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2009;140;1160-1166 J Am Dent Assoc

Frank SpearAnterior Tooth ReplacementImplants or Pontics: Decision Making for

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1160 JADA, Vol. 140 http://jada.ada.org September 2009

PERSPECTIVES CLINICAL DILEMMAS

Science has provided

today’s restorative

dentist with continu-

ally improving tools for

the replacement of

missing teeth, and providing

esthetically pleasing outcomes

for single missing anterior teeth

is a highly predictable procedure

in the hands of most clinicians.

The predictability decreases

substantially when significantbone and soft tissue also have

been lost; however, even in this

scenario, a competent interdisci-

plinary team generally can pro-

duce an acceptable result by

using an implant or a fixed par-

tial denture with an ovate pontic

to replace the missing tooth.

When the loss is not of one tooth

but of numerous teeth, particu-

larly if those teeth are adjacent

to each other, the esthetic chal-

lenge is immensely morecomplex.

As implants have improved

and placement techniques have

evolved to take advantage of

those improvements, the

informed clinician may gravitate

toward use of implants as the

preferred solution for all missing

teeth. As implant science con-

tinues to improve, the use of

fixed partial dentures may

become an anachronism, much

like the specialized preparations

of hemisectioned molars re-

quired in perioprosthodontics.

At one time, the technique for

creating these unusual prepara-tions was taught in every dental

school; today, it is a lost art.

Fortunately, the loss is realized

only in situations in which bone

grafting, implant placement or

both are impossible—an ever-

decreasing occurrence. Although

it may be preferable to have a

“root” wherever a tooth is

missing, the esthetic challenges

presented by multiple missing

anterior teeth often require the

combination of implants andovate pontics to achieve accept-

able esthetic results.

The average papillary height

above bone between natural

teeth is 4.5 millimeters.1,2 When

a single-tooth implant is placed,

papillary levels are determined

by the height of the bone on the

adjacent natural teeth, not by

that of the bone around the

implant.3-5 Therefore, the papil-

lary height between a tooth and

an implant will be similar to

what it was before tooth

removal. The facial gingival

margin around the implant is

related to the bone levels on theimplant, as well as to the thick-

ness and position of the free gin-

gival margin before tooth

removal.6,7

SINGLE MISSING ANTERIORTEETH

The least predictable soft-tissue

outcome with a single anterior

implant is associated with inter-

proximal bone loss in the adja-

cent natural teeth. Because

interproximal bone determinespapillary height, creating

esthetic papillary heights can be

difficult. If the newly edentulous

space is to receive not an

implant but rather a pontic as

part of a fixed partial denture,

the bone level on the teeth adja-

cent to the space still will deter-

mine the papillary heights.

Implants or ponticsDecision making for anterior tooth replacement

Frank Spear, DDS, MSD

Copyright © 2009 American Dental Association. All rights reserved. Reprinted by permission.



JADA, Vol. 140 http://jada.ada.org September 2009 1161

PERSPECTIVES C L I N I C A L D I L E M M A S

The most significant differ-

ence between a pontic and an

implant is that the clinician can

significantly alter the soft tissue

that will surround a pontic and

create a papilla by means of soft-tissue grafting procedures.

When the clinician places a soft-

tissue graft, the amount of

tissue above the bone between a

pontic and a natural tooth, or

between a pontic and an

implant, averages 6.5 mm—an

increase of 2.0 mm, or 44 per-

cent. In some patients, the

tissue height after grafting can

be as high as 9.0 mm.8

When natural teeth adjacent

to a single edentulous spacehave bone loss, soft-tissue ridge

augmentation followed by place-

ment of a pontic always will

achieve greater coronal papil-

lary height than will a single-

tooth implant placed into the

edentulous space. In a situation

in which the papilla, to be

esthetically acceptable, must be

more than 4.5 mm above the

level of the bone, placement of a

fixed partial denture with anovate pontic is the most appro-

priate treatment decision.

MULTIPLE MISSING ANTERIOR TEETH

When multiple teeth are

missing or require removal, the

soft-tissue ramifications are dif-

ferent because of the biology of

the periodontium and the

responses of the bone and soft

tissues. To understand these

ramifications, it is helpful toconsider the biological response

of the soft tissue after tooth

removal. In a case involving the

removal of two central incisors,

the interproximal bone height

on the lateral incisors will deter-

mine the papillary height be-

tween the lateral incisors and

whatever is placed in the space.

The soft tissue on the mesial

side of the lateral incisor will act

exactly as it would in the case of

a single-tooth replacement. The

facial free gingival margin

height in each central incisorsite also will be similar in

response to a single missing

tooth. The facial bone level and

tissue thickness will determine

the height at which the facial

gingival margin stabilizes. The

difference between the single

edentulous space and the space

created by removal of the two

central incisors is what happens

to the papilla that existed

between them before the

extractions.9,10

If we assume no periodontaldisease existed before tooth

removal, the osseous crest

around both central incisor sites

will follow the scalloped form of

the cementoenamel junction.

The gingiva on the facial bone

will be positioned so that, on

average, the free gingival

margin is 3.0 mm coronal to the

osseous crest. As the cemento-

enamel junction flows from the

facial aspect into the interprox-

imal aspect, the bone follows,and an average osseous scallop

of 3.0 mm is created. Because

soft tissue follows the scallop of

the bone, the osseous scallop

presumably should result in a

gingival scallop of 3.0 mm. How-

ever, when teeth are present, an

interesting phenomenon occurs:

the papilla is 1.5 mm more

coronal to the osseous crest than

to the facial tissue. This addi-

tional 1.5 mm added to the

3.0-mm average osseous scallop

results in the tip of the papilla’s

matching the 4.5-mm averagenoted previously (Figure 1). The

restorative challenge created by

the loss of both central incisors

relates directly to the osseous

scallop that existed between

those incisors.

Replacement of the central

incisors with two single

implants adjacent to each other

is one of the prosthetic restora-

tive options available. During

placement, the clinician places

the implant apically until theplatform is level with the facial

osseous crest. Most implants in

use today are not scalloped;

because the bone is scalloped,

the interproximal platform of

the implant may be apical to the

interproximal osseous crest by

as much as 3.0 mm. Although

implant placement retains bone

that would be lost if the site

remained edentulous, a certain

amount of bone adjacent to theimplant is expected to resorb

across time, usually to the level

of the first thread of the

implant.11,12 Resorption of the

interproximal osseous crest

results in a flattening of the

osseous crest. Maintaining a

minimum distance of 3.0 mm

between implants seems to

lessen this flattening, but

researchers agree that, regard-

less of the distance between

implants, the crestal boneundergoes some degree of

resorption and flattening.13

The visible and esthetic issue

in these osseous changes is the

corresponding flattening of the

gingival architecture. Tarnow

and colleagues13 identified a

papillary height of 4.5 mm above

bone between two adjacent teeth

The restorative challenge

created by the loss of both

central incisors relatesdirectly to the osseous

scallop that existed

between those incisors.






and of 4.5 mm above bone

between a natural tooth and anadjacent implant. With the

placement of adjacent implants,

papillary height between the

implants changes from 4.5 mm

to between 3.0 and 3.5 mm

above the bone.13 This change

represents a dramatic and

potentially devastating esthetic

challenge to the replacement of

teeth with implants. Even if the

interproximal osseous crest

could be maintained perfectlybetween two implants, the

papilla will stabilize 1.0 to 1.5

mm apical to where it was

between the teeth simply

because of the change in soft-

tissue levels above the bone

(Figure 2). Adding this 1.0- to

1.5-mm difference to the osseous

changes affecting the interprox-

imal crestal bone height makes

it clear why maintenance of an

esthetically correct papillary

height between adjacentimplants is such a difficult

proposition.

The use of pontics to replace

the two central incisors involves

its own challenges.14,15 The soft

tissue between the central

incisor pontics and the lateral

incisor abutments, as well as the

facial soft tissue, will behave as

described above when a pontic

replaces a single tooth. The chal-lenge is the papilla between the

adjacent pontics, just as it is

between adjacent implants. The

interproximal crestal bone be-

tween the extracted central

incisors will resorb, creating a

flat bony ridge with subsequent

loss of potential papillary

height. This esthetic challenge

differs from that posed by the

implants because of the ability

to augment the soft-tissueheight above the flattened os-

seous crest between the lateral

incisors to an average 6.5 mm.

MAKING AN APPROPRIATEDECISION

Thorough evaluation, careful

diagnosis of the existing condi-

tion and a clear understanding

of the responses of the hard and

soft tissues provide a basis for

predicting treatment outcome.

The following manifestationsare the four most common

esthetic dilemmas created by

multiple missing teeth.

dThe teeth are present and

need to be removed; there is no

periodontal disease affecting the

teeth to be removed.

dThe teeth are present and

need to be removed; there is

periodontal disease affecting the

teeth to be removed.dThe teeth are missing and the

osseous and soft-tissue ridge are

flattened; the free gingival

margin location on the ridge is

acceptable as a papillary

position.

dThe teeth are missing and the

osseous and soft-tissue ridge are

flattened; the free gingival

margin is positioned signifi-

cantly apically to an acceptable

papillary position.With knowledge of the usual

behavior of the bone and soft

tissue, we can discuss each of

the four manifestations and

select the most appropriate

treatment.

Tooth removal and re-

placement in the absence of

periodontal disease. The most

predictable situation is one in

which the patient requires

removal of multiple teeth in the

absence of periodontal disease.The challenges in this situation

are related first to the choice

between implants and a fixed

partial denture and, second, if

implants are chosen, how many

should be placed and where. The

appropriate choices depend on

which teeth are being removed.

For example, if the two maxil-

Figure 1. The average osseous scallop is 3.0 millimeters from thefacial aspect to the interproximal aspect, and the average gingivalscallop is 4.5 mm from the facial aspect to the interproximal aspectbetween natural teeth.

Figure 2. When adjacent implants are placed 3.0 or more millime-ters apart and the facial and interproximal osseous crest is retained(red lines), the papilla between the implants may be within 1.0 to1.5 mm of the original papillary height (yellow line).






lary central incisors are being

removed and they are supported

by healthy bone, placing adja-

cent implants can result in a

predictable and esthetic final

result. The papilla between thecentral incisor implants and the

adjacent lateral incisors will be

excellent, the facial gingival

margins can be augmented

easily, if required, and the

papilla between the central

incisor implants should remain

within 1.0 to 2.0 mm of the pre-

extraction papillary level if the

clinician places the implants

3.0 mm apart and most of the

interproximal osseous crest is

maintained (Figure 3). The clini-cian could treat this same

patient with a fixed prosthesis

by using the lateral incisors as

abutments. Since the interprox-

imal bone between the extracted

central incisors most likely will

be lost, the risk of soft-tissue

recession in the area in which a

papilla needs to be created

between central incisor pontics

is an esthetic challenge. As

described previously, soft-tissueaugmentation before completing

the restoration creates signifi-

cant tissue height that could be

used to form an excellent papilla

between the pontics.

When the teeth to be removed

involve a central incisor and a

lateral incisor, or a lateral

incisor and a canine, the treat-

ment choices become much less

clear. The difficulty encountered

is twofold. First, placement of

adjacent implants in the centralincisor and lateral incisor sites,

or the lateral incisor and canine

sites, is difficult if the surgeon is

to maintain a minimum of 3.0

mm between the platforms of

the implants. This situation

means there is a high risk that

interproximal osseous crest will

be lost between the implants

across time, with subsequent

loss of papillary height (Figure

4). Second, when papillary

height is lost between the cen-

tral incisor and lateral incisor

on one side while natural teeth

exist on the other side, the dis-

crepancy in papillary height ismuch more noticeable than a

slight loss of papillary height in

the middle of the face between

adjacent central incisor im-

plants. These reasons—combined

with the fact that use of adja-

cent implants to replace a cen-

tral incisor and a lateral incisor,

or a lateral incisor and a canine,

is not required for force manage-

ment in the anterior aspect—

make placement of a single

implant in the site of the centralincisor or the canine, with a can-

tilever replacing the lateral

incisor as an ovate pontic,

esthetically more predictable

and functionally acceptable.

An alternative for prosthetic

replacement of a missing central

incisor and lateral incisor or lat-

eral incisor and canine is sur-

gical soft-tissue augmentation

and placement of a fixed partial

denture. Although this method

can create a pleasing esthetic

result, it is a much more com-

plex restoration structurally and

functionally, particularly when

the lateral incisor and thecanine are being replaced by

pontics.

When removal of three or four

adjacent anterior teeth with

good periodontal support is

required, my preference is place-

ment of implants separated by

one or two pontics. If both cen-

tral incisors and one lateral

incisor need to be removed, I

would choose placement of one

implant in the proximal central

incisor site, placement of a cen-tral incisor ovate pontic and

placement of the second implant

in the lateral incisor site. This

design allows the creation of

excellent papillary heights in all

locations because of the pre-

dictability of the soft-tissue aug-

mentation in the ovate pontic

site (Figure 5).

Figure 3. A. A patient who required the extraction of both central incisors. Note theexcellent bone level and papillary height. B. Because the interproximal osseous crest wasmaintained and the soft tissue supported at the time of tooth removal, an excellent interim-plant papilla exists. C. Final restorations exhibit minimal change in papillary height whencompared with pre-extraction height. Even in this ideal situation, the difference is 1.0 to 1.5millimeters apically. Photographs courtesy of Dr. Greggory Kinzer.

A

B

C






If removal of all four incisors

is required and good periodontal

support exists, the clinician has

two equally acceptable options

for implant prostheses. One is

placement of implants in both

lateral incisor locations, with

the replacement of both central

incisors as ovate pontics. The

second is placement of the

implants in the central incisor

locations with a mediating space

of at least 3.0 mm; the lateral

incisor ovate pontics then can be

cantilevered from the central

incisors. Both options produce

acceptable esthetic, structural

and functional results.

Tooth removal and re-

placement in the presence of

periodontal disease. Consid-

ering the same manifestationsdiscussed previously, but adding

the presence of pre-existing bone

loss resulting from periodontal

disease, provides new chal-

lenges. Foremost among these is

the loss of predictability of the

papillary height after tooth

removal in the areas of peri-

odontal disease. When peri-

odontal disease is present, the

bone does not always respond as

it would if it were healthy,

which often leads to greaterresorption of bone and a greater

degree of papillary recession.

Therefore, to avoid an open gin-

gival embrasure, the clinician

must position contacts more api-

cally than is esthetically desir-

able. The clinician is left with

the challenge of using implant

restorations that will be accept-

able functionally and struc-

turally but less so esthetically,

or of forgoing the use of implants and using soft-tissue

grafting with fixed partial den-

tures in areas in which grafting

and pontics can produce signifi-

cantly more soft tissue over the

interproximal bone. The differ-

ence between tissue heights of

3.5 and 6.5 mm above bone can

be the difference between an

esthetic success and an esthetic

failure. The final decision about

which modality is best suited for

success will be based on theesthetic requirements created by

the lip line and mobility and the

condition of the remaining teeth.

If the adjacent teeth are unre-

stored, it may be preferable to

conserve tooth structure by

using implants rather than

preparing unrestored teeth.

Some esthetic compromise may

Figure 4. A. Adjacent implants placed in central and lateral positions. Note excellent inter-proximal bone but minimal interimplant distance. B. At insertion, no black triangle waspresent; however, six months after insertion, papilla has receded as bone is lost. C. Twelvemonths after implant placement, soft tissue has migrated apically as bone between theimplants has continued to resorb.

A

B

C

A B

C D

Figure 5. A. A patient with three ankylosed teeth but with excellent bone levels.B. Teeth nos. 8, 9 and 10 were removed and immediate implants placed at no. 8 andno. 10. C. Connective-tissue grafting in pontic area no. 9 and over implant no. 10. D. Finalrestoration after grafting: a three-unit zirconia prosthesis consisting of an implant abutment

at no. 8, a pontic at no. 9 and an abutment at no. 10.






be in the patient’s best interest

and should not be dismissed

without serious consideration

and discussion.

Slow orthodontic eruption

before extraction is anotheroption to consider when it is

necessary to remove multiple

adjacent teeth with periodontal

disease.15 Although eruption of a

single tooth that is to be ex -

tracted does not alter the final

papillary heights, because those

heights are dictated by the bone

on the adjacent teeth, the erup-

tion of multiple teeth before

extraction may move interprox-

imal bone coronally. This move-

ment of the bone is not highlypredictable, however, so the

clinician must inform the

patient that a perfect esthetic

result is unlikely and that short

papillae, long contacts and more

rectangular final restorations

could be expected (Figure 6).

Tooth replacement in the

presence of a flattened ridge.

The final two manifestations,

both involving a flattened ridge,

are the most difficult to manageesthetically. When multiple

teeth are removed, the bony

ridge tends to flatten rapidly

unless the clinician does some-

thing to alter the process. In

cases in which the teeth have

been missing for a significant

time, the interproximal osseous

crest will be gone completely.

Recreating vertical bone height

in situations in which multiple

teeth have been removed is diffi-

cult and unpredictable. For thisreason, when the teeth are

missing before any treatment,

use of adjacent implants results

in inadequate papillary height.

Using a connective graft and

pontics, however, can create and

maintain significantly more soft

tissue above the interproximal

bone than is possible with adja-

cent implants. Therefore, the

clinician must inform the

patient that the best esthetic

result may involve pontics

rather than implants in some

sites. Selection of the most

appropriate sites for using

connective-tissue grafting and a

pontic next to an implant will

minimize esthetic compromises

and can achieve an excellent

esthetic result (Figure 7).

CONCLUSION

Patients who have multiple

missing anterior teeth, or

patients for whom removal of

multiple anterior teeth is

Figure 6. A. A patient requiring extraction of teeth nos. 8 and 9 because of extensivebone loss. Note excellent papillary levels. B. Significant bone loss has occurred, creating anesthetic dilemma regarding soft-tissue position. C. Orthodontic eruption was used toattempt to move the bone coronally. D. After the eruption, there has been minimal if anyimprovement. E. Implant placement. F. Final restorations. Note the minimal gingival scallopcaused by an apically placed papilla and a long contact. This esthetic compromise wasexpected owing to the patient’s significant interproximal bone loss before implant place-ment. Photographs courtesy of Dr. David Mathews and Dr. Vince Kokich.

A

B

C

D

E F






required to restore dental

health, bring with them signifi-

cant issues in ensuring an

acceptable esthetic result.

Careful evaluation of the bone

available; the periodontal healthwhen teeth are still present; the

amount of tooth displayed

during normal activities; the

functional and structural

requirements of the restora-

tions; and the patient’s esthetic

concerns, demands and expecta-

tions will lead the dentist and

the patient through a thera-

peutic decision tree, each branch

requiring a choice. This series of

thoughtful choices ultimatelyensures that the clinician will

achieve the best solution for

each patient. The solution may

include compromises in the

interest of giving greater impor-

tance to a portion or portions of

the desired outcome, but they

will be compromises made with

the full knowledge and under-

standing of all parties. In the

end, investing the time, thought

and communication necessary to

make the right choice createstwo beautiful smiles—in a

pleased patient and a happy

dentist. ■

Dr. Spear is the founder and director,Seattle Institute for Advanced Dental Educa-tion, 600 Broadway, Suite 490, Seattle, Wash.98122. Address reprint requests to Dr. Spear.

Disclosure. Dr. Spear did not report anydisclosures.

The views expressed are those of the authorand do not necessarily reflect the opinions orofficial policies of the American Dental Association.

The author thanks Dr. Greggory Kinzer forthe photographs in Figure 3; Dr. DavidMathews and Dr. Vince Kokich for the pho-tographs in Figure 6; and Dr. David Mathewsfor the photographs in Figure 7.

1. Tarnow DP, Magner AW, Fletcher P. Theeffect of the distance from the contact point tothe crest of bone on the presence or absence of

the interproximal dental papilla. J Periodontol1992;63(12):995-996.2. van der Velden U. Regeneration of the

interdental soft tissues following denudationprocedures. J Clin Periodontol 1982;9(6):455-459.

3. Choquet V, Hermans M, Adriaenssens P,Daelemans P, Tarnow DP, Malevez C. Clinicaland radiographic evaluation of the papillalevel adjacent to single-tooth dental implants:a retrospective study in the maxillary anteriorregion. J Periodontol 2001;72(10):1364-1371.

4. Grunder U. Stability of the mucosal topog-raphy around single-tooth implants and adja-cent teeth: 1-year results. Int J PeriodonticsRestorative Dent 2000;20(1):11-17.

5. Kan JY, Rungcharassaeng K, Umezu K,Kois JC. Dimensions of peri-implant mucosa:an evaluation of maxillary anterior single

implants in humans. J Periodontol 2003;74(4):557-562.6. Kois JC. Predictable single-tooth peri-

implant esthetics: five diagnostic keys. Com-pend Contin Educ Dent 2004;25(11):895-896,898, 900.

7. Smukler H, Castellucci F, Capri D. Therole of the implant housing in obtaining aes-thetics: generation of peri-implant gingivaeand papillae—part 1. Pract Proced Aesthet

Dent 2003;15(2):141-149.8. Salama H, Salama MA, Garber D, Adar P.The interproximal height of bone: a guidepostto predictable aesthetic strategies and softtissue contours in anterior tooth replacement.Pract Periodontics Aesthet Dent 1998;10(9):1131-1141.

9. Elian N, Jalbout ZN, Cho SC, Froum S,Tarnow DP. Realities and limitation in themanagement of the interdental papillabetween implants: three case reports. PractProced Aesthet Dent 2003;15(10):737-744.

10. Saadoun AP, Le Gall MG, Touati B. Cur-rent trends in implantology, part II: treatmentplanning, aesthetic considerations, and tissueregeneration. Pract Proced Aesthet Dent 2004;16(10):707-714.

11. Hermann JS, Cochran DL, NummikoskiPV, Buser D. Crestal bone changes around

titanium implants: a radiographic evaluationof unloaded nonsubmerged and submergedimplants in the canine mandible. J Periodontol1997;68(11):1117-1130.

12. Hermann JS, Buser D, Schenk RK,Cochran DL. Crestal bone changes aroundtitanium implants: a histometric evaluation of unloaded nonsubmerged and submergedimplants in the canine mandible. J Periodontol2000;71(9):1412-1424.

13. Tarnow DP, Cho SC, Wallace SS. Theeffect of inter-implant distance on the heightof inter-implant bone crest. J Periodontol2000;71(4):546-549.

14. Spear FM. Maintenance of the inter-dental papilla following anterior toothremoval. Pract Periodontics Aesthet Dent1999;11(1):21-28.

15. Salama H, Salama M, Kelly J. The ortho-

dontic-periodontal connection in implant sitedevelopment. Pract Periodontics Aesthet Dent1996;8(9):923-932.

Figure 7. A. A patient with a significant ridge defect and previously placed adjacent implants in the lateral and canine position.B. The lateral incisor implant has been covered with soft tissue rather than used and the canine implant uncovered after soft-tissue grafting.C. The final restoration: the lateral incisor is now cantilevered off of a canine implant. Photographs courtesy of Dr. David Mathews.

A B C


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