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today Nobel Biocare Global Symposium June 24, 2016

science & research Nobel Biocare Global Symposium 9 The very definition of synergy The whole is greater than the sum of its parts by Dr. Stefan Holst, Germany n Nobel Biocare does not develop individual products but entire solutions that provide fully functional, natural-looking, long-lasting results. In order to ensure long-term clinical performance, safety and cost-efficiency for everyone involved in the treatment process, each Nobel Biocare component has been de- signed to fit and function perfectly with its related components. Together, they produce a finely tuned system. When assessing any implant- supported restorative solution for a patient, one has to keep in mind that the entire system under con- sideration is only as strong as its weakest link. The performance of each specific component depends not only on the quality and design of the component itself but also on its interface with the rest of the restorative system. Consequently, each component should not be eval- uated on its own. Clinically relevant conclusions can only be reached when a component is tested with- in the system it is a part of. Nobel Biocare therefore conducts testing and research on both indi- vidual components, such as im- plants, abutments and screws—and how they work together—as well as the entire system that they consti- tute. We at Nobel Biocare study sys- tems from their initial design to long after delivery to the end-user, the patient. We de- velop and scrutinize engineering and manu- facturing processes, and we carry out quality assurance, clinical research and post-market surveillance. Only with this approach can we be certain that the system will func- tion safely and reliably for many years to come. Parameters that influence long-term performance Computerized simulation tools, such as finite element analysis, and biomechanical testing in the laboratory have served to iden- tify parameters that can impact the perfor- mance of an implant system. These parame- ters include joint compression (the force that acts at the implant–abutment interface un- der loading conditions), preload (the tensile force keeping the components together) and the friction coefficient (which depends on the surface materials that are in contact with each other). Other significant pa- rameters include the force that the patient exerts on the system by chewing (masticatory force), as well as the length of the contact between the abut- ment and the implant, as well as—when using a con- ical connection implant— the angle of the abutment. A small change in any of these parameters—even one not visible to the eye— can lead to extreme load and stress conditions that result in system failure. Precise fit for joint stability The interface between the implant and abutment is critical for joint stabil- ity. Manual adjustment of a cast or the use of a sub- stitute abutment can alter the contact angle and con- tact length. Such an un- defined contact situation entails a degree of risk for the patient that is difficult to predict, much less manage. Furthermore, in vitro force application to an implant-supported prosthesis may additionally exacerbate such misfit. Conse- quently, using an abutment designed and engineered by Nobel Biocare to match the implant is crucial for system performance. It not only affects the fit of the restoration on the implant itself, but may also have an impact on performance-relevant parameters. Preload, the force that holds the components together Preload is defined as the tensile force cre- ated in the clinical screw as the result of screw tightening. It is generated by the appli- cation of torque to the screw, although only a fraction of the torque force is stored as pre- load, while a much larger percentage is spent on overcoming friction. To account for this major loss of torque, and to ensure that the system is sufficiently held together, the screw has to be inserted at the rec- ommended torque. Fully manual screw insertion is likely to result in lower torque and, consequently, suboptimal preload. Insufficient preload leads to in- creased relative motion between the system components, and this can contribute to screw loosening and/ or component failure. Conversely, preload values that are too high can result in component fracture. Optimized to the last detail Nobel Biocare abutments are delivered with a dedicated clinical screw that has been optimized for the implant–abutment system it is a part of. Depending on the abutment, connection type and platform size, screws come with or without a surface coating. The absence or presence of the coating and the coating type all affect the pre- load. For exam- ple, with a diamond-like carbon coating, screws mar- keted under the TorqTite brand show higher preload values compared with screws that have a standard titanium surface. Nobel Biocare provides an appropriate screw type for every implant–abutment connection, ensuring a tight and stable fit for long-term performance. Avoid substitutes, minimize patient risk If substitute components are used, the parameters governing system performance are no longer controlled. Consider maximum joint compression—which defines the load that the implant collar can bear—as an exam- ple: A substitute may result in a force that is higher than the allowed maximum, causing the implant to fracture. To prevent such catastrophic results, the peak forces have to be distributed in a con- trolled way. This can only be achieved by using high-quality, precision-manufactured compo- nents that have been designed and tested both individually and as part of the system for which they have been designed. 7  Precise fit ensures long-term performance. For conical connection implants, joint compression (p) depends on a number of variables, such as preload (tensile force, Fa), friction angle (␣) and contact length (l). Small changes in any of these parameters can lead to extreme load and stress conditions, which can cause implants to fracture.  Dr. Stefan Holst, Vice President of Implant Systems and Research at Nobel Biocare: “Clinically relevant conclusions can only be reached when a component is tested within the system of which it is a part.”  Mismatching components can have severe consequences. Imprecise fit leads to uncontrolled peak forces, which may result in implant fracture. NOTE: Dr. Stefan Holst will be giving a presentation today as part of the main program session, titled “Prosthetic concepts—Reaching op- timal esthetic outcomes with CAD/CAM solutions,” which will run from 1 to 5 p.m.

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