Mandibular orthopedic advancement in different facial patterns and distinct stages of skeletal maturation

Abstract

The Herbst appliance can be very effective in treatment of Class II patients with mandibular retrognathism. Because of the continuous action in a full-time basis, treatment time using it normally takes from six to ten months, and is usually followed by a second phase of full fixed appliances, in order to obtain both occlusal refinement and long term stability. Despite Herbst appliance’s effectiveness in the occlusal and dentoalveolar perspectives, its facial results may differ among patients with different growth patterns, as well as in distinct stages of skeletal maturation. In the current paper, two patients with different facial patterns are presented, who were treated under the same protocol, using Herbst and full fixed appliances in different skeletal maturation stages, and both dentoalveolar and facial results are compared and discussed.

Alterações dentárias e esqueléticas dos aparelhos propulsores mandibulares fixos

“…O aparelho de Herbst é provavelmente o aparelho funcional mais usado em todo o mundo para corrigir o retrognatismo mandibular e é capaz de tratar com sucesso casos difíceis de má oclusão de Classe II 7,9 , despertando grande interesse na comunidade ortodôntica desde o final da década de 1970, devido ao seu mecanismo de ação contínuo 10 .…”

“…Os principais efeitos do Herbst estão nas regiões dentoalveolares anterior e posterior da maxila 9,12 , provocando retroclinação dos incisivos superiores, distalização e intrusão dos molares superiores e rotação para trás do plano oclusal; os efeitos esqueléticos permanecem controversos 12 . Um dos efeitos colaterais observados após seu uso é a inclinação vestibular dos incisivos inferiores, que se não for controlada, aumenta a probabilidade de recidiva e outros danos 13 .…”

Efficacy of a modified twin block appliance compared with the traditional twin block appliance in children with hyperdivergent mandibular retrognathia: protocol for a single-centre, single-blind, randomised controlled trial

“…Hyperdivergent convex deformity in children, caused by long-term mouth breathing,11 is one of the difficulties in orthodontic treatment 12 13. The current clinical methods for mandibular growth guidance mainly include twin block (TB), activator and Herbst, whose main function is to protrude the mandible and stimulate its growth 14–16. However, the above traditional mandibular advancement devices (MADs) have obvious limitations in the treatment of children with long-face growth patterns 17.…”