Biomechanical behavior of a mandibular class I removable partial denture distally supported by an osseointegrated implant: tridimensional analysis by finite element analysis

Abstract

The osseointegrated implants have been associated with the removable partial denture (RPD) to improve the support and retention of the RPD diminishing the demand on the support structures. However, the data about the benefits of the implant for diminishing the stress on the dental support and how the stress is distributed at the bone/implant interface based on finite element analysis (FEA) is not clear yet. The purpose of the present study is to evaluate through a tridimensional (3-D) FEA the stress distribution and displacements of the support structures of a RPD distally supported by an osseointegrated implant. Three mathematical models (M) will be built using a tomography image from a patient with a mandibular Kennedy Class I arch as a template. The patient should have the natural teeth 34 to 44. The M1 will represent a mandibular arch without RPD. The M2 will have a RPD to replace the teeth 35, 36 and 37; and the M3 will have an osseointegrated implant (10 x 3.75 mm) on the 2nd mandibular molar area to support the RPD. The mandibular bone profile and the reminiscent natural teeth will be elaborated using the software Mimics with the tomography images as the reference. The metal cast of the RPD, the acrylic resin teeth and base, the fibromucosa and the implant will be elaborated into the SolidWorks. A box around the implant (10x10x20cm) will be used for the non-linear analysis considering the orthotropic behavior of the bone. The linear and non-linear analysis will be performed using the program Abaqus. The distributed loading (L) will be performed in two ways: L1 - vertical loading (50N) simultaneously applied on each cusp; L2 - oblique (45º) loading (50N) simultaneously on each cusp; and L3 - vertical loading 250N applied only on the tooth 37. The principal stress and the displacement of the abutment teeth, the bone and the bone/implant interface will be obtained to analyze the results under a descriptive statistical analysis. (AU)