Fig. 10

a Ultrasonic imaging at the implant in region 14 revealed a buccal bone loss up to the 12th thread (asterisk marks the implant-abutment interface; circle marks the bone). b Ultrasonic imaging at the implant in region 13 revealed a buccal bone loss up to the 14th thread (asterisk marks the implant-abutment interface; circle marks the bone). c Ultrasonic imaging at the implant in region 12 could not be visualized from the buccal side due to its anatomical situation (subnasal position). Imaging palatal to the implant showed bone loss up to the 13th thread. The palatal image is severely distorted because it was not possible to place the probe parallel to the implant on the oblique palate, and so it was impossible to visualize the apical bone edge (asterisk marks the implant-abutment interface)