- Email: [email protected]
A significant transverse discrepancy: A case with a high mandibular plane angle, a severe maxillary arch length deficiency, and significant transverse discrepancy
ABO CASE REPORT
A significant transverse discrepancy: A case with a high mandibular plane angle, a severe maxillary arch length deficiency, and significant transverse discrepancy Steven L. Cureton, DMD, MSa Evans, Ga. A case report presented to the American Board of Orthodontics in partial fulfillment of the requirements for certification. (Am J Orthod Dentofacial Orthop 1998;114:307-10.)
RESUME´
Patient: No. 8 Born: Feb. 4, 1978 Age: 15 years, 9 months PRETREATMENT RECORDS (Nov. 9, 1993) Diagnosis
Category no. 8: a case with a high mandibular plane angle, a severe maxillary arch length deficiency, and significant transverse discrepancy: a posterior crossbite that requires full appliance treatment. Treatment plan ● ● ● ● ●
To eliminate maxillary and mandibular crowding To correct the bilateral posterior crossbite To eliminate the Cr to occlusion slide To improve the overbite and overjet To correct the dental midlines
Treatment ●
Surgically assisted rapid palatal expansion (fixed Hyrax appliance) ● Extraction of maxillary first premolars, mandibular right first premolar and mandibular left second premolar ● High-pull headgear ● 0.018 ⫻ 0.025 Edgewise appliances
POSTTREATMENT RECORDS (as of Mar. 4, 1996) Retention: Maxillary removable retainer and mandibular 3 ⴛ 3 fixed retainer ● ●
HISTORY AND ETIOLOGY
The patient was a 15 year 9 month old male whose chief complaint was, “I don’t like my fangs.” His dental history was unremarkable with the exception of a hyperactive gag reflex. He was diagnosed as having Attention Deficit Syndrome (ADS) and was taking 20 mg of Ritalin every morning and 10 mg every night. The patient also had juvenile arthritis and was taking 500 mg of Naprosyn daily. The cause of his malocclusion is assumed to be hereditary in nature. His mother was Asian and his father was white. His mother displayed a class III malocclusion. DIAGNOSIS ● ● ● ● ●
Time frame ● ● ●
Initiated: Nov. 16, 1993 Completed: Dec. 20, 1995 Active treatment time: 25 months
The opinions and assertions contained herein are the private ones of the writer and are not to be construed as reflecting the views of the U.S. Army or the Military Service at large. a Orthodontic Department, Fort Gordan, Ga. Reprint requests to: Steven L. Cureton, 909 Burlington Dr., Evans, GA 30809 8/4/84817
Completed: Ongoing Retention time: Ongoing
● ● ●
Class I malocclusion (mesial drift of maxillary left molar) Class III tendency skeletal relationship (Fig. 1) Constricted maxilla with bilateral posterior crossbite tendency End-on incisor relationship with no overbite Maxillary midline 1 mm to the right, mandibular midline 2 mm to the left of the facial midline High mandibular plane angle (Fig. 1) (Table I) Severe maxillary arch length discrepancy Slide to the left from CR to habitual occlusion
SPECIFIC OBJECTIVES OF TREATMENT (Skeletal and Oral) ●
Treat to a physiologic skeletal and dental relationship with centric relationship equal to centric occlusion. 307
308 Cureton
Fig. 1. Cephalometric tracing at beginning of treatment. (See Table I for values.)
● ● ● ● ●
Relieve the maxillary and mandibular arch length discrepancies Provide canine guidance in lateral excursions and incisal guidance in protrusive movements Correct the crossbite Establish an ideal overbite and overjet, correct the midline discrepancy Improve the esthetics and function of the teeth through proper alignment and interdigitation
TREATMENT PROGRESS
Treatment was initiated by placing appliances on the maxillary and mandibular arches. A 16 ⫻ 22 titanium molybdenum alloy (TMA) spring was placed between the maxillary central incisors to begin separating the roots before the surgical expansion. A Hyrax appliance was cemented to the maxillary first molars and first premolars. After the surgically assisted expansion, the patient activated the appliance one turn every other day. He was seen
American Journal of Orthodontics and Dentofacial Orthopedics September 1998
at 1 week intervals until adequate expansion was achieved. The appliance was stabilized for 3 months before its removal. The mandibular right first premolar and left second premolar were extracted during the surgical expansion procedure. This extraction pattern was chosen to assist in the correction of the mandibular midline and to provide space for maximum protraction of the left posterior segment to obtain a class I molar relationship. A removable mandibular lingual arch wire slightly constricted was used to bring the mandibular left first molar into the existing arch form. The maxillary right and left first premolars were extracted after the Hyrax was removed. A removable transpalatal arch wire was immediately placed to hold the expansion. High pull headgear was initiated with 14 to 16 hours of wear requested. A 9 month panographic x-ray revealed minor root resorption of some teeth. I decided to limit my arch wires to multistranded Niti, and TMA wires in an effort to limit the amount of root resorption. Once the mandibular left molar was in a good transverse position, the lingual arch was removed and a 17 ⫻ 25 TMA closing loop arch wire was inserted to protract the mandibular left first molar. A maxillary 17 ⫻ 25 TMA closing loop arch wire was used to close the remaining space in the maxillary arch. Second molars were banded but were stepped out of occlusion. Class 2 elastics were initiated on the left side and class 3 elastics were worn simultaneously on the right side. The patient’s third molars were extracted in August of 1995. Once all spaces were closed and molars in a good class I relationship, maxillary and mandibular 16 ⫻ 22 TMA wires were inserted in both arches and short class 3 elastics were used to bring the teeth into their final occlusion. The appliances were removed in December 1995 and clear retainers inserted. Holes were drilled in the lingual acrylic and alastics placed to move the teeth into ideal positions. Strategic bends were placed on the outer bow to assist in the correction producing ideal alignment. RESULTS ACHIEVED (Skeletal and Dental)
The functional and esthetic results achieved in this case are very acceptable. Very little growth occurred during the treatment period. As a result of the retraction of the mandibular incisors, lip prominence was reduced somewhat (Fig. 2). Overbite was accomplished mostly by extrusion of the mandibular incisors. The vertical height of the maxillary molars was maintained. The mandibular plane angle did not increase during treatment. All pretreatment objectives were met in this case including excellent mid-
Cureton 309
American Journal of Orthodontics and Dentofacial Orthopedics Volume 114, No. 3
Fig. 2. Lateral cephalometric tracing at time of appliance removal. Fig. 3. Superimposed pretreatment and posttreatment tracings. Note uprighting and eruption of lower incisors, improving lip contour. No change in mandibular plane angle.
Table I. The American Board of Orthodontics cephalometric summary Area of study Cranial base Maxilla to cranial base Mandible to cranial base Maxilla to mandible relations Vertical height
Maxillary and mandibular incisor position
Soft tissue
Measurement
Norm
A
Difference
B
Difference
N-S-Ar SNA SNB NPog-FH ANB WITS SN-GoGn FMA SN-Occ Plane Y Axis U1-NA (mm) U1-NA (deg) L1-NB (mm) L1-NB (deg) IMPA U1-L1 (deg) L1-APog Esthetic Plane Upper lip (mm) Lower lip (mm)
123° 81° 79° 89° 2° 0 mm 32° 24° 16° 59° 4 mm 22° 4 mm 25° 91° 135° 1 mm
124° 82° 80° 89° 2° ⫺7 mm 40° 31° 21° 62° 5 mm 16° 8 mm 28° 90° 133° 6 mm
1° 1° 1° – – ⫺7 mm 8° 7° 5° 3° 1 mm ⫺6° 4 mm 3° ⫺1° ⫺2° 5 mm
124° 81° 79° 90° 2° ⫺3 mm 40° 31° 19° 62° 5 mm 21° 5 mm 22° 84° 135° 2 mm
1° – – 1° – ⫺3 mm 8° 7° 3° 3° 1 mm ⫺1° 1 mm ⫺3° ⫺7° – 1 mm
⫺4 mm ⫺2 mm
⫺2 mm 1 mm
2 mm 3 mm
⫺4 mm ⫺3 mm
– ⫺1 mm
C
Difference
310 Cureton
American Journal of Orthodontics and Dentofacial Orthopedics September 1998
line coordination and elimination of the cross-bite (Fig. 3). The centric relationship to habitual occlusion disharmony was also eliminated. A well-seated posterior occlusion with no balancing interferences was established. The health of the teeth and periodontium remained very good. No evidence of enamel decalcification was noted. Apical root resorption occurred primarily on the maxillary incisors and on all premolars. RETENTION
Retention was established in this case with maxillary and mandibular removable clear retainers immediately after appliance removal. A bonded mandibular lingual retainer consisting of a preadapted 0.0215 multistranded twisted wire
was placed. A month later a maxillary removable retainer was inserted with instructions for 24 hour/day wear. After 1 year of full time wear, the patient was instructed to wear the retainer only at night. FINAL EVALUATION
Overall results in this case were very good. Root resorption was noted early in treatment and was addressed by using light forces with flexible arch wires. Even without this propensity for root resorption, flexible arch wires would have been considered due to the patient’s extremely high mandibular plane angle. The final relationship exhibits good function and esthetics. The patient and his parents are very pleased with the final outcome.
BOUND VOLUMES AVAILABLE TO SUBSCRIBERS
Bound volumes of the American Journal of Orthodontics and Dentofacial Orthopedics are available to subscribers (only) for the 1998 issues from the Publisher, at a cost of $87.00 ($104.86 Canada and $98.00 international) for Vol. 113 (January-June) and Vol. 114 (July-December). Shipping charges are included. Each bound volume contains a subject and author index and all advertising is removed. Copies are shipped within 60 days after publication of the last issue of the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact Mosby, Inc., Subscription Services, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; telephone (314)453-4351 or (800)325-4177. Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular Journal subscription.
Fig. 4. Facial and intraoral photographs at beginning of orthodontic treatment; patient was aged 15 years, 1 month.
Fig. 5. A, Beginning applicance placement with TMA spring between maxillary central incisors to begin separating the central incisor roots, preparatory to the surgically assisted expansion. B, Modified lower removable retainer with alastics placed in holes drilled in acrylic, in place. These, together with adjustments in the labial wire bow, were used to correct the imibrication. Note bends in labial bow. C, Position of mandibular teeth, immediately after appliance removal, with slight residual irregularity. D, Correction achieved with active retainer.
Fig. 6. Facial and intraoral photographs after active appliance removal; patient was aged 18 years, 21 months.
A significant transverse discrepancy: A case with a high mandibular plane angle, a severe maxillary arch length deficiency, and significant transverse discrepancy Steven L. Cureton, DMD, MSa Evans, Ga. A case report presented to the American Board of Orthodontics in partial fulfillment of the requirements for certification. (Am J Orthod Dentofacial Orthop 1998;114:307-10.)
RESUME´
Patient: No. 8 Born: Feb. 4, 1978 Age: 15 years, 9 months PRETREATMENT RECORDS (Nov. 9, 1993) Diagnosis
Category no. 8: a case with a high mandibular plane angle, a severe maxillary arch length deficiency, and significant transverse discrepancy: a posterior crossbite that requires full appliance treatment. Treatment plan ● ● ● ● ●
To eliminate maxillary and mandibular crowding To correct the bilateral posterior crossbite To eliminate the Cr to occlusion slide To improve the overbite and overjet To correct the dental midlines
Treatment ●
Surgically assisted rapid palatal expansion (fixed Hyrax appliance) ● Extraction of maxillary first premolars, mandibular right first premolar and mandibular left second premolar ● High-pull headgear ● 0.018 ⫻ 0.025 Edgewise appliances
POSTTREATMENT RECORDS (as of Mar. 4, 1996) Retention: Maxillary removable retainer and mandibular 3 ⴛ 3 fixed retainer ● ●
HISTORY AND ETIOLOGY
The patient was a 15 year 9 month old male whose chief complaint was, “I don’t like my fangs.” His dental history was unremarkable with the exception of a hyperactive gag reflex. He was diagnosed as having Attention Deficit Syndrome (ADS) and was taking 20 mg of Ritalin every morning and 10 mg every night. The patient also had juvenile arthritis and was taking 500 mg of Naprosyn daily. The cause of his malocclusion is assumed to be hereditary in nature. His mother was Asian and his father was white. His mother displayed a class III malocclusion. DIAGNOSIS ● ● ● ● ●
Time frame ● ● ●
Initiated: Nov. 16, 1993 Completed: Dec. 20, 1995 Active treatment time: 25 months
The opinions and assertions contained herein are the private ones of the writer and are not to be construed as reflecting the views of the U.S. Army or the Military Service at large. a Orthodontic Department, Fort Gordan, Ga. Reprint requests to: Steven L. Cureton, 909 Burlington Dr., Evans, GA 30809 8/4/84817
Completed: Ongoing Retention time: Ongoing
● ● ●
Class I malocclusion (mesial drift of maxillary left molar) Class III tendency skeletal relationship (Fig. 1) Constricted maxilla with bilateral posterior crossbite tendency End-on incisor relationship with no overbite Maxillary midline 1 mm to the right, mandibular midline 2 mm to the left of the facial midline High mandibular plane angle (Fig. 1) (Table I) Severe maxillary arch length discrepancy Slide to the left from CR to habitual occlusion
SPECIFIC OBJECTIVES OF TREATMENT (Skeletal and Oral) ●
Treat to a physiologic skeletal and dental relationship with centric relationship equal to centric occlusion. 307
308 Cureton
Fig. 1. Cephalometric tracing at beginning of treatment. (See Table I for values.)
● ● ● ● ●
Relieve the maxillary and mandibular arch length discrepancies Provide canine guidance in lateral excursions and incisal guidance in protrusive movements Correct the crossbite Establish an ideal overbite and overjet, correct the midline discrepancy Improve the esthetics and function of the teeth through proper alignment and interdigitation
TREATMENT PROGRESS
Treatment was initiated by placing appliances on the maxillary and mandibular arches. A 16 ⫻ 22 titanium molybdenum alloy (TMA) spring was placed between the maxillary central incisors to begin separating the roots before the surgical expansion. A Hyrax appliance was cemented to the maxillary first molars and first premolars. After the surgically assisted expansion, the patient activated the appliance one turn every other day. He was seen
American Journal of Orthodontics and Dentofacial Orthopedics September 1998
at 1 week intervals until adequate expansion was achieved. The appliance was stabilized for 3 months before its removal. The mandibular right first premolar and left second premolar were extracted during the surgical expansion procedure. This extraction pattern was chosen to assist in the correction of the mandibular midline and to provide space for maximum protraction of the left posterior segment to obtain a class I molar relationship. A removable mandibular lingual arch wire slightly constricted was used to bring the mandibular left first molar into the existing arch form. The maxillary right and left first premolars were extracted after the Hyrax was removed. A removable transpalatal arch wire was immediately placed to hold the expansion. High pull headgear was initiated with 14 to 16 hours of wear requested. A 9 month panographic x-ray revealed minor root resorption of some teeth. I decided to limit my arch wires to multistranded Niti, and TMA wires in an effort to limit the amount of root resorption. Once the mandibular left molar was in a good transverse position, the lingual arch was removed and a 17 ⫻ 25 TMA closing loop arch wire was inserted to protract the mandibular left first molar. A maxillary 17 ⫻ 25 TMA closing loop arch wire was used to close the remaining space in the maxillary arch. Second molars were banded but were stepped out of occlusion. Class 2 elastics were initiated on the left side and class 3 elastics were worn simultaneously on the right side. The patient’s third molars were extracted in August of 1995. Once all spaces were closed and molars in a good class I relationship, maxillary and mandibular 16 ⫻ 22 TMA wires were inserted in both arches and short class 3 elastics were used to bring the teeth into their final occlusion. The appliances were removed in December 1995 and clear retainers inserted. Holes were drilled in the lingual acrylic and alastics placed to move the teeth into ideal positions. Strategic bends were placed on the outer bow to assist in the correction producing ideal alignment. RESULTS ACHIEVED (Skeletal and Dental)
The functional and esthetic results achieved in this case are very acceptable. Very little growth occurred during the treatment period. As a result of the retraction of the mandibular incisors, lip prominence was reduced somewhat (Fig. 2). Overbite was accomplished mostly by extrusion of the mandibular incisors. The vertical height of the maxillary molars was maintained. The mandibular plane angle did not increase during treatment. All pretreatment objectives were met in this case including excellent mid-
Cureton 309
American Journal of Orthodontics and Dentofacial Orthopedics Volume 114, No. 3
Fig. 2. Lateral cephalometric tracing at time of appliance removal. Fig. 3. Superimposed pretreatment and posttreatment tracings. Note uprighting and eruption of lower incisors, improving lip contour. No change in mandibular plane angle.
Table I. The American Board of Orthodontics cephalometric summary Area of study Cranial base Maxilla to cranial base Mandible to cranial base Maxilla to mandible relations Vertical height
Maxillary and mandibular incisor position
Soft tissue
Measurement
Norm
A
Difference
B
Difference
N-S-Ar SNA SNB NPog-FH ANB WITS SN-GoGn FMA SN-Occ Plane Y Axis U1-NA (mm) U1-NA (deg) L1-NB (mm) L1-NB (deg) IMPA U1-L1 (deg) L1-APog Esthetic Plane Upper lip (mm) Lower lip (mm)
123° 81° 79° 89° 2° 0 mm 32° 24° 16° 59° 4 mm 22° 4 mm 25° 91° 135° 1 mm
124° 82° 80° 89° 2° ⫺7 mm 40° 31° 21° 62° 5 mm 16° 8 mm 28° 90° 133° 6 mm
1° 1° 1° – – ⫺7 mm 8° 7° 5° 3° 1 mm ⫺6° 4 mm 3° ⫺1° ⫺2° 5 mm
124° 81° 79° 90° 2° ⫺3 mm 40° 31° 19° 62° 5 mm 21° 5 mm 22° 84° 135° 2 mm
1° – – 1° – ⫺3 mm 8° 7° 3° 3° 1 mm ⫺1° 1 mm ⫺3° ⫺7° – 1 mm
⫺4 mm ⫺2 mm
⫺2 mm 1 mm
2 mm 3 mm
⫺4 mm ⫺3 mm
– ⫺1 mm
C
Difference
310 Cureton
American Journal of Orthodontics and Dentofacial Orthopedics September 1998
line coordination and elimination of the cross-bite (Fig. 3). The centric relationship to habitual occlusion disharmony was also eliminated. A well-seated posterior occlusion with no balancing interferences was established. The health of the teeth and periodontium remained very good. No evidence of enamel decalcification was noted. Apical root resorption occurred primarily on the maxillary incisors and on all premolars. RETENTION
Retention was established in this case with maxillary and mandibular removable clear retainers immediately after appliance removal. A bonded mandibular lingual retainer consisting of a preadapted 0.0215 multistranded twisted wire
was placed. A month later a maxillary removable retainer was inserted with instructions for 24 hour/day wear. After 1 year of full time wear, the patient was instructed to wear the retainer only at night. FINAL EVALUATION
Overall results in this case were very good. Root resorption was noted early in treatment and was addressed by using light forces with flexible arch wires. Even without this propensity for root resorption, flexible arch wires would have been considered due to the patient’s extremely high mandibular plane angle. The final relationship exhibits good function and esthetics. The patient and his parents are very pleased with the final outcome.
BOUND VOLUMES AVAILABLE TO SUBSCRIBERS
Bound volumes of the American Journal of Orthodontics and Dentofacial Orthopedics are available to subscribers (only) for the 1998 issues from the Publisher, at a cost of $87.00 ($104.86 Canada and $98.00 international) for Vol. 113 (January-June) and Vol. 114 (July-December). Shipping charges are included. Each bound volume contains a subject and author index and all advertising is removed. Copies are shipped within 60 days after publication of the last issue of the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Payment must accompany all orders. Contact Mosby, Inc., Subscription Services, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; telephone (314)453-4351 or (800)325-4177. Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular Journal subscription.
Fig. 4. Facial and intraoral photographs at beginning of orthodontic treatment; patient was aged 15 years, 1 month.
Fig. 5. A, Beginning applicance placement with TMA spring between maxillary central incisors to begin separating the central incisor roots, preparatory to the surgically assisted expansion. B, Modified lower removable retainer with alastics placed in holes drilled in acrylic, in place. These, together with adjustments in the labial wire bow, were used to correct the imibrication. Note bends in labial bow. C, Position of mandibular teeth, immediately after appliance removal, with slight residual irregularity. D, Correction achieved with active retainer.
Fig. 6. Facial and intraoral photographs after active appliance removal; patient was aged 18 years, 21 months.