Damping factor for monitoring the bone interface at dental implants

Veltri, Mario
Balleri, Piero
Ferrari, Marco

Mario Veltri, Department of Dental Materials, University of Siena, Siena, Italy Piero Balleri, Department of Oral Surgery and Implantology, University of Siena, Siena, Italy Marco Ferrari, Department of Restorative Dentistry and Dental Materials, University of Siena, Siena, Italy

Correspondence to:Dr Mario Veltri Department of Dental Materials University of Siena V.le Bracci Siena 53100 Italy; Tel.: +39 0577 233131; Fax: +39 0577 233117; e-mail: [email protected]

To cite this article: Veltri M, Balleri P, Ferrari M. Damping factor for monitoring the bone interface at dental implants.

Date: Accepted 4 November 2006

Clinical Oral Implants Research 18(6):p 738-742, December 2007.

Objectives

The aim of this study is to investigate whether the damping of osseointegrated implants, as measured quantitatively with the Osstell^™ equipment, is related to the fractal dimension of peri-implant bone.

Material and methods

Fifty-five maxillary implants in function for 3 years before the present study were investigated. Two Osstell^™ measurements were obtained for each implant with the transducer oriented first palatally and then distally. Using the half-power bandwidth method, the damping was calculated from the frequency/amplitude plot obtained from the Osstell^™. Damping data were then related to the fractal dimension of peri-implant bone. Fractal dimensions were calculated using a box-counting algorithm on digitally processed intra-oral radiographs of the implants. A Spearman's test was used to verify the correlation between damping and fractal dimension values.

Results

All the implants were clinically stable and free from symptoms. The mean ISQ was 63 for the palatal orientation and 71 for the distal orientation. The mean fractal dimension was 1.47; the mean damping value for palatal orientation was 12.3%, while that for the distal orientation was 8.2%. No significant correlation was found.

Conclusions

Damping values, measured at peri-implant bone, were found not to be related to a radiographic parameter of trabecular bone pattern like the fractal dimension. The clinical implication would be that Osstell^™ graphs displaying distinct or more rounded peaks might both indicate a stable implant as long as the associated implant stability quotients are in the range of satisfactory values proposed in the literature.