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5 Factors that Influence Soft Tissue Aesthetics

5 Factors that Influence Soft Tissue Aesthetics

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5  Soft Tissue Management for Implants in the Aesthetic Zone



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Triangular



Ovoid



Square



Thin - High Scallop



Average - Medium Scallop



Thick - Flat Scallop



Fig. 5.5 (a) Triangular-shaped teeth typically present with highly scalloped gingiva and tall interproximal papilla height. (b) Ovoid-shaped teeth will present with an average gingival scallop and

an average interproximal papilla height. (c) Square-shaped teeth tend to present with a shallow

gingival scallop and short interproximal papilla height



5.5.1 Tooth Shape, Position, and Proximity

Tooth shape influences the interproximal space and the resultant interdental papilla

height. The overall gingival architecture varies from relatively flat, short papillae

between square-shaped teeth to highly scalloped, tall papillae between triangular-­

shaped teeth (Fig. 5.5). Tall, thin papillae are particularly vulnerable to loss when

manipulated and/or when teeth are lost.

Tooth position influences the soft tissue contours. Gingival margins of teeth that

are prominent (labial) in the arch will tend to be thinner, positioned more apical,

and will be more susceptible to recession. Similarly, gingival margins in patient

with a thin biotype will tend to be more susceptible to recession, whereas teeth that

are more palatal in position will tend to have thicker labial tissue, and the gingival

margins will be less susceptible to recession. Likewise, gingival margins in a

patient with a thick biotype will be more resistant to recession of the gingival

margin.

The normal approximation and contact between adjacent maxillary anterior

teeth form a pyramidal-shaped space that is occupied by interdental papilla. The

base of the pyramid is supported by the interproximal crestal bone and bordered

by the cervical contours of adjacent teeth with the papilla peak rising coronal up

to the contact point. Again, the interproximal tissues, adjacent to teeth, are supported coronal to the bone crest by connective tissue fibers inserting into the

cementum on the root surfaces. If adjacent teeth are crowded, in close approximation or possibly overlapping one another, the interproximal space may be diminished or absent causing the papilla to be blocked out. Conversely, when adjacent

teeth are separated by >2.4 mm, the papilla will be less likely to fill the interproximal space [5]. In a study evaluating the effect of interproximal distance on papilla

presence, the authors reported that the interproximal papilla was always deficient

when the interproximal distance between roots was >4.0 mm [6]. When there is a

diastema, the interproximal soft tissues will be flat (Fig. 5.6). This phenomenon



102

Fig. 5.6  Adjacent teeth

that are not in close

proximity fail to form the

typical pyramid-shaped

interproximal space.

Consequently, interdental

tissues remain flat without

a peaked papilla. This case

demonstrates the effect of

a diastema space on the

interproximal tissues. The

tissue is flat when the

interdental space is >4 mm

with diastema



P. R. Klokkevold

Rotated and Prominent



will also be observed when a tooth is missing without a properly contoured prosthetic tooth replacement to support the papilla (Fig. 5.7). On the other hand, when

teeth are replaced with a properly contoured provisional restoration (i.e., pontic),

the interproximal papilla can be maintained (Fig. 5.8).



5  Soft Tissue Management for Implants in the Aesthetic Zone



a



b



c



d



103



Fig. 5.7  Without a properly contoured provisional restoration to support soft tissues, the interproximal papilla height will flatten during the healing period following tooth extraction. (a, b) A

relatively flat veneer is attached with a bracket to the orthodontic arch wire to serve as a temporary

tooth replacement following extraction of the right maxillary central incisor. (c, d) Following about

6 months of healing, the gingival architecture is flattened with loss of papilla height adjacent to the

neighboring teeth. Note the lack of prosthetic contours at the interproximal gingival level



5.5.2 Periodontal Biotype/Bone Support

Periodontal biotype is an important assessment to make when planning implant

placement to replace missing anterior teeth. Maintaining soft tissue aesthetics in

individuals with a thick biotype is fairly predictable. However, maintenance of soft

tissue aesthetics in an individual with a thin biotype is very challenging. Soft tissue

management in patients with thin biotype is critical.

Gingival morphology follows the shape of the underlying bone. It is difficult to

build aesthetically acceptable gingiva in areas with deficient supporting bone.

Bone augmentation is essential when there is moderate to severe loss of tissue

height, especially when implants will be used to replace missing teeth. Soft tissue

augmentation can be used to replace greater volumes in an edentulous (pontic)

space than in areas occupied by implant restorations, especially adjacent implants

(Fig. 5.9) [7].

When considering the surgical placement of implants, clinicians must consider

the approach (conventional two-stage approach versus a one-stage approach) and

the timing of implant placement (immediate versus delayed or staged placement).

For sites that require bone augmentation, the approach may be to bone graft the

ridge first and place the implant(s) after healing, or the simultaneous implant placement and bone graft at the same time. All of these approaches can provide a



104



P. R. Klokkevold



a



b



c



Fig. 5.8  This case shows how the use of a properly contoured provisional restoration (cantilevered ovate pontic) can maintain the interproximal papilla from extraction to 6  months post-­

extraction healing. (a) Maxillary left central incisor #9 extracted without hard or soft tissue

grafting. Note the contours of the interproximal tissues around extraction socket. (b) The site was

allowed to heal with an ovate pontic used to support interproximal tissues. Subsequently, an

implant was placed with a full-thickness flap using a papilla preservation design. The provisional

restoration (cantilevered pontic) was used throughout the posttreatment healing periods. (c) Final

restoration with maintained gingival architecture at 5-year follow-up



Fig. 5.9  Greater soft tissue volume can be created in edentulous ridge “pontic space” than can be

achieved between two adjacent implants. This case shows extraction of a failed endodontically treated

tooth, which is adjacent to an existing restored implant. Radiograph following extraction showing

complete buccal-palatal loss of the bone. Following complete degranulation, the extraction socket was

grafted with particulate bone allograft and a soft tissue graft harvested from the palate. The result is an

edentulous site with substantial tissue thickness that can be shaped to create the appearance of full

interproximal papilla. The site was provisionalized with an ovate pontic that was cantilevered from the

adjacent implant (Restorative treatment by Dr. Edward McLaren, UCLA)



5  Soft Tissue Management for Implants in the Aesthetic Zone



105



successful outcome if patient selection is appropriate and techniques are performed

properly [8–11]. Again, bone support is essential to achieving and maintaining soft

tissue aesthetics.

Wound healing following any surgical intervention will often result in retraction

and recession of soft tissue contours observed as gingival margin recession and loss

of interdental papilla height. For this reason, whenever possible, soft tissue anatomy

should be preserved, and surgical manipulation should be minimized. Papillae are

particularly vulnerable to changes with surgical manipulation. Surgical procedures,

such as papilla preservation techniques, should be used to effectively maintain interproximal tissue height [12–14].

When evaluating soft tissue aesthetics, it is important to recognize that soft tissues are supported by the bone and remaining teeth. Without careful management,

loss of bone and lack of teeth will result in soft tissue deficiency. When a tooth is

lost, the normal process of extraction socket wound healing results in loss of tissue

dimensions. The alveolar socket walls remodel leading to shrinkage of alveolar

dimensions [15]. This is especially true for the horizontal dimension [16, 17]. The

buccal plate is particularly susceptible loss of dimension as part of the normal

remodeling process. Regardless of extraction socket bone graft/preservation techniques, the alveolar dimensions are diminished after tooth extraction. A recent systematic review estimated that the mean horizontal dimension is reduced by 3.8 mm

and the mean vertical dimension is reduced by 1.2 mm within 6 months after extraction [18]. Although the soft tissue dimensions remain fairly consistent before and

after extraction socket remodeling, they are supported by the underlying bone and

therefore tend to be reduced by a similar dimension following tooth loss. The loss

of dimension is greater when the labial bone is very thin or nonexistent, especially

when socket preservation is not performed. Post-extraction management of hard

and soft tissues is critical.

In the absence of teeth, soft tissue contours are only supported by and follow the

contours of the underlying bone. Likewise, when missing teeth are replaced with

dental implants, the soft tissues are primarily supported by and follow the contours

of the bone. Since there are no inserting connective tissue fibers attached to implants

or the restorative components, peri-implant soft tissues rely on supporting the bone

and adjacent teeth. This is why it is virtually impossible to create a full natural

papilla height between implants (see Fig. 5.4). Furthermore, it is important to support soft tissues with provisional restorations such as an ovate pontic during transitional periods of healing prior to implant placement/restoration.

Soft tissue thickness ranges from 1 to 3 mm. Thus, soft tissue height supported

only by underlying bone and implants will generally be limited to 3 mm or less. The

average interproximal papilla height between implants is approximately 3.4 mm,

compared to approximately 4.5 mm between natural teeth [19].



5.5.3 Periodontal Health/Disease

Although it is an obvious statement, it cannot be emphasized enough to state that

periodontal health is essential for the achievement and maintenance of soft tissue

aesthetics. Gingivitis and periodontitis are bacterial-driven inflammatory diseases



106



P. R. Klokkevold



that cause swelling and edema of soft tissues adjacent to contaminated tooth surfaces. Periodontitis, by definition, involves attachment loss and bone loss as well.

Since teeth (and implants too for that matter) are non-shedding, hard structures, a

bacterial biofilm builds on the surfaces especially within the sulcus/pocket in the

absence of proper oral hygiene. Left undisturbed, the biofilm evolves into a pathogenic microflora, which perpetuates a chronic inflammatory response in the tissues.

At the early stages, prior to significant attachment and bone loss, edematous tissues

cover root surfaces and fill interproximal spaces and may give patients a false sense

of “normal” soft tissue contours. However, inflamed tissues are not adherent to

tooth surfaces, tend to bleed easily, and are not stable. They are edematous, easily

retract away from the tooth, and are highly susceptible to recession. Perhaps most

critical to this concern is the fact that when inflammation is resolved and/or when

inflamed tissues are surgically manipulated, they will shrink dramatically resulting

in recession and open interproximal spaces; without a proper assessment, the result

may be unexpected poor soft tissue aesthetics. Periodontal health must be established prior to treatment in order to anticipate and achieve predictable results.



5.5.4 Aesthetic Prognostic Factors

The patient’s chief complaint, aesthetic expectations, tooth positions, gingival form,

osseous crest position, periodontal biotype, tooth shape, and ridge deficiency all

play an important role in deriving an accurate aesthetic treatment plan for the

patient. Therefore, developing the necessary skill and knowledge to examine and

recognize problems of these components is essential to clinical success.

A diagnostic wax-up of the proposed prosthetic restoration as well as a 3D diagnostic scan and implant simulation can be very insightful for visualizing the final

outcome and will shed light on the tissue deficiencies. This assessment will facilitate decision-making and development of the surgical treatment plan.

The most favorable prognostic factors include labial bone that is ≤3 mm from the

desired gingival margin, intact interdental bone height, tooth position that is coronal

and palatal, thick periodontal biotype, and a flat gingival architecture [2, 20]. The

least favorable prognostic factors include loss or lack of labial bone >3 mm from

desired gingival margin and deficient interdental bone height, tooth position that is

apical and facial, thin periodontal biotype, and a highly scalloped gingival architecture (Fig.  5.10) [2, 20]. Greater gingival recession occurs around implants with

labial bone loss [21].



5.6



Techniques for Soft Tissue Augmentation



Many of the techniques for soft tissue augmentation around dental implants have

been adopted from periodontal soft tissue augmentation procedures. Techniques

include free gingival grafts (FGGs), pedicle grafts, subepithelial connective tissue

grafts (SCTGs), and various non-autogenous materials. Flap management may



5  Soft Tissue Management for Implants in the Aesthetic Zone



a



107



b



Fig. 5.10  It is essential to evaluate each patient for his/her presenting circumstances to determine

risk factors and treatment prognosis. (a) Best aesthetic prognosis includes thick periodontal biotype, bone ≤3 mm from gingival margin, high interproximal bone height, relatively flat gingival

architecture, tooth position that is coronal and palatal, and square-shaped teeth. (b) Least favorable

aesthetic prognosis includes thin periodontal biotype, bone >3 mm from gingival margin, reduced

interproximal bone height, highly scalloped gingival architecture with tall papillae, tooth position

that is apical and labial, and triangular-shaped teeth



include coronally advanced flap (CAF), split-thickness flap, or variations of a pouch

procedure. Papilla preservation procedures are essential especially if there is attachment and/or bone loss. Biologics such as enamel matrix derivative (EMD) and

growth factors can be used to enhance healing of soft tissue grafts [22, 23]. More

recently, the use of autologous blood products such as leukocyte- and platelet-rich

fibrin (L-PRF) has been advocated as an adjunct to soft tissue grafting [24].

Free gingival grafts utilize keratinized surface tissue, including the epithelial

layer, harvested from the palate that is transplanted and secured to a prepared recipient site. The epithelial surface is left exposed (i.e., it is not covered by a flap). The

advantage of FGGs is the predictable increase in tissue thickness and zone of keratinized tissue at the recipient site. The aesthetic disadvantage is that FGGs tend to

be distinct and visibly noticeable due to the difference in color from adjacent tissues. FGGs maintain the color of the donor tissue, which may not be aesthetic.

Subepithelial connective tissue grafts (SCTGs) are aesthetically advantageous

because they blend, imperceptibly, with adjacent tissues. SCTGs increase tissue

thickness, especially when placed under the recipient flap. Although SCTGs can be

used as a free graft without overlying flap coverage, this method can be less successful in achieving increased tissue thickness. Thus, SCTGs should be placed under a

flap or into a pouch. Many variations of the flap design have been used to improve

blood supply for SCTGs including full-thickness flap, split-thickness flap, lateral

pedicle flap, double-papilla flap, and pouch techniques to achieve root coverage and

to enhance soft tissue thickness around teeth. Figure 5.11 shows an example of a



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