Amniotic membrane and adipose-derived stem cell co-culture system enhances bone regeneration in a rat periodontal defect model.

BACKGROUND/PURPOSE: Periodontal disease is a chronic inflammatory process that potentially leads to alveolar bone destruction and tooth loss. Tissue engineering combined with stem cell therapy is a potential effective treatment for periodontal bone loss. Amniotic membrane (AM) is a potential scaffold enriched with multiple growth factors. It has the effects of anti-inflammation, antiangiogenesis, and immunosuppression. Herein, we used adipose-derived stem cells (ADSCs) and an AM co-cultured system to study bone regeneration in a rat periodontal defect model in vivo. METHODS: Human ADSCs were isolated from the infrapatellar fat pad, and characterized by flow cytometry, reverse transcription-polymerase chain reaction, and multipotent differentiation assays. The co-culture system was applied in the periodontal two-wall osseous defect in a rat model, and computed tomography was used to measure the effect. RESULTS: Human ADSCs isolated from the infrapatellar fat pad showed spindle-like morphology. Flow cytometry results demonstrated that ADSCs expressed a high level of CD90 and CD105, but not CD31, CD34, and CD45. ADSCs strongly expressed stemness genes, including SOX2, OCT4, NANOG, and KLF4 on different passages. Furthermore, ADSCs were able to differentiate into osteogenic, chondrogenic, and adipogenic cells. In the periodontal osseous defect rat model, ADSCs and the AM co-culture system significantly increased bone regeneration. CONCLUSION: This study provides the basis for using ADSCs with an AM co-culture system as stem cell therapy and scaffold transplantation in clinical periodontology.

Evaluation of the root and root canal systems of mandibular first premolars in northern Taiwanese patients using cone-beam computed tomography.

BACKGROUND/PURPOSE: Cone-beam computed tomography (CBCT) can provide valuable data for root canal systems of human teeth in vivo. This study used CBCT to evaluate the number of roots and canals of 300 mandibular first premolars in 150 northern Taiwanese patients. METHODS: The root canal systems of 300 mandibular first premolars in 150 northern Taiwanese patients with bilateral premolars were analyzed by CBCT. RESULTS: Of the 300 mandibular first premolars, 197 (65.7%) had one root with one canal (1R1C), 49 (16.3%) had one root with two canals (1R2C), 51 (17.0%) had two roots with one canal in each root (2R2C), and three (1.0%) had three roots with one canal in each root (3R3C). Statistical analyses showed that women had a significantly higher incidence of 1R1C mandibular first premolars (71.4%) than men (58.8%, p = 0.031), and men had a significantly higher incidence of 2R2C mandibular first premolars (27.2%) than women (8.5%, p < 0.001). One hundred and twenty-two (81.3%) of the 150 patients had a symmetrical root and root canal system between the right and left mandibular first premolars. Men had a significantly higher symmetrical rate of 2R2C mandibular first premolars (26.5%) than women (8.2%, p = 0.013). CONCLUSION: Approximately 82% of mandibular first premolars in northern Taiwanese patients have one root with either one or two canals. There are significant differences in the number of roots and canals and symmetry of the root canal system of bilateral mandibular first premolars between male and female northern Taiwanese patients.