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Treatment of severe maxillary crowding using Invisalign and fixed appliances

Adult patients with severe maxillary-arch
crowding often have additional dental prob-
lems that can make their treatment even more
challenging. In such a case, an appropriate treat-
ment plan that corrects the malocclusion while
respecting the integrity of the dentition should be
developed by a multidisciplinary team.
Despite its limitations, the I nvisalign* system
has been used to treat adult orthodontic patients
with increasingly complex malocclusions.1-7 When
severe localized crowding is treated solely with
Invisalign, however, midcourse corrections or
refinements are often required. The combination
of clear aligners and conventional fixed appli-
ances can offer significant advantages, including
a reduced risk of root damage.
Clinicians who plan to use aligners to correct
severe maxillary-arch crowding in adults face two
major challenges. First, although the root positions
must be carefully controlled during extraction
space closure, this is one of the most significant
limitations of the Invisalign technique. If mesial
tipping exceeds 10-15° during space closure, a
segmental or full fixed appliance is strongly rec-
ommended to reposition the tipped teeth after the
aligner therapy. Second, in a case of severe local-
ized crowding, the thermoformed aligners may not
properly grip all the teeth to be moved. This situ-
ation calls for a fixed appliance to be used before
Invisalign therapy. The following patient illustrates
such treatment.
Case Report
A 30-year-old female patient presented with
a Class II malocclusion and a hyperdivergent skel-
etal pattern (Fig. 1, Table 1). She was particularly
concerned about the crowding of her maxillary
front teeth, and she also wanted esthetic treatment.
Intraoral examination showed “V”-shaped dental
arches with severe crowding on the upper right
side. The maxillary right canine had erupted
ectopically, and the lateral incisor was displaced
palatally in a crossbite position. The upper midline
was shifted 3mm to the right, and the lower mid-
line 1mm to the left. Mild crowding was also
present in the lower arch, with the left lateral inci-
sor in an edge-to-edge occlusion. All third molars
were present; the lower third molars were par-
tially erupted.
The upper left first premolar had a preexist-
ing restoration, but the upper right first premolar
was healthy. Because severe crowding was ob -
served only in the upper arch and the axial position
of the lower incisors was acceptable, extraction of
the two upper first premolars was considered the
most appropriate option. A combined treatment
plan was developed involving distalization of the
© 2009 JCO, Inc.
Treatment of Severe
Maxillary Crowding Using
Invisalign and Fixed Appliances
*Registered trademark of Align Technology, Inc., 881 Martin
Ave., Santa Clara, CA 95050;
Dr. G ianc otti is an Assis tant Profe ssor and Dr. Di Girolamo i s a clinical
consultant, Department of Orthodontics, Associazione Fatebenefratelli
per la Ricerca, Fatebenefratelli Hospital, Universit y of Rome “Tor
Ver gata”, Rome, Italy. E-mail Dr. Giancotti at g iancot
Dr. Di GirolamoDr. Giancotti
©2009 JCO, Inc. May not be distributed without permission.
Fig. 2 TMA** T-loops for canine retraction.
Fig. 1 30-year-old female patient
with Class II malocclusion and hy -
per divergent skeletal pattern.
maxillary canines using fixed appliances, followed
by Invisalign therapy.
After extraction of the maxillary first premo-
lars, brackets were bonded bilaterally from the
maxillary canines to the first mola rs. The canines
were retracted using T-loops in segmented .017" ×
.025" TMA** wire (Fig. 2) over a period of four
months (Fig. 3).
Norm Pretreatment Post-Treatment
SNA 82° ± 3.5° 79° 79°
SNPog 80° ± 3.5° 74° 75°
ANPog 2° ± 2.5°
S-N/ANS-PNS 8° ± 3.0°
S-N/Go-Gn 33° ± 2.5° 39° 36°
ANS-PNS/Go-Gn 25° ± 6.0° 31° 28°
U1/ANS-PNS 110° ± 6.0° 110° 109°
L1/Go-Gn 94° ± 7.0° 84° 84°
L1/A-Pog 2.0mm ± 2.0mm 5mm 5mm
Overjet 3.5mm ± 2.5mm 3mm 2mm
Overbite 2.0mm ± 2.5mm 3mm 2mm
U1/L1 132° ± 6.0° 116° 119°
**Trademark of Ormco /“A” Compa ny, 1717 W. Collins Ave.,
Orange, CA 92867;
Fig. 3 Patient after four months of canine retraction.
Treatment of Severe Maxillary Crowding Using Invisalign
The ClinCheck* projection anticipated sat-
isfactory resolution of all occlusal anomalies,
correction of the overjet and overbite, and align-
ment of the upper anterior teeth (Fig. 4). Standard
.75mm elliptical attachments were bonded to the
upper right second premolar and canine to provide
reciprocal anchorage for labial movement of the
Fig. 4 Initial ClinCheck (A) and projection of treatment outcome (B).
*Registered trademark of Align Technology, Inc., 881 Martin
Ave., Santa Clara, CA 95050;
Giancotti and Di Girolamo
upper right lateral incisor. On the left side, vertical
rectangular attachments were placed on the canine,
second premolar, and first molar to promote bodi-
ly movement during space closure. Minor reprox-
imation was required in the lower arch.
Thirty-six aligners were planned for the
upper arch and 18 for the lower arch. The patient
was seen every four to six weeks (two to four
aligners) to check for aligner fit, attachment stabil-
ity, and cooperation. The initial Invisalign phase
lasted 18 months (Fig. 5).
Because the lower left lateral incisor did not
move as intended, lingual and labial grooves were
added to the next aligner with detailing pliers. This
adjustment produced the intended rotation. The
patient needed nine refinement aligners and Class
III elastics to correct the buccal intercuspation over
the ensuing five months (Fig. 6).
The patient wore each aligner for two weeks
as directed. After 23 months of Invisalign treat-
ment, she was given clear overlay retainers to wear
in both arches at night only.
At the end of treatment, the upper anterior
teeth were aligned, and the upper right lateral inci-
sor was properly positioned (Fig. 7). No adverse
effects were observed on the adjacent teeth. The
midlines were coincident and centered in the face.
The periodontium was generally healthy, with
esthetic anterior gingival margins resulting in a
pleasant smile.
Although the angulations of the maxillary
canine roots were not ideal on the final panoram-
ic x-ray, the outcome compared favorably with
similar cases treated with fixed appliances alone.
Moreover, the roots of the upper lateral incisors
maintained a “neutral” tip, as was seen prior to
treatment. No root resorption was evident on the
final panoramic and apical x-rays.
Cephalometric analysis showed that the posi-
tions of the maxillary and mandibular incisors
changed only slightly, while the interincisal angle
increased by 3° (Table 1). The vertical dimension
was controlled to a greater extent in the upper
molars than in the lower molars, although the
intermaxillary divergence was reduced. The con-
vexity of the profile and the nasolabial angle did
not change significantly.
The potentially traumatic effects of ortho-
dontic forces should be considered when planning
treatment for adult patients. For example, apical
root resorption is often associated with extractions
Fig. 5 After 18 months of Invisalign treatment.
Fig. 6 Case refinement using Class III elastics.
Treatment of Severe Maxillary Crowding Using Invisalign
Fig. 7 A. Patient after 27 months of fixed-appliance
and Invisalign treatment (continued on next page) .
Giancotti and Di Girolamo
because of the substantial apical displacements
involved in the retraction of anterior teeth.8-12
DeShields13 and others8,10 have reported a signifi-
cant correlation between maxillary incisor retrac-
tion and root resorption. To protect the dental roots
of adult patients, most clinicians attempt to mini-
mize the amount of horizontal and vertical tooth
movement and limit the duration of treatment.
Combining fixed appliances with Invisalign
treatment is a reasonable option for a significant
number of adult patients seeking orthodontic cor-
rection of severe localized crowding. This approach
promotes and maintains the integrity and health
of dental roots and periodontal tissues, increasing
the likelihood of a good long-term outcome.
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tocol for the Invisalign appliance, J. Clin. Orthod. 41:525-547,
2. Boyd, R.L. and Vlaskalic, V.: Three-dimensional diagnosis
and or thodontic treatment of complex malocclusions with the
Invisalign appliance, Semin. Orthod. 7:274-293, 2001.
3. Duong, T. and Kuo, E.: Finishing with Invisalign, Prog.
Orthod. 7:44-55, 2006.
4. Giancotti, A.; Greco, M.; and Mampieri, G.: Extraction treat-
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7. Womack, W.R. and Day, R.H.: Surgical-orthodontic treatment
using the Invisalign system, J. Clin. Orthod. 42:237-245,
8. Beck, B. and Harris, E.F.: Apical root resorption in orthodon-
tically treated subjects: Analysis of edgewise and light wire
mechanics, Am. J. Orthod. 105:350-361, 1994.
9. McNab, S.; Battistutta, D.; Taverne, A.; and Symons, A.L.:
External apical root resorption following orthodontic treat-
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10. Parker, R.J. and Ha rris, E.F.: Directions of orthodontic tooth
movements associated with externa l apical root resorption of
the maxillary central incisor, Am. J. Orthod. 114:677-683,
11. Segal, G.R.; Schiffman, P.H.; and Tuncay, O.C.: Meta ana lysis
of the treatment-related factors of exter nal apical root resorp-
tion, Orthod. Craniofac. Res. 7:71-78, 2004.
12. Turatti, G.; Womack, R.; and Bracco, P.: Incisor intrusion with
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13. DeShields, R.W.: A study of root resorption in treated Class II,
Division I malocclusions, Angle Orthod. 39:231-245, 1969.
Fig. 7 (cont.) B. Superimposition of pre - and post-treatment cephalo-
metric tracings.
... Daarnaast geldt, hoe complexer de behandeling, hoe meer aligners nodig zullen zijn. Op basis van onderzoek van Boyd (2008) en Giancotti et al (2009). kan een indicatie worden gegeven van ongeveer 24 aligners bij een milde Klasse II-occlusie met een overbeet en crowding. ...
... kan een indicatie worden gegeven van ongeveer 24 aligners bij een milde Klasse II-occlusie met een overbeet en crowding. Wanneer de casus ingewikkelder is, bijvoorbeeld als er ook sprake is van een kruisbeet, dan kan het aantal aligners oplopen tot 45 (Boyd 2008;Giancotti et al, 2009). Bij een Klasse I-malocclusie en 4 mm crowding zijn ongeveer 15 aligners geindiceerd. ...
The aim of this research was to evaluate the efficiency and effectiveness of an orthodontic treatment with clear-aligner systems, specifically with Invisalign®. In addition to a review of the literature, 4 orthodontists and 9 patients treated with fixed orthodontic therapy and Invisalign® were interviewed. The literature showed that it is difficult to correct an extrusion, rotation or overjet with clear aligners. Often 'refinement' (additional intervention during treatment) is necessary to achieve the best possible end result. The patients interviewed experienced few limitations in their daily lives caused by the clear aligners and hardly any pain. Treatment duration was comparable to that with fixed appliances; it depended on the experience of the orthodontist, the complexity of the case and cooperation of the patient. The cost of an Invisalign® treatment is higher than that of fixed-appliance therapy. Additionally, making a plan for clear-aligner treatment often takes more time for the orthodontist than planning treatment for fixed-appliance therapy.
... Furthermore, a study assessed the limitations of orthodontic treatment using aligners alone, including reports on the efficacy of a combination technique that incorporates the use of aligners together with a fixed appliance 4) . Moreover, another study suggests that this combination technique can shorten the duration of treatments and reduce the burden on roots and periodontal tissues compared with aligner treatment alone 15) . ...
It is difficult to control corrective forces in orthodontic treatment with clear aligners. The grip of aligners on teeth is important to ensure accurate corrective forces from aligners. This study aimed to measure the gripping force of aligners under various conditions to clarify factors that influence it. We created aligners with different attachment morphologies and placement sites and different margin lengths. We developed a device to measure the mechanics involved in the removal of these aligners. The gripping force was evaluated at five different aligner removal sites on the teeth. We found that the gripping force of the aligner was the weakest on the lingual side of the first molar and strongest on the labial side of the central incisors and that the attachment morphology and placement sites affected the gripping force of aligners.
... 9 Case studies including premolar extractions emphasise this issue, since it indicated need of permanent appliances to straighten the molars, premolars, and canines at the end of aligner therapy. 10,11 Honn and Goz provided a case study of a successful Invisalign premolar extraction therapy One advantage of using the method was that it needed little bodily movement, simply small rotations, and no extrusion, intrusion, or torque movements. The effectiveness of Invisalign therapy is highly dependent on which tooth movements are necessary to address the clinical condition, as well as comprehending the appliance's indications. ...
Aesthetics is a major factor in Orthodontic treatment and it is a primary concern among patients seeking orthodontic treatment. To meet the growing aesthetic desire for an alternative to traditional braces, researchers have created a variety of alternatives, including ceramic or composite braces, lingual orthodontics, and transparent aligners. Clear aligner therapy is a treatment that consists of a set of clear dental appliances that are custom-made to fit the contour of a patient's teeth. Clear Aligners are an alternative to traditional braces that are used to guide teeth into appropriate alignment. Clear aligners, like braces, utilise a progressive force to regulate tooth movement, but without the need of metal wires or brackets.
... More recently, clear aligner technology has evolved over the past 10 years with such appliances continuously being modified to broaden the range of tooth movements they can achieve [14]. Nowadays, it is possible to correct every type of malocclusion by using aligners: deep bite, open bite, cross bites, severe crowding, Class II and Class III malocclusions [15][16][17]. In literature, a number of scientific articles including case reports show proper correction of Class II malocclusions by using aligners. ...
... 7,8 Recent improvements have allowed the use of Invisalign® also in more complex clinical conditions, thanks to innovative material and attachments, more accurate software, the introduction of a new force system, and the more extensive experience gained. [9][10][11][12][13][14][15] The aim of this work is to share a dedicated procedure for the treatment of impacted cuspids by combining the use of aligners with a conventional forced eruption technique. ...
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To recover impacted canines without esthetic issues, the aligners can be a resolutive tool allowing by pontics the camouflage of absent canines during orthodontic treatment. Knowledge of biomechanics, correct staging of dental movements, and surgery planification are strategic to achieve a good result. To recover impacted canines without esthetic issues, the aligners can be a resolutive tool allowing by pontics the camouflage of absent canines during orthodontic treatment. Knowledge of biomechanics, correct staging of dental movements, and surgery planification are strategic to achieve a good result.
When using clear aligners, if distalization greater than 3 mm is required, there is no real predictable procedure to follow. The aim of this article is to show with two clinical cases the biomechanics of distalizing lower molars with mini-implant anchorage and aligners.
Introduction This case report describes the treatment of a 21-year-old man who presented in an orthodontic office for treatment but lived in a city 100 miles away and wanted the orthognathic surgery in another state in America. The patient presented with an anterior open bite and skeletal Class III relationship. Methods The treatment plan included: (1) effective and careful communication of the treatment plan with the patient, orthodontist and oral and maxillofacial surgeon; (2) pre-surgical alignment and levelling of the teeth in both arches with Invisalign; (3) a long-distance communication between the orthodontist and the surgeon for surgical plan with virtual surgical planning (VSP Orthognathics; 3D Systems, ) online; (4) maxillary advancement (LeFort I osteotomy) with mandibular set-back (bilateral sagittal split osteotomy); (5) postsurgical correction of the malocclusion with clear brackets and aligners; and (6) retention and final small tooth movement adjustments with aligners/clear retainers. Results The anterior open bite was treated, crowding was eliminated in the upper and lower anterior segment, correction of skeletal and dental Class III malocclusion was obtained, mandibular plane angle was reduced and facial profile improved. Conclusions The results suggest that aesthetic and functional results can be achieved with long-distance communication of two specialties and with the combined use of clear aligners and clear fixed appliances.
A critical aspect of the orthodontic treatment is patient cooperation, especially in nonextraction treatment. The introduction of the use of miniscrews in orthodontics and the development of protocols integrated with the Bidimensional Technique (MGBM System) have overcome these difficulties, while maintaining high-quality treatment results. The treatment is divided into three phases and traditional anchoring systems, such as extraoral traction and elastics are replaced by miniscrews. This chapter describes the clinical steps highlighting the mechanotherapy used in the phases of the treatment.
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Clear aligners have become the treatment of choice for treating mild to moderate malocclusions in patients who are concerned for esthetics compromise of fixed orthodontic appliance treatment. Two case reports are presented to demonstrate the effectiveness of clear aligners in resolving crowding due to orthodontic relapse and spacing in the anterior teeth region. In both the cases, predicted results were achieved using clear aligners which was simple and convenient for both the patient and the clinician.
Clear aligners have become the treatment of choice for treating mild to moderate malocclusions in patients who are concerned for esthetics compromise of fixed orthodontic appliance treatment. Two case reports are presented to demonstrate the effectiveness of clear aligners in resolving crowding due to orthodontic relapse and spacing in the anterior teeth region. In both the cases, predicted results were achieved using clear aligners which was simple and convenient for both the patient and the clinician.
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This study investigated the association of appliance type and tooth extraction with the incidence of external apical root resorption (EARR) of posterior teeth following orthodontic treatment. Pre- and posttreatment orthopantomograms were compared for 97 patients and a 4-grade ordinal scale used to measure EARR. The incidence of EARR was positively associated with tooth position (P < .001), appliance type (P = .038), and extractions (P = .001). This was observed in an overall analysis mutually adjusted for the effects of age at start of treatment, pretreatment overbite and overjet, use of headgear, tooth extraction, and type of appliance. The incidence of EARR was 2.30 times higher for Begg appliances compared with edgewise, and it was 3.72 times higher where extractions were performed.
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The Invisalign method is gaining an increasing interest as an alternative treatment option in adult patients and in difficult orthodontic cases. The aim of this work is to show a class II malocclusion with severe crowding in the upper and lower arches treated with the extraction of the upper first premolars performed by means of Invisalign. The alignment phase was successfully completed but the space closure achieved with crown tipping and without correct root inclination making a further fixed appliance phase necessary.
Of the several modes of tooth movement, pressure from intrusive forces seems the most likely to cause external apical root resorption (EARR). This has been demonstrated for incisors in human beings and molars in laboratory animals. The present study examined full-banded adolescent patients and scored the degrees of in-treatment root resorption throughout the dentition. Just Class I cases with four first premolar extractions were used. Equal samples of conventional Begg and Tweed treated cases were examined with 1:1 sex ratios (total n = 83). No difference between the Begg and Tweed techniques and no sex difference was found in any of the 30 univariate tests, even though power analysis indicated a strong likelihood of finding a difference if one existed. By using multiple linear regression, significant decreases in length (EARR) were found for those roots systematically intruded in this Class I malocclusion, notably the mesial root of the maxillary first molar and the distal root of the mandibular first molar. Even though some of the present cases had been in "active" treatment up to 6 years, we found no significant association between duration of treatment and degree or amount of EARR.
External apical root resorption is a multifactorial problem encountered in all disciplines of dentistry, but it is most commonly seen in cases treated orthodontically. Specific tooth movements that are most likely to exacerbate external apical root resorption are poorly understood. Purpose of the present investigation was twofold: (1) to quantify apical and incisal movements of the maxillary central incisor in the sagittal and vertical planes from cephalograms and (2) to use stepwise multivariate linear regression analyses to see which tooth movements and skeletodental relationships are most predictive of external apical root resorption. The sample consisted of 110 adolescents with similar pretreatment malocclusions (Class I crowded or bimaxillary protrusive) and treatment planned similarly (extraction of four first premolars) by experienced private practitioners. Each of three practitioners used a different orthodontic appliance; the sample was divided proportionately into cases treated with Tweed standard edgewise technique, Begg lightwire technique, and Roth-prescription straightwire technique. Lateral cephalograms were analyzed at the start, middle, and end of treatment. There was no statistical difference in average external apical root resorption between sexes or among techniques. Measures of tooth movement were highly predictive, explaining up to 90% of the variation in root resorption. Apical and incisal vertical movements and increase in incisor proclination were the strong predictors of external apical root resorption for each regression model. Incisor intrusion with increase in lingual root torque together were the strongest predictors of external apical root resorption. In contrast, distal bodily retraction, extrusion, or lingual crown tipping had no discernible effect.
To elucidate possible treatment-related etiological factors--such as, duration of treatment and apical displacement--for external root resorption. Meta-analysis of the available English-language literature. Papers with a sample size > 10, fixed appliances, pre- and post-operative radiographs, and apical displacement recorded were included. History of trauma, prior root resorption and endodontic treatment were excluded. Appropriateness of these selections was tested with a 'funnel plot' analysis. Correlations between root resorption, apical displacement, and treatment duration. Mean apical root resorption was strongly correlated with total apical displacement (r = 0.822) and treatment duration (r = 0.852). The treatment-related causes of root resorption appear to be the total distance the apex had moved and the time it took.
Unlabelled: Finishing in orthodontics can be challenging and can involve use of various techniques and armamentarium. This article reports a study that evaluates a procedure for using a thicker Aligner at the end of treatment to aide in finishing and also to determine if this would reduce the need for additional "case refinement" Aligners at the end of treatment. Background: Align Technology has developed the Invisalign System, which is a series of clear plastic appliances ("aligners") that move the patient's teeth in small increments from their original state to a final, treated state. The Invisalign System uses a computer as a tool to assist in creating a series of sequential movements to assure light and consistent forces on the patient's teeth.