functional appliance therapy - jimd.in · Functional Appliance Therapy: ... Various treatment...
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DOI: http://dx.doi.org/10.18320/JIMD/201502.03204 Journal of International Medicine and Dentistry 2015; 2(3): 204-208 JOURNAL OF INTERNATIONAL MEDICINE AND DENTISTRY To search……………..to know………..…….to share p-ISSN: 2454-8847 e-ISSN: 2350-045X Case report Functional Appliance Therapy: A Case Report Maimoona Abdul Kader, 1 Shahnaz Mahamood, 2 Hashim Ali 3 Abstract: Various treatment approaches are available for management of class II malocclusion. Functional jaw orthopaedics in growing individuals can result in a broad beautiful smile, an excellent functional occlusion and noticeably improvement in profile. Following is a case report of a patient with twin block appliance in early permanent dentition period. Significant results can be obtained with proper case selection and patient compliance. Key words: Class II malocclusion, Functional appliance, Twin block appliance Introduction: Functional appliances are those which produce both skeletal and dental changes through force generated by muscles 1 . In 1977, functional appliance therapy evolved with the development of twin block appliance by Dr. William Clark, representing significant transition from one piece appliance to twin appliance that promotes normal function 2 . The goal of twin block therapy was to produce a technique that could increase the growth response to functional mandibular protrusion by using an appliance system that is simple, comfortable and aesthetically acceptable to patients. 3 The occlusal inclined plane is the fundamental functional mechanism of the natural dentition. Occlusal forces that are transmitted through the dentition provide a constant proprioceptive stimulus to influence the rate of growth and the trabecular structure of the supporting bone. 3,4 As Twin blocks are bite-blocks that effectively modify the occlusal inclined plane to induce favourably directed occlusal forces by causing a functional mandibular displacement, they had been chosen as the mode of treatment in the case mentioned. Case Report: A 11-year-old pre-adolescent female came to the department with a complaint of forwardly placed upper front teeth. On extra-oral examination, the patient was mesoprosopic facial form with convex facial profile. The nasolabial angle was acute and the chin recessive with incompetent lips with an interlabial gap of 5 mm, and horizontal growth pattern (Image I). The clinical FMA was low. She had positive VTO on advancement of the mandible to edge to edge bite (Image II & III). On functional examination, perioral muscle activity was normal. Incisor exposure on smile was 7mm. On intra-oral examination (Image IV), the patient was in the early permanent dentition, it showed Angle’s class II molar relation, class II canine relation bilaterally, Bellard’s class II Div I incisor relationship and overjet of 9mm, and lower dental midline shifted to right by 2mm with the facial midline (Image V) The overbite was increased to 5 mm (70% Deep bite). The case was diagnosed as Class II skeletal malocclusion with mandibular deficiency and maxillary dental proclination. The lateral cephalometric findings (Image VI) were an increased ANB (5°) with normal SNA
Transcript of functional appliance therapy - jimd.in · Functional Appliance Therapy: ... Various treatment...
DOI: http://dx.doi.org/10.18320/JIMD/201502.03204
Journal of International Medicine and Dentistry 2015; 2(3): 204-208
JOURNAL OF INTERNATIONAL MEDICINE AND DENTISTRY To search……………..to know………..…….to share
p-ISSN: 2454-8847
e-ISSN: 2350-045X
Case report
Functional Appliance Therapy: A Case Report
Maimoona Abdul Kader,1 Shahnaz Mahamood,2 Hashim Ali 3
Abstract: Various treatment approaches are available for management of class II malocclusion. Functional jaw orthopaedics in growing individuals can result in a broad beautiful smile, an excellent functional occlusion and noticeably improvement in profile. Following is a case report of a patient with twin block appliance in early permanent dentition period. Significant results can be obtained with proper case selection and patient compliance.
Key words: Class II malocclusion, Functional appliance, Twin block appliance
Introduction:
Functional appliances are those which produce both skeletal and dental changes through force generated by muscles 1. In 1977, functional appliance therapy evolved with the development of twin block appliance by Dr. William Clark, representing significant transition from one piece appliance to twin appliance that promotes normal function 2. The goal of twin block therapy was to produce a technique that could increase the growth response to functional mandibular protrusion by using an appliance system that is simple, comfortable and aesthetically acceptable to patients. 3 The occlusal inclined plane is the fundamental functional mechanism of the natural dentition. Occlusal forces that are transmitted through the dentition provide a constant proprioceptive stimulus to influence the rate of growth and the trabecular structure of the supporting bone.3,4 As Twin blocks are bite-blocks that effectively modify the occlusal inclined plane to induce favourably directed occlusal forces by causing a functional mandibular displacement, they had been chosen as the mode of treatment in the case mentioned.
Case Report:
A 11-year-old pre-adolescent female came to the department with a complaint of forwardly placed upper front teeth. On extra-oral examination, the patient was mesoprosopic facial form with convex facial profile. The nasolabial angle was acute and the chin recessive with incompetent lips with an interlabial gap of 5 mm, and horizontal growth pattern (Image I). The clinical FMA was low. She had positive VTO on advancement of the mandible to edge to edge bite (Image II & III). On functional examination, perioral muscle activity was normal. Incisor exposure on smile was 7mm. On intra-oral examination (Image IV), the patient was in the early permanent dentition, it showed Angle’s class II molar relation, class II canine relation bilaterally, Bellard’s class II Div I incisor relationship and overjet of 9mm, and lower dental midline shifted to right by 2mm with the facial midline (Image V) The overbite was increased to 5 mm (70% Deep bite). The case was diagnosed as Class II skeletal malocclusion with mandibular deficiency and maxillary dental proclination. The lateral cephalometric findings (Image VI) were an increased ANB (5°) with normal SNA
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Journal of International Medicine and Dentistry 2015; 2(3): 204-208
Image I: Pre-treatment photograph
Image II: Pre-treatment profile
Image III: Positive VTO
Image IV: Pre-treatment intra-oral photographs
Image V: Orthopantomogram
Image VI: Comparison of the pre and post-treatment profile
Image VII: Comparison of the pre and post-treatment cephalograms
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angle and SNB and SND was reduced indicating a normal maxilla and retrognathic mandible. The Wits appraisal (+4 mm) confirmed that the patient had a Class II skeletal pattern. The SN-mandibular plane angle and the lower facial proportions were reduced. Lower incisors were normally angulated while the upper incisors were proclined. According to Tanner and White, skeletal maturation Index 5, 6 (Image VII) was G stage which indicated peak pubertal growth spurt. According to MacNamara, most of the class II Div I malocclusion was due to retrognathic mandible where functional appliances are most effective especially during growth period 7. Treatment objective:
1. Reduction of profile convexity and lip incompetence.
2. Achieve skeletal class I by growth modification with functional appliance.
3. Achieve Angle’s class I molar, class 1 Canine and Incisor relation.
Treatment plan: As the patient had skeletal and dental Class II relationship in growing phase (cervical vertebrae maturation indicators , growth modification was planned using functional appliance followed by fixed orthodontic appliance for final detailing of occlusion. Treatment progress: Twin block was fabricated for the patient (Image VIII). To prevent further proclination of lower incisors, acrylic capping was done. After a 10 months
Image IX: post twin block extra-oral photographs
period of wear, there was significant improvement in profile and lip competency (Image VI). Significant correction in molar and the canine relation was obtained along with significant reduction in overjet and overbite (Image IX, X)
Image X: post twin block intra-oral images
Image VIII: Twin block on insertion
Table I: Comparison of pre and post-
treatment parameters
Parameter
Pre-
treatment
Post-
treatment
SNA
SNB
81°
76°
81°
79°
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ANB
SN-GOGN
MX length
Md length
Nasolabial
angle
IMPA
5°
28°
85 mm
105 mm
92°
100°
2°
28°
85 mm
108mm
93°
105°
Discussion:
Skeletal class II malocclusion may be due to maxillary prognathism, mandibular retrognathism or combination of both. Hence, proper understanding of etiology and identifying differential diagnosis is helpful to select treatment planning whether functional, orthodontic or surgical
8. Lower incisor proclination is an important side effect of twin block appliance treatment. In this case, the lower incisor acrylic capping was done to reduce the proclination of lower incisors. Open bite seen immediately after twin block therapy will be only transient and can be settled by the passive eruption of molars or comprehensively by the Phase II therapy. The total duration of phase 1 treatment was 10 months being growth modification using Twin block. 9 Several studies have documented the ability of Twin block to produce significant skeletal and dentoalveolar changes which in combination correct Class II malocclusion.10,11 Here, comparison of pre-treatment and post-treatment lateral cephalogram (Image VII) showed SNA remains unchanged, SNB increased by 3° and there is decrease in ANB angle by 3°. Inclination of maxillary remains same and mandibular incisors were proclined by 5°. Length of the mandible is increased by 3 mm (Table I).
Conclusion:
In the pursuit of ideals in orthodontics, facial balance and harmony are equally important in aesthetic and occlusal
perfection. We cannot afford to ignore the importance of functional jaw orthopaedic technique in achieving these goals by growth guidance during the formative years of facial and dental development. But it should not be expected that all patients who undergo functional appliance therapy will show an increased mandibular growth compared to norms for their age. Some patients grow at a rate less than the norm, while others exceed the normal rate of growth with or without functional appliance therapy.
References:
1. O’Brien K, Wright J, Conboy F, Chadwick S, Connolly I, Cook P, et al. Effectiveness of early orthodontic treatment with the Twin-block appliance: a multicenter, controlled trial. Part 2: Psychosocial effects. Am J Orthod Dentofacial Orthop 2003; 124 (5): 488-95; http://dx.doi.org/10.1016/j.ajodo.2003.06.001 2. Trenouth MJ. A comparison of Twin Block, Andresen and removable appliances in the treatment of Class II Division 1 malocclusion. Funct Orthod 1992; 9 (4): 26-31. 3.Clark WJ. The twin block technique. A functional orthopedic appliance system. Am J Orthod Dentofacial Orthop 1988; 93 (1): 1-18; http://dx.doi.org/10.1016/0889.5406(88)90188-6
4. Clark WJ. The twin block traction technique. Eur J Orthod 1982; 4 (2): 129-38; http://dx.doi.org/10.1093/ejo/4.2.129 5. Hägg U, Taranger J. Maturation indicators and the pubertal growth spurt. Am J Orthod 1982; 82 (4):299-309; http://dx.doi.org/10.1016/0002-9416(82)90464-X 6. Baccetti T, Franchi L, James A, McNamara JA Jr. The cervical vertebral maturation (CVM) method for the assessment of optimal treatment timing in dentofacial orthopedics. Seminars in
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Orthodontics 2005; 11 (3): 119-29; http://dx.doi.org/10.1053/j.sodo.2005.04.005 7. McNamara JA Jr. Rolf Fränkel, 1908-2001 (in memoriam). Am J Orthod Dentofacial Orthop 2002; 121 (2): 238-9; http://dx.doi.org/10.1067/mod.2002.122221 8. Sharma NS. Management of a growing Skeletal Class II patient: A case report. Int J Clin Paediatr Dent 2013; 6 (1):48-54; http://dx.doi.org/10.5005/jp-journals-10005-1187 9. Rabie AB, Al-Kalaly A. Does the degree of advancement during functional appliance therapy matter? Eur J Orthod
2008; 30(3): 274-82; http://dx.doi.org/10.1093/ejo/cjm129 10. Trenouth MJ. Cephalometric evaluation of the Twin-block appliance in the treatment of Class II Division 1 malocclusion with matched normative growth data. Am J Orthod Dentofacial Orthop 2000; 117 (1): 54-9; http://dx.doi.org/10.1016/S0889-5406(00)70248-4 11. Singh GD, Hodge MR. Bimaxillary morphometry of patients with class II division 1 malocclusion treated with twin block appliances. Angle Orthod 2002; 72 (5): 402-9.
************************************************************************* Conflict of interests- Nil Date of submission: 08-12-2015 Source of funding- Nil Date of acceptance: 20-12-2015
Authors details:
1- Corresponding author: Junior Resident, Department of Orthodontics & Dentofacial Orthopaedics, Kannur Dental College, Anjarakandy, Kannur- 670612, Kerala, India; E-mail: [email protected]
2- Junior Resident, Dept. of Orthodontics & Dentofacial Orthopaedics, Kannur Dental College, Anjarakandy, Kannur
3- Professor & Head , Dept. of Orthodontics & Dentofacial Orthopaedics, Kannur Dental College, Anjarakandy, Kannur
