Article

Comparative Finite Element Analysis of the Biomechanical Stability of 2.0 Fixation Plates in Atrophic Mandibular Fractures

Postgraduate Student, PhD Program in Oral and Maxillofacial Surgery, University of Pernambuco, Recife, PE, Brazil. Electronic address: .
Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons (Impact Factor: 1.58). 02/2013; 71(2):335-42. DOI: 10.1016/j.joms.2012.09.019
Source: PubMed

ABSTRACT The objective of the present study was to conduct a computational, laboratory-based comparison of the biomechanical stability of 2.0 fixation locking plates with different profiles in Class III atrophic mandibular fractures using 3-dimensional finite element analysis.
Three-dimensional finite element models simulating Class III atrophic mandibular fractures were constructed. The models were divided into 4 groups according to plate thickness (1.0, 1.5, 2.0, and 2.5 mm). Fractures were simulated in left mandibular bodies, and 3 locking screws were used on each side of each fracture for fixation. Bite forces of approximately 63 N were simulated in the incisor and molar regions of the mandibles in finite element models.
The level of compressive strain on the bone around the screw was within the physiological limit. No significant difference was observed in the displacement of bone segments in the fracture region. Von Mises stress was higher during simulated bites in the molar region for plates with thicknesses of 1.0 mm. Plate tension values were below the level required for permanent deformation or fracture in all models. The 2.5-mm-thick plate presented better biomechanical performance than all other plates. The 2.0-mm-thick plate also showed satisfactory results and adequate safety limits.
Large-profile (2.0-mm-thick) locking plates showed better biomechanical performance than did 1.0- and 1.5-mm-thick plates and can be considered an alternative reconstruction plate for the treatment of Class III atrophic mandibular fractures.

1 Bookmark
 · 
110 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The surgical treatment of mandibular condyle fractures currently offers several possibilities for stable internal fixation. In this study, a finite element model evaluation was performed of three different methods for osteosynthesis of low subcondylar fractures: (1) two four-hole straight plates, (2) one seven-hole lambda plate, and (3) one four-hole trapezoidal plate. The finite element model evaluation considered a load applied to the first molar on the contralateral side to the fracture. Results showed that, although the three methods are capable of withstanding functional loading, the lambda plate displayed a more homogeneous stress distribution for both osteosynthesis material and bone and may be a better method when single-plate fixation is the option.
    International Journal of Oral and Maxillofacial Surgery 08/2014; 43(10). DOI:10.1016/j.ijom.2014.07.011 · 1.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: As fractures of the supraorbital region are far less common than midfacial or orbital fractures, a study was initiated to investigate whether fist blows could lead to fractures similar to those often seen in the midface. A detailed skull model and an impactor resembling a fist were created and a fist blow to the supraorbital region was simulated. A transient finite element analysis was carried out to calculate von Mises stresses, peak force, and impact time. Within the contact zone of skull and impactor critical stress values could be seen which lay at the lower yield border for potential fractures. A second much lower stress zone was depicted in the anterior-medial orbital roof. In this simulation a fist punch, which could generate distinct fractures in the midface and naso-ethmoid-orbital region, would only reach the limits of a small fracture in the supraorbital region. The reason is seen in the strong bony architecture. Much higher forces are needed to create severe trauma in the upper face which is supported by clinical findings. Finite element analysis is the method of choice to investigate the impact of trauma on the human skeleton.
    Head & Face Medicine 04/2014; 10(1):13. DOI:10.1186/1746-160X-10-13 · 0.87 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • [Show abstract] [Hide abstract]
    ABSTRACT: This work aimed to compare the stress distribution and mechanical properties of our bridge combined fixation system and commonly used metal locking plate screw system by finite element analysis and by using the Zwick/Z100 testing machine. In addition, we also investigated the clinical outcome of our bridge combined fixation system for femoral fractures in 59 patients from June 2005 to January 2013. As a result, the stress distribution in the bone plate and screws of metal locking plate screw system during walking and climbing stairs was significantly lower than that of metal locking plate screw system. No significant difference in the displacement was observed between two systems. The equivalent bending stiffness of bridge combined fixation system was significantly lower than that of metal locking plate screw system. There were no significant differences in the bending strength, yield load, and maximum force between two systems. All the cases were followed up for 12-24 months (average 18 months). The X-ray showed bone callus was formed in most patients after 3 months, and the fracture line was faint and disappeared at 6-9 months postoperatively. No serious complications, such as implant breakage and wound infection, occurred postoperatively. According to self-developed standard for bone healing, clinical outcomes were rated as excellent or good in 55 out of 59 patients (success rate: 93.2%). Therefore, our findings suggest that our bridge combined fixation system may be a promising approach for treatment of long-bone fractures.
    Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine 09/2014; 228(9). DOI:10.1177/0954411914548866 · 1.14 Impact Factor