Journal of Oral Implantology April 2012 - (Page 133)

RESEARCH Implant-Retained Mandibular BarSupported Overlay Dentures: A Finite Element Stress Analysis of Four Different Bar Heights Mansoor Rismanchian, DDS, MS1 Mansour Dakhilalian, DDS, MS1 Farshad Bajoghli, DMD, MS1 Ehsan Ghasemi, DDS, MS1* Pooyan Sadr-Eshkevari, DDS2 Proper stress distribution on dental implants is necessary in bar-retained implant overlay dentures. We aimed to comparatively assess this stress distribution according to different bar heights using finite element models. A three-dimensional (3D) computer model of mandible with 2 implants (ITI, 4.1 mm diameter and 12 mm length) in canine areas and an overlying implant-supported bar-retained overlay denture were simulated with 0-, 1-, 2-, and 3-mm bar heights using ABAQUS software. A vertical force was applied to the left first molar and gradually increased from 0 to 50 N. The resultant stress distribution was evaluated. Bars of 1 and 2 mm in height transferred the least stress to the implants (3.882 and 3.896 MPa, respectively). The 0-mm height of the bar connection transferred the highest stress value (4.277 MPa). The amount of stress transferred by 3-mm heights of the bar connection was greater than that of 1- and 2-mm bar connections and smaller than that of 0-mm bar connection (4.165 kgN). This 3D finite element analysis study suggested that the use of Dolder bar attachment with 1- and 2-mm heights could be associated with appropriate stress distribution for implant-retained overlay dentures. Key Words: dental implants, dental stress analysis, dentures, finite element analysis, implant-supported dental prostheses, overlay dentures INTRODUCTION Department of Fixed Prosthodontics, Torabinejad Research Center, School of Dental Medicine, Isfahan University of Medical Sciences (MUI), Isfahan, Iran. 2 Dental Section at Farzan Institute of Science, Research and Technology, Tehran, Iran. * Corresponding author, e-mail: swt_f@yahoo.com DOI: 10.1563/AAID-JOI-D-09-00037.1 1 ental implants have been used increasingly to replace missing teeth in partially and completely edentulous patients. The rationale of using dental implants is sometimes to improve retention of the prostheses.1 Though prostheses fully supported by Journal of Oral Implantology 133 D

Table of Contents for the Digital Edition of Journal of Oral Implantology April 2012

Research Letters: A New Editorial Format for the Rapid Disclosure of Innovative Data and Concepts, Didactic Demonstrations, and Scientific Discussions
Effect of Defective Collagen Synthesis on Epithelial Implant Interface: Lathyritic Model in Dogs. An Experimental Preliminary Study
Presence of Aspartate Aminotransferase in Peri-Implant Crevicular Fluid With and Without Mucositis
Deformation of Implant Abutments After Framework Connection Using Strain Gauges
Implant-Retained Mandibular Bar-Supported Overlay Dentures: A Finite Element Stress Analysis of Four Different Bar Heights
The Efficacy of Mylohyoid Nerve Anesthesia in Dental Implant Placement at the Edetulous Posterior Mandibular Ridge
Metal-Ceramic Screw-Retained Implant Fixed Partial Denture With Intraoral Luted Framework to Improve Passive Fit
A Relaxed Implant Bed: Implants Placed After Two Weeks of Osteotomy With Immediate Loading: A One Year Clinical Trial
A Modified Technique for Removing a Failed Abutment Screw From an Implant With a Custom Guide Tube
Therapy for Missing Lower Medial Incisor by Means of Reduced Diameter Implants
Simplifying the Implant Treatment Plan for an Elderly Patient
The Use of Leukocyte- and Platelet-Rich Fibrin During Immediate Postextractive Implantation and Loading for the Esthetic Replacement of a Fractured Maxillary Central Incisor
Atraumatic Removal of an Asymptomatic Migrated Dental Implant Into the Maxillary Sinus: A Case Report
Tooth-Implant Connection: A Review

Journal of Oral Implantology April 2012