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PERIODONTOLOGY
ISSNO906-6713
DAVID A. GARBER & MAURICE
1996
2000
A. SALAMA
Until recently, dentists' and the public's concept of
dental aesthetics was necessarily limited to alterations of the teeth themselves. Dentists concerned
themselves with changing the position, the shape
and the color of the teeth -basically restoring
missing units or enhancing those already present.
For the most part the dentist was forced to accept
the pre-existing relationship between the three
components of the smile; the teeth, the gingival
scaffold and the lips.
Interestingly, the restorative dentist's concept of
aesthetics varied considerably from that practiced
by removable prosthodontists where, in the full
denture set-up, they could not only select the most
desirable shape and color of denture tooth
concomitant with the patient's facial features but
could position them in the optimal relationship
with regards to the upper lip, the lower lip and the
commissures of the mouth -thereby creating the
desired ideal smile.
The three basic tenets germaine to optimal
aesthetics in removable prosthetics were not really
a part of the restorative dentist's rules, as any
changes in the pre-existing lip-tooth-gingival
relationships were thought to necessitate longterm orthodontic therapy, often in combination
with
orthognathic
surgery
or
aggressive
periodontal procedures. Today much of this has
changed; with the advent of soft tissue periodontal
plastic
procedures
designed to
enhance
dentofacial harmony following the same basic
tenets as those of the removable prosthodontist.
The domain of periodontics has changed from
being strictly a health service to one where smile
enhancement has been brought to the forefront of
treatment planning.
The essentials of a smile involve the
relationships
between the three primary
components:
.the teeth
.lip framework
.the gingival scaffold.
The teeth
The dentist is concerned with the color, the position, and the shape or silhouette form of teeth. The
advent of adhesive dentistry has allowed literally
an instantaneous change in the color, the shape
and the position of teeth via bonding techniques
such as porcelain laminate veneers and direct
composite bonding.
The gingival
scaffold
The primary objective of periodontal therapy is to
restore and maintain the health and integrity of the
attachment apparatus. From an aesthetic perspective this is often not enough. An irregular gingival
arrangement, despite being healthy, may strike a
discordant note, and it may become desirable to
establish a certain harmony and continuity of form
to the free gingival margin. In its broadest sense,
this would require that the gingival architecture for
the two central incisors mimic one another. For the
lateral incisors, one would like to see these gingival
margins somewhat more incisally placed and, for
the most part, bilaterally symmetrical. The cus-
I Table 1. Methods
of developing
gingival
harmony
Orthodontics
Surgery
Additive
gingival techniques
Resective gingival techniques
Extrusion
Intrusion
pids, in turn, would have the free gingival margin
at the same level of the centrallncisors and match ing one another. Extending distally, the tissues on
the premolars would be somewhat coronally positioned (1,9).
Periodontic plastic procedures, such as the basic
gingivectomy, soft tissue grafting or the apically
positioned flap, may be used to change the
silhouette form of teeth and their relative
proportion.
To develop this symmetry, both surgical and
orthodontic procedures might be used (Table I).
Surgical
techniques
Additive techniques for augmenting gingiva have
evolved from the early free gingival grafts through
the many different forms of contiguous grafting.
This would include pedicle grafts, connective tis-
Fig. 2. Postoperative view following semilunar graft displaying optimally developed gingival symmetry
Fig. 3. Postorthodontic case showing excessivedisplay of
gingival tissue below the inferior border of the upper lip.
This is a caseof altered passive eruption, which should be
differentiated from vertical maxillary excess.The short,
rather squat teeth and hyperplastic tissue usually indicate
an altered passive eruption case. Compare this with the
postoperative result in Fig. 5 where the gingiva line falls
just below the inferior border of the upper lip.
Fig. 4. Periodontal probing showing the amount of tissue
readily removed without compromising the biological
width. A basic gingivectomy/gingivoplasty is therefore the
procedure of choice.
Fig. I. Preoperative view showing gingival recession of the
maxillary left central incisor. This is the only apically notated gingival margin showing an overall lack of harmony.
Fig. 5. The case following a gingivectomy showing normally proportioned teeth with a decreasein the amount of
gingival display just below the border of the upper lip.
19
Garber
& Salama
sue grafting, semilunar techniques, coronally positioned grafts and guided tissue regeneration (Fig. 1,
2) (2, 3, 5, 7, 8, 10, 11, 13, 14).
Resective techniques involve both the basic
gingivectomy with or without gingivoplasty, as well
as the full flap procedure incorporating osseous
removal for crown lengthening of one or more
teeth (Fig. 3-5).
The medium lipline in western culture is
deemed to be the most attractive. When the patient
smiles, a nominal exposure of 1 to 3 mm of gingiva
from the most apical extent of the free gingival
margin to the inferior border of the upper lip is
exposed. Thus the teeth in their entirety are on
display as well as the interdental gingival tissue
and the border of free gingiva around the cervical
area of the tooth.
Orthodontic techniques
The great advantage in moving teeth orthodontically is that the entire attachment apparatus, incorporating the osseous structure, periodontalligaments and the soft tissue components, moves together with the tooth. This means that, in health,
during an extrusive movement, the free gingival
margin will move coronally at the same distance as
the incisal edge moves (Fig. 6) .Concomitantly, the
osseouslevel will move an identical distance in the
same direction.
From an aesthetic perspective, this means that
any intrusive or extrusive tooth movement can be
used to develop symmetry of the gingival margin in
a nonsurgical mode (Fig. 7-9). This is particularly
useful when any form of restoration is necessary,as
a surgical procedure invariably exposes root
structure, where the mesiodistal dimension of the
tooth is now considerably narrower (Fig. 10). In
attempting to restore this, it becomes necessary to
prepare the tooth and the tissue in such a way that
an emergence profile can be developed from deep
within the sulcus to avoid lateral horizontal
extensions from the preparation line on the
narrower root surface to the desired wider form of
the restoration. If there is a dramatic diminution of
the mesiodistal width of the root at the original
gingival level versus the desired level, then
orthodontics may be the treatment of choice.
The lips
The lips form the frame of a smile and as such, define the aesthetic zone. Liplines have classically
been defined as being high, medium or low (6).
In the typical low lipline, only a portion of the
teeth are exposed below the inferior border of the
upper lip.
The high lipline shows a large expanse of gingiva
extending from the inferior border of the upper lip
to the free-gingival margin.
20
The geometry
of harmony
Within the confines of th~ lipline, the remaining
two components of the smile need to be arranged
in such a way as to develop a c~rtain continuity of
form, harmony and balance (Fig. 11). Classically,
the prosthodontist would like to set up a denture
so that the level of the gingival margins of the maxillary teeth parallel the form of the upper lip. The
incisal edges of these maxillary teeth tend to follow
the form of the lower lip. In a transverse dimension, the teeth should extend progressively posteriorly and laterally to fill the vestibule extending to
the corners of the smile. In the composition of a
beautiful smile, the form, balance, symmetry and
relationship of the elements make it attractive or
unattractive. An expanse of soft tissue should not
be considered to be unaesthetic per se,but the way
this soft tissue is arranged relative to the teeth and
lips is of aesthetic concern. Continuity of linear
horizontal form between the gingival expanse, the
teeth and the upper lip is critical. Any asymmetry
in this parallelism disturbs the sense of balance in
the composition, disturbing the flow and results in
an unaesthetic smile (Fig. 12).
By this definition, a high lipline in itself may not
be unaesthetic if these basic rules are followed.
However, in today's mass media-influenced
culture, many people consider eventhe slightest
excessive display of gingival tissue -the "gummy
smile" -unattractive.
The gummy smile or high lipline case with an
expanse of soft tissue can result from two basic
problems:
.altered
.vertical
passive eruption
maxillary excess.
The definitive diagnosis of the problem determines
the treatment.
One of the clinical criteria in determining which
of these two factors is responsible for a" gummy
Principles of aesthetic diagnosis
Fig. 6. Orthodontic clinical eruption sequence showing
how movement of the left central incisor in an incisal direction results in a concomitant change in the level of the
free gingival margin aswell as the osseouscrest
Fig. 7. Preoperative smile showing compensatory overeruption of the maxillary central incisors as a result of a
long-term anterior bruxing pattern. Note the unaesthetic
change in gingival line as compared with the drape of the
upper lip
Fig. 8. Orthodontic appliance is in position showing the use
of an intrusive archwire. The stainless steel archwire in a
passive position lays in the manllary anterior vestibule.
When ligated to the central incisor brackets, it exerts an intrusive force.
Fig. 9. Postorthodontic result showing alignment of the
gingiva on the two central incisors without harming the
adjacent teeth. No surgery was performed in this situation.
Compare with Fig. 7.
Fig 10. Computer simulation showing restorative differential in preparation of caseswhere the gingival harmony is
restored with orthodontic intrusion versus surgical crown
lengthening
21
Garber & Salama
Fig. II. Computer simulation showing a smile with the various components in harmony. The incisal edgeline follows
the form of the lower lip -while the line joining the tops of
the free gingival margins form the upper lip. The teeth bilaterally extend to fill the vestibules to the commissures of
the lips.
Fig. 12.A preoperative maxillary anterior reconstruction in
place showing the lack of harmony between the various
components of the smile, the teeth, the lips, and the gingiva. The gingival line is diametrically opposed before the
maxillary arch. Note the harmony developedin the postoperative case between the lips, the teeth, and the gingival
scaffold.
Fig. 13.Preoperativeview showing rather short, squat teeth
in which the height is inadequate relative to the width. Periodontal bone-soundingvia the sulcus indicates that there is
22
a large dimension between the free gingival margin and the
cementoenamel junction, as well as spacebetween cementoenamel junction and the osseouscrest for insertion of the
biological width. The green line on the teeth is indicative of
the preoperative level of the free gingival margin.
Fig. 14. A gingivectomy was performed to elevate the level
of the free gingival margin -developing a more proportion ate form for the teeth, aswell as removing an excessivedisplay of gingiva below the inferior border of the upper lip.
Fig. 15. Postoperative healing of the gingivectomy as well
as orthodontic repositioning of the right central incisor
without closing the diastema provides for bonding in equal
amounts between the two central incisor without closing
the diastema.
Fig. 16. Preoperative view of smile showing short nonproportionate teeth as well as an excessivedisplay of gingiva.
Principles of aesthetic diagnosis
smile " relates to the basic shape of the teeth. If the
teeth appear to be somewhat short and squat meaning that the vertical dimension appears to be
too short as compared with the horizontal
dimension, the gummy smile is probably due to
altered passive eruption.
If, however, the silhouette form of the tooth
appears to be normal and an expanse of tissue is
exposed below the inferior border of the upper lip,
this is probably due to an overgrowth of the maxilla
in a vertical dimension or a vertical maxillary
excess.
In many situations, the gummy smile may be a
combination of these two factors.
The
gummy
.
smile
altered
passive
eruptIon
Altered passive eruption is an aberration in normal
development where a large portion of the anatomic crown remains covered by the gingiva. This
complicates developing dentofacial harmony for
two dominant reasons:
.The tissue being positioned coronally on the
teeth results in a silhouette form that is unattractive. There is only a nominal degree of scallop to
the free gingival margin, resulting in a tooth
shape that is somewhat square instead of a more
attractive elliptical or ovoid form.
.The excess soft tissue tends to be displayed
below the inferior border of the upper lip, complicating the desired relationship in that it makes
a potentially medium lipline into a high lip line.
Altered passive eruption has been classified into
two distinct types (4).
In type I, there is typically an excessive amount
of gingiva, as measured from the free gingival
margin to the mucogingival junction.
In type II, there is a normal dimension of gingiva
when measured from the free gingival margin to
the mucogingival junction. Although these might
appear to be clinically similar in that there is tissue
extended over the coronal portion of the tooth,
therapeutically the diagnosis between the two
types is essential to determine the appropriate
treatment modality.
Type I can be further subdivided on an
anatomical histological basis into sub-categories A
and B. This subclassification depends on the
relationship of the osseous crest to the
cementoenamel junction
of the tooth. In
subcategory A, the dimension between the level of
the cementoenamel junction and the osseous crest
is greater than 1 mm, which is sufficient for the
insertion of the connective tissue fibrous
attachment component of the biological width. In
subcategory B, detected by the process of bone
sounding via the sulcus, the osseous crest occurs in
close proximity to the cementoenamel junction,
thereby diminishing the space for the insertion of
the connective tissue of the biological width.
The biological width, which comprises the
junction epithelium, the connective tissue fibrous
attachment and the sulcus, is co~sidered to be an
inviolate parameter. This implies that the
biological width should not be impinged upon by
restorative endeavors. Based on early necropsy
studies, the average dimensions of the biological
width were considered to be approximately 2.7 mm
-about 1 mm for the junctional epithelium, 1 mm
for the connective tissue attachment and 1 mm for
the sulcus. In clinical practice, we have found this
to be a more varied dimension often exceeding the
3 mm average.
Treatment of type I -altered passive eruption
The typical case of altered passive eruption type I A exhibits short, square-Iooking teeth and an expanse of gingiva below the inferior border of the
upper lip. A needle probing of the osseous crest
through the gingival sulcus detects a distance between the cementoenamel junction and the osseous crest that is sufficient to maintain the biological width (Fig. 13). A gingivectomy using scalpel,
electrosurgery or carbon dioxide laser will readily
remove this tissue. The tissue should be removed
cervically in order not to compromise the interdental papillae. This procedure will result in a revised silhouette form for the tooth (Fig. 14) that is
more elliptical and attractive and will resolve the
unwarranted excessivedisplay of gingiva apparent
during smiling (Fig. 15).
Altered passive eruption -type I-B
Diagnosis is confusing in this subcategory, as the
clinical appearance is similar, with an excessive
amount of gingiva from the free gingival margin to
the mucogingival junction readily shown during
smiling (Fig. 16). On bone sounding via the sulcus,
it would appear that the osseous crest is at the
23
Garber & Salama
Fig. 17. The bone-sounding process viewed by making a
submarginal incision, leaving the free gingival margin in
place while elevating mucoperiosteal full-thickness flaps.
With a probe in place, the dimension from the free gingival
margin to the cementoenamel junction and level of the osseouscrest is evident.
Fig. 18.The osseoushas been redevelopedapically with the
form following and paralleling the rise and fall of the cementoenamel junctions typical of this genetic phenotype.
Fig. 19. The flaps coapted and sutured in position just incisal to the cementoenamel junction
Fig. 20. Following initial healing of the flap procedure, a
gingivectomy/gingivoplasty is performed as part of the
two-stage procedure using electrosurgery to fine-tune the
harmony of the free gingival margin, ensuring the pres-
24
ence of interdental papillae and realigning the gingival
margin optimally, not with the cementoenamel junction,
but with the drape of the upper lip.
Fig. 21. Postoperative early healing of the case following
the second stage of electrosurgery. Compare with Fig. 16
and note the more proportionate teeth as well as the diminished amount of gingival display.
Fig. 22. Lateral oblique view of a patient with vertical maxillary excessin combination with altered passiveeruption.
The green line on the gingiva indicates the extent of the required gingivectomy to develop gingival harmony as well
as optimal tooth proportion. The black lines on the incisal
edgesdenote the tooth structure to be removed in cosmetic
contouring to develop ideal embrasure form and incisal
edgeline.
Principles of aesthetic diagnosis
The sounding with a probe tends to identify the
more incisally positioned outer cortical plate. The
proximity of the osseous crest to the cementoenamel junction requires surgical relocation of the
soft tissue apically via reduction of the osseous
crest (Fig. 18, 19) (1, 5) to allow for insertion of
these fibers in a more coronal position followed by
a concomitant apical positioning of the junctional
epithelium and the sulcus. This ultimately results
in the free gingival margin being positioned right at
the cementoenamel junction. The surgical procedure, however, may require modification depending on the relative position of the upper lip to the
cementoenameljunction (Fig. 20, 21).
Altered passive eruption -type II
same level as the cementoenamel junction. This
would seem to be contrary to the concept of the biological width, as the connective tissu~ fibrous at tachment cannot insert into the enamel and yet
must be present (Fig. 17).Clinical and histological
necropsy observations suggest that, in altered passive eruption type I- B, there is an added dimension
buccolingually to the osseous form. This extra
thickness to the osseous structure allows for an
apical angulation of the bone crest from the gingi val aspect of the periodontal ligament side. Although periodontal connective tissue fibers normally run horizontally across the osseous crest extending from the cementum to the gingiva, in this
form of altered passive eruption, the fibers run apically' parallel to this angular crest, allowing for insertion of the connective tissue fibers just apical to
the cementoenamel junction in the cementum.
In altered passive eruption type II, the pathognomonic short teeth are clinically evident, but the
zone of masticatory mucosa is not excessive as in
type I. This then requires reduction apically of the
entire dentogingival complex, with or without osseous reduction, to aesthetically solve the aesthetic
problem.
The gummy
smile
maxillary
excess
-vertical
The gummy smile frequently results from a skeletal
dysplasia (Fig. 22)I such as a hyperplastic growth of
the maxillary skeletal base. This results in the teeth
being positioned farther away from the skeletal
maxillary base and a display of gingiva below the
inferior border of the upper lip. Diagnosis in the
high lipline case involving a vertical maxillary excessrequires ruling out the casesdue to a superim-
Table 3. Treatment of the gummy smile: altered passive eruption or vertical maxillary excess
Condition
Treatment options
Altered passive eruption type I-B
Flap with osseous resection
Vertical maxillary
excess -degree
2
Periodontics
Orthognathic
and restorative
surgery
dentistry
Garber & Salama
26
Principles of aesthetic diagnosis
Fig. 23. The gingivectomy is performed with the CO2laser
on the upper right side, but contrasted to the left side. This
is done prior to any orthognathic surgery to give the surgeon a more precise guideline as to the degreeof impaction
required during his procedures.
Fig. 24. The patient following the orthognathic procedures.
This depicts the patient with lips at rest showing a nominal
amount of incisal edge as well as a full smile. The degreeof
vertical translation of the lip between the rest and full
smile is the required dimension of a tooth to eliminate any
show of gingiva. This, however,may result in an excessively
long tooth. The lip at rest is the limitation to vertical impaction for the orthognathic surgeon, as any further impaction will result in no show of incisal edge at rest and a
more aged appearance for the patient. Here, following orthognathic procedures, there is still a show of gingiva below the inferior border of the lip in full smile view.
Fig. 25. To eliminate this postorthognathic surgery show of
tissue, the patient elected to have further periodontal surgery to lengthen the teeth -eliminating the gingiva. The
green dot on the teeth is indicative of the cementoenamel
junction to which the original gingivectomy was done.
Now the osseousstructures redeveloped in a more apical
level and the flap repositioned further apically to display
more tooth structure.
Fig. 26. Postoperative early healing showing the relocated
gingiva line following bleaching of these teeth and cosmetic contouring of the incisal edgesabove the mandibular teeth.
Fig. 27. A preoperative view of the completion of the orthodontic phase prior to orthognathic surgery.
Fig. 28. The postoperative view following gingivectomy, orthognathic procedure, surgical crown lengthening, bleaching, and cosmetic contouring 5 years following completion
of the case.
Fig. 29. The implant site optimally developed showing a
continuity of form of the free gingival margin, aswell as the
three-dimensional reconstruction of the papillae and root
eminence.
Fig. 30. Postoperativeview of the lateral incisor and restoration in place. Note harmony with the rest of the natural
teeth, but supported by the soft tissue reconstruction to
make it indistinguishable from the adjacent dentition.
position of altered passive eruption in combination with maxillary hyperplasia. These combined
cases should first be treated for any altered relationship between gingiva and cementoenamel
junction (Fig. 21). This results in the development
of a more aesthetic tooth silhouette form and allows for more accurate diagnosis. Orthognatic procedures can take place to reposition the maxilla.
The combined casesrequire for optimal treatment
a multidisciplinary approach to treatment planning involving an orthodontist, a periodontist, an
orthognathic surgeon and a restorative dentist.
Table 4. Desirable traits of an attractive smile
Teeth
color
position
silhouette
shape
Gingiva
Lips
define the aesthetic zone
three forms ofliplines: high, medium, and low
the geometry of harmony
gingival line follows upper lip contour
incisal edge line follows lower lip form
The classification of vertical maxillary excess
(Tables 2, 3) was developed to help determine the
most appropriate treatment modality. The
diagnosis relative to the degree of severity is
predicated upon first treating the altered gingival
display (removing the altered passive eruption
component) and to develop a normal tooth form
(crown form). Degrees of severity I, II and III are
then determined by the amount of remaining
gingiva displayed. The treatment modalities range
from orthodontic intrusion alone through complex
treatments
involving
orthognathic
surgery,
orthodontics,
restorative
components
and
periodontal plastic procedures.
In vertical maxillary excess cases degrees II and
III involving orthognathic surgery, the treatment
planning relates to developing the relationship
between the incisal edge and the lip at' rest. In
some combination cases,the vertical translation of
the lip from rest to its position at maximal smile
may, in fact, exceed the normal length of a tooth
crown. As such, patients must decide whether to
accept a nominal display of gingiva below the
upper lip and normal crown dimensions or to
prefer an increased length of the crowns and no
display of gingiva.
It is critical in these casesto treat to the position
of the lip at rest, as otherwise the surgeon may
overimpact the maxilla, burying the incisal edge
beyond the vermilion border of the lip -resulting
in a dramatically aged appearance.
In combination cases,the diagnostic procedural
treatment is as follows:
27
Garber
& Salama
.First create an attractive silhouette form for the
teeth developing normal anatomical form. This
will remove any altered passive eruption component from the case,leaving only the vertical maxillary excess or skeletal dysplasia evident. It also
gives the surgeon a definitive guideline as to the
potential lip-to-tooth relationships and the
amount of impaction necessary (Fig. 23).
.The orthognathic procedure is limited by the
incisal edge to lip at rest position. A minimum of
2.0 mm of the incisal edge of the teeth should be
showh at rest; that is, the maxilla is not to be
impacted beyond this level (Fig. 24).
.Following orthognathic impaction, any remaining gingival display may be removed as determined by the patient's subjective needs by using
a periodontal flap with osseousresection accomplished in a two-stage approach. The flap should
first be replaced and sutured at its original position, and following initial healing, sculpted with
electrosurgery to develop optimal silhouette
tooth form, thereby retaining the interdental
papillae (Fig. 25-28) .
Diagnosis for total dentofacial aesthetics today involves a comprehensive knowledge of the desired
smile composition as determined by its three basic
elements: the teeth themselves, the gingival scaffold and the lip framework. Developing these relationships about the three basic tenets of a beautiful
smile incorporates:
.adhesive dentistry
.a multidisciplinary
integrated approach
.implants.
When implants form part of the treatment plan, the
basic tenets relevant for removable prosthodontics
and conventional restorative work remain identical. The high lip line is thus the most difficult for clinicians to deal with, because it exposes to the onlooker any restorative work. In any implant case,the
basic arrangement of the various components of
the smile -the teeth, the lips, and the gingival scaffold -must first be made harmonious prior to developing the individual implant receptor sites with
the identical configuration to conventional teeth;
that is, an interdental papilla on each side with a
rise and fall to the free gingival margin in between
and the illusion of a root eminence -all in harmony
with the contralateral teeth (Fig. 29, 30) (Table 4).
28
Summary
As the public becomes increasingly concerned
with looking younger and healthy, aesthetic considerations will become increasingly more relevant
in dental treatment planning. As such, dentists
must define the basic tenets of an aesthetic smile extending that vision beyond simply "pretty teeth "
to a concept whereby total dentofacial harmony is
developed. Aesthetics is not simply a matter for restorative dentists -it uses restorative dentistry as
one of the disciplines, but it is about beauty. The
same rules that apply for a denture are therefore
pertinent for crown and bridge and/ or implants
and must be applied in all aesthetic endeavors.
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