Long term evaluation of osseointegrated implants placed at the same time as a procedure to augment vertical bone height. A retrospective study involving 123 implants over a period of 1 to 5 years

Aim of the study

This was a retrospective study of 123 implants undertaken 1 to 5 years after they were brought into function. The implants were placed at the same time as a procedure to augment vertical bone height.

Materials and methods

At the time of surgery, 123 Brånemark^®, implants required the use of a procedure to augment the vertical bone height because 2 to 7 mm of threads remained exposed. In some cases a titanium reinforced teflon membrane was used to protect the blood clot (group A, 6 patients), others received an allograft (group B, 11 patients) and the remainder, an autograft (group C, 32 patients). They were assessed annually according to a previously described protocol (Buser et al., 1990; 1991).

Results

All the implants except one appeared to be clinically stable at the time of exposure and the clinical success was confirmed by radiographic evaluation demonstrating vertical bone augmentation of 1.35 to 1.9 mm. After 1 year, only 2 implants showed bone loss of approximately 4 mm !

Conclusion

Under the conditions of this retrospective study, it is possible to conclude that vertical bone augmentation can be reliably achieved.

Commentaries

This is a welcome clinical study. Although the groups were not well balanced for statistical purposes, the study does have the merit of confirming the clinical reports that have already appeared on this theme. Time-saving, reliable, tested procedures but perhaps the techniques require favourable tissue conditions and a particularly experienced operator, such as those excellent clinicians who contributed to this work. These results did not occur by chance !