor?
Multiple studies have tried to determine what the most
esthetic gingival margin relationship is between a
maxillary central incisor and a maxillary lateral incisor.
This was accomplished by using smiling photographs of the
same smile in which only the gingival margin relationship
between the maxillary central and lateral incisors had been
altered in certain increments.
Lay people, dentists, and
dental specialists were then asked which photographs they
thought were the most esthetic.16-19
Other studies tried to determine what the most common
relationship was between maxillary central incisors and
maxillary lateral incisors in the dental arch.
This was
accomplished by obtaining measurements directly from
plaster model casts using digital calipers and from digital
photographs of model casts using computer software.20,
21
One study looked at smiling photographs of a patient
who was congenitally missing a maxillary lateral incisor
3
and had the space closed by canine substitution.
Each
photograph was different only in the gingival margin
relationship between the maxillary central incisor and the
maxillary canine that had been moved into the lateral
incisor position adjacent to the canine. Lay people,
dentists, and orthodontists were then asked to rank the
pictures according to attractiveness to determine which
gingival margin relationship between the maxillary central
incisor and a substituted maxillary canine was the most
esthetic.22
To my knowledge, no study to date has looked at the
natural gingival margin relationship between maxillary
central incisors and maxillary canines that have erupted
into the maxillary lateral incisor position, before being
treated with orthodontics.
The purpose of this study is to determine, in patients
who are congenitally missing permanent maxillary lateral
incisors, if the natural gingival margin relationship
between the maxillary central incisor and the more mesial
erupted maxillary canine is similar to the natural gingival
margin relationship between the maxillary central incisor
and maxillary lateral incisor.
4
CHAPTER 2: REVIEW OF THE LITERATURE
Tooth Agenesis
Agenesis of one or more teeth, also known as
hypodontia, is the most common developmental dental anomaly
in man.23,
24
Several terms are used in the literature to
describe missing teeth; Anodontia is the complete absence
of teeth; Oligodontia is referred to as partial anodontia,
characterized by having six or more teeth absent, not
including the third molars; Hypodontia is a term used to
denote that teeth are missing, but usually less than six.25
Hypodontia not only describes missing teeth, but it also
may denote that the size or shape of teeth are reduced as
well.26
Tooth agenesis affects the permanent dentition more
frequently than the primary dentition. The incidence for
permanent tooth agenesis ranges from 2.30% - 6.01%,
excluding third molars.1-3,
27, 28
In the primary dentition,
tooth agenesis ranges from 0.20% - 0.90%.29,
30
The most common missing tooth is the third molar, with
an incidence of about 20%.27
As for which tooth is the
second and third most common, the literature varies.
studies show that the maxillary lateral incisor is the
5
Some
second most commonly missing tooth.1,
28
Others show that
the absence of the mandibular second premolar is more
frequent than the maxillary lateral incisor.2-5
According to the literature, there are a number of
correlations that exist with respect to agenesis and the
permanent dentition.
Females have a higher frequency of
tooth agenesis than males.1,
31, 32
Silverman and Bailit
found in their respective studies that agenesis more
commonly occurs bilaterally than unilaterally and is
symmetric, except in cases involving the maxillary lateral
incisor.3,
33
On the other hand, Polder and colleagues found
tooth agenesis to be more common unilaterally, except in
cases involving the maxillary lateral incisor, which they
found to occur more often bilaterally.4
A study by Muller et al found an interesting
correlation between the number and type of missing teeth.
The study examined 14,940 adolescents and noticed in those
who were congenitally missing only one or two teeth, the
greatest frequency was related to the maxillary lateral
incisor.
However, in those adolescents who were missing
more than two teeth, the mandibular second premolar was
missing more often.1
Alvesalo and Portin found a
relationship between missing teeth and abnormalities in the
shape of the remaining teeth.
The authors noticed that
6
when one maxillary lateral incisor was missing, the
contralateral maxillary lateral incisor could be smaller
than normal.34
Tooth agenesis theories
The etiology of tooth agenesis is not very clear. Is
it genetic, environmental, or evolutionary? Or, could it be
multifactorial and may be due to a combination of these?
Many attempts have been made, and many theories have been
hypothesized, to explain why tooth agenesis occurs.
It has been shown that genetic factors with a marked
degree of penetrance play a major role in dental agenesis.
Grahnen suggested that tooth agenesis is usually
transmitted as an autosomal dominant trait with incomplete
penetrance and variable expressivity.35
In Woolf’s study,
it was found that the frequency of individuals with a
missing maxillary lateral incisor was significantly
increased in the parents and siblings of the examined
subject as compared with the frequency of the parents and
siblings of the control subjects.
The study concludes that
agenesis of maxillary lateral incisors consists of a
7
dominant autosomal gene showing reduced penetrance and
variable expressivity.36
Sofaer et al postulated that for teeth developing in a
confined space, there is a compensatory interaction between
tooth germs during development.
In their study, they
examined Hawaiian children and noticed that if the central
incisor is large, then the adjacent lateral incisor tends
to be absent. If the lateral incisor is peg-shaped, then
the central incisor is present, but tends to be smaller
than normal.
They propose that agenesis occurs when there
is insufficient primordium for tooth germ initiation, and
peg-shaped laterals occur when there is sufficient
primordium but a poor environment.37
Since the maxillary
lateral incisor develops after the maxillary central
incisor, their initiation depends on the availability of
the necessary local requirements.33,
37
In 1939, Butler proposed a theory as to why some teeth
fail to form more than others.
According to his theory,
the mammalian dentition can be divided into three
developmental fields consisting of incisors, canines, and
premolars/molars.
Within each field, one tooth is
designated at the “key” tooth, meaning that it is more
stable developmentally.
On either side of this key tooth,
8
the remaining teeth within the developmental field become
more and more unstable.
Considering each quadrant
separately, the key tooth in the premolar/molar field would
consist of the first molar with the second and third molars
on the distal end of the field and the first and second
premolars on the mesial end of the field.
According to
Butler’s theory, the third molar and first premolar would
be the most variable in size and shape.
Many clinicians
would agree with this theory in respect with the third
molar, but not so with the first premolar.
It is important
to observe that the earliest mammals had four premolars and
some of the higher primates, including humans, have lost
the first two.
The remaining premolars in reality should
be called the third and fourth premolars.
Therefore, as
Butler’s theory predicted, the two lost premolars would
have been farthest from the first molar, and in an
evolutionary sense considered unstable.33
Clayton noticed in a study with 3,557 human subjects
that the terminal or most posterior tooth of a tooth series
(incisors, premolars, molars) was most frequently missing,
and hypothesized that those teeth most often missing were
“vestigial organs” that had little practical value for
modern man.27
Hence, in the evolutionary process, these
9
teeth provide no selective advantage and therefore have
been lost.38
Management of a missing maxillary lateral incisor
The demand for orthodontic treatment by patients with
missing maxillary lateral incisors is high because of the
obvious impact that this condition has on facial esthetics.
Not only can this condition adversely affect someone’s
self-esteem, but it may also adversely affect the way other
people view them in society.39,
40
Treatment planning for these patients can be
challenging.
There are many concerns one needs to be aware
of when planning these cases because the congenital absence
of one or both of these teeth introduces an imbalance in
maxillary and mandibular dental arch lengths in the
permanent dentition.
The most predictable way to achieve
the optimal esthetic and functional result is to use an
interdisciplinary team consisting of a general dentist,
orthodontist, periodontist, oral surgeon, and
prosthodontist.7,
12, 14, 41, 42
Together, they should elaborate
and create the patient’s treatment plan and communicate
throughout the course of treatment to make sure that all
10
aspects of treatment are considered and the overall
treatment objectives are achieved.12
There are multiple options that exist for treating
these patients.
The space sometimes closes spontaneously.
If not, the space can be closed orthodontically through a
process called canine substitution.
This is done by moving
the maxillary canine into the position normally occupied by
the maxillary lateral incisor and then reshaping it to look
more like the lateral incisor.
The other option is to
place the canine at its normal position within the arch,
creating space for either a single-tooth implant or a
tooth-supported restoration.7-11
When deciding which treatment option to use, primary
consideration should be given to the least invasive option
that conserves tooth structure and satisfies the expected
esthetic and functional objectives.
Whichever option is
chosen, it is important to complete a diagnostic wax-up.
This helps the interdisciplinary team evaluate the final
occlusion and determine if an esthetic final result is
obtainable.8,
10, 43
11
Canine substitution
There are certain facial and dental criteria that need
to be evaluated before deciding upon canine substitution as
the treatment of choice for patients that are missing
maxillary lateral incisors.
They include malocclusion,
amount of crowding, profile, canine shape and color, and
level of the lip.12,
13
There are two principal types of malocclusion that
allow for canine substitution to occur.
The first one is
an Angle Class II malocclusion with no crowding in the
mandibular arch indicating that no extractions are
necessary.
II.
This scenario would leave the molars in Class
The second one is an Angle Class I malocclusion with
enough crowding in the mandibular arch indicating that
extractions are necessary.
In these cases, the molar
relationship would be Class I.7,
11, 44
Generally, a convex to straight profile would respond
well to canine substitution.7
The shape and color of the canines are also important
factors to look at before deciding upon canine
substitution.
The canine is a significantly larger tooth
than the lateral incisor, and its buccal surface is more
convex.
Because of this size discrepancy, an anterior
12
tooth size excess in the maxillary arch would be created
and anatomical adjustment must be performed to reduce the
discrepancy and to establish an anterior occlusion with a
normal overbite and overjet relationship.12
As the canines
are recontoured for esthetic and functional purposes, one
must take into account the darker color and less
translucent that the canine will display compared to the
adjacent teeth.11
This can be corrected by either bleaching
the canine or placing a veneer on it.7,
10
If the patient’s lip level when smiling is in a
position that allows the gingival margins to be visible,
the gingival margin of the canine should be placed 0.5 1.0 mm incisal to the gingival margin of the central
incisor.7
Also, according to Senty, if the patient has a
high smile line, a prominent canine root eminence could
generate an esthetic concern.43
An advantage of closing space by canine substitution
is the permanence of the final result, eliminating the need
for long-term temporary restorations that are often needed
until the patient is old enough for a permanent prosthesis,
and avoiding the long-term maintenance required for the
prosthesis over the patient’s lifetime which can be
costly.8-10,
22
Multiple clinicians have found that patients
who had canine substitution were also healthier
13
periodontally than those who had a prosthesis placed.5,
11, 45
And some studies have shown that patients who had canine
substitution were more satisfied with the appearance of
their teeth than those who had a prosthesis placed.5,
11
The disadvantages of canine substitution include the
need to remove tooth structure on the canine and first
premolar, and potential additional expenses if the canines
need cosmetic bonding to improve the esthetic result.8-10
Robertsson and Mohlin found in their study that patients
who had canine substitution were dissatisfied with the lack
of color balance of the maxillary canine and the adjacent
teeth.5
Single-tooth implants
Many patients do not meet the ideal facial and dental
criteria for canine substitution.
For these patients, some
form of restoration must be considered.14
Today, one of the most common treatment alternatives
for replacing missing teeth is the single-tooth implant.46-48
Advantages of opening up space for implants include
maintaining the canine in its natural position within the
dental arch and preserving tooth structure of the canine
and the adjacent teeth, making this the most conservative
14
of the prosthodontic options for replacing missing lateral
incisors.8,
10, 49
Various studies have shown high success
rates of implants and long-term function of the
restorations supported by single-tooth implants.50
With the
hard and soft tissue grafting procedures that are available
today, a more esthetic outcome has become increasingly
predictable.51,
52
One of the disadvantages of opening up space to place
an implant is that implants cannot be placed until facial
growth is complete.
If an implant is placed before facial
growth is complete, significant periodontal, occlusal, and
esthetic problems can occur.53
As the face grows and the
mandibular rami lengthen, the natural teeth erupt to stay
in occlusion.
Once implants are osseointegrated in the
bone they become static and cannot erupt.
The timing for
implant placement after the end of facial growth is usually
about 16 - 17 years of age for girls and 20 - 21 years of
age for boys.41
Other disadvantages include the additional expense of
a dental prosthesis and the potential recurrence of these
expenses throughout the patient’s life, and the need for
long-term maintenance of the space with a temporary
retainer until the patient’s facial growth has ceased.8-10
15
Tooth-supported restorations
In situations when the patient does not meet the
criteria for canine substitution and does not want an
implant, some form of tooth-supported prosthesis can be
used.
The three most common tooth-supported restorations
used today are resin-bonded fixed partial dentures (FPD),
cantilevered FPD, and conventional full-coverage FPD.
The
ideal treatment should be the least invasive and should
satisfy the expected esthetic and functional objectives.14
The most conservative tooth-supported restoration is
the resin-bonded FPD because it requires only a minimal
amount of tooth structure be removed from the adjacent
teeth. These restorations can be used successfully, but
certain criteria must be met to ensure optimal esthetics
and long-term success.14
54, 55
A classic resin-bonded FPD
relies solely on adhesion as it is bonded to the lingual
surfaces of adjacent teeth without any grooves or pins.
The success rate for these restorations varies widely from
a 54% failure rate over 11 years to a 10% failure rate over
11 years, with debond as the primary cause of failure.54-57
The second most conservative tooth-supported
restoration is the cantilevered FPD.
16
It can be designed as
either a partial coverage or full coverage retainer using
the canine as the abutment.
If the facial esthetics of the
canine abutment is acceptable, a partial coverage retainer
is best.
A full coverage retainer is a better choice if
the facial contour of the canine needs to be changed to
improve the esthetics.14
Decock et al found in their study
of 137 cantilever FPDs a success rate of 70% over an 18
year period, with secondary caries as the main cause of
failure.58
The least conservative tooth-supported restoration is
the conventional full-coverage FPD.
This restoration is
the best choice if an existing FPD needs to be replaced or
if the adjacent teeth require restorations for either
structural reasons or alteration of the facial esthetics.
Due to the significant amount of tooth structure that is
removed to make these restorations, it is not the ideal
treatment for young patients missing maxillary lateral
incisors.14
Eruption of permanent maxillary canines
Before the maxillary canine begins eruption, it’s
dental follicle is located above the follicle of the
maxillary first premolar.59
Once eruption begins, it moves
17
in a mesial, occlusal direction to reach its proper
position within the arch.
As it erupts, it also increases
its crown inclination mesially until a maximum inclination
is reached at about 9 years of age.
At this time, the tip
of the maxillary canine contacts the distal aspect of the
root of the lateral incisor, causing the canine to
gradually upright itself in a more vertical position and
complete its
eruption in a buccal, occlusal direction.60
The final position of the permanent maxillary canine
is influenced by the permanent maxillary lateral incisor.
The intimate relationship between the maxillary canine and
the distal aspect of the root of the maxillary lateral
incisor appears to be an important factor in guiding the
normal eruption pathway of the maxillary canine.61
If the
lateral incisor is absent, peg, or smaller than normal, the
canine may lose its guidance and move toward a different
pathway that might involve the distal aspect of the root of
the maxillary central incisor, or it could move in a
palatal direction and become impacted.61-63
Rendon looked at the effect of congenitally missing
lateral incisors on the eruption of the maxillary canine.15
He found that when the maxillary lateral incisor was
missing, the canine initially has a similar position to the
canine in a normal dentition, but during its eruption the
18
maxillary canine moves more toward the mesial so that it
has a final position in the arch with the crown more
inclined mesially and located closer to the midalveolar
plane.15
Lateral incisor gingival margin level
One of the main reasons why patients seek orthodontic
care is to improve the esthetics of their smile.
The
relationship between the gingival margins of the maxillary
central, lateral, and canine teeth is one of the aspects
12, 64 65
that create an esthetic smile.
Many clinicians believe that the gingival margins of
the maxillary central incisor and the maxillary canine
should be at the same level, with the gingival margin of
the maxillary lateral incisor slightly more coronal.20-22,
66
However, opinions vary as to how coronal the gingival
margin of the lateral incisor should be when compared to
the maxillary central and canine.
Chu et al looked at a sample of 20 patients between 20
- 47 years of age and found the maxillary lateral incisor
on average 1.0 mm coronal to the maxillary central incisor
and canine teeth.21
Charruel and co-authors investigated
103 young adults and found that 81% of the lateral incisors
19
were coronal to the central incisor and canine, with 54%
being between 0.0 - 1.0 mm, and 27% being greater than 1.0
mm.20
Kokich and Spear, however, suggests that ideally the
maxillary lateral incisor should be 0.5 mm coronal to the
maxillary central incisor and canine teeth.12
When lay people were surveyed using photographs to
determine what they thought was the most esthetic gingival
margin relationship, Springer and others found the ideal
discrepancy between maxillary central and lateral incisors
to be 0.4 mm.17
In Kokich’s study, lay people found the
maxillary lateral incisor to be most esthetic when its
gingival margin was 1.0 mm coronal to the gingival margin
of the maxillary central incisor.16
What about the gingival margins of canines that have
been moved into the lateral incisor position by canine
substitution?
An investigation by Brough, Donaldson, and
Naini studied 120 people, equally divided between lay
people, orthodontists, and dentists, and ranked a series of
images of a smiling mouth from a patient treated with
canine substitution.22
The image ranked most attractive had
the gingival margin of the canine in the lateral incisor
position as 0.5 mm coronal to the level of the adjacent
central incisor.
20
Statement of Thesis
The literature shows a significant number of missing
teeth in the population, specifically the permanent
maxillary lateral incisor.1-5
In these cases, there are
multiple options for treatment.6-11
Multiple studies have
shown how the presence or absence of the permanent
maxillary lateral incisor can affect the eruption pathway
and final position of the permanent maxillary canine.15,
61-63
Some studies have shown what the most esthetic and most
common relationship is between the gingival margins of the
maxillary central incisor and the adjacent lateral
incisor.16-21
One study even showed what the most esthetic
relationship is between a maxillary central incisor and a
maxillary canine that has been substituted for a maxillary
lateral incisor.22
No study to date has looked at the gingival margins of
permanent maxillary canines that have erupted into the
position within the dental arch where the permanent
maxillary lateral incisors normally are, and the
relationship between its gingival margin and the gingival
margin of the maxillary central incisor, in untreated
21
adolescents who are congenitally missing permanent
maxillary lateral incisors.
The hypothesis of this study is that the permanent
maxillary canine that erupts into the lateral incisor
position will have a similar gingival relationship to the
maxillary central incisor as a natural lateral incisor
would have if present.
22
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27
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28
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2003;124:116-27.
29
CHAPTER 3: JOURNAL ARTICLE
Abstract
Introduction:
A significant number of people in the
population are congenitally missing permanent maxillary
lateral incisors.
In these patients, the adjacent
permanent maxillary canine frequently erupts in a more
mesial position within the dental arch closer to the
maxillary central incisor.
No study to date has looked at
the natural gingival margin relationship between permanent
maxillary central incisors and mesial erupted permanent
maxillary canines.
Purpose:
The purpose of this study is
to determine, in patients who are congenitally missing
permanent maxillary lateral incisors, if the natural
gingival margin relationship between the maxillary central
incisor and the more mesial erupted maxillary canine is
similar to the natural gingival margin relationship between
the maxillary central incisor and maxillary lateral
incisor.
Materials and Methods:
The sample consisted of
60 patients (29 male, 31 female) between 10 and 18 years of
age who were congenitally missing at least one permanent
maxillary lateral incisor.
A total of 81 maxillary
quadrants qualified to be used in the sample.
30
Plaster
casts were obtained from the initial records of each
patient in the sample and then scanned using a 3D scanner.
The distance from the gingival margin of the maxillary
central incisor and maxillary canine to a horizontal plane
was measured in order to show their gingival margin
relationship. Descriptive statistics for these parameters
were calculated and non-parametric tests were run to
evaluate left vs. right quadrants and male vs. female
quadrants.
Results:
Of 81 maxillary canines, compared to
the maxillary central incisor, the gingival margin for 33
of them was apical to the gingival margin of the central
incisor, 12 were 0.0 - 0.5 mm incisal, 17 were 0.5 – 1.0 mm
incisal, and 19 were greater than 1.0 mm incisal to the
gingival margin of the central incisor.
Conclusions:
Mesial erupted permanent maxillary canines in adolescents
who are congenitally missing permanent maxillary lateral
incisors have a gingival margin that is apical to the
gingival margin of the permanent maxillary central incisor
40.30% of the time, and incisal to the gingival margin of
the permanent maxillary central incisor 59.30% of the time.
31
Introduction
To close or not to close; which is better?
This is
the age old question that orthodontists have been trying to
answer for years when treatment planning patients who are
congenitally missing maxillary lateral incisors.
A significant number of people in the population are
congenitally missing permanent maxillary lateral incisors.15
The demand for orthodontic treatment by these people is
high because of the obvious impact that this condition has
on both dental and facial esthetics.6
This is a challenging
situation that every orthodontist will encounter on a
regular basis.
There are multiple options when treatment planning
these patients.6
One option is to close the lateral incisor
space by moving the canine until it is adjacent to the
central incisor and then reshaping it to look like the
lateral incisor through a process called canine
substitution.
The other option is to place the canine at
its natural position within the dental arch, filling the
void left by the missing lateral incisor with either a
single-tooth implant or a tooth-supported restoration.7-11
A thorough diagnostic protocol should be used in
determining which option is best for each patient.6
32
Many
articles have been written suggesting that there are
certain dental and facial criteria that should be analyzed
before deciding which option to choose.
They include
malocclusion, amount of crowding, profile, canine shape and
color, and level of the lip.6,
11-14
Another criterion to consider that isn’t mentioned
often in the literature is the position in the dental arch
where the canine erupts.
A recent study by Rendon found
that when the permanent maxillary lateral incisor was
missing, the permanent maxillary canine erupted in a more
mesial position within the dental arch closer to the
midalveolar plane.15
Araujo also suggests that in patients
with congenitally missing maxillary lateral incisors,
maxillary canines frequently show a mesial pattern of
eruption, with a final position in the dental arch that is
adjacent and parallel to the central incisors, and that
such a condition favors canine substitution.6
In patients that are congenitally missing maxillary
lateral incisors, one more criteria to consider that isn’t
mentioned in the literature is the gingival margin of the
maxillary canine that erupts into the space normally
occupied by the maxillary lateral incisor, and its
relationship to the gingival margin of the maxillary
central incisor.
Is the relationship between these
33
gingival margins like a normal maxillary central
incisor/maxillary canine relationship, where the gingival
margins are at the same level?
Or, is the relationship
between the gingival margins of the maxillary central
incisor and canine more like a maxillary central
incisor/maxillary lateral incisor relationship, where the
lateral incisor gingival margin in more incisal than the
gingival margin of the maxillary central incisor?
Multiple studies have tried to determine what the most
esthetic gingival margin relationship is between a
maxillary central incisor and a maxillary lateral incisor.
This was accomplished by using smiling photographs of the
same smile in which only the gingival margin relationship
between the maxillary central and lateral incisors had been
altered in certain increments.
Lay people, dentists, and
dental specialists were then asked which photographs they
thought were the most esthetic.16-19
Other studies tried to determine what the most common
relationship was between maxillary central incisors and
maxillary lateral incisors in the dental arch.
This was
accomplished by obtaining measurements directly from
plaster model casts using digital calipers and from digital
photographs of model casts using computer software.20,
34
21
One study looked at smiling photographs of a patient
who was congenitally missing a maxillary lateral incisor
and had the space closed by canine substitution.
Each
photograph was different only in the gingival margin
relationship between the maxillary central incisor and the
maxillary canine that had been moved into the lateral
incisor position adjacent to the canine. Lay people,
dentists, and orthodontists were then asked to rank the
pictures according to attractiveness to determine which
gingival margin relationship between the maxillary central
incisor and a substituted maxillary canine was the most
esthetic.22
To my knowledge, no study to date has looked directly
at the natural gingival margin relationship between
maxillary central incisors and maxillary canines that have
erupted into the maxillary lateral incisor position, before
being treated with orthodontics.
This knowledge would be
useful to orthodontists in treatment planning patients who
are congenitally missing permanent maxillary lateral
incisors by adding another criterion to look at when
deciding which treatment option to choose.
The purpose of this study is to determine, in patients
who are congenitally missing permanent maxillary lateral
incisors, if the natural gingival margin relationship
35
between the maxillary central incisor and the more mesial
erupted maxillary canine is similar to the natural gingival
margin relationship between the maxillary central incisor
and maxillary lateral incisor.
A secondary purpose of this
study is to determine if the gingival margin relationship
between the permanent maxillary central incisor and the
more mesial erupted permanent maxillary canine is similar
in relation to male vs. female and left vs. right side of
the dentition.
Materials and Methods
Sample
This is a retrospective study approved by the
Institutional Review Board at Saint Louis University.
The
sample consisted of 60 patients (29 male, 31 female) who
had either finished orthodontic treatment or had already
started orthodontic treatment at the Center for Advanced
Dental Education at Saint Louis University. The mean age of
the sample was 13 years and 4 months, with a range from 10
to 18 years of age.
Of the 60 patients in the sample, 21 were bilaterally
missing the maxillary lateral incisor and 39 were
unilaterally missing the maxillary lateral incisor.
36
A
total of 81 maxillary quadrants with a missing lateral
incisor were used in the sample.
Forty-one quadrants were
on the right side and 40 quadrants were on the left side.
The subjects were selected based on the following
criteria: (1) Caucasian, (2) must have had at least one
congenitally missing permanent maxillary lateral incisor,
(3) the permanent maxillary canine on the same side as the
missing permanent maxillary lateral incisor must have
already completely erupted into the dental arch, (4) the
permanent maxillary canine must have erupted into a
position that is more mesial than the normal canine
position, (5) the patient could not have been treated
previously with orthodontics.
No control group was used.
Instead, a review of the
literature was performed to determine that the most common
gingival margin relationship between the permanent
maxillary central incisor and the permanent maxillary
lateral incisor is between 0.5 – 1.0 mm.19-21
Maxillary and mandibular dental casts were obtained
from the initial records of each patient in the sample.
The casts were scanned using a 3D scanner (R700, 3Shape
A/S, Copenhagen, Denmark), and measurements were obtained
using the OrthoAnalyser software (3Shape A/S).
37
Reference points were marked on the digital images in
order to obtain the needed measurements.
A horizontal
reference plane was first created by making and connecting
three marks on each scanned model (Figure 3.1).
The first
mark was placed at the highest point of contour on the
palatal gingival margin of the maxillary right central
incisor.
The second mark was placed on the palatal
gingival margin directly vertical from the distolingual
groove of the maxillary right first molar.
The third mark
was placed exactly like the second mark, except on the
maxillary left first molar.
Figure 3.1 - Construction of horizontal reference plane.
After the horizontal plane was established, a mark was
made at the highest point of contour on the buccal gingival
38
margin of the maxillary central incisor and the adjacent
maxillary canine.
The software then measured the distance
between each mark and the horizontal plane (Figure 3.2).
Figure 3.2 - Measurements from the highest point of contour
on the buccal gingival margin of maxillary central incisor
and maxillary canine to the horizontal reference plane.
There were 3 measurements obtained from the software.
They included: (1) the distance from the buccal gingival
margin of the maxillary central incisor to the horizontal
plane (U1-P), (2) the distance from the buccal gingival
margin of the maxillary canine to the horizontal plane (U3P), and (3) the distance from the distal surface of the
maxillary central incisor to the mesial surface of the
mesial erupted permanent maxillary canine (D-U1/U3).
39
Once these measurements were gathered, the gingival
margin relationship between the maxillary central incisor
and maxillary canine (U1-U3) was calculated by subtracting
U3-P from U1-P.
If U1-U3 was a negative number, the
gingival margin of the canine was more apical than the
gingival margin of the central incisor.
If U1-U3 was a
positive number, the gingival margin of the canine was more
incisal than the gingival margin of the central incisor.
The gingival margin relationship (U1-U3) was further
divided into one of six categories: (1) the gingival margin
of the maxillary canine is apical to the gingival margin of
the maxillary central incisor between 0.01 - 0.50 mm, (2)
the gingival margin of the maxillary canine is apical to
the gingival margin of the maxillary central incisor
between 0.51 – 1.0 mm, (3) the gingival margin of the
maxillary canine is apical to the gingival margin of the
maxillary central incisor by more than 1.0 mm, (4) the
gingival margin of the maxillary canine is incisal to the
gingival margin of the maxillary central incisor between
0.01 - 0.50 mm, (5) the gingival margin of the maxillary
canine is incisal to the gingival margin of the maxillary
central incisor between 0.51 - 1.0 mm, and (6) the gingival
margin of the maxillary canine is incisal to the gingival
40
margin of the maxillary central incisor by more than 1.0
mm.
Statistical Analysis
All of the statistics were calculated using SPSS
software version 20.0 (SPSS Inc., Chicago, Illinois).
Descriptive and frequency statistics were run for U1-P, U3P, and U1-U3 for each quadrant.
Non-parametric Mann-
Whitney U tests were run to compare the gingival margin
relationship between the maxillary central incisor and the
mesial erupted maxillary canine for left vs. right sides
and for male vs. female.
The significance level was set at
an alpha of 0.05.
Reliability
All of the measurements were made by the same
examiner.
In order to assess intra-examiner reliability,
approximately 10% of the total sample was chosen to be remeasured.
A random number generator from random.org
selected 10 quadrants to be re-measured.
Measurement
reliability was determined using Cronbach’s alpha.
41
Results
Using Cronbach’s alpha for intra-examiner reliability,
all of the variables were above 0.80, showing that the
original measurements and repeated measurements were at an
acceptable level of reliability for accuracy of
measurements.
The average distance from the distal surface of the
permanent maxillary central incisor to the mesial surface
of the mesial erupted permanent maxillary canine (D-U1/U3)
in the right quadrants was 1.18 mm.
the average was 1.26 mm.
In the left quadrants,
The overall average of both
quadrants was 1.22 mm, with a range of 0.0 – 3.84 mm.
Table 3.1 reports the descriptive statistics for the
parameters used in this study.
Tables 3.2 and 3.3 show the
descriptive statistics for the parameters of the right and
left quadrants.
Table 3.1: Descriptive statistics for U1-P, U3-P, and U1U3.
Parameter
N
Range
Min
Max
Mean
Std. Dev
U1-P (mm)
81
4.98
0.90
5.88
3.22
1.10
U3-P (mm)
81
5.97
0.14
6.11
2.83
1.23
U1-U3 (mm)
81
4.96
-1.76
3.20
0.39
1.09
42
Table 3.2: Descriptive statistics for U1-P, U3-P, and U1-U3
of the right quadrants.
Parameter
N
Range
Min
Max
Mean
Std. Dev
U1-P (mm)
41
3.64
1.24
4.88
3.20
1.08
U3-P (mm)
41
4.62
0.68
5.30
2.82
1.24
U1-U3 (mm)
41
4.20
-1.10
3.10
0.38
1.13
Table 3.3: Descriptive statistics for U1-P, U3-P, and U1-U3
of the left quadrants.
Parameter
N
Range
Min
Max
Mean
Std. Dev
U1-P (mm)
40
4.98
0.90
5.88
3.23
1.14
U3-P (mm)
40
5.97
0.14
6.11
2.84
1.24
U1-U3 (mm)
40
4.96
-1.76
3.20
0.39
1.06
Figure 3.3 summarizes the gingival margin relationship
between the maxillary central incisor and maxillary canine
(U1-U3).
Of 81 maxillary canines, compared to the
maxillary central incisor, the gingival margin for 33
(40.70%) of them was apical to the gingival margin of the
central incisor and 48 (59.30%) of them were incisal.
Of
the 33 that were apical, 15 (18.50%) were 0.01 - 0.50 mm
apical, 10 (12.30%) were 0.51 – 1.0 mm apical, and 8
(9.90%) were greater than 1.0 mm apical to the gingival
margin of the central incisor.
43
Of the 48 that were
incisal, 12 (14.80%) were 0.01 - 0.50 mm incisal, 17
(21.00%) were 0.51 – 1.0 mm incisal, and 19 (23.50%) were
greater than 1.0 mm incisal to the gingival margin of the
central incisor.
70.00%
Canine Relationship
to Central Incisor
59.30%
60.00%
50.00%
40.00%
40.70%
%
23.50%
> 1.0 mm
9.90%
0.51 - 1.0 mm
30.00%
12.30%
21.00%
0.01 - 0.50 mm
20.00%
10.00%
18.50%
14.80%
0.00%
Apical to central Incisal to central
incisor
incisor
Figure 3.3 - Maxillary canine gingival margin relationship
to the maxillary central incisor gingival margin.
Figure 3.4 compares the gingival margin relationship
of the maxillary central incisor and maxillary canine (U1U3) between the left and right sides.
There were a total
of 41 quadrants on the right side and 40 on the left.
44
50.00%
46.30%
45.00%
40.00%
35.00%
35.00%
30.00%
26.80%
25.00%
25.00%
20.00%
Left Side
20.00%
20.00%
17.10%
Right Side
15.00%
9.80%
10.00%
5.00%
0.00%
Apical to central
incisor
0-0.5 mm incisal
0.5-1 mm incisal
> 1 mm incisal
Figure 3.4 - Maxillary canine gingival margin relationship
to the maxillary central incisor gingival margin: Left vs.
Right quadrants.
Tables 3.4 and 3.5 show the descriptive
statistics for the parameters of the male and female
quadrants.
Table 3.4: Descriptive statistics for U1-P, U3-P, and U1-U3
of the male quadrants.
Parameter
N
Range
Min
Max
Mean
Std. Dev
U1-P (mm)
39
4.47
1.41
5.88
3.14
1.23
U3-P (mm)
39
5.16
0.14
5.30
2.61
1.19
U1-U3 (mm)
39
4.19
-1.09
3.10
0.54
1.14
45
Table 3.5: Descriptive statistics for U1-P, U3-P, and U1-U3
of the female quadrants.
Parameter
N
Range
Min
Max
Mean
Std. Dev
U1-P (mm)
42
4.39
0.90
5.29
3.29
0.98
U3-P (mm)
42
5.43
0.68
6.11
3.04
1.25
U1-U3 (mm)
42
4.96
-1.76
3.20
0.25
1.03
Figure 3.5 compares the gingival margin relationship
of the maxillary central incisor and maxillary canine (U1U3) between males and females.
There were a total of 39
male quadrants and 42 female quadrants.
50.00%
45.00%
40.00%
42.90%
38.50%
35.00%
30.80%
30.00%
23.80%
25.00%
20.00%
16.70%
17.90%
Male
16.70%
Female
12.80%
15.00%
10.00%
5.00%
0.00%
Apical to central
incisor
0-0.5 mm incisal
0.5-1 mm incisal
> 1 mm incisal
Figure 3.5 - Maxillary canine gingival margin relationship
to the maxillary central incisor gingival margin: Male vs.
Female quadrants.
46
The Mann-Whitney U test failed to show any
statistically significant difference with relation to
gender (p-value of 0.343) or left/right side (p-value of
0.788) for gingival margin relationship between the
maxillary central incisor and the mesial erupted permanent
maxillary canine.
Discussion
The purpose of this study was to determine, in
patients who are congenitally missing permanent maxillary
lateral incisors, if the natural gingival margin
relationship between the maxillary central incisor and the
more mesial erupted maxillary canine is similar to the
natural gingival margin relationship between the maxillary
central incisor and the maxillary lateral incisor.
Multiple authors in the literature suggest that the
gingival margins of the central incisors should be at the
same level as the canines, with those of the lateral
incisors positioned more incisal.12,
16-18, 23, 24
However, it
is important to keep in mind that this is only their expert
opinion of what the ideal gingival margin relationship is,
not what it naturally is, and that none of these studies
directly measured the natural relationship between the
47
gingival margins of the maxillary central and lateral
incisors.
Many of these authors formed their opinion based
on surveys where people ranked photographs of the smile,
with only the gingival margin relationship between the
maxillary central and lateral incisors being altered.16-19
Other studies did actually measure the gingival margin
relationship between the maxillary central and lateral
incisor, either directly on plaster casts using digital
calipers or indirectly using computer software and digital
photographs of plaster casts.20,
21
Chu et al had a sample of 20 patients in which they
measured directly on plaster casts the gingival margin
relationship between the maxillary central and lateral
incisors.21
They found the gingival margin of the maxillary
lateral incisor on average to be about 1 mm (0.94 mm on the
right side and 0.95 mm on the left side) incisal to that of
the maxillary central incisor.
In the present study, the
gingival margin of the mesial erupted maxillary canine was
found to be on average about 0.39 mm (0.38 mm on the right
side and 0.39 mm on the left side) incisal to the gingival
margin of the maxillary central incisor.
Charruel et al investigated 103 patients using
computer software and digital photographs of plaster casts
to obtain measurements of the gingival margin relationship
48
between the maxillary central and lateral incisors.20
They
found the gingival margin of the maxillary lateral incisor
on average to be 0.68 mm incisal to the gingival margin of
the maxillary central incisor.
This is closer to the
finding of the present study (0.39 mm incisal) than what
Chu et al found in their study.21
Charruel et al also found in their study that about
four percent of maxillary lateral incisors had their
gingival margin apical to the gingival margin of the
maxillary central incisor, 15% were at the same level, 54%
were between 0.0 – 1.0 mm incisal, and 27% were greater
than 1.0 mm incisal.20
In the present study, 40.7% of mesial erupted
maxillary canines were found with the gingival margin
apical to the gingival margin of the maxillary central
incisor, 35.8% were between 0.0 – 1.0 mm incisal, and 23.5%
were greater than 1.0 mm incisal.
The present study found
a much higher percentage of maxillary canines with a
gingival margin more apical than that of the maxillary
central incisor.
This could be due to the fact that in
previous studies, they had an extra category in which to
place the gingival margin relationship.
This category was
for maxillary lateral incisors that had the gingival margin
at the same level as the gingival margin of the maxillary
49
central incisors.
The problem lies in that they didn’t
specify how close the gingival margins had to be in order
to be included in that category and excluded from the
categories above and below it.
In the present study, not
one sample was exactly on the same level. Some were very
close, but they were categorized as either apical or
incisal to the maxillary central incisor.
It is also
possible that in the study by Charruel et al, some of the
15% of maxillary lateral incisors that were categorized as
on the same level as the maxillary central incisor could be
placed in either the 0.0 – 1.0 mm incisal category or the
apical to the central incisor category, increasing the
percentages of those categories and bringing them closer to
the percentages found in the current study’s 0.0 – 1.0 mm
(35.8%) and apical to the central incisor (40.7%)
categories.20
In the studies by Chu et al and Charruel et al, their
samples did not exclude patients that had orthodontic
treatment previously.20,
21
By not making that part of the
exclusion criteria, one is able to question the validity of
their results because they didn’t really look at the
natural relationship between gingival margins of maxillary
central and lateral incisors.
If some of their sample had
50
orthodontic treatment previously, then the measurements on
those specific patients shouldn’t be considered natural.
In a study by An et al, previous orthodontic treatment
was one of their exclusion criteria.19
They examined 120
dental students and found 14.60% of gingival margins of
maxillary lateral incisors to be apical to the gingival
margins of maxillary central incisors, 25.90% were at the
same level, and 59.40% were incisal.
The present study had
a similar finding, in that it found 59.30% of gingival
margins of mesial erupted maxillary canines to be incisal
to the gingival margins of maxillary central incisors.
Again, by not specifying how close the gingival
margins had to be to each other in order to be included in
the “same level” category, one may assume that some of the
25.9% could actually be placed in either of the other two
categories, increasing those percentages as well, which
could make their findings more similar or different to
those in the present study.
The current study was similar to other studies in that
it found no significant difference with relation to gender
or left/right side for gingival margin relationship between
the maxillary central incisor and a mesial erupted
maxillary canine.20,
21
51
The results from the present study suggest that the
gingival margin relationship between the permanent
maxillary central incisor and a mesial erupted permanent
maxillary canine should be included as another criterion in
each doctor’s protocol when treatment planning patients who
are congenitally missing a permanent maxillary lateral
incisor.
One of the limitations of the study was the small
sample size (n=81 quadrants).
Another limitation was the
age of the patients in the sample.
Because the sample
consisted of patients between 10 – 18 years of age, there
is always the possibility of tooth eruption affecting the
gingival margins.
The results from this study are grounds for new
investigations in which the gingival margin relationships
between the normally erupted permanent maxillary central
incisor, maxillary lateral incisor, and maxillary canine
can be compared to the missing permanent maxillary lateral
incisor side.
52
Conclusions
Based on the results of this study, one can conclude
that:
1) Mesial erupted permanent maxillary canines in
adolescents who are congenitally missing permanent
maxillary lateral incisors have a gingival margin that
is apical to the gingival margin of the permanent
maxillary central incisor 40.70% of the time, and
incisal to the gingival margin of the permanent
maxillary central incisor 59.30% of the time.
2) There is no significant difference with relation to
gender or left/right side for gingival margin
relationship between the maxillary central incisor and
a mesial erupted maxillary canine.
53
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56
VITA AUCTORIS
Gregory William Carr was born on July 02, 1980 in Salt
Lake City, Utah to Michael and Carole Carr.
He is the
youngest of four siblings.
He grew up in Bountiful, Utah graduating from Viewmont
High School in 1998. He then attended Ricks College for one
year on a baseball scholarship before moving to The
Philippines for two years to serve a mission for The Church
of Jesus Christ of Latter-day Saints.
Upon returning home,
he attended Ricks College for one more year and then
transferred to Brigham Young University where he graduated
in 2005 with a B.S. in Biology.
After college, he attended
Temple University’s Kornberg School of Dentistry for his
dental education and received his D.M.D. in 2011. He plans
to receive his M.S. and certificate in Orthodontics from
Saint Louis University in 2013.
Dr. Carr met his wife Jenna while attending Brigham
Young University and they were married on January 18, 2005
in Salt Lake City, Utah. They have three children: Brinley,
Julianne, and McKay.
57