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Biocompatible materials such as porous bioactive calcium phosphate ceramics or titanium are regularly applied in dental
surgery: ceramics are used to support the local bone regeneration in a given defect, afterwards titanium implants replace
lost teeth. The current gold standard for bone reconstruction in implant dentistry is the use of autogenous bone grafts.
But the concept of guided bone regeneration (GBR) has become a predictable and well documented surgical approach
using biomaterials (bioactive calcium phosphate ceramics) which qualify as bone substitutes for this kind of application
as well. We applied high resolution synchrotron microtomography and subsequent 3d image analysis in order to
investigate bone formation and degradation of the bone substitute material in a three-dimensional manner, extending the
knowledge beyond the limits of classical histology. Following the bone regeneration, titanium-based implants to replace
lost teeth call for high mechanical precision, especially when two-piece concepts are used in order to guaranty leak
tightness. Here, synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial
resolution in combination with high contrast even when exploiting micro-sized features in these kind of highly
attenuating objects. Therefore, we could study micro-gap formation at interfaces in two-piece dental implants with the
specimen under different mechanical load. We could prove the existence of micro-gaps for implants with conical
connections as well as to study the micromechanical behavior of the mating zone of conical implants during loading. The
micro-gap is a potential issue of failure, i. e. bacterial leakage which can induce an inflammatory process.
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