Biomechanical effects of rapid maxillary expansion on the craniofacial skeleton, studied by the finite element method

Download
1998-08-01
Iseri, H
Tekkaya, AE
Oztan, O
Bilgic, S
The aim of this study was to evaluate the biomechanical effect of rapid maxillary expansion (RME) on the craniofacial complex by using a three-dimensional finite element model (FEM) of the craniofacial skeleton. The construction of the three-dimensional FEM was based on computer tomography (CT) scans of the skull of a 12-year-old male subject. The CT pictures were digitized and converted to the finite element model by means of a procedure developed for the present study. The final mesh consisted of 2270 thick shell elements with 2120 nodes. The mechanical response in terms of displacement and von Mises stresses was determined by expanding the maxilla up to 5 mm on both sides. Viewed occlusally, the two halves of the maxilla were separated almost in a parallel manner during 1-, 3-, and 5-mm expansions. The greatest widening was observed in the dento-alveolar areas, and gradually decreased through the superior structures. The width of the nasal cavity at the floor of the nose increased markedly. However, the postero-superior part of the nasal cavity was moved slightly medially. No displacement was observed in the parietal, frontal and occipital bones. High stress levels were observed in the canine and molar regions of the maxilla, lateral wall of the inferior nasal cavity, zygomatic and nasal bones, with the highest stress concentration at the pterygoid plates of the sphenoid bone in the region close to the cranial base.
EUROPEAN JOURNAL OF ORTHODONTICS

Suggestions

Micromechanical modeling of semicrystalline polymers with spherulite morphology
Oktay, Hasan Emre; Göktepe, Serdar; Gürses, Ercan; Department of Civil Engineering (2020-10-23)
In this study, a micromechanical constitutive model for semicrystalline polymers is developed. The proposed model considers interactions among the adjacent regions at the same length scale. The neighborhood information is obtained from the well characterized spherulite morphology of polyethylene. Deformation characteristics of a disk-like spherulite model that has similarities with the considered modeling approach are studied using the finite element method. The model discretizes a disklike spherulite i...
The drum spring (DS) retractor: A constant and continuous force for canine retraction
Darendeliler, MA; Darendeliler, Haluk; Uner, O (Oxford University Press (OUP), 1997-04-01)
Although much research has been undertaken on the rate of tooth movement, with different hypotheses having been put forward, the concepts of threshold, light, heavy and optimal forces are not still clear.
The effects of positive core self and external evaluations on performance appraisals
Güven, Lale; Sümer, Canan H; Department of Industrial and Organizational Psychology (2007)
The purpose of this study was to investigate the effects of core self-evaluations (CSEs) and core external-evaluations (CEEs) on performance evaluations. It was hypothesized that people with higher levels of CSEs and CEEs would be more lenient in their performance ratings, when rating neutral performance. The second hypothesis of the study was that people with higher and lower CSEs would engage more in halo when rating neutral performance compared to people with average levels of CSEs. It was further hypoth...
Context-Based Lessons with 5E Model to Promote Conceptual Understanding of Chemical Reactions and Energy Concepts
Cigdemoglu, Ceyhan; Geban, Ömer (2015-01-01)
This study explores whether the context-based approach with 5E model (CBA-5E) can lead to better understanding of chemical reactions and energy concepts when compared to conventional instruction (CI). Additionally, the study delves into the effect of treatment with regards to gender. Eleventh grade science-major classes with 175 students from two public high schools were enrolled. The experimental groups were treated with CBA-5E, the control groups as CI, the treatments were randomly assigned to the groups....
Bioactive Surface Design Based on Functional Composite Electrospun Nanofibers for Biomolecule Immobilization and Biosensor Applications
Uzun, Sema Demirci; Kayaci, Fatma; UYAR, Tamer; TİMUR, SUNA; Toppare, Levent Kamil (2014-04-09)
The combination of nanomaterials and conducting polymers attracted remarkable attention for development of new immobilization matrices for enzymes. Hereby, an efficient surface design was investigated by modifying the graphite rod electrode surfaces with one-step electrospun nylon 6,6 nanofibers or 4% (w/w) multiwalled carbon nanotubes (MWCNTs) incorporating nylon 6,6 nanofibers (nylon 6,6/4MWCNT). High-resolution transmission electron microscopy study confirmed the successful incorporation of the MWCNTs in...
Citation Formats
H. Iseri, A. Tekkaya, O. Oztan, and S. Bilgic, “Biomechanical effects of rapid maxillary expansion on the craniofacial skeleton, studied by the finite element method,” EUROPEAN JOURNAL OF ORTHODONTICS, pp. 347–356, 1998, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67582.