Journal of Oral Implantology August 2013 - (Page 417)

RESEARCH Marginal Fit of Implant-Supported All-Ceramic Zirconia Frameworks Hanaa Hassan Zaghloul, PhD1* Jihan Farouk Younis, PhD2 This study evaluated the effect of fabrication techniques and cyclic loading on the vertical marginal fit of implantsupported fixed partial denture (FPD) frameworks. Thirty implant-supported 3-unit FPD frameworks were fabricated on a model system, divided into 3 equal groups (n ¼ 10). The first group (control) was constructed from base metal alloy; the other 2 test groups were constructed from all-ceramic zirconia using a computer-aided design/computer-aided manufacturing (CAD/CAM) Cerec 3 system and a copy milling (Zirkonzahn) system. A cyclic load of 200 N was applied to each framework for up to 50,000 cycles. Linear measurements were made in micrometers of the vertical gap between the framework and the implant-supported abutment at 16 predetermined points before and after cyclic loading. The frameworks were viewed using scanning electron microscopy to inspect any fractographic features. One-way analysis of variance was performed to compare the marginal discrepancy values of the control and the 2 test groups and for each group; a t test was applied to determine whether significant changes in the fit were observed after cyclic loading (a ¼ 0.05). The CAD/CAM group showed significantly higher marginal gap mean values (80.58 lm) than the Zirkonzahn and control groups (50.33 lm and 42.27 lm, respectively) with no significant difference. After cyclic loading, the CAD/CAM group recorded the highest marginal gap mean value (91.50 6 4.260 lm) followed by control group (72.00 6 2.795 lm); the Zirkonzahn group recorded the lowest marginal gap (65.37 6 6.138 lm). Cyclic loading significantly increased the marginal gap mean values in the control group only. A marginal chip was observed in one of the CAD/CAM ceramic frameworks. Within the limitations of this study, the fabrication technique influenced the marginal fit of the implant-supported 3-unit FPD frameworks. Cyclic loading failed to change the fit of all-ceramic zirconia frameworks, whereas significant changes were found in the metal frameworks. Key Words: implant-supported restoration, marginal fit, ceramic, zirconia, fabrication technique, cyclic loading, fractography INTRODUCTION T he continuous development of osseointegration and implantology makes it possible today to perform prosthetic restorations that provide for the reestablishment of function, esthetics, and phonetics in a foreseeable manner. Thus, the use of dental implants to replace absent teeth has 1 Conservative Dentistry Department, Faculty of Oral and Dental Medicine, Misr International University, Cairo, Egypt. 2 Crown and Bridge Department, Faculty of Dentistry, Ain-Shams University, Heliopolis, Egypt. * Corresponding author, email: DOI: 10.1563/AAID-JOI-D-11-00103 become routine in oral rehabilitation because it prevents the wearing of entire teeth and lateral loads on tooth abutments of removable partial with distal extension.1. To ensure this predictability of treatment, the seating of the prosthesis with total passivity to implants or temporary abutments is very important. Therefore, a passive fit of the fixed partial denture (FPD) is desirable to prevent uncontrolled stresses not only in the adjacent bone but also in the reconstruction itself.2 On the other hand, laboratory studies suggest that most complications with implant-supported prostheses can be directly connected to the lack of passive fit between the prosthetic framework and abutment,3–5 such as Journal of Oral Implantology 417

Table of Contents for the Digital Edition of Journal of Oral Implantology August 2013

Literary Responsibility—Everyone Has a Role to Play
Rehabilitation of Surgically Relocated Integrated Dental Implants With and Without Bone Morphogenesis Protein-2
Marginal Fit of Implant-Supported All-Ceramic Zirconia Frameworks
Influence of the Implant Diameter With Different Sizes of Hexagon: Analysis by 3-Dimensional Finite Element Method
Autologous Dental Pulp Stem Cells in Regeneration of Defect Created in Canine Periodontal Tissue
Histologic and Biomechanical Evaluation of 2 Resorbable-Blasting Media Implant Surfaces at Early Implantation Times
Efficacy of Guided Bone Regeneration Using Composite Bone Graft and Resorbable Collagen Membrane in Seibert’s Class I Ridge Defects: Radiological Evaluation
Minimal Iliac Bone Harvesting in Sinus Lift Surgery
Functional Load in Oblique Bicortical Implants: Parasinusal Implants and Palatine Implants
Ultrasonic Oscillations for Conservative Retrieval of a Rare Fracture of Implant Healing Abutment
Craniofacial Implant-Retained Auricular Prosthesis: A Case Report
Gingival Conditioning in an Implant-Supported Prosthesis: A Clinical Report
An Early Loaded Implant-Supported Mandibular Complete Arch Fixed Prosthesis in a Young Completely Edentulous Patient: A Case Report
Computer Guided Surgery for Implant Placement and Dental Rehabilitation in a Patient Undergoing Sub-Total Mandibulectomy and Microvascular Free Flap Reconstruction
Guided Bone Regeneration for Socket Preservation in Molar Extraction Sites: Histomorphometric and 3D Computerized Tomography Analysis
Osseointegration of Dental Implants and Osteonecrosis of the Jaw in Patients Treated With Bisphosphonate Therapy: A Systematic Review
Review of Current Literature

Journal of Oral Implantology August 2013