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Sp oe 2555;35:131-40CU Dent J. 2012;35:131-40Original Article S ` S The use of a removable orthodontica
liance for s
ace management combinedwith anterior esthetic restorations:a case re
ortPasumon
awangnimitkul DD
1Chalerm
ol Leevailoj DD
, M
D, ABOD, FRCDT21Graduate
tudent, Esthetic Restorative and Im
lant Dentistry Program, Faculty of Dentistry,Chulalongkorn University2Esthetic Restorative and Im
lant Dentistry Program, Faculty of Dentistry, Chulalongkorn UniversityAbstract
acing in the esthetic area results in an unconfident smile. To solve this
roblem, manyalternative treatments can be used with multidisci
linary knowledge: for exam
le, orthodontictreatment and restorative treatment. The treatment
lan should be
erformed under conservativeconsideration, while the esthetic outcome should
ersist in the long term. Instead of using only
restorative treatment to close several s
aces, minor tooth movement before restorative
rocedures mayachieve a
referable result since the teeth can be realigned to the
ro
er
osition; it also requires lesstooth structure
re
aration. This case re
ort demonstrated the use of a removable orthodontic a
lianceto distribute the anterior s
ace before restoring the bilateral
eg-sha
ed lateral incisors with
orcelainlaminate veneers to close all the s
aces in the maxillary anterior area. This resulted in a naturala earance with healthy gingival tissue during the 8-month follow-u eriod. This treatment rinci le can be a lied for use in other small s acing cases.
(CU Dent J. 2012;35:131-40)Key words: esthetic; interdisci linary a roach; eg-sha ed lateral incisor; orcelain veneer;removable a
liance; s
acing132
awangnimitkul P, et al CU Dent J. 2012;35:131-40IntroductionToday, most
eo
le are concerned about theirhealth and a
earance; this includes healthy teeth anda beautiful smile, which will increase their confidencewhen out in ublic. The so-called esthetic zone in theanterior maxilla has the greatest im
act on smiledesign. Tooth anomalies occurring in this area-such asmisalignment, discoloration, or malformed and missing
teeth-can lead to unattractive smiles with non-harmonious
ink and white esthetic in the esthetic zone, whichmay sometimes reduce a
ersons confidence insmiling during their social lives.1One common esthetic roblem in the maxillaryanterior area is a
eg-sha
ed or mesiodistally deficientmaxillary lateral incisor. The definition of a
eg-sha
edlateral incisor is given in the Glossary of ProsthodonticTerms (2005) as an undersized, ta ered tooth.2Aty
ical tooth sha
e may result from an ina
ro
riate
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roliferation of the tooth bud cells during toothformation.3 Peg-sha
ed lateral incisors may causes
acing in the anterior maxilla, trans
osition ofadjacent teeth, and rolonged retention of deciduouscanines.4 The incidence of
eg-sha
ed lateral incisorsis a
roximately 2% to 5% of the
o
ulation, andoccurs more frequently in females than in males.5,6Anatomically,
eg-sha
ed lateral incisors are found
redominately on the left side of the arch.5,7There are two alternative treatments for
eg-sha
edlateral incisors. The first o
tion is to move the canineforward with a fixed orthodontic a
liance to close thes ace between the lateral incisor and canine, and thenresha
e the lateral incisor to make it a
ear morenormal. The other treatment is to maintain the caninesin Angles class I relationshi
and restore themalformed teeth with resin com
osites,
orcelainveneers or crowns. These restorations are used to closethe s
ace and change the
eg-sha
ed lateral incisorsinto their natural sha
e.8 The treatment time of thelatter method is less, and the esthetic and functionaloutcomes are satisfactorily achieved.4,9 However, insome cases the clinical situation is somewhat morecom
lex and may not be able to be corrected by only
restorative means. When teeth are severely misaligned,an orthodontic a
liance can contribute to creating the
ro
er tooth
osition
rior to any restorative treatment.Furthermore, in some cases,
eriodontal surgery maybe indicated in order to im
rove the gingival levels tocreate a more desirable symmetry and harmony of the
ink esthetic.Removable orthodontic a
liances could beconsidered as an alternative treatment for
atients witha single or a few misaligned teeth. Patients feel morecomfortable with removable a liances com ared tofixed a
liances since they can be removed occasionally.A removable a liance will not com romise the atients
oral hygiene, and it requires less clinical chair timesince the a liance is fabricated in a laboratory.10 Itcan only a
ly ti
ing force to move the misalignedtooth; therefore, the treatment needs strict su
ervisionby the dentist. Moreover, accom
lishment of thetreatment de ends on the atients coo eration. It isalso difficult to create com
lex tooth movementbecause the removable a
liance cannot achievetwo-
oint contacts on teeth, which are necessary tocontrol tooth movement in three dimensions.10,11 Inaddition, the acrylic
late may affect s
eech and causediscomfort while wearing the a
liance.10A removable a
liance with clas
s and finger
s
rings may be used for minor tooth movement in theanterior area, such as a small median diastemaa
roximately 2 millimeters or less. Palatal finger s
ringsare often used to move teeth in a mesiodistal directionin orthodontic treatment.11 O timum force forcontinuous tooth movement in a single-root anteriortooth is a
roximately 25-40 grams.10,12 Activation ofthe
alatal finger s
rings at 1.5 to 2 millimetersdistance can move the maxillary central incisor about 1millimeter in one month. Excessive force can com
licate
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Sp oe 2555;35:131-40 p p`` 133the treatment, and insufficient force can
rolong thetreatment time.10 Although removable a
liances witha finger s ring can shift the tooth to the correct osition,the tooth does not have bodily movement in the sameway as with a fixed a
liance because the finger s
ringhas only a
oint contact on the tooth. Therefore, onlythe ti
ing movement can be
erformed by removablea
liances.10Peg-sha
ed lateral incisors need restoration, suchas direct resin com
osite or
orcelain laminate veneers,to restore the tooth sha
e and close the s
ace.13,14While com osite veneers have the advantage of beinga low-cost conservative
rocedure,
orcelain laminateveneers have other advantages such as high longevity,material biocom
atibility, and a highly estheticresult.14,15 Porcelain can mimic the natural a
earanceof enamel.16 Moreover,
orcelain veneers retain lessstaining and are more durable com
ared to resincom
osite.15 Friedman and colleague re
orted that thelong-term clinical longevity of
orcelain veneers wasu
to 15 years, with only 7% failure rate due tofracture, leakage, or veneer debonding. This indicatesthat
orcelain veneers are very
redictable restorations.17
However, in order to fabricate a high-quality
orcelainveneer, teeth need to be
re
ared to allow for adequatethickness of the material. Generally a felds
athicveneer requires a minimum thickness of 0.3 millimeters.16However, the fabrication of a 0.3-millimeter-thickhigh-strength leucite-reinforced veneer is very difficult.One study revealed some cracking of 0.3-millimeter-thickveneers during cement
olymerization when the veneerswra
ed over the incisal edge.18 From these data, therecommended thickness for the veneers should be atleast 0.5 millimeter if they cover the incisal edge orinter
roximal area.18 However,
eg-sha
ed lateralincisors need minor re aration because the teeth have
enough s
ace for
orcelain veneer fabrication exce
t atthe cervical margin. ufficient tooth re aration at thecervical margin is recommended in order to avoid anovercontoured restoration.18In this case re
ort, the
atient was treated byminor tooth movement with a removable a liance todistribute the s
acing more favorably. Then estheticrestorations were
erformed by correcting the
egsha
edlateral incisors with ceramic veneers.Clinical re ortA 19-year-old male
atient was referred to theEsthetic Restorative and Im
lant Dentistry Clinic,Chulalongkorn University, for closing the s
ace in the
u
er anterior maxillary region and to change bothlateral incisors sha
e. Intraoral examination revealeds
acing between teeth 11 and 21 due to the distalmigration of tooth 21 a
roximately 0.5 millimeter,while the mesial of tooth 11 coincided with the dentaland facial midline. The shifting of tooth 21 waslikely caused by malformation of the lateral incisors.The
atient
resented with two
eg-sha
ed lateralincisors, teeth 12 and 22 (Fig. 1A). Tooth 13 wasslightly mesiolingually rotated. All of the teeth were
8/12/2019 The Use of a Removable Orthodontic
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sound and asym
tomatic. The
atient had 2 millimetersof overjet and 2 millimeters of overbite. Radiogra
hicexamination found that tooth 21 was minorly ti
edto the distal. Teeth 13 to 23 had an intact laminadura, with no
eria
ical radiolucency observed(Fig. 1B-D).Our treatment
lan was to do minor tooth movementof tooth 21 to close the median diastema (withoutmoving tooth 11) by using a removable orthodontica
liance, and then to restore both
eg-sha
ed lateralincisors with ceramic veneer facings. The orthodonticremovable a
liance was com
osed of one finger s
ringat distal of tooth 21, which generated force to movetooth 21 mesially, and one acrylic sto
at distal oftooth 11, which hel
ed stabilize the tooth 11 whentooth 21 was moved into contact. This
rocedure neededtwo weeks of force a
lication and two weeks ofstabilizing the tooth in
osition before the finalrestorations were
erformed. The case was finished by134
awangnimitkul P, et al CU Dent J. 2012;35:131-40
lacing ceramic veneers on the two lateral incisors toclose the s
ace and change the tooth sha
e. The
atientwas asked to wear a full-time retainer for three monthsto stabilize the anterior teeth and continued to wear a
art-time retainer for a year.10With this
reliminary condition, if the s
ace wasmanaged without using a removable orthodontica
liance, the median diastema would be closed byeither resin com
osite or ceramic, which might resultin unequal size of the central incisors. Under the
ro
osed treatment
lan, the two central incisors wouldnot be
re
ared. Their alignment would be correctedby means of minor tooth movement. The two
eg-sha
edlateral incisors would be the only teeth that neededrestoration. Consequently, the atient acce ted our
ro
osed treatment
lan.Fig. 1 Pretreatment. 1A, Tooth 21 aligned distally while tooth 11 coincided with
the facial and dental midline.1B-D, Radiogra hic examination revealed sound maxillary anterior teeth and tooth21 minorly ti
ed to the distal.Fig. 2 Wax-u
model was fabricated to
resent the
ossible outcome to the
atient. Sp oe 2555;35:131-40 p p`` 135Fig. 3 Minor tooth movement with removable orthodontic a
liance and tooth
re
aration. 3A, Removableorthodontic a
liance with a finger s
ring at distal of tooth 21 and an acrylicsto at distal of tooth 11.3B, The removable orthodontic a
liance was inserted in the mouth. 3C, Frontal view after minor toothmovement was achieved. 3D, Minimal
re
aration on teeth 12 and 22 without using
local anesthesia.Clinical
roceduresOn the first visit, oral examination and smileanalysis were
erformed. Then the
atients
resentdental condition was recorded, including radiogra hsof teeth 13 to 23. Im
ressions of maxillary andmandibular teeth were taken for
re
aring the studymodels.On the second visit, a wax-u model was used tocommunicate with the
atient about the treatment
lan,
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treatment
rocedures and the outcome (Fig. 2). Thenthe removable orthodontic a
liance, com
osed of onefinger s
ring and one acrylic sto
, was fabricated.On the third visit, the s ring-activated removableorthodontic a
liance was delivered, and oral hygieneinstructions were given (Fig. 3A and B).Two weeks after a
liance a
lication, the s
acebetween teeth 11 and 21 was evaluated. The s
acewas closed com
letely, as shown in Fig. 3C. Radiogra
hicexamination showed minimal alteration of theangulation of tooth 21.
hade selection for
orcelain veneers was erformed using a Vita 3D-Master hade Guide (Vident,U
A) by selecting value, chroma and hue, res
ectively.The selected shade was 2M1. Teeth 12 and 22 were
re
ared for
orcelain veneers using a conservativea
roach by removing minimal tooth structure at thecervical margins and labial surfaces, and sha
ing theincisal edges without using local anesthesia (Fig. 3D).A final im
ression was taken with light-body and
utty
olyvinyl siloxane (Flexitime, Heraeus Kulzer, U
A)using double-mixed single-im
ression technique
riorto fabricating the working model. Bite registration wastaken using Blu-Mousse (Parkell, U
A). Tem
orary
restorations were carried out using resin com
osite(shade A2, Premise; Kerr, U
A) with s
ot etching.16The tem
orary restorations were finished out ofocclusion, and the
atient was instructed to cleangently and avoid biting on these areas.A
hotogra
h with shade tab and a drawing ofthe color ma
ing were used to mimic the nature oftooth (Fig. 4A and B). Then, two Em
ress Estheticveneers (Ivoclar Vivadent, Liechtenstein) were fabricatedwith layering technique to create high translucent areasat the incisal third (Fig. 4C).Clinically, the veneers were tried in after tem
oraryveneers were removed. Resin cement (bleach shade,
NX-3 Nexus; Kerr, U
A) was used to cement both136 awangnimitkul P, et al CU Dent J. 2012;35:131-40veneers. The inner surfaces of the veneers were treatedwith 4% buffered hydrofluoric acid gel (Porcelain etchant,Bisco, U
A) for 4 minutes, and rinsed; then silane(Monobond- ; Ivoclar Vivadent, Liechtenstein) wasa
lied, and dried with warm air for 1 minute.19 Toothsurfaces were treated with 37.5%
hos
horic acid gelfor 15 seconds (Gel Etchant; Kerr, U
A) and thenrinsed. Primer and bonding agents (O tiBond FL; Kerr,U
A) were a
lied following manufacturers instruction.Bleach shade resin cement was a
lied on the innersurfaces of the veneers, which were subsequently
cemented on both teeth and light-cured for 2 minutes.After cementation, occlusal adjustment was done andexcess cement was removed. The
atient satisfied withthe result (Fig. 5). During the 8-month follow-u
eriod, the atient was recalled and the veneersmaintained their natural a
earance with healthygingival tissue (Fig. 6).DiscussionIn this case re ort, the finger s ring was designedto be used with a slightly dis
laced tooth in the mesio-distal
8/12/2019 The Use of a Removable Orthodontic
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direction, since this s
ring has minor force that onlylasts for a short
eriod. The direction of the force fromthe s
ring should be
er
endicular to the long axis ofthe tooth, and the force should ass as close to thecenter of resistance as
ossible to reduce toothsrotation movement.11 The use of a finger s
ringgenerates a center of resistance to the tooth at the middleof the root. The movement of the tooth is
er
endicularto the tangent of the tooth surface at the contact
ointof the s
ring.12 With a finger s
ring, it is not
ossibleto move both the crown and the root simultaneouslybecause the direction of the s
rings force cannot
assthe center of resistance. As a result, the root a ex willmove in the o
osite direction com
ared to the crown.12Furthermore, the finger s
ring contacts the tooth atonly one
oint, which leads the tooth to ti
mesially ordistally.11 Minor tooth movement with a finger s
ringis acce
table in the case of tooth movement of a fewmillimeters. However, control of the root is neededwhen moving the tooth crown more than 3 to 4millimeters.10 As mentioned above, these are thelimitations of a removable a
liance with finger s
ring.However, the finger s
ring is a
ro
riate in a casewhere the tooth needs u
righting in order to move the
tooth to the right
lace, and it is ina
ro
riate in a casewhere the tooth is already angulated in the desireddirection.11Orthodontically treated teeth tend to rela
se overtime, after the a
liances are removed. A few factorsare the major causes of rela
sing. In this case re
ort,Fig. 4 Color ma
ing and shade selection of tooth 22. 4A, Drawing of tooth 22, showing color ma
ing and toothcharacteristics, was sent to communicate with the laboratory technician. 4B, Photogra
h of adjacent teeth withmatched shade tab. 4C, Veneers fabricated with translucent area and characterized to mimic adjacent teeth. Sp oe 2555;35:131-40 p p`` 137
Fig. 5 Pretreatment and
osttreatment of both
eg-sha
ed lateral incisors. 5A and B, Equal s aces of teeth 12 and22 were accom
lished after tooth 21 was ti
ed mesially by using removable orthodontic a
liance. 5C andD, Natural a
earance of teeth 12 and 22 was achieved after veneer cementation.Fig. 6 Com arison hotos of retreatment (left), and 8-month follow-u (right).6A and B, The change in thefacial a
earance and the new smile refreshed the whole facial com
osition. 6C and D, The veneers gavethe atient more confidence which showed in new natural smile. 6E and F, The veneers remained innatural a
earance with healthy gingival tissue.138
awangnimitkul P, et al CU Dent J. 2012;35:131-40
the
rimary cause was
eriodontal and gingival tissuereorganization. A
revious study demonstrated that the
eriodontal ligament needs 3 to 4 months to reorganizeitself, but the collagenous and elastic fibers in thegingival tissue need 4 to 6 months to do so. Thesu
racrestal fiber can remodel extremely slowly, and maycause the tooth to dis
lace within 1 year after treatment.This is why every
atient needs to wear a full-timeretainer for at least a few months, and this should becontinued for 12 months as a
art-time retention.10
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Daily oral hygiene maintenance of the veneers issimilar to that for natural teeth. Normal toothbrushingtwice a day and flossing are recommended for dailycare. One advantage of a orcelain surface is that thereis less
laque and calculus de
osition com
ared to anatural tooth surface.16 Therefore, it is not necessary touse an ultrasonic scaler to clean the veneers. Dentistsshould also be aware that the ultrasonic scalers ti
may create roughness, scratches or chi
s on the
orcelainsurface.20 Patients should take s
ecial care when bitingon hard foods.20 The gingival margin area is im
ortant;if gingival recession occurs, the veneer margin will beex osed and contribute to unesthetic outcomes. Inaddition, the veneers should be ins
ected regularly.20For veneer
re
aration, the
eg-sha
ed lateralincisors are already undersized. They only need minor
re
aration because there is already enough s
ace forcreating the
orcelain veneers. However,
re
arationof the teeth is necessary to define the veneer marginsduring fabrication, so that they can be created with the
ro
er thickness. In addition to mimicking the translucentarea of the natural teeth, incisal reduction may be needed.Thus, restoring the
eg-sha
ed lateral incisors withveneers is a
ro
riate due to the conservative
treatment as
ect, longevity, and highly esthetic resultscom
ared to resin com
osite filling.16Communication between the dentist and laboratorytechnician is an im
ortant issue.
im
ly selectinga shade tab is inadequate for creating the desiredrestorations.21 In addition to effective communicationwith the laboratory technician, a drawing describing allthe characteristics and color ma
ing should be sentto the laboratory in combination with
ictures of theadjacent teeth and matched shade tab.16 In our case,a drawing of tooth 12, which also simulated thecharacteristics of tooth 11, was sent to the laboratorytechnician. Pronounced vertical and horizontal lines
with some white s
ots were indicated in the drawing.Highlighted edges with gray area at the incisal thirdshowed the translucent area of the teeth. A
hotogra
hwith shade tab 2M1 from the Vita 3D-Master
hadeGuide was sent at the same time.Marginal gingival recession is caused by manyfactors, including inflammatory
eriodontal disease,ageing, faulty tooth alignment, traumatic toothbrushinginjury, orthodontic forces,
ressure (bands, arch wires,clas s or denture bars) and deleterious habits.22 Themost common cause is traumatic toothbrushing injury.23The defect dominantly occurs on left canine area inright handed
atients.22 And it was found more
frequent at facial surface than
alatal side.23 Moreover,the traumatic toothbrushing habits often relate to goodoral hygiene.23 In the
resent case, small gingivaldefects were shown at marginal gingiva of teeth 22 to 24.Faulty toothbrushing technique may be the cause, asnoticed by good oral hygiene and the area of the defects.Pro
er oral hygiene instruction was given, however,the defects
ersisted after the treatment was com
leted.The atient was reinstructed and informed aboutdisadvantages of toothbrush injury. The
atient understood
8/12/2019 The Use of a Removable Orthodontic
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and attem
ted to follow the oral hygiene instruction.Although the restorations look natural and achievea highly esthetic result, their function and the
atientsoral health are the most im ortant issues. The atientmust be informed of the entire treatment
lan
rior tothe beginning of the treatment, including oral hygieneinstruction. The
atient must be aware that the focusneeds to be not only on the restored area, but also onthe entire mouth, in order to maintain the esthetica
earance and the longevity of the veneers. Sp oe 2555;35:131-40 p p`` 139ConclusionThe use of a sim le removable orthodontica
liance combined with
orcelain laminate veneerscan be used to manage s
acing in the maxillaryanterior area with
eg-sha
ed lateral incisors. Thisconservative treatment can achieve a highly estheticoutcome, with healthy gingival tissue. The treatment
rinci
les described in this case re
ort can be extendedto the treatment of other small s
acing issues
resentin other cases.References1. Van der Geld P, Oosterveld P, Van Heck G,Kuij
ers-Jagtman AM.
mile attractiveness:
self-
erce
tion and influence on
ersonality. AngleOrthod. 2007;77:759-65.2. Academy of Prosthodontics. The glossary of
rosthodontic terms. J Prosthet Dent. 2005;94:10-92.3. Arte
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chmitz JH, Coffano R, Bruschi A. Restorativeand orthodontic treatment of maxillary
egincisors: a clinical re ort. J Prosthet Dent. 2001;85:330-4.5. Meskin LH, Gorlin RJ. Agenesis and eg-sha ed
ermanent maxillary lateral incisors. J Dent Res.1963;42:1476-9.6. Alvesalo L, Portin P. The inheritance
attern ofmissing,
eg-sha
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ameshima GT. Peg-sha
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t. Louis: Mosby, 2000:418-48.11. Cobourne MT, DiBiase AT. Handbook oforthodontics. 1st ed.
t. Louis: Mosby, 2010:209-34.12. Jones ML, Oliver RG. Walther and Houstonsorthodontic notes. 5th ed. Oxford: Wright, 1994:
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133-56.13. Izgi AD, Ayna E. Direct restorative treatment of
eg-sha
ed maxillary lateral incisors with resincom osite: a clinical re ort. J Prosthet Dent.2005;93:526-9.14. Peumans M, Van Meerbeek B, Lambrechts P,Vanherle G. Porcelain veneers: a review of theliterature. J Dent. 2000;28:163-77.15. McLaren EA. Luminescent veneers. J Esthet Dent.1997;9:3-12.16. Gurel G. The science and art of
orcelain laminateveneers. Hanover Park IL, U
A: QuintessencePublishing, 2003:19-58, 302-9.17. Friedman MJ. A 15-year review of
orcelainveneer failure-a clinicians observations. Com
endContin Educ Dent. 1998;19:625-36.18. Roulet JF,
oderholm KJM, Longmate J. Effectsof treatment and storage conditions on ceramic/com
osite bond strength. J Dent Res. 1995;74:381-7.19. McLaren EA. Porcelain veneer
re
arations: to
re
or not to
re
. Inside Dent. 2006;May:76-9.20. Goldstein RE. Change your smile: discover how anew smile can transform your life. 4th ed. HanoverPark IL, U
A: Quintessence Publishing, 2009:26-43.
21. Parker RM.
hade matching for indirect restorationsin the esthetic zone. J Cosmetic Dent. 2008;23:98-104.22. Grant DA,
tern IB, Listgarten MA. Periodontics.6th ed.
t. Louis: Mosby, 1988:460-8.23. Newman MG, Takei HH, Carranza FA. Carranzasclinical
eriodontology. 9th ed. U
A: W.B.
aunders,2002:851-75.140
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