Three-dimensional finite element analysis of the stability of mini-implants close to the roots of adjacent teeth upon application of bite force

Abstract

To investigate the cause of mandibular implant loss, we evaluated the stress distribution in the bone under bite force when the miniimplant was near the root using three-dimensional finite element analysis. Our analysis involved four finite element models with different distances between the implant and adjacent tooth root and three loading conditions. With loading of the tooth only or both the tooth and implant, the peak stress within the bone around the implant neck, displacement, and stress surrounding the bone near the root increased as the distance between the implant and root decreased. However, with separate loading of the implant, the stress did not correlate with the distance between the implant and root. Application of bite force increases stress within bones surrounding mini-implants near the roots of adjacent teeth and may threaten implant stability, but simple orthodontic loading has little effect on the stress distribution at the mini-implant-bone interface.

Can maxilla and mandible bone quality explain differences in orthodontic mini-implant failures?

“…The observed peak displacement values were compatible with previous FE studies designed with similar loading regime and bone-OMI interface representation [14,16,18]. As far as we know, in the literature, there is no critical displacement value reported able to predict an insufficient OMI primary stability condition.…”

“…The Finite-Element (FE) Method is a powerful tool to predict and prevent biomechanical failures during treatment planning, including those associated with OMI use [4,[13][14][15][16][17][18]. Still, the accuracy of the method in predicting clinical outcomes depends on the user's ability to insert the correct inputs and select an output coherent with the failure mechanism of interest for the analysis.…”

Falhas biomecânicas com uso de mini-implante ortodôntico: análise por elementos finitos

“…Há um consenso de que a redução da força intrusiva em dentes periodontalmente comprometidos é essencial para evitar a reabsorção apical externa da raiz. Embora tenha sido sugerido que a redução da força deve ser proporcional à altura da perda óssea [14][15][16][17], a determinação precisa da força ótima permanece incerta.…”

“…Uma correlação direta entre o deslocamento em EF e o TMI clínico não é viável. No entanto, os resultados desse estudo corroboram com os resultados clínicos (100) e experimentais de TMI (101, 102): o deslocamento diminuiu conforme a espessura do osso cortical e o módulo de elasticidade trabecular aumentaram.Os valores de pico de deslocamento observados no presente estudo foram compatíveis com artigos de elementos finitos que utilizaram regime de carga e representação de interface osso-OMI semelhantes(10,12,14). Até onde sabemos, na literatura, não há relato de valor de deslocamento crítico capaz de predizer uma condição de estabilidade primária insuficiente do OMI.…”