3]3

Abstract the planning of the periodontal, oc-

clusal, and restorative aspects of the

fixture-assisted dental restoration.

One aim of these new criteria must

be the preparation of a dimensional-

ly adequate and potentially esthetic

recipient site for the implant. Other

important treatment planning consid-

erations include (7) whether any teeth

can be predictably maintained from

a periodontal-prosthetic perspective;

(2) whether any teeth should be ex-

tracted; (3) techniques to augment

the subsequent potential receptor site

when necessary; and (4) the optimal

sequence of implant placement and

mucogingival surgical modalities.

A classification scheme that system-atizes the wide range of regenerativepotential of common extraction sitetopographies is presented. Within thissystem, the parameters for immediateimplant placement and preliminaryridge augmentation are discussed. Inaddition, a new adjunctive role fororthodontic extrusion is introduced.This approach is intended to manip-ulate "hopeless" teeth to modify theirlocal defect environments, therebyenhancing the predictability of sub-

sequent implant placement at thosesites. (Int J Periodont Rest Dent

1993; 13:313-333.)

The Role of OrthodonticExtrusive Remodeling in theEnhancement of Soft andHard Tissue Profiles Prior toImplant Placement:A Systematic Approachto the Management ofExtraction Site Defects

Henry Sa/ama, DMD*Maurice Sa/ama, DMDt

One of the more difficult problems

arises when it is essential or prefer-

able to place an implant at the site

of an existing compromised tooth.

Central to such cases is the question

of how best to manage the residual

defects often associated with the ex-

traction of periodontally hopeless

teeth and to place implants success-

fully at those sites. A complicating

factor is the need to maintain func-

tional and esthetic harmony with ad-

jacent natural teeth. Simple extraction

followed by a healing period of up

to 12 months was recommended as

part of the initial Bronemark proto-

col.5-7 Subsequent bone resorption of

thin labial plates or at the crestal

height of the extraction socket, how-

ever, may result in collapse of a sig-

nificant part of the ridge. A severe

defect may negate the implant op-

tion or prove too compromising in

esthetically strategic areas. Because

the ability to preseNe8 or regenerate

ridges postextraction has increased,9

the original approach seems inade-

quate or, at best, unnecessarily time

consuming.

Osseointegrated dental implants

have enjoyed long-term success in

the rehabilitation of totally edentulous

patients.l-4 Every aspect of traditional

treatment planning protocols contin-

ues to be reevaluated and updated

to better incorporate the benefits of

osseointegration into clinical practice.

This is particularly evident as dentistry

has endeavored to integrate this ap-

proach into the more varied environ-

ment of the partially edentulous pa-

tient.

Along with the many benefits of

added predictability and enhanced

options, the ever-evolving role of os-

seointegrated implants in the treat-

ment of the partially edentulous jaw

has also created new challenges.

This becomes especially apparent

when the periodontal and prosthetic

demands of the periodontally com-

promised patient are incorporated in

the treatment plan.

These challenges have created a

clear need for new criteria to guide

* Assistant Clinical Professar of Periodon-

tics, Periodontal-Prosthesis and Implan-

tologyt Postgraduate Student in Orthodontics

and Periodontics

University of PennsylvaniaSchool of Dental Medicine4001 Spruce StreetPhiladelphia, Pennsylvania 19104

Volume 13, Number 4, 1993

314

movement olso enhances the volume

of the soft tissue by increasing the

zone of attached gingiva.35 This in-

crease occurs because during this

type of movement the gingival mar-

gin migrates coronally while the mu-

cogingival junction remains stable.36

In view of these well-established

processes, we have examined the

role of controlled extrusive tooth

movement as a means by which the

position of the gingival margin and

the bone crest may be shifted co-

ronally prior to tooth extraction. By

addressing isolated deformities in

preparation for implant placement,

this approach may effectively and

uniquely create a greater volume of

available bone and soft tissue in the

vertical plane without surgical inter-

vention.

The purpose of this paper is to in-

troduce a new perspective, one that

utilizes orthodontic extrusion of

"hopeless" teeth to enhance the soft

and hard tissue dimensions of po-

tential implant recipient sites. To set

clear parameters for its application,

this technique will be presented within

the framework of a systematic ap-

proach to managing the extraction

defect environment. Several cases

will be shown to illustrate rationale

and technique.

Techniques that preserve or aug-

ment the ridge at the time of extrac-

tion can eliminate future implant

placement problems and should be

considered when a treatment plan is

developed for a compromised site.

Once extraction defects become es-

tablished over time, however, the

principles of GTR, as they relate to

the augmentation of the buccolingual

osseous dimensions of localized

ridge deformities, may be utilized.18-2°

Nyman et al21 presented a case re-

port wherein an implant site deficient

in .the buccolingual dimension was

augmented, utilizing GTR, prior to im-

plant placement. Buser et al22 also

reported on the osseous augmenta-

tion of short edentulous spans with

an emphasis on creating and main-

taining a space for GTR during heal-

ing.The augmentative techniques pres-

ently available treat the ridge defect

and its ramifications either at the time

of extraction or at a later date. Al-

ternatively, it would be a great ad-

vantage to be able to positively

modify the potential defect environ-

ment before extraction. Success in

such an endeavor may reduce the

need for further augmentative sur-

gical intervention.

The efficacy of extrusive tooth

movement to improve the soft and

hard tissue architecture has been

well documented.23-27 Brown28 and

Ingber29-31 highlighted molar upright-

ing and forced eruption, respectively,

as methods of modifying the osseous

and gingival topography. Since the

gingival fiber apparatus lacks elastic-

ity , stretching it during tooth move-

ment imparts tension to the alveolar

bone. It is widely accepted that this

tension stimulates bone deposition at

the alveolar crest.32-34 Extrusive tooth

Extraction followed by immediate

implant placement has been advo-

cated as a more expedient approach

to replacing hopeless teeth with im-

plants.10-12 This approach incorpo-

rates the principles of guided tissue

regeneration (GTR), a method that

utilizes a barrier membrane to ex-

clude epithelium and connective tis-

sue from the wound site, thereby se-

lectively promoting the ingrowth of

bone around the exposed portion of

the implant. This strategy also de-

mands that there be a certain- mini-

mal amount of engageable. bone at

the apical end of the socket or be-

yond, to stabilize the implant.

While immediate implant place-

ment can be used effectively in many

situations with excellent results, it may

be ineffective in areas where the peri-

odontal breakdown around the

hopeless teeth is particularly severe.

Soft tissue defects, because of sig-

nificant existing recession, can seri-

ously compromise the final esthetic

result. In addition, the potential for

implant instability from a lack of en-

gageable bone in the severely com-

promised ridge may preclude use of

an implant. Where the potential im-

plant receptor sites are thus compro-

mised, alternative approaches must

be employed.

Autogenous grafts have been

used to augment severely atrophic

arches in the vertical and horizontal

dimensions prior to or at the time of

implant placement.13,14 A review of

the literature,15-17 however, indicates

that this technique is extremely re-

source demanding and may be more

useful in the fully edentulous arch

than in areas exhibiting small eden-

tulous spans.

The International journal of Periodontics & Restorative Dentistry

315

Classification and treatment

guidelines

Extraction sites involving compro-

mised teeth exhibit a socket environ-

ment at "the apical end and some

form of extraction defect environment

at the coronal aspect (Fig 1 ). There-

fore, where treatment planning re-

quirements make it necessary to

place implants in the area of an ex-

isting compromised tooth, it can be

anticipated that local deformities of

varying complexity will be encoun-

tered. The criteria for treatment ap-

proaches to sites that are compro-

mised will be discussed based on the

severity of the residual defect envi-

ronment (Fig 2).

The first step to successful treat-

ment planning is the recognition and

classification of the problem(s). We

have formulated a classification sys-

tem that focuses on the residual de-

fect morphology and the regenera-

tive potential at the extraction site.

These guidelines are comparable to

those used to classify periodontal in-

frabony defects.37 The regenerative

potential of an extraction site can

similarly be expected to be related

to the number of osseous walls re-

maining. Accordingly, a socket en-

vironment is defined as being con-

tained within four osseous walls and

having the best regenerative poten-

tial. A defect environment, on the

other hand, has three osseous walls

or fewer and is associated with cor-

respondingly less predictable os-'

seous regeneration around exposed

surfaces of an implant.

Fig 1 Extraction sites of compromised teeth are usually complex and may exhibit differ-ent defect-socket ratios.

Fig 2 A diagnosis prior to extraction is dependent on ascertaining the extent and di-mensions of the defect environment along the root surface. Probing and bone soundingare indispensable.

MODERATE

Volume 13, Number 4, 1993

316

Fig 30 (top left)

Fig 36 (bottom left)

Fig 3c (center)

Fig 3d (right)

Figs 3a to 3d Type 7 extraction sites, such as the ones associated with root fractures, retain a dominant socket environment. The highregenerative potential at these sites makes them ideal for immediate implant placement.

Potential extraction sites can be

very different. Myriad proportions of

the socket-to-defect environments

may be exhibited. The degree to

which one or the other environment

is manifested and dominates the lo-

cal topography serves as one of the

determining factors for choosing the

optimal treatment approach. An od-

ditional factor that influences treat-

ment decisions is the quantity of the

remaining labial plate of bone. This

is especially important in the anterior

segment because of the more de-

manding esthetic requirements. We

suggest the following guidelines for

classifying and treating extraction site

deformities.

Type 7 extraction site to 5-mm offset is best, because it

allows an optimal emergence

profile of the restoration from the

fixture.

4. The labial plate of bone is ade-

quate, and recession on the tooth

to be extracted is manageable, or

where esthetics is not paramount

(ie, in a patient with a low smile-

line or in posterior quadrants).

T ype 1 extraction sites, such as the

ones exhibited about fractured roots,

are best suited for immediate implant

placement utilizing the principles of

GTR. The critical requirement of initial

stabilization is most readily achieva-

ble at these sites. In addition, al-

though the volume of the socket can

be large, the potential for regenera-

tion in that environment is also great

(Figs 3a to 3d).

The Type 1 site is an incipient defect

environment with a good regenera-

tive potential and an acceptable es-

thetic prognosis:

1 .The environment is dominated by

the four-wall socket or the incipi-

ent three-wall deshiscence-type

defect (5 mm or less in the api-

cocoronai direction). The osseous

crests lie in the coronal third of the

root to be extracted.

2. Adequate bone is available (ie, 4

to 6 mm) beyond the apex for

initial stabilization of an implant.

3. Osseous crestal topography is

harmonious, permitting an ac-

ceptable discrepancy between

the head of the fixture, in the ex-

traction socket, and the necks of

the adjacent teeth. Usually a 3-

The International Journal of Periodontics & Restorative Dentistry

317

The obvious advantages of im-

mediate implant placement are its

expediency and relative predictabili-

ty. Compared to the duration of tra-

ditional periodontal-prosthetic pro-

cedures, the length of treatment with

implant restorations is significantly in-

creased because of the additional

time involved in performing ad-

vanced regenerative techniques and

in the healing phase of osseointe-

gration. It is, therefore, fortunate that

many cases are amenable to treat-

ment with immediate implant place-

ment. In more severely compromised

sites, however, alternative adjunctive

techniques become necessary , es-

pecially where esthetic detailing or an

increased length of the fixture is re-

quired.

T ype 2 extraction site

A Type 2 site is a moderately com-

promised regenerative and esthetic

environment:

these valuable resources. Specifical-

ly, manipulation of these tissues

through tooth movement, in the more

compromised environment, offers the

potential for positively altering the

potential implant recipient site and,

therefore, for optimizing the treatment

and final result.

The Type 2 extraction environment

poses several functional and esthetic

limitations. The reduced regenerative

potential of the significant defect en-

vironment may force a more apical

and possibly less than ideal place-

ment of the implant (Fig 4). Anatomic

restrictions may require the use of

shorter fixtures. In addition, compro-

mises in the form of longer restora-

tions or uneven gingival margins may

prove esthetically unacceptable. In

view of these challenges, controlled

extrusive tooth movement is pre-

sented as an adjunctive treatment

approach for the Type 2 environ-

ment.

The ability of a tooth to affect its

environment orthodontically is con-

tained across the entire length of its

attachment. Therefore, it is recom-

mended that, when feasible or nec-

essary , the designated hopeless

tooth be extruded almost to extrac-

tion to achieve maximal benefits. The

authors suggest the term orthodontic

extraction for this process, because

its purpose is to extract the tooth with

all the augmentative benefits inherent

to the orthodontic extrusive process.

This approach, used alone, works

best for teeth with moderate soft and

hard tissue defects, because these

teeth usually still have a significant

amount of attachment remaining. The

aim of this technique is to manipulate

this remaining attachment orthodon-

tically to augment the gingival and

osseous tissues in a vertical direction.

as the ones characteristic of the Type

2 site. In these cases, successful

bone regeneration is limited by the

reduced regenerative potential of the

site and the increase in exposed im-

plant surface.

Therefore, to achieve greater suc-

cess in the Type 2 environment, ther-

apy that increases the regenerative

potential becomes vital. Preliminary

ridge augmentation would serve this

purpose. However, it requires an

added surgical procedure and is time

consuming. A relatively more expe-

dient approach is orthodontic modi-

fication of the defect; hopeless teeth

can be used to modify the Type 2

site.

For teeth designated as hopeless,

the usual treatment planning per-

spective for the fixture-assisted res-

toration currently suggests only two

possibilities. The first is to extract

hopeless teeth strategically as part of

inflammatory control and, when fea-

sible, to place implants immediately.

The second possibility is to retain the

hopeless teeth temporarily to help

stabilize a provisional restoration

while implant fixtures are osseointe-

grated.These hopeless teeth, however, af-

ford other unique advantages prior

to extraction that can enhance the

results of cosmetic and regenerative

procedures. Because hopeless teeth

are not necessarily useless teeth, the

most alluring advantage that these

teeth offer resides in their remaining

attachment apparatus, ie, periodon-

tal ligament, bone, and cementum. It

is ironic that so much effort is put into

regenerating these valuable tissues,

considering how quickly they are dis-

carded as part of "strategic extrac-tion. " By contrast, our approach to

treatment planning capitalizes on

1 .A moderate defect environment is

predominant, and it extends

through the middle third of the

root; this includes dehiscences of

greater than 5 mm.

2. The discrepancy between the os-

seous crests of the remaining

socket and the necks of adjacent

teeth is substantial.

3. Recession is significant and loss

of the labial plate of bone is mod-

erate. This is especially critical in

the anterior region of the mouth in

a patient with a high smileline.

While examples of successful os-

seous regeneration of three-wall de-

hiscences measuring 5 mm or less

have been reported in the implant

literature,38,39 no guidance is given for

treating more extensive defects, such

Volume 13 Number 4 1993

318

Fig 4 Present options for treatment of the Type 2 extradion site. All of them involve GTR utilizing a baITier membrane. (A) A Type 2extraction site, the defect environment extends into the middle third of the root and possibly involves a dehiscence of greater thanS mm. (B) The implant is placed so that the head of the fixture is positioned ideally in relation to the neck of the adiacent tooth (3 toS mm). This positioning, however, leaves a large segment of the fixture supraosseous and makes success less predictable. (C) Moreapical placement of the fixture into the more regenerative environment may create soft tissue compromises or an unesthetically longclinical crown. (D) To address the treatment concerns, preliminary ridge augmentation may become necessary.

In essence, by relocating the more

regenerative socket environment co-

ronally we are eliminating the less re-

generative defect environment and

turning a Type 2 site inta a Type 1

site (Fig 5). Also, where the campro-

mised teeth have flared labially, re-

traction can be performed simulta-

neausly during the extrusive pracess.

This will favorably realign the socket

environment palatally sa that the im-

plant can be placed at an angle that

will nat compromise the prosthetic

restaration (Fig 6).

The osseous leveling effect of or-

thodontic extraction at the Type 2 site

offers several benefits over the im-

mediate implant placement proce-

dure. The most important benefit is

the creation of a greater volume of

available bone to engage the im-

plant at the time of placement. Re-

cent studies of immediate implant

placement into extraction sockets or

areas that involve a deshiscence

have revealed that some specimens

exhibit an interposing fibrous seam

befween the initially exposed implant

surface and the newly augmented

bone.4°.41 These results are prelimi-

nary and may eventually be attrib-

utable to the short observation peri-

od. However, we believe that ac-

quisition of a natural and circumfer-

entially more intimate contact be-

tween the implant and the adjacent

bone at the leveled site may result in

greater initial stabilization of the fixture

and possibly earlier osseointegration

over a larger surface area (Fig 7).

The International Journal of Periodonncs & Restoranve Dentis""

319

Fig 5 (A) A hopeless tooth with a Type 2 classification. (B) A pulpectomy is performed, periodontal inflammatory control is instituted,and extrusi,:,e mechanics is employed. (C) !he result transforms a Type 2 site into a Type 1 site: (.D) Greater predictable success. withimmediate Implant placement may be achieved because more surface area of the fixture IS In IntImate contact WIth the suIToundlngbone than would have been the case in the original situation (A)

Further, the increase in the gingival

dimension that is achieved embodies

significant esthetic and technical ben-

efits. Beside providing the consider-

able esthetic advantage of leveled

gingival margins, this approach al-,

lows the regeneration of the gingival

papilla (Fig 8). The lip of bone that

follows the erupting tooth can create

and maintain a papilla at the final

restoration. The increased width of

the attached gingiva, in addition,

minimizes the need to lift the tissue to

cover the extraction site, and thereby

reduces the possibilily that the vesti-

bule will be shallow. In many in-

stances, these soft tissue benefits will

reduce or eliminate the need for mu-

cogingival procedures later.

Volume 13 Number 4. 1993

320

Fig 6a A 58-year-old patient with hy-permobile and flared anterior teeth pre-sented for treatment.

Fig 6c A provisional restoration wasplaced from the right canine to the leftfirst molar. The crowns of the canineswere removed and pulpectomies wereperformed. The roots were debrided tothe base of the pocket with a diomondused at high speed. Extrusive and retrac-tion mechanics were employed within theprovisional restoration.

Fig 6b A panoramic radiograph reveals wide circumferential defects around the maxil-lary canines. The roots of the canines extend to the floor of the nasal cavity, and theamount of bone is not adequate to engage and stabilize an implant.

The International Journal of Periodontics & Restorative Dentistrv

321

Fig 6d Tissue at completion of the orthodontic phase. Figs 6e to 6h Periapical radiographs ofthe right and left sides before and afterextrusion.

Figure 6{ Figure 6hFigure 6g

Volume 13, Number 4, 1993

322

Figs 6i to 6n Reformatted computerizedtomographic scans taken before andafter orthodontic extrusion. Note the verli-cal increase in engageable bone and thequalify of the transformed recipient sitesafter extrusion. In Figs 6m and 6n, the ef-fect on the ridge of simultaneous palatalextraction of the left canine is evident.(Courtesy of Biometrix Tech.)

Figure 6i

Figure 6i Figure 6k

The International journal of Periodontics & Restorative Dentistry

324

Fig 60 Stage 1 surgery. Note the com-plete elimination of the defect environ-ment.

Fig 6p The left lateral incisor and caninehave been extracted and implants havebeen placed. A membrane will beplaced for GTR on the two exposedthreads on the labial aspect of the ca-nine area and to augment the thin labialplate of bone.

Fig 6q Two 13-mm fixtures and three 10-mm fixtures have been placed in the left andright sides, respectively. Periapical radiographs at 3 months.

The International Journal of Periodontics & Restorofive Dentistry

325

Fig 7a Maxillary right canine with 9-mmprobing depth inter proximally and 6-mmprobing depths facially and palatally. In-cluding the 5 mm of recession and thebiologic width, the labial crest can be as-sumed to be approximately 13 mm api-cal to the cementoenamel iunction; there-fore, this is a Type 2 site.

Fig 7b Use of an implant was plannedto assist stabilization of a maxillary resto-ration. The canine was extruded and re-traded to modify the recipient site.

Fig 7c Postextrusion radiographs of the defect environment during stabilization, (left toright) at 0, 2, and 6 weeks.

Fig 7d New coronal position of the(arrow) labial crest of bone.

Fig 7e Implant placed completely in asocket environment.

Volume 13, Number 4, 1993

326

Fig 7g Radiograph at 3 months.Fig 7f Tissue during osseointegrotion phase. Note harmony of mucogingival margin.

Fig 80 A 61-year-old patient presented for treatment with a failing maxillary restorationassociated with recession. There is inadequate bone to place implants in the maxillaryright quadrant.

Figs Bb to Be Moxillary right canineprior to extrusion.

The Internationol Journal of Periodontics & Restorotive Dentistry

327

Figure Bc Figure Bd Figure Be

Fig Sf The vertical dimension of thebone at the recipient site is increased

postextrusion.

Fig Bg The postextrusion soft tissuechanges are dramatic, as revealed by theformation of (arrow) new papilla.

Fig Bh Compare soft tissue to thatshown in Fig Be.

Volume 13, Number 4, 1993

328

mediate implants or sufficient remain-

ing attachment for effective extrusion,

the principles of GTR should be used

to achieve preliminary ridge augmen-

tation.

Type 3 extraction site

A Type 3 site is a severely compro-

mised environment in which imme-

diate implant placement is not an

option:

1. Vertical and buccolingual dimen-

sions of bone are inadequate for

placement and stabilization of im-

mediate implants.

2. Recession is present and loss of

the labial plate of bone is severe.

3. Severe circumferential and angu-

lar defects are present.

In experiments with GTR, Gottlow

and Nyman43 found that the volume

and shape of the tissue generated

under the membrane seemed to be

determined by the configuration ofthe " artificial space. " Seibert and

Nyman20 recently presented a pilot

study of localized ridge augmenta-

tion in dogs. Their findings suggested

that some collapse occurred where

the membrane was not supported.

Additionally, in the areas in which the

membrane did not retain its shape,

less regeneration was observed.

Therefore, space maintenance under

the membrane is a critical compo-

nent, especially when large defects

are t~eated.

The eruptive phase in this tech-

nique usually requires 4 to 6 weeks.

It is followed by 6 weeks of stabili-

zation before the tooth is removed

and the implant is placed. While this

approach adds to.the length of treat-

ment, it is significantly more expedient

than GTR ridge-augmenting tech-

niques, which require 6 to 9 months

before implant placement. Use of this

technique to address the moderate

defect environment allows more pre-

dictable placement of longer im-

plants because the coronal reloca-

tion of the osseous crest. The tech-

nique also results in a more esthetic

final restoration by creating a leveled

implant receptor site in harmony with

the adjacent natural teeth.

One contraindication for forcibly

erupting teeth is the presence of

chronic, uncontrollable inflammatory

lesions, including combined endo-

dontic-periodontic lesions and frac-

tured roots. It is suspected that the

fiber apparatus of such teeth is ex-

tremely compromised. Inability to

control inflammation and acute in-

fection may also adversely affect

healing and overall response to

treatment.

Even if the roots can be main-

tained, however, forced eruption only

relocates existing attachment. It does

not create new attachment. The abil-

ity of compromised teeth to influence

their adjacent tissues is limited by the

quantity of the remaining attachment

and the integrity of the fiber appa-

ratus. Poison et al42 studied tooth

movement into infrabony defects and

found that only alveolar bone that

was attached to the root via peri-

odontal fibers accompanied the

tooth in its movement. Hence, when

hopeless teeth lack adequate sur-

rounding bone for stabilization of im-

Treatment of the Type 3 environ-

ment begins with a thorough de-

bridement of the extraction site. In our

protocol, this is followed by the

placement of a mixture of decalcified

freeze-dried bone allograft (DFDBA)

and tetracycline, covered by GORE-

TEX Augmentation Material barrier

membrane (Gore). The main pur-

pose of the DFDBA is to serve as

scaffolding for space maintenance,

especially where the natural anatomy

of the defect environment is incap-

able of supporting the shape of the

membrane. We have, on occasion,

submerged roots of hopeless teeth

as an alternative method of adding

support to the tenting of the mem-

brane (Fig 9). Buser et al22 presented

reports of cases in which minicortical

screws were applied, in certain in-

stances, for the same purpose.

Another advantage of utilizing

DFDBA is for stimulating bone for-

mation through the osteogenic prop-

erties of the bone-morphogenic pro-

tein inherent in the graft medium.44.45

The tetracycline, on the other hand,

is used to enhance the osteogenic

potential of the allograft46 and to

provide local antimicrobial cover-

age.47The above-described treatment

option may be viewed as a two-step

approach,9,48 similar to methods used

to address long-standing ridge de-

fects. The first step is the augmen-

tation procedure, which usually re-

quires 6 to 9 months for full miner-

alization to occur. The second step is

the actual implant placement, which

may itself require another augmen-

tation procedure if the initial attempt

is not sufficient.

The Internotionol Journol of Periodontics & Restorotive Dentistry

329

Fig 9a Radiographs reveal hopelessteeth with severe periodontal breakdown.It is likely that no bone is available for

implant placement postextraction.

Fig 96 At the time of extraction, a deep,concavity is found in the right anterior re-

gion

Fig 9c The maxillary right first premolarhas been extracted. The crown has beenremoved from the canine, but the roothas been retained to tent the membrane.InteImalTOW penetration has also beenperfolmed.

Fig 9d The membrane became exposedat 3 months and was removed. Note thecomplete regeneration of the ridge. Thetissue demonstrates a hard, cartilaginousconsistency. Implants will be placed inthe future.

Volume 13, Number 4, 1993

330

Fig lOa The maxillary right first premolarand canine demonstrate probing depthsof 6 to 9 mm. In addition, the premolarhas a Class III furcation involvement. Theoriginal treatment plan included extractionof the teeth and replacement with im-

plants.

Fig 1 Ob Initial extrusion. The palatal rootof the first premolar was subsequentlyamputated and the buccal root was ex-truded.

Fig lOc Postextrusion. The teeth wereprovisionally restored to stabilize the re-sult.

Fig IOd Two months postextrusion, thefirst premolar and canine exhibited mini-mal probing depths and were so stablethat they were given permanent restora-lions. No surgery was ever performed.(Courtesy of Bruce Goldmon, DMD.)

The International Journal of Periodontics & Restorative Dentistry

331

Discussion SummaryReferences

There can be several successful ap-

proaches to a problem. The devel-

opment of a more rigid membrane,

for example, may offer a better op-

tion than the use of screws, retained

roots, or grafts for space mainte-

nance. In addition, the development

and availability of bone growth fac-

tors may enhance the regenerative

potential around more compromised

sites. The categories and treatments

that have been outlined are intended

as a general guide to viewing the

potential extraction site. They high-

light the complexities and choices

that presently abound in treatment

planning for fixture-assisted dental

restorations, even for a specific ap-

plication, such as the management

of hopeless teeth and their compro-

mised environment. At the same time,

degrees of success vary with every

modality of treatment. The techniques

presented have offered the spectrum

of successes. Probably the most sat-

isfying experience is when the tech-

nique works so well that teeth initially

designated as hopeless can be re-

tained (Fig la).

When compromised teeth are to be

extracted, a well-organized and ver-

satile treatment approach is neces-

sary to maintain or achieve adequate

dimensions at these sites for predict-

able implant placement. Hence, cri-

teria and guidelines for the manage-

ment of various extraction defect en-

vironments were outlined. Within that

framework, a new perspective was

presented that allows the optimal

management and utilization of avail-

able assets, ie, hopeless teeth and

their attachment apparatus, to aug-

ment both the soft and hard tissue

profiles of potential implant sites.

Esthetic enhancement of the po-

tential peri-implant gingival margin

through orthodontic extrusion was

demonstrated. In addition, the os-

seous profile in the vertical dimension

was enhanced. Combined with GTR

procedures, these techniques can re-

sult in more predictable placement of

implants in sites that may initially

have been inadequate.

1. Bronemark P-I, et al. Osseointegratedimplants in the treatment of the ed-entulous jaw. Experience from a 10-year period. Scand J Plast ReconstrSurg 1977;11 (suppl16).1-132.

2. Adell R, Lekholm U, Rockier B, Brone-mark P-I. A 15-year study of osseointegrated implants in the treatment ofthe edentulous jaw. Int J Oral Surg1981 ;6.387-416.

3. Hansson HA, Albrektsson T, Brone-mark P-I. Structural aspects of the in-terface between tissue ond titanium im-plants. J Prosthet Dent 1983;50.108-113.

4. Lindquist L, Carlsson G, Glantz PO.Rehabilitation of the edentulous mon-dible with tissue integrated fixed pros-thesis: A six-year longitudinal study.Quintessence Int. 1987; 18.89-96.

5. Ohrnell LO, Hirsch JM, Ericsson I, Bro-nemark P-I. Single tooth rehabilitationusing osseointegration. A modified sur-gical and prosthetic approach. Quint-essence I nt 1988; 19:871-876.

6. Schulman LB. Surgical considerationsin implant dentistry. J Dent Educ1988;52: 712-720.

7. Barzilay I, Graser GN, Iranpour B, Na-tiella JR. Immediate implantation of apure titanium implant into an extractionsocket. Int J Oral Maxillofac Implants1991;6:277-284.

8. Bahat 0, Deeb C, Golden T, Komar-nyckyj 0. Preservation of ridges utilizinghydroxyapatite. Int J Periodont RestDent 1987;7(6).35-41.

9. Lundgren D, Nyman S. Bone regen-eration in two stages for retention ofdental implants. Clin Orol Impl Res1991 ;2:203-207.

Acknowledgments

We would like to thank Drs Masakazu Nish-ibori, Fernando Presser, and Jae Hwang,Graduate Students in Periodontal-Prosthe-sis at the University of Pennsylvania. Theirclinical support and contributions helped toenrich this paper.

We are also very grateful to Daniel Free-man and Biometrix Technologies, Inc, fortheir technical help in reformatting and cre-ating graphics for the CT -scans presented.

Volume 13, Number 4, 1993

332

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Volume '3 Number 4. 1993