The success of dental implants has become more and more predictable since Brånemark first observed what he later called osseointegration, in 1960 [1], meaning the direct structural and functional interlocking of the natural bone and titanium implant surfaces. With implantation becoming a predictable treatment for dental restorations, patients also have become more critical towards the esthetic outcome and the longevity of the restorations. At the same time, clinicians seek for insertion techniques which can reduce the number of surgeries needed from tooth removal to the final restoration.

When in 1975 Professor Schulte and his team at the Eberhard Karls University in Tübingen first introduced the concept of immediate implantation in fresh extraction sockets, it seemed promising at first [2]. However, the use of a full aluminum-oxide ceramic implant (Tübingen implant, Friedrichsfeld, Mannheim, Germany, shown in Fig. 1 on the left side) with small lacunae for bone apposition rather than a screw-shaped profile led to an intolerable rate of early implant failure.

Today, almost 40 years after the introduction of the concept of immediate implantation, there have been a lot of developments regarding insertion technique as well as structural changes of the implants and their surfaces and immediate implantation has become a concept widely accepted and proven successful in many studies [3–5].

This success is often assessed by referring to survival rates. However, a more precise method is the determination of the rate of osseointegration over a long-term period. Many articles, although using radiographic images to assess the bone-level changes, fail to provide the used measurement protocol. An adequate comparison between two or more images can only be achieved by using a constant reference point and reference length as well as a factor to eliminate the distortion factor often present in radiographic images. Further, this is the only way to compare results found by different working groups, or the same group, in different examinations.