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Class I open bite: A case report
Class I open bite: A case report Roberto Herndndez-Orsini, DMD, MPH, MS* Birmingham, Ala.
The patient was a 25-year-old white woman in good general health. She had a mildly convex facial profile with a hyperdivergent facial pattern and a mildly acute nasolabial angle. She had a Class I malocclusion complicated by an anterior open bite tendency and a moderate lip incompetence. The patient had a mild Class III molar relationship on both sides and an overjet of 3 mm (Figs. 1-4). In addition, she had mild upper and lower crowding (3 to 4 ram). The patient's chief complaint was procumbency of anterior teeth, and she thought she had "too many teeth for [her] mouth." The cephalometric evaluation showed a Class I skeletal pattern, although Class III features were present (ANB = 1.5, Wits = - 7 mm). She had a long lower facial height, a high mandibular plane angle, a 9 mm lip incompetence, and a 2 mm anterior open bite (Fig. 5).
TREATMENT PLAN The limitations of orthodontic therapy alone were explained to the patient. Stability of her malocclusion by compensating dental movement was questionable. In addition, the *FormerGraduate Student in Orthodontics, Universityof Alabama Schoolof Dentistry; now AssistantProfessor, Universityof Puerto Rico School of Dentistry, San Juan, Puerto Rico. 814116333
Table I. C u s t o m c e p h a l o m e t r i c analysis
SNA (degrees) SNB (degrees) ANB (degrees) Wits (ram) LFtt (%) i" to NA (mm) T to NA (degrees) T to PP (degrees) I to NB (mm) I to NB (degrees) Occlusal plan to SN (degrees) Mandibular plant to SN (degrees) ! to MP (degrees) 1 to A-Po (mm)
Fig. 1. A through C, Pretreatment facial views. 100
82.4 80.9 1.6 - 1.0 54.0 4.3
77.0 75.5 1.5 -7.0 62.0 10.0
81.0 78.0 3.0 0.5 61.0 5.5
22.8
31.0
23.0
112.0
115.0
1 ! 1.0
4.0
7.0
6.0
25.3
27.0
27.0
14.4
26.5
16.0
32.9
36.0
33.0
90.0
94.5
97.0
2.7
5.5
2.0
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Case report
101
Fig. 2. A through E, Pretreatment intraoral views.
patient further expressed her desire for an esthetic change in her appearance. Orthognathic surgery was explained to the patient, and a prediction of changes to be achieved with and without surgery were addressed in the consultation. Combined orthodontic and orthognathic surgery procedures were chosen by the patient for correction of her malocclusion. The request was made for nonextraction treatment, if possible. After the treatment consultation, the following treatment objectives were proposed: 1. Correction of the open bite by impaction of the maxilla superiorly and posteriorly.
2. Reduction of the anterior lower facial height by impaction of the maxilla to allow mandibular autorotation. 3. Decreased proclination of maxillary incisors by rotation of the anterior maxillary segment during impaction, then a decrease in the amount of anterior torque. 4. Elimination of the mild upper and lower crowding. Edgewise 0.018 × 0.025-inch appliances were used in the following sequence: i. The maxillary and mandibular arches were both
102
Am. J. Orthod. Dentofac. Orthop. Februao' 1991
Hernandez-Orshli
Fig. 3. A through E, Pretreatment study models.
W
i
1 ,dl Fig. 4. Pretreatment panoramic radiograph.
Volume 99 Number 2
C a s e report
>"
5.5m
,-7==
Fig. 5. Cephalometric tracing of pretreatment lateral radiograph.
Fig. 6. Presurgical orthodontic dental movement superimposition. The maxilla was superimposed in ANS-PNS and the mandibular outlines in the symphysis and mandibular plane.
Fig. 7. A through C. Posttreatment facial views.
103
104
Am..I, Orthod. Dentofac. Orthop. February 1991
Hernandez-Orsini
.
o
I
,
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.
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Fig. 8. A through E, Posttreatment intraoral views. banded and bonded at the same time. Brackets on the upper canines were placed upside down to achieve mesial root movement. 2. The upper arch was leveled and aligned in anterior and posterior segments. Space for the surgical cut of about 3 mm was the goal. The lower arch was leveled continuously. 3. At the time of orthognathic surgery, the maxilla was divided into three segments, with posterior maxillary impaction and rotation of the anterior segment. In addition, a mandibular advancement and a sliding genioplasty were performed.
4. During the postsurgical orthodontic treatment, both arches were coordinated and any remaining space distal to the upper canines after maxillary surgery was closed. In addition, the upper canines were rebonded to obtain proper angulation of their roots.
TREATMENT PROGRESSION Total active treatment took 17 months. Presurgical orthodontic treatment lasted 6 months. The lower arch was leveled continuously and the upper arch in three segments (7-4 , 3 3, 4-7). The presurgical orthodontic tooth movement is shown in Fig. 6. Three millimeters of space was opened distal
Volume 99 Number 2
Case report
Fig. 9. A through E, Posttreatmentstudy models.
Fig. 10. Posttreatment panoramic radiograph.
105
106
Am. J.
Hernandez-Orsini
Orthod, Dentofac. Orthop. February 1991
C
,~o=2i I-0.5~
Fig. 11. Cephalometric tracing of posttreatment lateral radiograph.
Fig. 12. Cephalometric superimposition showing treatment results.
to the upper canines on each side for the surgical cut. In addition, the roots of the canines were moved mesially to avoid damage during the surgical procedure. The surgical procedure was successfully performed. As soon as the surgical splint was removed, the upper canines were rebonded to position their roots in the ideal inclination. Six months of orthodontic treatment followed the surgical procedure. See Figs. 7 through 12 for treatment results. For 8 months during the retention phase, the patient main-
tained an excellent occlusion, and the surgical results appeared to be stable, but no records were available at this time other than the finighing orthodontic records (Table I). Reprint requests to:
Dr. Roberto Hernfindez-Orsini Canino Olejandfino #4 Villa Clementina Guaynabo, PR 00657
The patient was a 25-year-old white woman in good general health. She had a mildly convex facial profile with a hyperdivergent facial pattern and a mildly acute nasolabial angle. She had a Class I malocclusion complicated by an anterior open bite tendency and a moderate lip incompetence. The patient had a mild Class III molar relationship on both sides and an overjet of 3 mm (Figs. 1-4). In addition, she had mild upper and lower crowding (3 to 4 ram). The patient's chief complaint was procumbency of anterior teeth, and she thought she had "too many teeth for [her] mouth." The cephalometric evaluation showed a Class I skeletal pattern, although Class III features were present (ANB = 1.5, Wits = - 7 mm). She had a long lower facial height, a high mandibular plane angle, a 9 mm lip incompetence, and a 2 mm anterior open bite (Fig. 5).
TREATMENT PLAN The limitations of orthodontic therapy alone were explained to the patient. Stability of her malocclusion by compensating dental movement was questionable. In addition, the *FormerGraduate Student in Orthodontics, Universityof Alabama Schoolof Dentistry; now AssistantProfessor, Universityof Puerto Rico School of Dentistry, San Juan, Puerto Rico. 814116333
Table I. C u s t o m c e p h a l o m e t r i c analysis
SNA (degrees) SNB (degrees) ANB (degrees) Wits (ram) LFtt (%) i" to NA (mm) T to NA (degrees) T to PP (degrees) I to NB (mm) I to NB (degrees) Occlusal plan to SN (degrees) Mandibular plant to SN (degrees) ! to MP (degrees) 1 to A-Po (mm)
Fig. 1. A through C, Pretreatment facial views. 100
82.4 80.9 1.6 - 1.0 54.0 4.3
77.0 75.5 1.5 -7.0 62.0 10.0
81.0 78.0 3.0 0.5 61.0 5.5
22.8
31.0
23.0
112.0
115.0
1 ! 1.0
4.0
7.0
6.0
25.3
27.0
27.0
14.4
26.5
16.0
32.9
36.0
33.0
90.0
94.5
97.0
2.7
5.5
2.0
Volume 99 Number 2
Case report
101
Fig. 2. A through E, Pretreatment intraoral views.
patient further expressed her desire for an esthetic change in her appearance. Orthognathic surgery was explained to the patient, and a prediction of changes to be achieved with and without surgery were addressed in the consultation. Combined orthodontic and orthognathic surgery procedures were chosen by the patient for correction of her malocclusion. The request was made for nonextraction treatment, if possible. After the treatment consultation, the following treatment objectives were proposed: 1. Correction of the open bite by impaction of the maxilla superiorly and posteriorly.
2. Reduction of the anterior lower facial height by impaction of the maxilla to allow mandibular autorotation. 3. Decreased proclination of maxillary incisors by rotation of the anterior maxillary segment during impaction, then a decrease in the amount of anterior torque. 4. Elimination of the mild upper and lower crowding. Edgewise 0.018 × 0.025-inch appliances were used in the following sequence: i. The maxillary and mandibular arches were both
102
Am. J. Orthod. Dentofac. Orthop. Februao' 1991
Hernandez-Orshli
Fig. 3. A through E, Pretreatment study models.
W
i
1 ,dl Fig. 4. Pretreatment panoramic radiograph.
Volume 99 Number 2
C a s e report
>"
5.5m
,-7==
Fig. 5. Cephalometric tracing of pretreatment lateral radiograph.
Fig. 6. Presurgical orthodontic dental movement superimposition. The maxilla was superimposed in ANS-PNS and the mandibular outlines in the symphysis and mandibular plane.
Fig. 7. A through C. Posttreatment facial views.
103
104
Am..I, Orthod. Dentofac. Orthop. February 1991
Hernandez-Orsini
.
o
I
,
;
,,,
,
~'
!t
.
.
"
~,,,,~
'
,
;
.... ~,.(.,':,
k,
'
. ) "a..J"
I"
j
j "k
I' ,
;
j , , , <:
i~" .
:,
\ •
~L
4"
t
•
I
•
Fig. 8. A through E, Posttreatment intraoral views. banded and bonded at the same time. Brackets on the upper canines were placed upside down to achieve mesial root movement. 2. The upper arch was leveled and aligned in anterior and posterior segments. Space for the surgical cut of about 3 mm was the goal. The lower arch was leveled continuously. 3. At the time of orthognathic surgery, the maxilla was divided into three segments, with posterior maxillary impaction and rotation of the anterior segment. In addition, a mandibular advancement and a sliding genioplasty were performed.
4. During the postsurgical orthodontic treatment, both arches were coordinated and any remaining space distal to the upper canines after maxillary surgery was closed. In addition, the upper canines were rebonded to obtain proper angulation of their roots.
TREATMENT PROGRESSION Total active treatment took 17 months. Presurgical orthodontic treatment lasted 6 months. The lower arch was leveled continuously and the upper arch in three segments (7-4 , 3 3, 4-7). The presurgical orthodontic tooth movement is shown in Fig. 6. Three millimeters of space was opened distal
Volume 99 Number 2
Case report
Fig. 9. A through E, Posttreatmentstudy models.
Fig. 10. Posttreatment panoramic radiograph.
105
106
Am. J.
Hernandez-Orsini
Orthod, Dentofac. Orthop. February 1991
C
,~o=2i I-0.5~
Fig. 11. Cephalometric tracing of posttreatment lateral radiograph.
Fig. 12. Cephalometric superimposition showing treatment results.
to the upper canines on each side for the surgical cut. In addition, the roots of the canines were moved mesially to avoid damage during the surgical procedure. The surgical procedure was successfully performed. As soon as the surgical splint was removed, the upper canines were rebonded to position their roots in the ideal inclination. Six months of orthodontic treatment followed the surgical procedure. See Figs. 7 through 12 for treatment results. For 8 months during the retention phase, the patient main-
tained an excellent occlusion, and the surgical results appeared to be stable, but no records were available at this time other than the finighing orthodontic records (Table I). Reprint requests to:
Dr. Roberto Hernfindez-Orsini Canino Olejandfino #4 Villa Clementina Guaynabo, PR 00657