Periodo11tology2000, Vol. 11,1996, 18-28 Printed in Denmark. All rights reserved

Copyr ight 0 Munksgaard 1996

PERIODONTOLOGY 2000 ISSN 0906-6713

The aesthetic smile: diagnosis and treatment DAVID A. GARBER & MAURICE A. SALAMA

Until recently, dentists’ and the public’s concept of dental aesthetics was necessarily limited to alter- ations 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 long- term 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 posi- tion, 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 perspec- tive 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-

_ _ _ _ _ _ ~

Table 1. Methods of developing gingival harmony

Surgery Orthodontics Additive gingival techniques Extrusion Resective gingival techniques Intrusion

~~ - -

18

Principles of aesthetic diagnosis ~~

pids, in turn, would have the free gingival margin at the same level of the central incisors and match- ing one another. Extending distally, the tissues on the premolars would be somewhat coronally posi- tioned (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 1).

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 dis- playing optimally developed gingival symmetry Fig. 3. Postorthodontic case showing excessive display of gingival tissue below the inferior border of the upper lip. This is a case of 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 gingivectomylgingivoplasty is therefore the procedure of choice. Fig. 5. The case following a gingivectomy showing nor- mally proportioned teeth with a decrease in the amount of gingival display just below the border of the upper lip.

Fig. 1. Preoperative view showing gingival recession of the maxillary left central incisor. This is the only apically no- tated gingival margin showing an overall lack of harmony.

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Garber & Snlama

sue grafting, semilunar techniques, coronally posi- tioned 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).

Orthodontic techniques

The great advantage in moving teeth orthodonti- cally is that the entire attachment apparatus, in- corporating the osseous structure, periodontal lig- aments and the soft tissue components, moves to- gether 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 osseous level 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, de- fine 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.

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.

The geometry of harmony

Within the confines of the lipline, the remaining two components of the smile need to be arranged in such a way as to develop a certain 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 max- illary 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 dimen- sion, the teeth should extend progressively posteri- orly 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 passive eruption vertical 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

20

Primiples of aesthetic diagnosis . ~-

Fig. 6. Orthodontic clinical eruption sequence showing how movement of the left central incisor in an incisal di- rection results in a concomitant change in the level of the free gingival margin as well as the osseous crest

Fig. 7. Preoperative smile showing compensatory overe- ruption 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 maxillary anterior vestibule. When ligated to the central incisor brackets, it exerts an in- trusive 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 differen- tial in preparation of cases where the gingival harmony is restored with orthodontic intrusion versus surgical crown lengthening

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Fig. 11. Computer simulation showing a smile with the var- ious components in harmony. The incisal edge line follows the form of the lower lip - while the line joining the tops of the free gingival margins form the upper lip. The teeth bi- laterally 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 gin- giva. The gingival line is diametrically opposed before the maxillary arch. Note the harmony developed in the postop- erative case between the lips, the teeth, and the gingival scaffold.

Fig. 13. Preoperative view showing rather short, squat teeth in which the height is inadequate relative to the width. Peri- odontal bone-sounding via the sdcus indicates that there is

a large dimension between the free gingival margin and the cementoenamel junction, as well as space between cemen- toenamel junction and the osseous crest 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, as well as removing an excessive dis- play 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 nonpro- portionate teeth as well as an excessive display of gingiva.

22

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 ana- tomic 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 unattrac- tive. 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, com- plicating the desired relationship in that it makes a potentially medium lipline into a high lipline.

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 11, 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 considered 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-looking teeth and an ex- panse of gingiva below the inferior border of the upper lip. A needle probing of the osseous crest through the gingival sulcus detects a distance be- tween the cementoenamel junction and the 0s- seous crest that is sufficient to maintain the biolog- ical 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 inter- dental papillae. This procedure will result in a re- vised silhouette form for the tooth (Fig. 14) that is more elliptical and attractive and will resolve the unwarranted excessive display 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

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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 os- seous crest is evident.

Fig. 18. The osseous has been redeveloped apicallywith the form following and paralleling the rise and fall of the ce- mentoenamel junctions typical of this genetic phenotype.

Fig. 19. The flaps coapted and sutured in position just in- cisal to the cementoenamel junction Fig. 20. Following initial healing of the flap procedure, a gingivectomylgingivoplasty is performed as part of the two-stage procedure using electrosurgery to fine-tune the harmony of the free gingival margin, ensuring the pres-

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 di- minished amount of gingival display. Fig. 22. Lateral oblique view of a patient with vertical max- illary excess in combination with altered passive eruption. The green line on the gingiva indicates the extent of the re- quired gingivectomy to develop gingival harmony as well as optimal tooth proportion. The black lines on the incisal edges denote the tooth structure to be removed in cosmetic contouring to develop ideal embrasure form and incisal edge line.

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Principles of aesthetic diagnosis - _ _ _ _ _ _ _ ~ ~ ~

Table 2. Vertical maxillary excess classification

Degree mucosal display Treatment modalities I 2-4 mm Orthodontic intrusion only

Gingival and

Orthodontics and periodontics Periodontics and restorative

I1 4-8 mm Periodontics and restorative therapy

therapy

_

Orthognathic surgery The choice depends on the remaining amount of root encased in bone and crown-to- root ratio

without adjunctive periodon- tal and restorative therapy complete dentofacial harmony

I11 28mm Orthognathic surgery with or

_ _

same level as the cementoenamel junction. This would seem to be contrary to the concept of the bi- ological width, as the connective tissue fibrous at- tachment cannot insert into the enamel and yet must be present (Fig. 17). Clinical and histological necropsy observations suggest that, in altered pas- sive 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. Al- though periodontal connective tissue fibers nor- mally run horizontally across the osseous crest ex- tending from the cementum to the gingiva, in this form of altered passive eruption, the fibers run api- cally, parallel to this angular crest, allowing for in- sertion of the connective tissue fibers just apical to the cementoenamel junction in the cementum.

The sounding with a probe tends to identify the more incisally positioned outer cortical plate. The proximity of the osseous crest to the cementoe- name1 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 proce- dure, however, may require modification depend- ing on the relative position of the upper lip to the cementoenamel junction (Fig. 20,21).

Altered passive eruption - type I1

In altered passive eruption type 11, the pathogno- monic 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 os- seous reduction, to aesthetically solve the aesthetic problem.

The gummy smile - vertical maxillary excess

The gummy smile frequently results from a skeletal dysplasia (Fig. 22), 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 ex- cess requires ruling out the cases due to a superim-

Table 3. Treatment of the gummy smile: altered passive eruption or vertical maxillary excess

_ ~ __ Condition Altered passive eruption type 1-A Altered passive eruption type 1-B Vertical maxillary excess - degree 1

-

_ _ _ _

- ____ Vertical maxillary excess - degree 2

_ _ _ _ Vertical maxillary excess - degree 3

'Ikeatment options Gingivectomy Flap with osseous resection Orthodontics Orthodontics and periodontics Periodonties Periodontics and restorative dentistry Periodontics and restorative dentistry Orthognathic surgery Orthognathic surgery plus periodontics and restorative dentistry where necessary

- __. -

_ __

- __________ -

_ _

_ ___ __ __ -

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Garber & Salama _.__

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Principles of aesthetic diagnosis

Fig. 23. The gingivectomy is performed with the CO, laser on the upper right side, but contrasted to the left side. This is done prior to any orthognathic surgery to give the sur- geon a more precise guideline as to the degree of 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 degree of 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 im- paction for the orthognathic surgeon, as any further im- paction will result in no show of incisal edge at rest and a more aged appearance for the patient. Here, following or- thognathic procedures, there is still a show of gingiva be- low 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 sur- gery 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 osseous structures 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 cos- metic contouring of the incisal edges above the mandibu- lar teeth.

Fig. 27. A preoperative view of the completion of the orth- odontic phase prior to orthognathic surgery.

Fig. 28. The postoperative view following gingivectomy, or- thognathic procedure, surgical crown lengthening, bleach- ing, 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, as well as the three-dimensional reconstruction of the papillae and root eminence. Fig. 30. Postoperative view of the lateral incisor and resto- ration 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 combina- tion with maxillary hyperplasia. These combined cases should first be treated for any altered rela- tionship between gingiva and cementoenamel junction (Fig. 21). This results in the development of a more aesthetic tooth silhouette form and al- lows for more accurate diagnosis. Orthognatic pro- cedures can take place to reposition the maxilla. The combined cases require for optimal treatment a multidisciplinary approach to treatment plan- ning involving an orthodontist, a periodontist, an orthognathic surgeon and a restorative dentist.

Table 4. Desirable traits of an attractive smile Three teeth components gingiva

Teeth color lips

position silhouette shape

harmony and continuity of form symmetry central incisors balance to laterals, cuspids and premolars as determined by lip drape

Lips define the aesthetic zone three forms of liplines: high, medium, and low the geometry of harmony gingival line follows upper lip contour incisal edge line follows lower lip form

Gingiva health

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, I1 and I11 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 I1 and I11 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 cases to 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:

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First create an attractive silhouette form for the teeth developing normal anatomical form. This will remove any altered passive eruption compo- nent from the case, leaving only the vertical max- illary 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 shown at rest; that is, the maxilla is not to be impacted beyond this level (Fig. 24). Following orthognathic impaction, any remain- ing gingival display may be removed as deter- mined by the patient's subjective needs by using a periodontal flap with osseous resection accom- plished in a two-stage approach. The flap should first be replaced and sutured at its original posi- tion, 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 in- volves a comprehensive knowledge of the desired smile composition as determined by its three basic elements: the teeth themselves, the gingival scaf- fold and the lip framework. Developing these rela- tionships 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 identi- cal. The high lipline is thus the most difficult for cli- nicians to deal with, because it exposes to the on- looker any restorative work. In any implant case, the basic arrangement of the various components of the smile - the teeth, the lips, and the gingival scaf- fold - must first be made harmonious prior to de- veloping 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).

Summary

As the public becomes increasingly concerned with looking younger and healthy, aesthetic con- siderations 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 re- storative 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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