Após o estudo elaborado e agora apresentado na presente dissertação, resta apenas tecer algumas considerações.
Não é ainda consensual que a Classe II se deva maioritariamente a retrusão mandibular. Ora, dependendo das referências tidas em conta, diferentes foram as conclusões dos vários estudos que se tiveram em consideração. No entanto, a maioria dos autores tem vindo a observar a retrusão como um importante factor.
Segundo Moss, estímulos ambientais (epigenéticos) não serão independentes do potencial genético intrínseco. Apesar de os estímulos externos se parecerem sobrepor aos estímulos intrínsecos será de esperar uma resposta diferente em diferentes indivíduos (genética). Avaliação do estadio de desenvolvimento por radiografias de mão e punho ou maturação das vertebras cervicais para estabelecimento da proximidade ao pico de crescimento parecem ser um bom indicador para maximizar os efeitos.
A literatura não tem apresentado um sistema uniformiazado para a avaliação do crescimento induzido pelos aparelhos. Além do crescimento sagital, também a posição relativa do mento no perfil facial deveria ser analisada. Rotação posterior da mandíbula associada a alongamento poderá não resultar em alterações clinicamente significativas.
O estabelecimento do estadio de desenvolvimento foi descorado em vários estudos e poucos são os estudos que avaliaram a permanência das alterações a longo prazo.
Tendo em conta estas limitações, foram mais os estudos a suportar a tese de que os aparelhos funcionais potenciam o crescimento mandibular, especialmente quando considerado o pico de crescimento. Não deverá no entanto ser ignorado o “efeito rebound”, que representa uma diminuição dos incrementos sagitais após o tratamento. A estabilidade a longo prazo ficou associada a um tratamento durante o pico de crescimento seguido de um período de aparelho fixo para acerto da oclusão.
As classes II foram corrigidas na grande maioria dos casos, por vezes quase exclusivamente à custa de efeitos dento-alveolares.
Investigações uniformizadas, com avaliação do estadio de desenvolvimento e padrão de crescimento – vertical ou horizontal – assim como estabelecimento de follow- up a longo prazo para aferir manutenção dos resultados após o fim do crescimento parece ser necessário, se não mesmo essencial, para responder cabalmente a esta questão.
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A
ANEXOS
Imagens exemplificativas dos aparelhos funcionais em estudo: Imagem 1
Activador – Retirado de http://www.northstardental.com/lab
-services/functional-therapy/activator-51.html, em 26.06.13
Imagem 2
Bionator- Retirado de http://www.ortodonziabelluno.it/
B Imagem 3
Aparelho de Fränkel II – Retirado de http://www.northstardental
.com/lab-services/functional-therapy/frankel-62.html 250613,
em 26.06.13
Imagem 4
Twin Block- Retirado de http://www.northstardental.com/lab-
C Imagem 5
Aparelho de Herbst Removível – http://www.classoneortho.ca/ remove.html, em 26.06.13