TY  - JOUR
A1  - Becker, Kathrina
A1  - Schwarz, Frank
A1  - Rauch, Nicole Jasmin
A1  - Khalaph, Silava
A1  - Mihatovic, Ilja
A1  - Drescher, Dieter
T1  - Can implants move in bone? A longitudinal in vivo micro‐CT analysis of implants under constant forces in rat vertebrae
T2  - Clinical oral implants research
N2  - Objectives: Whereas stationary stability of implants has been postulated for decades, recent studies suggested a phenomenon termed implant migration. This describes a change in position of implants as a reaction to applied forces. The present study aims at employing image registration of in vivo micro‐CT scans from different time points and to assess (a) if migration of continuously loaded implants is possible and (b) migration correlates with the force magnitude.
Material and methods: Two customized machined implants were placed in the dorsal portion of caudal vertebrae in n = 61 rats and exposed to standardized forces (0.5 N, 1.0 N, and 1.5 N) applied through a flat nickel–titanium contraction spring, or no forces (control). Micro‐CT scans were performed at 0, 1, 2, 4, 6, and 8 weeks after surgery. The baseline image was registered with the forthcoming scans. Implant migration was measured as the Euclidean distance between implant tips. Bone remodeling was assessed between the baseline and the forthcoming scans.
Results: The findings confirmed a positional change of the implants at 2 and 8 weeks of healing, and a linear association between applied force and velocity of movement (anterior implant: χ2 = 12.12, df = 3, and p = .007 and posterior implant: χ2 = 20.35, df = 3, and p < .001). Bone apposition was observed around the implants and accompanied by formation of load‐bearing trabeculae and a general cortical thickening close and also distant to the implants.
Conclusion: The present analysis confirmed that implants can migrate in bone. The applied forces seemed to stimulate bone thickening, which could explain why implants migrate without affecting stability.
KW  - bone‐screw
KW  - implant movement
KW  - implant stability
KW  - in vivo micro‐CT
KW  - orthodontic mini‐implant
Y1  - 2019
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/56301
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-563017
SN  - 1600-0501
SN  - 0905-7161
N1  - http://creativecommons.org/licenses/by-nc-nd/4.0/
SP  - 1179
EP  - 1189
ER  -