ABSTRACT
Objective @# The present study observed the clinical effects on reattachment and pulpotomy of young crown-fractured and pulp-exposed permanent incisors. @*Methods @#In a one-year retrospective clinical observation study, 30 traumatic intact segments of permanent incisors with crown fracture and pulpal exposure were treated using a pulpotomy and reattachment technique with an enamel-dentin luting agent and composite resin. @*Results @#The number of subsequent visit teeth was 30, 29, 25 at 1, 3, 6 months follow-up respectively. The pulpotomy success rates were 100% at 1 month, 93.1% at 3 months, 93.1% at 6 months. The retention rates using the reattachment technique were 100% at 1 month, 100% at 3 months, 100% at 6 months.@*Conclusion@#Pulpotomy is the preferred method of preserving live pulp after pulpal exposure of young permanent incisors, and the clinical effect is prominent. The fragment reattachment technique is an effective middle- and short-term method for temporary restoration of young crown-fractured permanent incisors.
ABSTRACT
Objective @#This study aimed to investigate the effect of cAMP-responsive-element-binding protein (CREB) overexpression on the differentiation of human stem cells from the apical papilla (hSCAPs), stimulated by transforming growth factor- beta (TGF-β1). @*Methods@#Cells were isolated from human immature third molars via enzymatic digestion. Four experimental groups were set up: ①a control group, receiving normal mineralization inducer (α-MEM, 10% FBS, 10 mmol/L β-sodium glycerophosphate, 50 μg/mL vitamin C, 10 nmol/L dexamethasone); ② a TGF-β1 group, receiving normal mineralization inducer and 5 μg/mL TGF-β1; ③ a TGF-β1+LV-empty group, receiving normal mineralization inducer and the transfected empty virus vector with 5 μg/mL TGF-β1; and ④ a TGF-β1+ov-CREB group, receiving normal mineralization inducer and the transfected CREB-overexpressing viral vector, with 5 μg/mL TGF-β1. The transfected cells were cultured in odontogenic medium in the presence or absence of TGF-β1 for 2 weeks. Alizarin red staining was used to detect mineralized nodules, and the mRNA expression of the mineralization genes runt-related transcription factor 2 (RUNX2), dentin sialophosphoprotein (DSPP) and alkaline phosphatase (ALP) was measured by qPCR. @*Results @#Compared with the control group (1.12 ± 0.11), TGF-β1 inhibited the deposition of calcium minerals (0.67 ± 0.12) (P < 0.05) via hSCAPs and inhibited the mRNA expression of RUNX2 (0.60 ± 0.03), DSPP (0.43 ± 0.12) and ALP (0.69 ± 0.05) (P < 0.05). In contrast, overexpression of CREB attenuated the effect of TGF-β1 on hSCAPs, resulting in the development of a high number of mineralized nodules (1.27 ± 0.10) (P < 0.01) and increased RNA levels of RUNX2 (1.33 ± 0.07), DSPP (1.32 ± 0.11) and ALP (1.26 ± 0.03) (P<0.05) compared with those in the TGF-β1 group. @*Conclusion@#Overexpressed CREB promotes odontogenic differentiation of hSCAPs by interfering with TGF-β1.