Journal of Oral Implantology June 2013 - (Page 326)

RESEARCH Regular and Switching Platform: Bone Stress Analysis With Varying Implant Diameter Luis Carlos Merson Vargas, DDS1 Erika Oliveira de Almeida, DDS, MS, PhD2* Eduardo Passos Rocha, DDS, MS, PhD2 Sidney Kina, DDS, MS1 Rodolfo Bruniera Anchieta, DDS, MS2 ´ ´ Amılcar Chagas Freitas Junior, DDS, MS, PhD2 Fabiana Mantovani Gomes Franca, DDS, MS, PhD1 ¸ The aim of this study was to evaluate stress distribution of the peri-implant bone by simulating the biomechanical influence of implants with different diameters of regular or platform switched connections by means of 3-dimensional finite element analysis. Five mathematical models of an implant-supported central incisor were created by varying the diameter (5.5 and 4.5 mm, internal hexagon) and abutment platform (regular and platform switched). For the cortical bone, the highest stress values (rmax and rvm) were observed in situation R1, followed by situations S1, R2, S3, and S2. For the trabecular bone, the highest stress values (rmax) were observed in situation S3, followed by situations R1, S1, R2, and S2. The influence of platform switching was more evident for cortical bone than for trabecular bone and was mainly seen in large platform diameter reduction. Key Words: implant dentistry, finite analysis, bone, stress, loading INTRODUCTION E arly peri-implant bone loss has been observed in many implant systems and through use of different surgical techniques, commonly in the first year of the implant in function and potentially compromising the esthetics of restorations.1–4 A possible cause of this bone loss may be excessive occlusal force and the mechanical properties of the implant, such as its interaction with the bony structure.3,5–8 The implant geometry and type of implant/ abutment connection are important factors for maintaining osseointegration because they influence force transmission to the bone.9 For this reason, clinical situations that improve stress 1 ˜ ˜ Sao Leopoldo Mandic School, Campinas, Sao Paulo, Brazil. Campinas School of Dentistry, UNESP – Univ. Estadual Paulista, ˜ Campinas, Sao Paulo, Brazil. * Corresponding author, e-mail: DOI: 10.1563/AAID-JOI-D-10-00157 2 326 Vol. XXXIX /No. Three / 2013 distribution in bone are increasingly sought to minimize peri-implant bone loss. The term ‘‘platform switching’’ refers to the use of an abutment with a reduced diameter in relation to the diameter of the implant platform, leading to the creation of a horizontal gap at the abutment/ implant junction.10 Based on this principle, the abutment/implant junction is moved medially, so that it is further from the peri-implant bone, which may minimize the impact of the inflammatory cell infiltrate.11,12 Many clinical, histologic, and laboratory studies have suggested that this procedure appears to reduce crestal bone resorption.8,13–15 However, there is still no conclusion as to which abutment and implant diameters best favor stress distribution in the bone when platform switching is used. Therefore, the aim of this study was to evaluate the stress distribution in the peri-implant bone by simulating the influence of different implant diameters with regular and platform-switched connec-

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

Congratulations to Duke Heller, DDS, MS—Pioneer, Teacher, and Mentor
In Vitro Analysis of Resistance to Cyclic Load and Preload Distribution of Two Implant/ Abutment Screwed Connections
Mandibular Implant-Supported Overdenture: An In Vitro Comparison of Ball, Bar, and Magnetic Attachments
An Exploratory Study on Assessment of Gingival Biotype and Crown Dimensions as Predictors for Implant Esthetics Comparing Caucasian and Indian Subjects
A New Approach to the All-on-Four Treatment Concept Using Narrow Platform NobelActive Implants
Regular and Switching Platform: Bone Stress Analysis With Varying Implant Diameter
Comparison Between Immediate and Delayed Laser-Treated Implants Surface With Switching Platform: A Clinical Retrospective Study
Effect of a Multiporous Beta–Tricalicum Phosphate on Bone Density Around Dental Implants Inserted Into Fresh Extraction Sockets
The Effect of Varying Implant Position in Immediately Loaded Implant-Supported Mandibular Overdentures
Bone Regeneration Around Immediate Implants Utilizing a Dense Polytetrafluoroethylene Membrane Without Primary Closure: A Report of 3 Cases
Socket Preservation and Sinus Augmentation Using a Medical Grade Calcium Sulfate Hemihydrate and Mineralized Irradiated Cancellous Bone Allograft Composite
Implant Placement and Immediate Loading With Fixed Restorations in Augmented Sockets. Five-Year Results. A Case Report
Immediate Placement and Provisionalization With Buccal Plate Preservation: A Case Report of a New Technique
Clinical Importance of Recipient Site Characteristics for Vertical Ridge Augmentation: A Systematic Review of Literature and Proposal of a Classification
Postextraction Implant in Sites With Endodontic Infection as an Alternative to Endodontic Retreatment: A Review of Literature
Letter to the Editor

Journal of Oral Implantology June 2013