De acordo com os achados desta pesquisa, pode-se afirmar que:
• Após seis meses de uso clínico, as molas helicoidais fechadas de níquel-titânio
apresentaram diminuições significantes nas suas taxas de SE e nas FP.
• As molas helicoidais fechadas de níquel-titânio após terem sido mantidas
ativas in vitro por cinco meses, com simulação do movimento dentário, não apresentaram diminuições significantes nas suas taxas de SE, porém as FP apresentaram reduções significativas.
• Laboratorialmente, as diminuições nas FP foram maiores nos dois primeiros
meses e depois se estabilizaram, e as taxas de SE não apresentaram diferenças nos dois meses iniciais, aumentando nos seguintes.
• Apesar dos resultados do artigo in vitro apresentarem divergência no efeito da taxa de SE ao longo do tempo em relação ao artigo in vivo, as molas não foram utilizadas clinicamente e a simulação laboratorial pode não representar com exatidão o que acontece na cavidade bucal.
• Molas helicoidais fechadas de níquel-titânio após o uso clínico perdem a sua
• Portanto, a utilização a longo prazo ou a reutilização de uma mola helicoidal
fechada de níquel-titânio seria desaconselhada, pois está associada a uma diminuição na sua taxa de superelasticidade, na força média do platô clínico superelástico e na sua capacidade de recuperação elástica, o que pode representar complicações na mecânica envolvida. Os clínicos devem compreender as limitações destes materiais decorrentes do tempo de uso, modificando suas expectativas e/ou monitorando a evolução do tratamento.
• Novas pesquisas são necessárias para identificar quais as mudanças que
ocorrem nas temperaturas de transição de ligas de níquel-titânio na cavidade bucal e para determinar qual porcentagem da deformação é causada por deformação martensítica reversível ou por deformação residual permanente com o uso.
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