HHS Public Access Author manuscript Author Manuscript
J Clin Orthod. Author manuscript; available in PMC 2017 August 28. Published in final edited form as: J Clin Orthod. 2016 May ; 50(5): 276–289.
Differential Molar Intrusion with Skeletal Anchorage in Open-Bite Treatment Dr. CHEOL-HO PAIK, DDS, PhD, Clinical Associate Professor, Department of Orthodontics, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea
Author Manuscript
Dr. RYAN McCOMB, DMD, MS, and Private practice of orthodontics in Los Angeles Dr. CHRISTINE HONG, DMD, MS Assistant Professor, Department of Orthodontics, UCLA School of Dentistry, 10833 Le Conte Ave., Los Angeles, CA 90095 Anterior open bite has been considered a complex malocclusion to treat because of the initial difficulty in closing the bite and the subsequent challenge of retaining bite closure.1 Proper diagnosis is necessary to develop an effective treatment plan with appropriate retention of the newly established bite.2
Author Manuscript
Among the surgical and nonsurgical approaches proposed for treatment of open-bite malocclusion—including miniplates, multiloop edgewise archwire therapy, passive posterior bite blocks, functional appliances, active vertical correctors, vertical-pull chin cups, and glossectomy—most are incapable of achieving substantial bite closure.2–4 Although it has been postulated that every 1mm of intrusive vertical movement of the molars results in about 3mm of bite closure by means of counterclockwise mandibular rotation,5 the actual amount of bite closure is less than 3mm in some clinical cases.
Author Manuscript
In recent years, molar intrusion by means of temporary anchorage devices (TADs) has become the key to resolving anterior open bite.6 Compared to other orthodontic anchorage devices, TADs are relatively simple to insert, less traumatic, and more secure under optimal force loads.7,8 Moreover, intrusion of the posterior teeth with skeletal anchorage has been shown to be stable—a critical advantage in treatment planning because of the high frequency of relapse in adults.7–9 Several authors have also proposed that orofacial myofunctional therapy10 or other muscle training and habituation exercises11 can contribute to the closure of open-bite malocclusions and help prevent relapse. The most important steps involved in open-bite treatment with TADs are a proper diagnosis of the etiologic factors causing the malocclusion and a complete assessment of the underlying dental and skeletal manifestations. The clinician must first determine whether the molar intrusion should be performed in the mandible, the maxilla, or, in severe cases, both. This article illustrates cases using all three options.
PAIK et al.
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Author Manuscript
Case 1 Lower-Molar Intrusion A 26-year-old female presented with the chief complaint of crowding and an anterior open bite (Fig. 1). Clinical examination indicated a dolichofacial growth pattern and a convex profile. At rest, the patient had no incisor display; on smiling, she showed about 80% of her upper incisors. She had a slight bilateral Class III molar relationship, upper and lower crowding, a bilateral posterior crossbite, and an open bite from the first premolars forward, measuring 5mm at the central incisors.
Author Manuscript
Because of the steep occlusal plane and relative lack of incisor display at rest, the treatment plan involved extraction of the upper and lower second premolars and lower-molar intrusion (Fig. 2). After the extractions, both arches were banded and bonded with preadjusted .022″ × .028″ ceramic brackets. Leveling and alignment took seven months. At that point, 1.3mm × 6.5mm TADs* were inserted bilaterally between the lower first and second premolars; intrusion of the lower molars and retraction of the anterior segment were started on .019″ × .025″ stainless steel archwires (Fig. 3). During molar intrusion, lingual crown torque was added to the lower archwire to prevent buccal tipping of the molars. Total treatment time was 20 months (Fig. 4). Although the patient’s convex profile improved due to the counterclockwise mandibular rotation resulting from lower-molar intrusion, she later underwent a genioplasty to improve her weak chin.
Case 2 Author Manuscript
Upper-Molar Intrusion A 16-year-old female presented with the chief complaint of an anterior open bite (Fig. 5). Clinical examination revealed a flat profile with paranasal concavity. On smiling, the patient showed about 90% of her upper incisors. We noted a bilateral Class I molar relationship, upper and lower crowding, a constricted anterior maxilla, and an open bite from the second premolars forward, measuring 3mm at the central incisors. The patient was treated with a nonextraction approach involving a Hyrax**-type maxillary expander (Fig. 6). Upper-molar intrusion was selected given her relatively normal occlusal plane and marked incisor display (Fig. 7).
Author Manuscript
After five months of expansion, a single 1.5mm × 6mm TAD was inserted in the midpalate, and .019″ × .025″ stainless steel wires were placed. Intrusion of the upper molars was initiated with elastic power chain from the midpalatal TAD to soldered hooks on a transpalatal arch (TPA), which also prevented lingual tipping of the molars (Fig. 8). Uppermolar intrusion was achieved in six months, and the TPA was then removed.
*Biomaterials Korea, Seoul, Korea; biomk2013.koreasme.com. **Dentaurum, Inc., Newtown, PA; www.dentaurum.com.
J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 3
Author Manuscript
Total treatment time was 20 months. Post-treatment records confirmed successful anterior bite closure and counterclockwise mandibular rotation (Fig. 9).
Case 3 Upper- and Lower-Molar Intrusion A 22-year-old male presented with an anterior open bite and bilateral posterior edge-to-edge bite (Fig. 10). He remarked that he was told in middle school to delay orthognathic surgery. Clinical examination indicated an extreme dolichofacial growth pattern, a convex profile, and mentalis strain on lip closure. At rest, the patient had no incisor display; on smiling, he showed about 90% of his upper incisors. He had a bilateral Class III molar relationship, moderate upper and lower crowding, a bilateral posterior edge-to-edge bite, and an open bite from the first molars forward, measuring 1–4mm at the central incisors.
Author Manuscript
Considering the severity of the open bite and mandibular plane angle, the case was treated with extraction of the upper and lower first premolars followed by simultaneous intrusion of the upper and lower molars (Fig. 11). Leveling and alignment, working up from .010″ nickel titanium arch-wires to .019″ × .025″ stainless steel archwires, took eight months.
Author Manuscript
A midpalatal 1.8mm × 5mm TAD was then inserted, a TPA was placed, and power chain was tied from a lateral hook on the TPA around the midpalatal TAD to another hook on the opposite side (Fig. 12). This created an intrusive force on both upper molars, while the TPA prevented tipping of the upper molars. At the same time, 1.5mm × 6mm TADs were placed bilaterally between the lower first and second molars. Continuous power thread from the mandibular buccal TADs was wound around the archwire at the first molars and connected to hooks soldered mesial to the canines. Exaggerated buccal root torque of about 45° prevented buccal tipping of the posterior dentition. Successful intrusion of the upper and lower molars occurred in six months, and a final overbite of 2mm was achieved. Total treatment time was 39 months (Fig. 13). Retention records taken two and a half years after completion of treatment demonstrate the stability of the correction (Fig. 14). After instruction in masticatory muscle exercises and orofacial myo-functional therapy, the patient has been able to maintain his treatment results.
Discussion
Author Manuscript
When skeletal anchorage is used to treat anterior open bite, lower-molar intrusion is preferred in three clinical situations. If the occlusal plane is steep, intrusion of the upper molars would further steepen the occlusal plane and potentially compromise the balance of incisal, cuspal, and condylar guidance.12 If the incisor display is inadequate, lower-molar intrusion will help preserve it. If there is a lack of adequate overjet, lower-molar intrusion is indicated to allow simultaneous molar intrusion and retraction of the lower dentition in coordination with mandibular autorotation. If none of the above conditions are present, upper-molar intrusion is the method of choice, since TAD placement in the midpalatal area is simpler, poses fewer risks, and is more stable. In a severe case where a primary goal is to close the mandibular plane angle, simultaneous J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 4
Author Manuscript
intrusion of both the upper and lower molars is the optimal approach.13 This allows the clinician to maximize the benefits of molar intrusion by significantly reducing the mandibular plane angle, improving mandibular prominence, and thus closing a severe open bite.
Author Manuscript
The retention protocol is one of the most important factors ensuring long-term stability of a severe open-bite correction. Masticatory muscle exercises and orofacial myofunctional therapy have been shown to be helpful in maintaining closure of an open bite by means of a reduction in the ratio of lower-anterior to total facial height and in the gonial angle, as well as an increase in true mandibular rotation.14 The masticatory muscle exercise regimen involves clenching at 80% of maximum force for five seconds, followed by five seconds of rest, for a total of six cycles, five times a day.11 Orofacial myofunctional therapy includes selective exercises for normalizing oro-facial muscles during rest, swallowing, eating, and drinking, along with exercises similar to the remedial tongue-thrust program of Weiss and van Houten.15 Although such exercises require considerable time and patient compliance, they are an important adjunct to the effective treatment of anterior open bite.
References
Author Manuscript Author Manuscript
1. Huang G. Long-term stability of anterior open bite therapy: A review, Semin. Orthod. 2002; 8:162– 172. 2. Beane RA Jr. Nonsurgical management of the anterior open bite: A review of the options. Semin Orthod. 1999; 5:275–283. [PubMed: 10860064] 3. Kim YH. Anterior openbite and its treatment with multiloop edgewise archwire. Angle Orthod. 1987; 57:290–321. [PubMed: 3479033] 4. Kim YH, Han UK, Lim DD, Serraon ML. Stability of anterior openbite correction with multiloop edgewise archwire therapy: A cephalometric follow-up study. Am J Orthod. 2000; 118:43–54. 5. Kuhn RJ. Control of anterior vertical dimension and proper selection of extraoral anchorage. Angle Orthod. 1968; 38:340–349. [PubMed: 5246797] 6. Kuroda S, Sakai Y, Tamamura N, Deguchi T, Takano-Yamamoto T. Treatment of severe anterior open bite with skeletal anchorage in adults: Comparison with orthognathic surgery outcomes. Am J Orthod. 2007; 132:599–605. 7. Park YC, Lee HA, Choi NC, Kim DH. Open bite correction by intrusion of posterior teeth with miniscrews. Angle Orthod. 2008; 78:699–710. [PubMed: 18302471] 8. Park HS, Jeong SH, Kwon OW. Factors affecting the clinical success of screw implants used as orthodontic anchorage. Am J Orthod. 2006; 130:18–25. 9. Paik CH, Ahn SJ, Nahm DS. Correction of Class II deep overbite and dental and skeletal asymmetry with 2 types of palatal miniscrews. Am J Orthod. 2007; 131:S106–S116. 10. Smithpeter J, Covell D Jr. Relapse of anterior open bites treated with orthodontic appliances with and without orofacial myofunctional therapy. Am J Orthod. 2010; 137:605–614. 11. English JD, Olfert KDG. Masticatory muscle exercise as an adjunctive treatment for open bite malocclusions, Semin. Orthod. 2005; 11:164–169. 12. Paik, CH., Park, IK., Woo, YJ., Kim, TW. Orthodontic Miniscrew Implants: Clinical Applications. Mosby; St. Louis: 2008. 13. Paik CH, Woo YJ, Boyd RL. Treatment of an adult patient with vertical maxillary excess using miniscrew fixation. J Clin Orthod. 2003; 37:423–428. [PubMed: 14519904] 14. Parks LR, Buschang PH, Alexander RA, Dechow P, Rossouw PE. Masticatory exercise as an adjunctive treatment for hyperdivergent patients. Angle Orthod. 2007; 77:457–462. [PubMed: 17465653] 15. Weiss CE, van Houten JT. A remedial program for tongue-thrust, Am. J Orthod. 1972; 62:499–506.
J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 5
Author Manuscript Author Manuscript Author Manuscript
Fig. 1.
Case 1. 26-year-old female patient with anterior open bite and bilateral posterior crossbite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 6
Author Manuscript Fig. 2.
Author Manuscript
Case 1. Lower-molar intrusion with skeletal anchorage planned, considering patient’s lack of incisor display.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 7
Author Manuscript Fig. 3.
Author Manuscript
Case 1. After seven months of initial leveling and alignment, 1.3mm × 6.5mm temporary anchorage devices* (TADs) placed bilaterally between lower first and second premolars, with .019″ × .025″ stainless steel wires used for intrusion of lower molars and retraction of anterior segment.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 8
Author Manuscript Author Manuscript Author Manuscript
Fig. 4.
Case 1. A. Patient after 20 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript Author Manuscript
Fig. 5.
Case 2. 16-year-old female patient with anterior open bite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Fig. 6.
Case 2. After three months of treatment with Hyrax**-type maxillary expander.
Author Manuscript Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript Fig. 7.
Case 2. Upper-molar intrusion with skeletal anchorage planned, considering patient’s relatively normal occlusal plane and marked incisor display.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 12
Author Manuscript Fig. 8.
Author Manuscript
Case 2. After five months of expansion, 1.5mm × 6mm TAD inserted in midpalate, .019″ × .025″ stainless steel wires placed, and intrusion of upper molars initiated with elastic power chain from TAD to soldered hooks on transpalatal arch (TPA).
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 13
Author Manuscript Author Manuscript Author Manuscript
Fig. 9.
Case 2. A. Patient after 20 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript Author Manuscript
Fig. 10.
Case 3. 22-year-old male patient with anterior open bite and bilateral posterior edge-to-edge bite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript
Fig. 11.
Case 3. Intrusion of upper and lower molars with skeletal anchorage planned, considering patient’s severe open bite and mandibular plane angle.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Fig. 12.
Author Manuscript
Case 3. After eight months of initial leveling and alignment, 1.8mm × 5mm TAD inserted in midpalate, and 1.5mm × 6mm TADs placed bilaterally between lower first and second molars. For upper-molar intrusion, power chain tied from lateral hook on TPA around midpalatal TAD to hook on opposite side. For lower-molar intrusion, continuous power thread from buccal TADs wound around archwire at first molars and connected to soldered hooks mesial to canines
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript Author Manuscript
Fig. 13.
Case 3. A. Patient after 39 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Author Manuscript Author Manuscript Author Manuscript
Fig. 14.
Case 3. A. Patient two and half years after completion of treatment. B. Superimposition of cepha-lometric tracings after debonding and two and half years after completion of treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
J Clin Orthod. Author manuscript; available in PMC 2017 August 28. Published in final edited form as: J Clin Orthod. 2016 May ; 50(5): 276–289.
Differential Molar Intrusion with Skeletal Anchorage in Open-Bite Treatment Dr. CHEOL-HO PAIK, DDS, PhD, Clinical Associate Professor, Department of Orthodontics, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea
Author Manuscript
Dr. RYAN McCOMB, DMD, MS, and Private practice of orthodontics in Los Angeles Dr. CHRISTINE HONG, DMD, MS Assistant Professor, Department of Orthodontics, UCLA School of Dentistry, 10833 Le Conte Ave., Los Angeles, CA 90095 Anterior open bite has been considered a complex malocclusion to treat because of the initial difficulty in closing the bite and the subsequent challenge of retaining bite closure.1 Proper diagnosis is necessary to develop an effective treatment plan with appropriate retention of the newly established bite.2
Author Manuscript
Among the surgical and nonsurgical approaches proposed for treatment of open-bite malocclusion—including miniplates, multiloop edgewise archwire therapy, passive posterior bite blocks, functional appliances, active vertical correctors, vertical-pull chin cups, and glossectomy—most are incapable of achieving substantial bite closure.2–4 Although it has been postulated that every 1mm of intrusive vertical movement of the molars results in about 3mm of bite closure by means of counterclockwise mandibular rotation,5 the actual amount of bite closure is less than 3mm in some clinical cases.
Author Manuscript
In recent years, molar intrusion by means of temporary anchorage devices (TADs) has become the key to resolving anterior open bite.6 Compared to other orthodontic anchorage devices, TADs are relatively simple to insert, less traumatic, and more secure under optimal force loads.7,8 Moreover, intrusion of the posterior teeth with skeletal anchorage has been shown to be stable—a critical advantage in treatment planning because of the high frequency of relapse in adults.7–9 Several authors have also proposed that orofacial myofunctional therapy10 or other muscle training and habituation exercises11 can contribute to the closure of open-bite malocclusions and help prevent relapse. The most important steps involved in open-bite treatment with TADs are a proper diagnosis of the etiologic factors causing the malocclusion and a complete assessment of the underlying dental and skeletal manifestations. The clinician must first determine whether the molar intrusion should be performed in the mandible, the maxilla, or, in severe cases, both. This article illustrates cases using all three options.
PAIK et al.
Page 2
Author Manuscript
Case 1 Lower-Molar Intrusion A 26-year-old female presented with the chief complaint of crowding and an anterior open bite (Fig. 1). Clinical examination indicated a dolichofacial growth pattern and a convex profile. At rest, the patient had no incisor display; on smiling, she showed about 80% of her upper incisors. She had a slight bilateral Class III molar relationship, upper and lower crowding, a bilateral posterior crossbite, and an open bite from the first premolars forward, measuring 5mm at the central incisors.
Author Manuscript
Because of the steep occlusal plane and relative lack of incisor display at rest, the treatment plan involved extraction of the upper and lower second premolars and lower-molar intrusion (Fig. 2). After the extractions, both arches were banded and bonded with preadjusted .022″ × .028″ ceramic brackets. Leveling and alignment took seven months. At that point, 1.3mm × 6.5mm TADs* were inserted bilaterally between the lower first and second premolars; intrusion of the lower molars and retraction of the anterior segment were started on .019″ × .025″ stainless steel archwires (Fig. 3). During molar intrusion, lingual crown torque was added to the lower archwire to prevent buccal tipping of the molars. Total treatment time was 20 months (Fig. 4). Although the patient’s convex profile improved due to the counterclockwise mandibular rotation resulting from lower-molar intrusion, she later underwent a genioplasty to improve her weak chin.
Case 2 Author Manuscript
Upper-Molar Intrusion A 16-year-old female presented with the chief complaint of an anterior open bite (Fig. 5). Clinical examination revealed a flat profile with paranasal concavity. On smiling, the patient showed about 90% of her upper incisors. We noted a bilateral Class I molar relationship, upper and lower crowding, a constricted anterior maxilla, and an open bite from the second premolars forward, measuring 3mm at the central incisors. The patient was treated with a nonextraction approach involving a Hyrax**-type maxillary expander (Fig. 6). Upper-molar intrusion was selected given her relatively normal occlusal plane and marked incisor display (Fig. 7).
Author Manuscript
After five months of expansion, a single 1.5mm × 6mm TAD was inserted in the midpalate, and .019″ × .025″ stainless steel wires were placed. Intrusion of the upper molars was initiated with elastic power chain from the midpalatal TAD to soldered hooks on a transpalatal arch (TPA), which also prevented lingual tipping of the molars (Fig. 8). Uppermolar intrusion was achieved in six months, and the TPA was then removed.
*Biomaterials Korea, Seoul, Korea; biomk2013.koreasme.com. **Dentaurum, Inc., Newtown, PA; www.dentaurum.com.
J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 3
Author Manuscript
Total treatment time was 20 months. Post-treatment records confirmed successful anterior bite closure and counterclockwise mandibular rotation (Fig. 9).
Case 3 Upper- and Lower-Molar Intrusion A 22-year-old male presented with an anterior open bite and bilateral posterior edge-to-edge bite (Fig. 10). He remarked that he was told in middle school to delay orthognathic surgery. Clinical examination indicated an extreme dolichofacial growth pattern, a convex profile, and mentalis strain on lip closure. At rest, the patient had no incisor display; on smiling, he showed about 90% of his upper incisors. He had a bilateral Class III molar relationship, moderate upper and lower crowding, a bilateral posterior edge-to-edge bite, and an open bite from the first molars forward, measuring 1–4mm at the central incisors.
Author Manuscript
Considering the severity of the open bite and mandibular plane angle, the case was treated with extraction of the upper and lower first premolars followed by simultaneous intrusion of the upper and lower molars (Fig. 11). Leveling and alignment, working up from .010″ nickel titanium arch-wires to .019″ × .025″ stainless steel archwires, took eight months.
Author Manuscript
A midpalatal 1.8mm × 5mm TAD was then inserted, a TPA was placed, and power chain was tied from a lateral hook on the TPA around the midpalatal TAD to another hook on the opposite side (Fig. 12). This created an intrusive force on both upper molars, while the TPA prevented tipping of the upper molars. At the same time, 1.5mm × 6mm TADs were placed bilaterally between the lower first and second molars. Continuous power thread from the mandibular buccal TADs was wound around the archwire at the first molars and connected to hooks soldered mesial to the canines. Exaggerated buccal root torque of about 45° prevented buccal tipping of the posterior dentition. Successful intrusion of the upper and lower molars occurred in six months, and a final overbite of 2mm was achieved. Total treatment time was 39 months (Fig. 13). Retention records taken two and a half years after completion of treatment demonstrate the stability of the correction (Fig. 14). After instruction in masticatory muscle exercises and orofacial myo-functional therapy, the patient has been able to maintain his treatment results.
Discussion
Author Manuscript
When skeletal anchorage is used to treat anterior open bite, lower-molar intrusion is preferred in three clinical situations. If the occlusal plane is steep, intrusion of the upper molars would further steepen the occlusal plane and potentially compromise the balance of incisal, cuspal, and condylar guidance.12 If the incisor display is inadequate, lower-molar intrusion will help preserve it. If there is a lack of adequate overjet, lower-molar intrusion is indicated to allow simultaneous molar intrusion and retraction of the lower dentition in coordination with mandibular autorotation. If none of the above conditions are present, upper-molar intrusion is the method of choice, since TAD placement in the midpalatal area is simpler, poses fewer risks, and is more stable. In a severe case where a primary goal is to close the mandibular plane angle, simultaneous J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 4
Author Manuscript
intrusion of both the upper and lower molars is the optimal approach.13 This allows the clinician to maximize the benefits of molar intrusion by significantly reducing the mandibular plane angle, improving mandibular prominence, and thus closing a severe open bite.
Author Manuscript
The retention protocol is one of the most important factors ensuring long-term stability of a severe open-bite correction. Masticatory muscle exercises and orofacial myofunctional therapy have been shown to be helpful in maintaining closure of an open bite by means of a reduction in the ratio of lower-anterior to total facial height and in the gonial angle, as well as an increase in true mandibular rotation.14 The masticatory muscle exercise regimen involves clenching at 80% of maximum force for five seconds, followed by five seconds of rest, for a total of six cycles, five times a day.11 Orofacial myofunctional therapy includes selective exercises for normalizing oro-facial muscles during rest, swallowing, eating, and drinking, along with exercises similar to the remedial tongue-thrust program of Weiss and van Houten.15 Although such exercises require considerable time and patient compliance, they are an important adjunct to the effective treatment of anterior open bite.
References
Author Manuscript Author Manuscript
1. Huang G. Long-term stability of anterior open bite therapy: A review, Semin. Orthod. 2002; 8:162– 172. 2. Beane RA Jr. Nonsurgical management of the anterior open bite: A review of the options. Semin Orthod. 1999; 5:275–283. [PubMed: 10860064] 3. Kim YH. Anterior openbite and its treatment with multiloop edgewise archwire. Angle Orthod. 1987; 57:290–321. [PubMed: 3479033] 4. Kim YH, Han UK, Lim DD, Serraon ML. Stability of anterior openbite correction with multiloop edgewise archwire therapy: A cephalometric follow-up study. Am J Orthod. 2000; 118:43–54. 5. Kuhn RJ. Control of anterior vertical dimension and proper selection of extraoral anchorage. Angle Orthod. 1968; 38:340–349. [PubMed: 5246797] 6. Kuroda S, Sakai Y, Tamamura N, Deguchi T, Takano-Yamamoto T. Treatment of severe anterior open bite with skeletal anchorage in adults: Comparison with orthognathic surgery outcomes. Am J Orthod. 2007; 132:599–605. 7. Park YC, Lee HA, Choi NC, Kim DH. Open bite correction by intrusion of posterior teeth with miniscrews. Angle Orthod. 2008; 78:699–710. [PubMed: 18302471] 8. Park HS, Jeong SH, Kwon OW. Factors affecting the clinical success of screw implants used as orthodontic anchorage. Am J Orthod. 2006; 130:18–25. 9. Paik CH, Ahn SJ, Nahm DS. Correction of Class II deep overbite and dental and skeletal asymmetry with 2 types of palatal miniscrews. Am J Orthod. 2007; 131:S106–S116. 10. Smithpeter J, Covell D Jr. Relapse of anterior open bites treated with orthodontic appliances with and without orofacial myofunctional therapy. Am J Orthod. 2010; 137:605–614. 11. English JD, Olfert KDG. Masticatory muscle exercise as an adjunctive treatment for open bite malocclusions, Semin. Orthod. 2005; 11:164–169. 12. Paik, CH., Park, IK., Woo, YJ., Kim, TW. Orthodontic Miniscrew Implants: Clinical Applications. Mosby; St. Louis: 2008. 13. Paik CH, Woo YJ, Boyd RL. Treatment of an adult patient with vertical maxillary excess using miniscrew fixation. J Clin Orthod. 2003; 37:423–428. [PubMed: 14519904] 14. Parks LR, Buschang PH, Alexander RA, Dechow P, Rossouw PE. Masticatory exercise as an adjunctive treatment for hyperdivergent patients. Angle Orthod. 2007; 77:457–462. [PubMed: 17465653] 15. Weiss CE, van Houten JT. A remedial program for tongue-thrust, Am. J Orthod. 1972; 62:499–506.
J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 5
Author Manuscript Author Manuscript Author Manuscript
Fig. 1.
Case 1. 26-year-old female patient with anterior open bite and bilateral posterior crossbite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 6
Author Manuscript Fig. 2.
Author Manuscript
Case 1. Lower-molar intrusion with skeletal anchorage planned, considering patient’s lack of incisor display.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 7
Author Manuscript Fig. 3.
Author Manuscript
Case 1. After seven months of initial leveling and alignment, 1.3mm × 6.5mm temporary anchorage devices* (TADs) placed bilaterally between lower first and second premolars, with .019″ × .025″ stainless steel wires used for intrusion of lower molars and retraction of anterior segment.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 8
Author Manuscript Author Manuscript Author Manuscript
Fig. 4.
Case 1. A. Patient after 20 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 9
Author Manuscript Author Manuscript Author Manuscript
Fig. 5.
Case 2. 16-year-old female patient with anterior open bite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 10
Author Manuscript Fig. 6.
Case 2. After three months of treatment with Hyrax**-type maxillary expander.
Author Manuscript Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 11
Author Manuscript Author Manuscript Fig. 7.
Case 2. Upper-molar intrusion with skeletal anchorage planned, considering patient’s relatively normal occlusal plane and marked incisor display.
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 12
Author Manuscript Fig. 8.
Author Manuscript
Case 2. After five months of expansion, 1.5mm × 6mm TAD inserted in midpalate, .019″ × .025″ stainless steel wires placed, and intrusion of upper molars initiated with elastic power chain from TAD to soldered hooks on transpalatal arch (TPA).
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 13
Author Manuscript Author Manuscript Author Manuscript
Fig. 9.
Case 2. A. Patient after 20 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
Page 14
Author Manuscript Author Manuscript Author Manuscript
Fig. 10.
Case 3. 22-year-old male patient with anterior open bite and bilateral posterior edge-to-edge bite before treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Fig. 11.
Case 3. Intrusion of upper and lower molars with skeletal anchorage planned, considering patient’s severe open bite and mandibular plane angle.
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PAIK et al.
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Author Manuscript Fig. 12.
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Case 3. After eight months of initial leveling and alignment, 1.8mm × 5mm TAD inserted in midpalate, and 1.5mm × 6mm TADs placed bilaterally between lower first and second molars. For upper-molar intrusion, power chain tied from lateral hook on TPA around midpalatal TAD to hook on opposite side. For lower-molar intrusion, continuous power thread from buccal TADs wound around archwire at first molars and connected to soldered hooks mesial to canines
Author Manuscript Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
PAIK et al.
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Fig. 13.
Case 3. A. Patient after 39 months of treatment. B. Superimposition of pre- and posttreatment cephalometric tracings.
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Fig. 14.
Case 3. A. Patient two and half years after completion of treatment. B. Superimposition of cepha-lometric tracings after debonding and two and half years after completion of treatment.
Author Manuscript J Clin Orthod. Author manuscript; available in PMC 2017 August 28.
