Cell viability and distribution within the scaffolds were regularly monitored over a period of 36 days using a laser scanning microscopy. Figure 3 shows confocal images of stained MC3T3-E1 on day 7, 14, 21, and 36. In the scaffolds loaded with a Gel-MOD/cell suspension, the cells were at first evenly distributed in the Gel-MOD, like in the control pellet. After a few days, the cells started to migrate to the PLA scaffolds and stretched along the structure. In the control pellet the cells formed small clusters. This is most likely due to proliferation of the cells as observed in previous reports . One week after encapsulation, LSM revealed that 95% of the cells in the PLA scaffold were alive after live–dead staining. In the second week, the cell number in the pellet was 30% lower than one week after encapsulation, and stayed constant during the second and third week, just latter, 36 days after encapsulations, cell number dropped to 46% compared to the first week. Similarly, a substantial drop in cell number was observed within the Gel-MOD pellet. One week after encapsulation 95% of the cells in the pellet were alive, but cell number was decreasing to 80%, 48%, and 40% for the second week, third week, and 36 days, respectively, compared to the first imaging. Moreover, the cells in the pellet had a more round morphology while the cells in the scaffolds were stretching along the pores. SEM image of 36 days old PLA/Gel-MOD scaffold (Fig. 4) shows that there are still cells stretching along the PLA structure, but also some Gel-MOD with cells embedded into it.