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VOLUME 17 , ISSUE 1 ( January, 2016 ) > List of Articles


Dentoskeletal and Soft Tissue Effects in the Treatment of Class II Malocclusion with Klammt's Elastic Open Activator

Sheila Marques Inamassu-Lemes, Acácio Fuziy, André Luiz Ferreira Costa, Paulo Eduardo Guedes Carvalho, Ana Carla Raphaelli Nahás-Scocate

Citation Information : Inamassu-Lemes SM, Fuziy A, Costa AL, Carvalho PE, Nahás-Scocate AC. Dentoskeletal and Soft Tissue Effects in the Treatment of Class II Malocclusion with Klammt's Elastic Open Activator. J Contemp Dent Pract 2016; 17 (1):63-69.

DOI: 10.5005/jp-journals-10024-1804

Published Online: 01-06-2016

Copyright Statement:  Copyright © 2016; The Author(s).



The purpose of this study was to evaluate the dentoskeletal and soft tissue effects resulting from treatment with Klammt's elastic open activator (EOA) functional orthopedic appliance in patients with Class II malocclusion characterized by mandibular deficiency.

Materials and methods

Teleradiographs were evaluated in the lateral aspect of the initial (T1) and final (T2) orthopedic phases for 16 patients with Class II, Division 1 malocclusion. The age range was from 9 to 11.2 years, with a mean age of 9.9 years. The cephalometric points were demarcated, and cephalometric measurements were obtained by the same investigator to avoid interobserver variability.


The EOA promoted increased lower anterior facial height (LAFH), increased effective mandibular length, clockwise rotation of the mandible, retrusion and verticalization of the upper incisors, proclination and protrusion of the lower incisors, extrusion of the upper molars, mesial movement of the lower molars and anterior projection of the lower lip.


Skeletal changes characterized by an increase in mandibular length and dentoalveolar changes with an emphasis on the verticalization and retrusion of the upper incisors, proclination of the lower incisors and mesial positioning of the lower molars were key to improving the occlusal relationship and esthetic facial factors.

Clinical significance

The EOA is well indicated in patients with Class II malocclusion due to mandibular deficiency with increased overbite, proclined upper incisors and verticalized lower incisors.

How to cite this article

Inamassu-Lemes SM, Fuziy A, Costa ALF, Carvalho PEG, Nahás-Scocate ACR. Dentoskeletal and Soft Tissue Effects in the Treatment of Class II Malocclusion with Klammt's Elastic Open Activator. J Contemp Dent Pract 2016;17(1):63-69.

Conflicts of Interest

None declared

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