Bone and Periodontal Tissue Regeneration by the Secretomes from Bone Marrow Derived Mesenchymal Stem Cells - New Trends in Tissue Engineering and Regenerative Medicine - page 104

Dental X-ray films were placed parallel to the tooth axis, and radiographic images of the defect
site were ta-ken in the buccolingual direction. The defect sites were dissected and fixed in 10%
neutral-buffered formalin (Wako, Japan) 4 weeks after transplantation. The specimens were
decalcified in Plank-Rychro solution (Wako) for 8 weeks, routinely processed into 5μm-thick
paraffin-embedded sections, stained with hematoxylin and eosin, and observed under a light
microscope (Olympus). Histometric parameters were quantified using a computer-based
image analysis system (Image J 1.44; National Institutes of Health). The following parameters
were analyzed:
1. Cementum regeneration height: distance from the root surface notch to the coronal
extension of newly formed cementum on the root surface.
2. Bone regeneration height: distance from the root surface notch to the coronal
extension of newly formed bone along the root surface.
3. Bone regeneration area: area of new alveolar bone formed coronally from the apical
extension of the root surface notch.
Clinical healing was generally uneventful. The results from the histometric analysis are shown
in Fig. 8. The cementum regeneration height, the bone regeneration height, and the bone
regeneration area of the MSC-CM group were 3.01 ± 0.16 mm, 3.19 ± 0.51 mm, and 4.89 ± 1.08
mm 2 , respectively. A large amount of new lamellar and woven bone formation was observed
in the MSC-CM group. Thick-layered and cellular cementum on the root surface was also
frequently observed in the MSC-CM group.
On the other hand, less newly regenerated bone and cementum compared to the MSC-CM
group was observed in the PBS group. Dense collagen fibers were observed frequently in the
PBS group. Newly regenerated bone and cementum were not apparent in the defect group.
Furthermore, there was minimal inflammatory cell infiltration in the MSC-CM group com‐
pared to the other groups.
Figure 7. Representative photomicrographs and radiographic images from sites receiving experimental materials.