When to Save or Extract a Tooth in the Esthetic Zone- A Commentary

136 Compendium April 2008—Volume 29, Number 3

The goal of restorative dentistry is to reinstate good form

and function to the dentition with excellent esthetics and

health. Fundamental to developing a dental treatment plan,

a prognosis must be assigned to each tooth. With regard to

problematic teeth, questions should be resolved concerning

the need for their therapy or replacement. For instance, can

a tooth be effectively restored? Will endodontic treatment be

successful? Is periodontal therapy a reasonable option? After

therapy will a treated tooth be a suitable abutment? What

effect will extraction of a tooth have on the final treatment

plan? Articles have addressed some of these issues; however

When to Save or Extract a Tooth in the Esthetic Zone: A Commentary

Gary Greenstein, DDS, MS;1 John Cavallaro, DDS;2 and Dennis Tarnow, DDS3

Learning Objectives:

After reading this article, the reader should be able to:

■ describe the consequences of surgical procedures in

the maxillary anterior region.

■ discuss factors that need to be considered when treat-

ment planning in the esthetic zone.

■ list alternate treatment plans for the premaxilla zone

that can be used to maintain esthetics.

1Department of Periodontology and Implant Dentistry, New York University College of Dentistry, New York, New York;

Private Practice, Freehold, New Jersey2Associate Professor, Department of Periodontology and Implant Dentistry, New York University College of Dentistry, New York,

New York; Private Practice, Brooklyn, New York3Professor and Chairman, Department of Periodontology and Implant Dentistry, New York University College of Dentistry,

New York, New York; Private Practice, New York, New York

Continuing Education 1

Abstract: BACKGROUND: In the esthetic zone, difficult decisions must be made regarding extraction or retention of com-

promised teeth. Numerous factors need to be considered to arrive at a proper treatment plan, which may differ from a plan

devised for the posterior region of the mouth. TYPES OF REVIEWED STUDIES: Studies were selected that provided back-

ground information for clinical decision-making concerning whether a compromised tooth should be retained or removed.

RESULTS: In the esthetic zone, before resective surgical procedures are used to resolve periodontitis, consideration should be

given to the esthetic outcome. If endodontic therapy is required, additional issues need to be reviewed before initiating

treatment, including restorability of the tooth, presence of a large periapical area, use of the tooth as an abutment, etc.

Furthermore, before initiating periodontal or endodontic treatment, the patient’s susceptibility to additional periodontal

disease progression and caries should be evaluated. CLINICAL IMPLICATIONS: In the esthetic zone, deciding whether to

treat or remove a compromised tooth requires careful deliberation. The possibility that additional bone loss can compro-

mise a future implant site needs to be considered before providing periodontal therapy. This is particularly true if recession

will be induced. Endodontic therapy is effective; however if crown lengthening is required because of subgingival caries or

tooth fracture, thought needs to be given to removal of the tooth before altering the gingival topography. Numerous other

factors need to be considered when deciding whether to save or extract a tooth in the esthetic zone: restorability, disease

susceptibility, papillary and gingival considerations, tooth esthetics, etc. In conclusion, the decision to extract or maintain

teeth must include deliberation with regard to benefits vs risks of retaining compromised teeth. The judgment to remove a

tooth may be based on one critical issue or it may rely on collective risks related to a few factors.

Greenstein et al.

www.compendiumlive.com Compendium 137

none of them have specifically discussed these issues as they

pertain to teeth in the esthetic zone.1-3 Therefore, numerous

factors were evaluated to determine if they can be used to

arrive at a correct judgment regarding whether to retain or

extract compromised teeth when esthetics is an additional cri-

terion for success. These factors are discussed with regard to

four major subjects: periodontal status and gingival contours,

restorability, endodontic considerations, and resistance to dis-

ease (periodontitis and caries). Ultimately, when developing a

treatment plan, the decision to retain or extract teeth is based

on the risks vs benefits of alternate treatments. Sometimes one

factor can be the critical determinant dictating that a tooth

should be removed; other times, decisions to remove a tooth

are based on cumulative risks associated with several factors.

CASE EVALUATIONTo develop an optimal treatment plan the clinician must

envision the completed dental rehabilitation. In this regard,

factors that contribute to achieving a cosmetic result in the

esthetic zone include: smile line, midline, tissue level, height,

width, and position of teeth. The smile line is considered

high if there is exposure of the teeth and gingiva.4 It is judged

average when 75% to 100% of the maxillary incisors are dis-

played and low if < 75% of the teeth are seen.4 It is more

difficult to achieve an optimal esthetic result when there is a

high smile line because discrepancies in tooth and gingival

or papillary height are visible.

The average length of the maxillary central incisors and

canines for men is 10 mm (range 7.7 mm to 11.9 mm) and

the corresponding teeth for women are approximately 1 mm

shorter.5 Lateral incisors are approximately 1.4 mm shorter

than central incisors for both genders.5 The gingival crest of

the central incisors and canines is approximately 1 mm above

the crest of the lateral incisors; the crest of the canines may be

a little higher.6 The peak of the gingival parabolic curve on

the central incisors and canines is slightly distal to the long

axis of the teeth, whereas it is at the midline of the long axis

of the lateral incisors.6,7 This subtle shift of the gingiva en-

hances a pleasing smile line. At the incisal edge, the lateral

incisor is approximately 1 mm shorter than the central inci-

sor.7 The position of the anterior teeth’s incisal edges are im-

portant for esthetics and phonetics. The width of the lateral

incisor is usually two-thirds the width of the central incisor,

which provides an attractive proportion to anterior teeth.6,7

In a healthy dentition with no bone or clinical attach-

ment loss, the underlying alveolar crest follows the scallop

of the cementoenamel junction (CEJ) and is around 2 mm

apical to the CEJ. The maxillary anterior interdental crests

are around 3 mm coronal to the facial bone height (range

2.1 mm to 4 mm).8 On average the free gingival margin is

approximately 3 mm coronal to the crest of the bone (bio-

logic width plus sulcus depth).9 Interproximally, interdental

papilla between the central incisors are 4.5 mm coronal to

the osseous crest and 4.5 mm to 5 mm coronal to the facial

gingiva.9 The additional height of the papilla (1.5 mm) is

caused by hypertrophy of the interdental tissue and includes

the col area when a contact point is present. The absence of

osseous support and proper gingival contours need to be con-

sidered when developing a treatment plan in the esthetic

zone. Compromised teeth may be deficient in diverse ways;

therefore, treatment planning in the premaxilla should con-

sider esthetics, form and function, and biology. In particular,

retention or removal of compromised teeth must be consid-

ered with regard to the esthetics of the final case.

PERIODONTAL CONSIDERATIONSPrevalence and Incidence of Periodontal Disease ProgressionAccording to the National Health and Nutritional Exami-

nation Survey (NHANES III), among dentate individuals

who are 30 years of age or older, approximately 30% of adults

develop periodontitis of varying degrees.10 The patterns of

bone destruction may be linear, episodic, at the same loca-

tion, or random events.11 Different models of disease pro-

gression can occur at various sites within the same mouth or

at a particular location at different times. Currently, it is not

possible to accurately forecast which sites will manifest dis-

ease progression. Therefore, if patients continue to deterio-

rate, despite periodontal therapy, it is prudent to remove com-

promised teeth before additional supporting bone is resorbed

and the residual osseous support decreases to < 10 mm. In a

systematic review, Goodacre et al12 found that ≥ 10 mm of

bone is desirable when placing an implant because integrat-

ed implants ≥ 10 mm in length demonstrated better survival

Sometimes one factor can be the critical determinant dictating that a tooth should be removed; other

times, decisions to remove a tooth are based on cumulative risks associated with several factors.

rates than shorter implants. Furthermore, bony support is

critical for the esthetic form of the gingival tissues.

Size of Periodontal DefectsIt is usually desirable to maintain shallow rather than deep

probing depths around teeth for multiple reasons: shallow

depths facilitate supragingival hygiene, which impacts the

subgingival microflora; there is less bleeding on probing; at

shallower sites it is easier to instrument root surfaces; there is

less predisposition for disease progression; and shallow depths

are better forecasters of periodontal stability.13 Pertinently,

periodontal surgery is often done to reduce or eliminate deep

probing depths.14 However, a usual consequence of peri-

odontal surgery is recession of the gingiva and interdental

papillae, which may create undesirable “black triangles” be-

tween teeth. Therefore, resective procedures that create an

unesthetic gingival topography are contraindicated on teeth

that have a questionable prognosis in the esthetic zone. In

addition, surgical procedures may result in large interdental

embrasures, which are plaque retentive and may cause in-

creased thermal sensitivity (Figure 1).

The judgment call by the clinician whether to extract or

retain a tooth needs to include consideration of the smile

line, severity of the periodontal condition, expected reces-

sion induced by pocket elimination procedures, the need for

endodontic intervention with or without post/cores, and the

emotional and esthetic concerns of the patient. Ultimately,

in the esthetic zone, it is prudent to remove periodontally

questionable teeth and replace them with implants if this

will assist in maintaining the height of the gingiva and bone.

A consequence of maintaining the gingival height where bone

loss has occurred is the need to tolerate increased probing

depths around implants when they are placed, or the accept-

ance of the commitment to rebuild osseous support before

implants are placed (site development). Atassi15 found that

it is preferable to have shallow sulci around an implant, but

that deep probing depths do not necessarily reflect peri-

implantitis unless there is disease progression.

Preservation of BoneSix months after an extraction of maxillary anterior teeth,

there is loss of bone ridge width (x = 4.56 mm) and height

(x = 1.5 mm) if socket preservation techniques are not used

(eg, bioabsorbable barrier).16 Most of the osseous resorp-

tion occurs during the first 3 months after tooth removal.17

This expected bone loss must be considered in light of the

deterioration that already occurred because of periodontitis.

Even immediate placement of implants into extraction sites

does not prevent initial bone resorption from occurring.18

Subsequently, integrated implants provide stimulation to

the alveolar bone and retard osseous resorption,19 whereas

an edentulous ridge without implants continues to resorb if

a removable prosthesis rests on the ridge.20,21

RESTORATIVE CONSIDERATIONSBiologic WidthThe term biologic width refers to the junctional epithelium

and connective tissue attachment coronal to the bone; it

does not include gingival sulcus depth. The biologic width

consists of approximately 1 mm of junctional epithelium

and 1 mm of connective tissue,22 but it can range from 1 mm

to 4 mm.23 This region must be respected when restorations

are fabricated; otherwise there may be chronic gingival in-

flammation, pain, and unpredictable bone loss. Accordingly,

when crown-lengthening procedures are performed, the bone

needs to be placed 2 mm to 3 mm apical to the margin of

the fixed prosthesis.24 Therefore, problematic teeth in the

esthetic zone that require a crown-lengthening procedure



Figure 1 Periodontal surgical procedures on compromised

teeth to eliminate deep probing depths usually result in

recession interdentally and facially.

If patients continue to deteriorate, despite periodontal therapy, it is prudent to remove compromised

teeth before additional supporting bone is resorbed and the residual osseous support decreases.

Greenstein et al.


(eg, caries under a crown) should be evaluated for extraction,

because these measures may result in an unesthetic appear-

ance. Furthermore, increasing crown height usually involves

osseous recontouring of the proximal surfaces of adjacent

teeth, thus more than one tooth is affected.

Remaining Tooth StructurePrediction criteria for successfully restoring a tooth that un-

derwent endodontic therapy include 5 mm of suprabony

structure: 2 mm for the biologic width, 2 mm for the ferrule,

and 1 mm sulcus depth.25 A ferrule is the cervical portion of

a restoration that extends 1 mm to 2 mm onto sound tooth

structure to prevent fractures.26 Finally, after the post is pre-

pared, there should be enough root length remaining to per-

mit a 4-mm apical seal to impede bacterial penetration.27

Surgical crown lengthening of a compromised tooth

that has a poor crown-to-root ratio should be avoided.1

Furthermore, even though some teeth can be retained, stra-

tegic extractions of compromised teeth need to be consid-

ered to facilitate an optimal restorative result.1

CariesCaries is an infectious disease and affects many adults over

50 years of age.28 Factors that influence the incidence of ca-

ries include environment, oral hygiene, genetics, diet, sali-

vary flow, level of Streptococcus mutans, etc.29 In addition,

among patients with recession, cementum and dentin are

more susceptible to caries than enamel because of their lower

mineral content.30 Caries is a major concern among patients

undergoing prosthetic rehabilitations, as it is the main rea-

son for loss of fixed partial restorations.31

In the esthetic zone, if a patient has caries under a fixed

prosthesis, crown lengthening should be avoided because it

will induce recession and usually result in asymmetric gingival

margins (Figure 2). Individuals with a high caries index are

prone to additional caries;32,33 therefore, for these patients, it

is prudent to avoid crown lengthening and advisable to re-

place the tooth with dental implants, which cannot decay.

An alternate therapy to crown lengthening to expose sub-

gingival caries is extrusion of a tooth, which can reduce es-

thetic issues. Orthodontic extrusion for approximately 8 to

12 weeks followed by 4 to 6 weeks for stabilization also can

align disharmonious gingival margins and improve the os-

seous topography at a compromised site.34 However, af-

ter forced eruption, some interproximal crown lengthening

may still be needed. In this regard, the length of therapy,

additional costs to retain the tooth, and the willingness of

the patient to wear braces for several months need to be con-

sidered. Furthermore, the new crown will have a narrower

cervical third because a segment of the root will now be posi-

tioned where the crown margin was previously located. In

particular, this may produce an unesthetic result if only one

central incisor is extruded because asymmetry is created be-

tween the necks of the central incisors.

Teeth Adjacent to Edentulous AreaThe decision to extract or retain teeth affects adjacent teeth,

especially if they are to function as abutments for a fixed or re-

movable partial denture. Pertinently, Aquilino et al35 reported

that patients wearing removable partial dentures over a 10-year

period lost 44% of abutment teeth, and Wagner et al36 noted

that only 42% of removable partial dentures remained in serv-

ice for 8 years. Therefore, treatment planning must include

consideration of the functionality of adjacent teeth. At present,

there are no studies that indicate loss of bordering teeth occurs

when implants are inserted. In contrast, a large edentulous

Figure 2 Crown lengthening should be avoided if there is

caries under a crown in the esthetic zone because it will

result in recession and an unesthetic appearance.



area may require the span of a fixed partial denture to be ex-

tended to incorporate teeth that require endodontic or peri-

odontal treatment, thereby possibly compromising the long-

term stability of the prosthesis.

It is also important to evaluate the functional load which

will impact on restored teeth. Several studies reported that

fixed partial dentures, which used endodontically treated

teeth as abutments, failed more often than crowns prepared

on vital teeth.37-39 In general, single endodontically treated

teeth should be used cautiously as abutments to support dis-

tal extension partials or cantilevers because they are subject

to additional occlusal loading.25 However, there are excep-

tions to this concept, which will depend on the clinician’s

judgment related to the survivability of the retained tooth.

Numerous investigations have addressed success rates of

fixed partial dentures (FPDs) and implant restorations. Wal-

ton et al40 reported that the long-term survival rate of FPDs

was 87% at 10 years and 69% after 15 years. A recent meta-

analysis concerned with the success of FPDs found that af-

ter 10 years the success rate (retained without problems) was

71.1% and the survival rate (maintained) was 89.1%.41 In con-

trast, the following survival rates were reported with single-

unit implant restorations: 97.5% after 6 to 7 years;42 97.4%

after 10 years;43 and 96.5% over 11 years.44

ENDODONTIC CONSIDERATIONSSuccess of Endodontic TherapiesConventional endodontic therapy has a high success rate.45,46

However, numerous issues need to be considered before endo-

dontic therapy with a post and crown on a tooth in the esthet-

ic zone. The 2003/2004 Toronto study found the endodontic

success rate on vital teeth to be 92%, on nonvital teeth with-

out a periapical area to be 89%, and on nonvital teeth with a

periapical area to be 74%.47 For endodontic retreatment, the

study found the success rate for teeth without a periapical area

to be 95% and, when there is a periapical area, 66%.48 It is

also necessary to differentiate between success (no periapical

area) and survival (asymptomatic with periapical radiolucency

present) with regard to retained endodontically treated teeth.

Survival rates indicate that 95% of teeth that underwent en-

dodontic therapy are functional.45,46

With respect to apical surgeries, apicoectomies have a suc-

cess rate of 74% and a survival rate of 91%.49 Wang et al49

noted that when there was a large periapical radiolucency pres-

ent (> 5 mm) on a nonvital tooth, 65% of the sites healed,

whereas if the lesions were small (< 5 mm), 86% did not man-

ifest any periapical radiolucencies (Figure 3). A recent system-

atic review reported that endodontic surgery had a weighted

average of 64% success rate and that resurgery was successful

36% of the time.50 Unfortunately, apicoectomies do not always

avoid the need for dental implants. Furthermore, buccal fenes-

trations created to gain access to the periapical area may not heal

with an intact buccal plate of bone. Therefore, these procedures

may compromise an implant site and precipitate the need for

additional bone grafting when an implant is needed.

Other Endodontic ConcernsBefore any teeth are crowned, Whitworth et al51 advised

that the teeth be assessed to determine if endodontic therapy

is needed. This evaluation consists of a history of patient dis-

comfort, a clinical examination (eg, fistulas, color, percus-

sion, palpation), special tests (thermal or electrical), and ra-

diographs. Determination of the need for endodontic therapy

may impact the decision to retain or remove a tooth.

When considering endodontic therapy or apical surgery,

a number of other criteria suggest that a tooth should be

Figure 3 Teeth with periapical lesions > 5 mm should be

considered for extraction in the esthetic zone.

Greenstein et al.


extracted and replaced with a dental implant: if there is abnor-

mal root anatomy precluding successful endodontic obtura-

tion; when the root is short or thin and a post will predispose

the tooth to post loosening or root fracture; and when there is

a misaligned post that will weaken the root structure.

The etiology of internal root resorption is unknown.52 It is

considered a benign proliferate fibro-osseous disorder, and the

result of endodontic therapy and filling these lesion sites is not

predictable. Therefore, these teeth should be considered for ex-

traction if this condition is detected in the esthetic zone to avoid

compromising an implant site if endodontic therapy fails.

Pulp Mortality Among Crowned TeethIndividual teeth that require endodontic therapy or that will

be used as abutments for a fixed prosthesis call for crown

preparation. In this regard, studies disagree on the number

of teeth that will develop endodontic problems after crown-

ing. For example, a retrospective study found a percent range

of 0% to 2.19%,53 but when Valderhaug et al54 studied 291

endodontically treated teeth over 25 years, they found the

percentage to be as high as 10%. Furthermore, other studies

have indicated that during a 3 to 30 year period, 13.3% of

teeth restored with crowns became nonvital,55 and 20% of

vital teeth prepared as overdenture abutments developed peri-

apical lesions within 2.5 to 3 years.56 Among patients with

advanced periodontal disease, it has been found that 9% of

crowned teeth vs 2% of uncrowned teeth become nonvital.57

Thus, it appears that a small percentage of teeth become non-

vital after crowning, and this percentage may increase with

time. Another factor that could contribute to teeth becoming

nonvital is the preparation of teeth beyond what is usually done

to correct tooth position: for example, if multiple teeth had to

be made parallel to create a line of draw for a fixed prosthesis.

Previously Treated Root Canal TeethEndodontically treated teeth left uncrowned because of de-

fective or lost restorations should be considered unreliable,

because saliva and microorganisms migrate alongside ex-

posed root fillings.2,58 Researchers observed that, in vitro,

dye penetration reached 85% of the root length in 3 days.59

Therefore, Whitmore et al51 suggested that if a tooth were

exposed more than 1 month, the filling should be revised.51

If this is not possible, then the tooth should be considered

for removal, because it is at risk for failure.

The main function of endodontic posts is to retain the

core; however, these posts offer no reinforcement for the

tooth. Furthermore, dentin removal to facilitate post inser-

tion may weaken the tooth and create stress concentration at

its terminus.51 Therefore, whenever possible, posts should be

avoided. The incidence of problems associated with posts can

vary. In 1970, Roberts60 reported failure rates as high as 22%

over a 5-year period.

It can be concluded that routine endodontic therapy is

very successful, and survival rates for both endodontically

treated teeth and dental implants are high. Therefore, it isn’t

appropriate to conclude that one therapy is superior to the

other based solely on success rates.61 The other factors out-

lined need to be considered when deciding if a tooth should

be endodontically treated or replaced with a dental implant. If

there are multiple issues associated with endodontic therapy

that place the final restoration at risk, it may be prudent to

remove the tooth and avoid potential complications.

Figure 4 The average height of a papilla between 2 implants

is 3.4 mm. Note the short papilla between implant-supported

crowns on teeth Nos. 9 and 10.

Figure 5 Implants at sites Nos. 8 and 9 with a long contact

area between them.

Resistance to DiseaseThere is no accurate method to predict which site will expe-

rience caries in an individual. However, several authors con-

firmed that past caries experience was the most significant

predictor for future caries development.32,33 Thus, in indivi-

duals who have a high caries index or advanced periodontitis,

consideration needs to be given to using dental implants if a

prosthesis is being treatment planned. At present, the pre-

ponderance of data indicate that implants can be successfully

placed in patients who have lost teeth because of periodon-

titis. Recently, a systematic review concluded there was no

increased risk of losing implants among patients who lost

teeth because of progressive periodontitis, over individuals

who never had periodontal disease.62 However, the patients

who lost teeth because of progressive peridontitis did have a

higher incidence of peri-implantitis. Baelum and Ellegaard63

also reported that implants inserted in individuals with

a history of periodontitis had a 5-year survival rate com-

pared with implants placed in nondiseased patients. In this

regard, additional studies are needed to determine which

surface textures affect the ability of the implant to resist

peri-implantitis.

WHEN TO SAVE TEETHPsychological Impact of Losing or Retaining TeethIn general, endodontic and implant procedures cause mini-

mal postoperative discomfort and a low incidence of compli-

cations. Nevertheless, patients’ past experiences with either

treatment modality may influence their decisions and their

preferred course of action.64,65 Therefore, besides dental sta-

tus, time, and cost of therapy, patient preference needs to be

taken into account when establishing a treatment plan.66

Strategies need to be presented and decisions should be made

together to meet each patient’s best interest. Accordingly, if

an individual is very emotional when the word extraction is

used, consideration should be given to retaining teeth even if

a better esthetic result could be attained with extraction of

teeth and replacement with implants. However, the long-

term consequences of delaying an extraction(s) should be

explained to the patient and noted in the patient’s record.

Avoiding Two Adjacent ImplantsTo achieve an esthetic result, it is advantageous to have papil-

lary symmetry between contralateral sides of the dentition and

avoidance of short papillae between implants. Tarnow et al67



Figure 6A If teeth Nos. 6 and 7 are missing, one implant should

be placed at site No. 6 and site No. 7 should be cantilevered as

an ovate pontic. Note that the implant was placed with an

abutment at site No. 6.

Figure 6B Site No. 6 was restored with a crown and the pon-

tic at site No. 7 was cantilevered off the crown at site No. 6.

Figure 7 If teeth Nos. 7 through 10 need to be replaced,

implants should be inserted at locations Nos. 7 and 10. This

facilitates retention of normal sized papilla distal to site

Nos. 7 and 10 because the papillary height is determined

by the supracrestal fibers from the adjacent natural teeth.

demonstrated that implants should be placed at least 3 mm

apart to avoid bone loss, which can result in recession of pa-

pillae. In a later study, Tarnow and colleagues68 noted that the

average height of a papilla between two implants was 3.4 mm

and that > 50% of the papillae between implants were ≤ 3 mm

in height (Figure 4).68 Therefore, to attain the best esthetics, if

two adjacent implants are to be placed, modification of the

treatment plan may be necessary. If possible, consideration

should be given to saving one tooth to avoid short papillae.

Several scenarios may be encountered that require differ-

ent management approaches to achieve the best cosmetic re-

sults. In the maxilla, if teeth Nos. 8 and 9 are missing, they

can be replaced with implants, because the short papilla that

will form between them can be camouflaged by creating a

long contact area (Figure 5). Because the short papilla is in

the midline, it does not cause asymmetry.69 On the other

hand, if teeth Nos. 7 and 8 were lost, then one implant should

be placed at site No. 8 and an ovate pontic should be canti-

levered at site No. 7.69 If necessary, the gingiva can be aug-

mented before ovate pontic construction. Similarly if teeth

Nos. 6 and 7 were missing, then an implant could be placed

at site No. 6 and an ovate pontic placed at site No. 7 (Figure

6A and Figure 6B).69 If teeth Nos. 7 through 10 were extract-

ed, then implants should be placed at locations Nos. 7 and 10

(Figure 7).69 This will allow normal sized papillae to form dis-

tal to site Nos. 7 and 10 because the papillary height is deter-

mined by the supracrestal fibers from the adjacent natural

teeth.70,71 Then the shortened mesial papilla on site Nos. 7

and 10 will be symmetrical and can blend with the short pa-

pilla between site Nos. 8 and 9.

Thin BiotypeIf there is an option to retain a tooth that needs endodontic

therapy, and which also has a thin, healthy biotype, then

consideration should be given to retaining the tooth. This

may facilitate attaining a more esthetic result than extracting

the tooth because a thin biotype is prone to recession. In

this regard, Kan et al72 found that when thick and thin bio-

type periodontiums were compared with regard to papillary

height after single-tooth implant placement, the thin bio-

type demonstrated a shorter papilla by approximately 0.7 mm

and the facial tissue was approximately 0.4 mm shorter.

CONCLUSIONSThe decision to extract or retain a compromised tooth in

the esthetic zone requires guarded forward-thinking with

respect to the desired outcome. All therapies have potential

risks of complications and failures. Therefore, considerations

concerning esthetics, functionality, and personal preferences

expressed by the patient all impact the decision-making pro-

cess. Ultimately, practitioners need to base their definitive

therapy on: data from clinical trials, reasonable interpreta-

tion of that data concerning patient management, clinical

experience, patient preferences, and the medical and dental

histories of each patient.

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Greenstein et al.



Continuing Education Quiz 1

This article provides 1 hour of CE credit from Ascend Dental Media, now operated by AEGIS Communications. Record youranswers on the enclosed answer sheet or submit them on a separate sheet of paper. You may also phone your answers in to(888) 596-4605 or fax them to (703) 404-1801. Be sure to include your name, address, telephone number, and last 4 digits ofyour Social Security number.

Please see tester form on page 158.

1. The smile line is judged average when what percentage

of maxillary incisors are displayed?

a. 25% to 50%

b. 50% to 75%

c. 65 % to 85%

d. 75% to 100%

2. In the maxillary anterior region, interproximal papilla

between the central incisors are how many millimeters

coronal to the osseous crest?

a. 1.5 mm

b. 2 mm

c. 3 mm

d. 4.5 mm

3. Six months after extraction of maxillary anterior teeth,

if socket preservation techniques are not used, how

many millimeters of vertical bone height can be lost?

a. 0.5 mm

b. 1 mm

c. 1.5 mm

d. 4.5 mm

4. The term biologic width refers to:

a. junctional epithelium only.

b. junctional epithelium and connective tissue

attachment coronal to the bone.

c. junctional epithelium, connective tissue

attachment coronal to the bone, and

crevice depth.

d. junctional epithelium, connective tissue

attachment coronal to the bone, and

papilla height.

5. What is the main reason for loss of fixed partial

restorations?

a. porcelain fracture

b. endodontic failure

c. caries

d. periodontitis

6. Aquilino et al reported that patients wearing removable

partial dentures over a 10-year period lost what

percentage of abutment teeth?

a. 14%

b. 24%

c. 34%

d. 44%

7. A recent systematic review reported that endodontic

surgery has a weighted average success rate of:

a. 34%.

b. 44%.

c. 64%.

d. 86%.

8. Among patients with advanced periodontal disease,

it has been found that what percentage of crowned

teeth become nonvital?

a. 9%

b. 19%

c. 29%

d. 39%

9. What is the average height of a papilla between two

implants in the esthetic zone?

a. 2 mm

b. 3 mm

c. 3.4 mm

d. 4.4 mm

10. If teeth Nos. 6 and 7 were missing, what recommen-

dation was suggested to obtain the best esthetic result

with regard to papilla height?

a. Place an implant at site No. 6 and an ovate

pontic at site No. 7.

b. Place implants at sites Nos. 6 and 7.

c. Place an implant at site No. 7 and an ovate

pontic at site No. 6.

d. Fabricate a fixed partial denture, thus avoiding

implant placement.

Documents

When to Save or Extract a Tooth in the Esthetic Zone- A Commentary