Fig. 2

Histomorphometric analysis. Light micrographs of control (a–c), FS (d–f) and ATSCs + FS groups (g–i). a In the control group, resorption of cementum and dentin surfaces were filled with newly formed bone in the areas of ankylosis (arrow heads). b Inflammatory resorption of root surface (arrow), lymphocytes (double headed arrow—insert) and increase fibroblastic activity (asterisk—insert). c Inflammatory resorption of surfaces (arrows) and areas of ankylosis with new bone formation (asterisk). d Besides the regular alignment of PDL, the regeneration and resorption on the surfaces (arrow heads), some ankylosis (arrow) areas near the root surface were prominent. e Regenerated regular contour of cement (arrow heads). f Regular alignment of PDL (arrows). g Regular alignment of PDL and contour of cement (arrows), intense vascularization around the alveolar bone (asterisk). h Regenerated regular contour of cement (arrow heads). i Regular alignment of PDL (arrows)