International Journal of Experimental Dental Science

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VOLUME 7 , ISSUE 2 ( July-December, 2018 ) > List of Articles


Twin-layered Twin Block

Sujala G Durgekar, Nagaraj Kolur, Harsha Puttaraju

Keywords : Deep anterior bite, Skeletal class II, Trimming, Twin-block appliance

Citation Information : Durgekar SG, Kolur N, Puttaraju H. Twin-layered Twin Block. Int J Experiment Dent Sci 2018; 7 (2):136-138.

DOI: 10.5005/jp-journals-10029-1183

License: CC BY-NC 4.0

Published Online: 01-03-2019

Copyright Statement:  Copyright © 2018; The Author(s).


Background: Twin-block appliance is a widely used myofunctional appliance to correct a skeletal discrepancy in growing class II individuals. In patients with deep anterior bite and horizontal growth pattern, the posterior maxillary block has to be trimmed for the active eruption of lower molars to flatten the curve of spee. The upper block is trimmed 1–2 mm every appointment to encourage lower molar eruption. By keeping the minimal clearance between the lower molar and upper block the tongue is prevented from spreading laterally between the teeth. This might prevent the eruption of mandibular posterior teeth. We have modified the twin block appliance by incorporating two colors alternatively for the maxillary block. This modification acts as a guide for controlled trimming of the upper block. Conclusion: It is a simple and effective way to prevent the development of lateral open bite during the active phase of twin block therapy. Clinical significance: Prevents excessive trimming of the blocks hence reduces the risk of developing posterior open bite due to tongue spreading laterally between the teeth.

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  1. Lund DI, Sandler PJ. The effects of twin Blocks: a prospective controlled study. Am J Orthod Dentofacial Orthop 1998; 113(1): 104-110.
  2. Jamilian A, Show Katbakhsh R, Amiri SS. Treatment effects of the R-appliance and twin block in Class II div 1 malocclusion. Eur J Orthod 2011;33(4):354-358.
  3. Mahamad IK, Neela PK, Mascarenhas R, et al. A comparison of twin block and forsus (FRD) functional appalince- a cephalometric study. Int J Orthod Milwaukee Fall 2012;23(3):49-58
  4. Yaqoob O, Dibiase AT, Fleming PS, et al. Use of the Clark twin block functional appliance with and without an upper labial bow: a randomized controlled trail. Angle Orthod 2012;82(2): 363-369.
  5. Brien KO’, Wright J, Conboy F, et al. Effectiveness of early orthodontic treatment with the twin block appliance: a multicenter, randomized, contolled trial. Part 1: dental and skeletal effects. Am J Orthod Dentofacial Orthop 2003;124(3):234-243
  6. William J Clark. Twin block therapy: Applications in Dentofacial orthopedics. C.V. Mosby (2th edition) 2002;12-15.
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