Methods: Under approval of the Georgia Tech IACUC, six C57Bl/6J male mice (Jackson Labs) were euthanized at specific ages: every two days from day P6 until P18, every day from P19 until P30, every five days from P35 until P50, P56, P70, and P107. The PF sutures were scanned with µCT (vivaCT40, Scanco Medical) and processed using the algorithm. The edges of the suture were analyzed to find: the distances between the bones of the suture, the suture area, the suture mass and density, and the percentage of the suture that is open.
Results: The results show that PF suture fusion began on day P6 and was completed by day P20, moving in an anterior to posterior direction. The mass of bone in the suture remained constant during fusion and on day P20 began a dramatic increase until reaching a plateau at P30 (Fig 3). Unlike the spatial variations seen with the distance measurements, the increase in bone mass occurred uniformly along the majority of the suture.
Conclusion: Micro-CT imaging with Snake Algorithm segmentation was used to show that the PF suture closes two weeks earlier than previously reported and further suggest that suture closure is controlled differently than the mineralization.