Journal of Oral Implantology October 2012 - (Page 557)

RESEARCH Impact of Dental and Zygomatic Implants on Stress Distribution in Maxillary Defects: A 3-Dimensional Finite Element Analysis Study Fatih Mehmet Korkmaz, DDS, PhD1* Yavuz Tolga Korkmaz, DDS, PhD2 Suat Yalug, DDS, PhD3 ˘ Turan Korkmaz, DDS, PhD3 The aim of this study was to evaluate the stress distribution in the bone around dental and zygomatic implants for 4 different implant-supported obturator prostheses designs in a unilaterally maxillary defect using a 3-dimensional finite element stress analysis. A 3-dimensional finite element model of the human unilateral maxillary defect was constructed. Four different implant-supported obturator prostheses were modeled; model 1 with 2 zygomatic implants and 1 dental implant, model 2 with 2 zygomatic implants and 2 dental implants, model 3 with 2 zygomatic implants and 3 dental implants, and model 4 with 1 zygomatic implant and 3 dental implants. Bar attachments were used as superstructure. A 150-N vertical load was applied in 3 different ways, and von Mises stresses in the cortical bone around implants were evaluated. When the models (model 1–3) were compared in terms of number of implants, all of the models showed similar highest stress values under the first loading condition, and these values were less than under model 4 conditions. The highest stress values of models 1–4 under the first loading condition were 8.56, 8.59, 8.32, and 11.55 Mpa, respectively. The same trend was also observed under the other loading conditions. It may be concluded that the use of a zygomatic implant on the nondefective side decreased the highest stress values, and increasing the number of dental implants between the most distal and most mesial implants on the nondefective side did not decrease the highest stress values. Key Words: dental implant, zygomatic implant, obturator, prosthesis, finite element analysis INTRODUCTION I n dentate maxillary defects, achievement of retention and optimum stability of obturator prosthesis by conventional techniques is very difficult.1–7 The advent of osseointegration and the combination of implants and prosthetic obturators has provided significant benefit, especially in the rehabilitation of edentulous maxillectomy 1 Department of Prosthodontics, Faculty of Dentistry, Karadeniz Technical University, Trabzon, Turkey. 2 Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gazi University, Ankara, Turkey. 3 Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey. * Corresponding author, e-mail: fmkorkmaz@hotmail.com DOI: 10.1563/AAID-JOI-D-10-00111 patients.5 Endosteal implants can enhance patients’ use of the prostheses and can markedly improve the quality of life of edentulous patients after maxillectomy.2 Because a limited amount of maxillary bone remains following maxillectomy, implant placement for anchoring a prosthesis usually involves more remote sites, such as the zygomatic bone.2,4,5 The zygomatic implants were first introduced to dentistry for reconstruction of the atrophic edentulous maxilla1–3,7 and are now being used for establishing retention and support for a maxillary prosthesis after maxillectomy.1,2 Scmidt et al1 found that the combination of zygomatic and standard endosseous implants can be used for retaining and support of maxillary obturator prostheses after extensive resecJournal of Oral Implantology 557

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

Should the Implant Fit the Patient or Should the Patient Fit the Implant?
Histologic and Biomechanical Evaluation of Alumina-Blasted/Acid-Etched and Resorbable Blasting Media Surfaces
Impact of Dental and Zygomatic Implants on Stress Distribution in Maxillary Defects: A 3-Dimensional Finite Element Analysis Study
Precision of Implant Placement With Stereolithographic Templates: A Pilot In Vitro Study
An Evaluation of Biocompatibility of Indigenously Produced Pure Titanium: An Experimental Study in Rabbits
Relationship Between Smoking and Bleeding on Probing
Stress Analysis in Platform-Switching Implants: A 3-Dimensional Finite Element Study
Acrylic Resin Polymerization in Direct Contact to the Abutment and the Temperature at Bone-Implant Interface: A Pilot In Vitro Study
Clinical Application of Stereolithographic Surgical Guide With a Handpiece Guidance Apparatus: A Case Report
Fixed Rehabilitation of Severely Atrophic Jaws Using Immediately Loaded Basal Disk Implants After In Situ Bone Activation
A Functional Open-Tray Impression Technique for Implant-Retained Overdenture Prostheses
Use of Plasma Rich in Growth Factor for Schneiderian Membrane Management During Maxillary Sinus Augmentation Procedure
A Technique to Facilitate the Fabrication of Provisional Restorations for ITI Solid Abutments
Influence of Etiologic Factors in Peri-Implantitis: Literature Review and Case Report
Simplistic Partially Limiting Surgical Guide for Flapless Implant Placement: A Case Report
Types of Implant Surgical Guides in Dentistry: A Review
Rehabilitation of Atrophic Posterior Maxilla With Zygomatic Implants: Review

Journal of Oral Implantology October 2012