Mechanics of mechanically fastened joints in polymer–matrix composite structures – A review

T elusive dream of replacing missing teeth with artificial analogs has been part of dentistry for a thousand years. The coincidental discovery by Dr P-I Branemark and his coworkers of the tenacious affinity between living bone and titanium oxides, termed osseointegration, propelled dentistry into a new age of reconstructive dentistry. Initially, the essential tenets for obtaining osseointegration dictated the atraumatic placement of a titanium screw into viable bone and a prolonged undisturbed, submerged healing period. By definition, this required a 2-stage surgical procedure. To comply, a coupling mechanism for implant placement and the eventual attachment of a transmucosal extension for restoration was explored. The initial coronal design selected was a 0.7-mm-tall external hexagon. At its inception, the design made perfect sense, because it permitted engagement of a torque transfer coupling device (fixture mount) during the surgical placement of the implant into threaded bone and the subsequent second-stage connection of the transmucosal extension that, when used in series, could effectively restore an edentulous arch. As 20 years of osseointegration in clinical practice in North America have transpired, much has changed. The efficacy and predictability of osseointegrated implants are no longer issues.1–7 During the initial years, research focused on refinements in surgical techniques and grafting procedures. Eventually, the emphasis shifted to a variety of mechanical and esthetic challenges that remained problematic and unresolved.8–10 During this period, the envelope of implant utilization dramatically expanded from the original complete edentulous application to fixed partial dentures, single-tooth replacement, maxillofacial and a myriad of other applications, limited only by the ingenuity and skill of the clinician.11–13 The external hexagonal design, ad modum Branemark, originally intended as a coupling and rotational torque transfer mechanism, consequently evolved by necessity into a prosthetic indexing and antirotational mechanism.14,15 The expanded utilization of the hexagonal resulted in a number of significant clinical complications.8–11,16–22 To mitigate these problems, the external hexagonal, its transmucosal connections, and their retaining screws have undergone a number of modifications.23 In 1992, English published an overview of the thenavailable external hexagonal implants, numbering 25 different implants, all having the standard Branemark hex configuration.14 The external hex has since been modified and is now available in heights of 0.7, 0.9, 1.0, and 1.2 mm and with flat-to-flat widths of 2.0, 2.4, 2.7, 3.0, 3.3, and 3.4 mm, depending on the implant platform. The available number of hexagonal implants has more than doubled. The abutment-retaining screw has also been modified with respect to material, shank length, number of threads, diameter, length, thread design, and torque application (unpublished data, 1998).23 Entirely new secondand third-generation interface coupling geometries have also been introduced into the implant milieu to overcome intrinsic hexagonal deficiencies.24–28 Concurrent with the evolution of the coupling geometry was the introduction of a variety of new implant body shapes, diameters, thread patterns, and surface topography.26,27,29–36 Today, the clinician is overwhelmed with more than 90 root-form implants to select from in a variety of diameters, lengths, surfaces, platforms, interfaces, and body designs. Virtually every implant company manufactures a hex top, a proprietary interface, or both; “narrow,” “standard,” and “wide” diameter implant bodies; machined, textured, and hydroxyapatite (HA) and titanium plasma-spray (TPS) surface implants; and a variety of lengths and body shapes (Table 1). In the wide-diameter arena alone, there are 25 different offerings, 15 external hexagonal, and 10 other interfaces available in a number of configurations. 1Adjunct Professor of Prosthodontics, Graduate Prosthodontics, Indiana University, Indianapolis, Indiana; Assistant Research Scientist, Department of Restorative Dentistry, University of California at San Francisco; and Private Practice, Roseville, California.

/pdf/implants-and-components-entering-the-new-millennium-3eig9xnt5y.pdf

Implants and components: entering the new millennium.

Uncertainties and dynamic problems of bolted joints and other fasteners

https://www.fml.t.u-tokyo.ac.jp/~izumi/Bolt/WG/fem_bolted_joints_modelling_Korea.pdf

Finite element analysis and modeling of structure with bolted joints

The significance of tightening abutment screws and gold cylinders to osseointegrated fixtures with the correct torque is demonstrated, and a simple relationship between applied torque and screw preload is derived by use of mechanical engineering principles. The principles of a number of tightening methods are outlined and assessments made of their accuracy. The difference between optimum and design torque is highlighted. The necessity and means of achieving optimum torque to ensure a reliable joint in clinical practice is discussed.

Tightening characteristics for screwed joints in osseointegrated dental implants

Part 1 Introduction to the bolted joint: basic concepts stress and strength considerations threads and their strength materials stiffness and strain considerations. Part 2 Tightening the joint (establishing the clamping force): introduction to assembly torque control of bolt preload torque and turn control stretch control preload control ultrasonic measurement of bolt stretch or tension. Part 3 The joint in service: theoretical behaviour of the joint under tensile loads behaviour of the joint loaded in tension - a closer look in-service behaviour of a shear joint joint failure self loosening fatigue failure corrosion gasketed joints and leaks. Part 4 Using the information: selecting preload for an existing joint design of joints loaded in tension the design of gasketed joints the design of joints loaded in shear.

An introduction to the design and behavior of bolted joints

MATERIAL PROPERTIES AND SELECTION Fastener Materials, A.C. Hood Joining with Aluminum Alloy Bolts and Nuts, R.E. Mack Thread Lubricants, G. Novak and T. Patel Adhesives and Sealants for Bolting, J. Cocco PROCESSING OF FASTENERS Fastener Manufacturing, J.A. Phebu and P.K. Kasp Fastener Coatings, J. Laurillard Fastener Quality, C.B. Wackrow THREADED FASTENERS Screw Threads, E. Schwartz and J.H. Bickford Fasteners Head Markings, C. Wilson Computing the Strength of a Fastener, J. Barron Computing the Stiffness of a Fastener, J. Barron Metric Fasteners, B. Marbacher Washers: A Guide to Their Function and Selection, M. Levinson Belleville Springs, G. Davet Vibration-Resistant Fasteners, J.R. Dudley Concrete Anchors, R.L. Zink Aerospace Bolts, S. Sadri DESIGN AND ANALYSIS OF BOLTED JOINTS VDI Joint Design Procedures, A.W. Heston Design of Gasketed Joints, B.S. Nau ASME Boiler and Pressure Vessel Code Design Rules for Bolted Flanges, G. Bibel Design of Joints Loaded in Shear, R.T. Barrett Design Rules for Structural Steel Bolting, J.H. Bickford and W.A. Milek ASSEMBLY OF BOLTED JOINTS Behavior of a Bolted Joint During Assembly, J.H. Bickford Tightening Groups of Fasteners in a Structure and the Resulting Elastic Interaction, G. Bibel Hydraulically Powered Wrenches, G. Sturdevant Hydraulic Stud Tensioning, W. Biach The Multi-Jackbolt Tensioning System, R.H. Steinbock Selecting Fastening Strategies and Equipment for Mass Production, J.R. Bippus Torque Control of Assembly, J.H. Bickford Stretch Control, R. Corbett Increasing Joint Performance by Tightening Bolts to Yield, P.W. Wallace Torque-Angle-Tension Control, R.S. Shoberg Control with Direct Tension Indicators, D. Sharp Use of Ultrasonics in Bolted Joints, S. Nassar Selecting Preload for an Existing Joint, J. H. Bickford THE JOINT IN SERVICE Joint Diagrams, J.H. Bickford Bolt Fatigue, F.R. Kull Corrosion, K.E. Yee The Susceptibility of Fasteners to Hydrogen Embrittlement and Stress Corrosion Cracking, L. Raymond Vibration-and Shock-Induced Loosening, D. Hess TESTING AND INSPECTION OF BOLTS AND JOINTS Statistical Design and Analysis of Multivariable Experiments, B. Clement Field Testing of Structural Bolts and Installation Tools Using a Bolt Tension Calibrator, J. Wilhelm Torque-Tension Audits, R. Shoberg EDUCATION AND TRAINING Fastening Technology Education, B. Blendu

Handbook of bolts and bolted joints

GASKETS Gasket Behavior and Its Influence on the Safety of Flanged Joints, J. Latte Internal Combustion Engine Gaskets, D.E. Czernik Industrial Gaskets, J. Latte and D. Coomber Chemical Gaskets, J. Cocco EVALUATING AND TESTING GASKETS PVRC/MTI Technology for Characterizing Gaskets Used in Bolted Flanged Connections, M. Derenne, J.R. Payne, L. Marchand, and A. Bazergui SELECTING A GASKET Gasket Selection-A Flowchart Approach, J.R. Winter Reliable Gasket Calculations on a Personal Computer, R. Rodel THE DESIGN OF GASKETED JOINTS Introduction to the Design of Gasketed Joints, J.H. Bickford ASME Flanged Joint Design Rules-New vs. Traditional, J.R. Payne and R.W. Schneider Bolted Flanged Connections for Noncircular Pressure Vessels, A.E. Blach Bolted Flanged Connections for Full-Face Gaskets, A.E. Blach THE GASKETED JOINT IN SERVICE Assembling a Gasketed Joint, J.H. Bickford In-Service Inspection of Gasketed Joints, J.H. Bickford Stopping Leakage of In-Service Joints, P. Kearns

John H. Bickford

Papers

An introduction to the design and behavior of bolted joints

Handbook of bolts and bolted joints

Gaskets and Gasketed Joints

Fortune and Men's Eyes

Selecting Preload for an Existing Joint