Perfection v700 pro scanner

Intraoral radiographs were taken at all follow-up visits starting 3 months after crown insertion with the long-cone paralleling technique centering the alveolar crest (Hawe X-ray film holder; Kerrhawe SA, Bioggio, Switzerland). The x-ray machine (X mind®, Aceton Germany GmbH, Düsseldorf, Germany) was set to 70 kV and 0.32 mA for the upper jaw and 0.25 mA for the lower jaw respectively. The film-based images (Kodak Ultraspeed, Rochester, USA) were scanned and digitalized (Epson Perfection V700 Pro Scanner, at 1200 dpi).
Images were checked for sufficiency by the visibility of sharp implant threads.
The approximal marginal bone levels (MBL = distance between the implant shoulder and the first bone-to-implant contact (Buser, Weber, Bragger, Balsiger, 1991; Weber, Buser, Fiorellini, Williams, 1992) (link)) were calculated as the mean values of mesial and distal measurements (Image J, Version 1.44; U.S. National Institutes of Health, Bethesda, MD, USA) Negative values represent bone levels coronal to the implant shoulder, positive value represent bone levels apical to the implant shoulder. Dimensions were calibrated using the implant diameter.
The primary endpoint was the median buccal vertical defect depth (distance first bone to implant contact and implant shoulder) at 6.8 -8 years after implant placement.

For the evaluation of the marginal bone level, intraoral radiographs were taken using the long-cone paralleling technique with the central beam directed to the alveolar crest (Hawe x-ray film holder, Kerrhawe SA, Bioggio, Switzerland). The images were digitalized with a scanner (Epson Perfection V700 Pro Scanner) in a resolution of 1200 dpi.
The marginal bone level (MBL), i.e. the distance between the implant shoulder and the first visible bone-to-implant contact, was measured at the mesial and distal aspect with a 10-15x magnification (Buser et al. 1991 , Weber et al. 1992 ) using an image analysis program (Image J, Version 1.44, U.S. National Institutes of Health, Bethesda, Maryland, USA). In order to adjust each radiograph for distortion they have been calibrated by a reference structure, which was the well-known implant diameter.