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In this prospective study we evaluated the duration of insertion and the accuracy of fitting of computer-aided design (CAD)-based pre-bent orbital floor plates compared with non-preformed orbital plates in reconstruction of the orbital floor. Thirty-six patients with unilateral fractures of the orbital floor were included; pre-bent plates were used in 25 and non-preformed plates in 11. Preoperative computed tomography (CT) scans were used for CAD of individualised implants. The anatomy of the affected orbit was virtually reconstructed "slice by slice". Individually pre-bent plates were generated using a stereolithographic model of the reconstructed orbit. The mean (SD) duration of insertion was significantly reduced when pre-bent orbital plates were used (5.5 (5.4) min) compared with non-preformed meshes (11.1 (7.7) min). The congruence of pre-bent plates to the infraorbital rim did not differ from that of non-preformed plates. The accuracy of fit was rated as "accurate" in 24 cases. CAD-based individualised titanium meshes reduce theatre time compared with non-preformed orbital plates. Our results confirm the efficacy of CAD-based pre-bent plates in reconstruction of the orbital floor. [ABSTRACT FROM AUTHOR]

The pathogenesis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) remains unknown, and the development of a reliable experimental model would help to improve our understanding of it. We used 12 domestic pigs of which 6 made up the experimental group and were treated with zoledronate 4 mg intravenously weekly for 5 weeks, while the control group (n = 6) were given no drugs. On day 60 the right second maxillary and mandibular third molars were extracted. Thirty days later 3 animals in each group were killed; the rest were killed 90 days later. Histopathological specimens from the extraction sites were analysed for bone density, collagen architecture, density of osteons, and the amount of non-mineralised bone. Bone density, amount of non-mineralised bone, and density of osteons differed significantly between the 2 groups (p < 0.001 in each case), but the chromatic pattern dictated by the collagen architecture did not. Our results correspond to the observations that have been made in patients with BRONJ, which means that the histomorphometric conditions seen in patients can be reproduced in this experimental setting. [ABSTRACT FROM AUTHOR]

Objectives The animal study aims to evaluate a new experimental model for measuring sole the influence of the surface characteristics independent from implant macro-design on the level of osseointegration by registering the pull-out strength needed for removal of experimental devices with different surfaces from artificial defects. Material and methods Seventy-two test bodies (36 with the FRIADENT ® plus surface, 36 with the P15/HAp biofunctionalized surface) were inserted in six adult domestic pigs with artificial calvarial defects. The experimental devices were designed to fit in the defects leaving a gap between the test body and the local bone. After 21 days of healing, the animals were sacrificed and the test bodies were pulled out with a standardised reproducible pull-out device measuring the pull-out strength. The pull-out strength for both groups was compared. Results Twenty-one days after insertion a mean force of 412 ± 142 N for the P15/HAp group and 183 ± 105 N for the FRIADENT ® plus group was measured for the removal of the specimens from the calvarial bone. The difference between the groups was statistically significant (p < 0.0001). Conclusion The experimental set-up seems to be a suitable method when measuring the impact of implant surfaces on the early stage of osseointegration. [ABSTRACT FROM AUTHOR]