To investigate the clinical outcomes, including survival and periapical healing rates and failure causes, of root canal treatment for patients with periapical lesion. A retrospective cohort study was conducted which enrolled patients admitted for the evaluation and management of periapical lesion with root canal treatment. The primary predictor variables were difficulty assessment of root canal therapy (DARCT),which was divided into lower（DARCT =3-4）, medium (DARCT =5-7) and higher (DARCT =8-9) difficulty root canal, in terms of canal length, curvature and calcification. The primary outcome measurement was the incidence of periapical healing and survival rate. Potential confounders included patient demographics, canal number, root canal filling, and coronal restoration. SPSS 21.0 software package was used for data analysis. The 5-year survival rate was 81.4%(83/102) and healing rate was 77.1% (64/83). DARCT was significantly associated with the survival rate(P=0.017). Root fracture, deep pockets lesions and periodontal abscess were observed in DARCT with a value of 8-9(P=0.027), leading to tooth extraction. The teeth with multiple root canals were extracted due to recurrent or persistent periapical lesion (P=0.004). Chi-square test showed that root canal number (P=0.021), quality of root canal filling (P=0.006) as well as DARCT (P=0.000) were significantly correlated with the final healing rate. Multivariate logistic regression analysis showed that DARCT (P=0.000) and the quality of root canal filling (P=0.033) were associated with the final healing rate. DARCT and the quality of root canal filling play key roles in the clinical prognosis of periapical lesion, DARCT and number of root canal are more likely to be correlated with failure.DARCT and the quality of root canal filling play key roles in the clinical prognosis of periapical lesion, DARCT and number of root canal are more likely to be correlated with failure. To explore the advantages of fiber reinforced composites veneer in repairing discolorated and defective anterior teeth. Twenty porcelain veneers and 20 fiber reinforced composites veneers specimens of 2 cm long, 2 cm wide and 1 mm in thickness, with a longitudinal cross section of 45° incline were made. Another 40 fiber reinforced composites specimens of the same shape were used for comparison. FHT-1015 Epigenetic Reader Domain inhibitor After polishing and acid treatment of all the specimens according to clinical routine, resin cement was used for bonding the porcelain cover with resin veneers slope, and the conjunct specimens were soaked in 40 ℃ warm water for 24 h and drying; then the two groups of specimens were put were put on the pressure testing platform of the universal testing machine, with 1 mm/min testing pressure, and 1 cm square head was contacted on the surface of the bonding interface. Computer was used to record the fracture process of the two groups of specimens and the maximum compressive strength of bonding interface automatically. The compressive strength of the bonding interface under the same conditions was evaluated. SPSS 12.0 software package was used for statistical analysis. The compressive strength of the bonding interface between fiber reinforced composites was significantly higher than that between porcelain and fiber reinforced composites(P<0.05). Compared with porcelain veneers that can not be repaired when damaged in the anterior teeth, high-strength fiber resin veneers can partially be repaired with the same material, which has obvious advantages.Compared with porcelain veneers that can not be repaired when damaged in the anterior teeth, high-strength fiber resin veneers can partially be repaired with the same material, which has obvious advantages. To evaluate the existence of tertiary lymphoid structures(TLS) in oral lichenoid lesions and its compositional characteristics of immune cells. Tissue samples of normal oral mucosa, oral lichen planus (OLP) and oral lichenoid tissue reaction(OLTR) were collected, thirty cases in each group. Hematoxylin-eosin(H-E) staining was performed to identify the TLS-like structures, and immunohistochemistry (IHC) staining was applied to assess the structure and amount of infiltrating CD3+ T cells, CD19+, CD20+ B cells, CD21+ follicular dendritic cells (FDC), Bcl-6+ germinal centers, CD34+ PNAd+ venules and CD34+ Gp36+ micro lymphatic vessels in TLS of OLL. Histopathology and molecular markers were used to evaluate the morphological performance of TLS in OLL. Chi-square test (Fisher exact probability method) was applied to compare the proportion of TLS in each group; integral optical density (IOD) method was used to calculate the expression level of each molecular marker, nonparametric t test (Mann-Whitney U test) was in OLL lesions, mainly presented as non-classical forms. The classical forms can be occasionally found. CD20 and CD21 can be used as the biomarkers to identify the TLS in OLL. TLS can not be used as the diagnosing criteria for identifying OLP or OLTR.TLS exists in OLL lesions, mainly presented as non-classical forms. The classical forms can be occasionally found. CD20 and CD21 can be used as the biomarkers to identify the TLS in OLL. TLS can not be used as the diagnosing criteria for identifying OLP or OLTR.Pseudomonas aeruginosa is an opportunistic pathogen that causes thousands of deaths every year in part due to its ability to form biofilms composed of bacteria embedded in a matrix of self-secreted extracellular polysaccharides (EPS), e-DNA, and proteins. In chronic wounds, biofilms are exposed to the host extracellular matrix, of which collagen is a major component. How bacterial EPS interacts with host collagen and whether this interaction affects biofilm viscoelasticity is not well understood. Since physical disruption of biofilms is often used in their removal, knowledge of collagen's effects on biofilm viscoelasticity may enable new treatment strategies that are better tuned to biofilms growing in host environments. In this work, biofilms are grown in the presence of different concentrations of collagen that mimic in vivo conditions. In order to explore collagen's interaction with EPS, nine strains of P. aeruginosa with different patterns of EPS production were used to grow biofilms. Particle tracking microrheology was used to characterize the mechanical development of biofilms over two days.