[Research of TC-PHBHHx/ß-TCP compounds for treatment of dry socket in SD rats].

PURPOSE: The effects of different compounds on dry socket were evaluated in order to find a new method that can both be antibacterial and osteogenic,providing experimental evidence for future clinical application. METHODS: Seventy-two male SD rats, with upper left anterior teeth been extracted, were infected by pus to result in dry socket.Seven days later, they were allocated randomly and evenly into 4 groups and received different treatment, i.e. group A: debridement; group B: debridement and filled with iodoform gauzes; group C: debridement and filled with periocline; group D: debridement and filled with TC-PHBHHx/ß-TCP. After being treated for 1,4,8 weeks, sequential fluorescent labeling was performed. The animals were sacrificed after the procedure and hard tissue and decalcified sections were harvested for histological and histomorphometrical evaluation. Statistical analysis was performed using SPSS 19.0 software package. RESULTS: At the same time point, the results of osteogenesis in group A, B and C were not significantly different while the results in group D was significantly different from other groups; accordingly, significant new bone formation was observed. At different observation time, the bone area in group B and C were not significant different over time. In group A, little new bone formation was found but surrounded by a large amount of inflammatory cells at 8 week. However, group D showed bone area increasing gradually with time. CONCLUSIONS: TC-PHBHHx/ß-TCP has significant anti-inflammatory and osteogenic effects. Iodoform gauzes and periocline have good anti-inflammatory results but not significant osteogenic effects.

[Expression and significance of secreted frizzled-related protein 1 and ß-catenin in gingival tissue of patients with chronic periodontitis].

OBJECTIVE: This study aimed to investigate the expression and correlation of secreted frizzled-related protein 1 (SFRP1) and ß-catenin in gingival tissues of patients with chronic periodontitis (CP). The role of the classical Wnt/ß-catenin signaling pathway in the development of periodontitis was also explored. METHODS: Twenty-eight patients with CP (CP group) were enrolled in this study. Among them, 16 cases were moderate CP, and 12 demonstrated severe CP. Twelve healthy cases comprised the controls (normal group). Gingival tissue was collected, and the probing depth, bleeding index, and clinical attachment loss were recorded. The expression levels of SFRP1 and ß-catenin were detected by immunohistochemistry, and staining intensity was evaluated by double scoring method. SPSS 19.0 was used for statistical analysis. RESULTS: The staining strength scores of SFRP1 and ß-catenin were 2.16±0.65 and 1.12±0.51 in the normal group, 3.57±0.45 and 2.36±0.49 in the CP group, 3.61±0.40 and 2.30±0.44 in the moderate CP group, and 3.52±0.52 and 2.45±0.55 in the severe CP group, respectively. The expression of SFRP1 and ß-catenin in the CP group was higher than that in the normal group (P<0.01). A significant difference was noted between the normal group and the moderate and severe CP groups (P<0.01) but none between the moderate and severe CP groups (P>0.05). A positive correlation was found between the expression of SFRP1 and ß-catenin (r=0.657, P<0.01). The expression levels of ß-catenin and SFRP1 were related to periodontal indexes. The correlation between the expression of SFRP1 and probing depth was most significant (r=0.723, P<0.01), as well as that between ß-catenin and bleeding index (r=0.697, P<0.01). CONCLUSIONS: Patients with CP exhibit elevated expression of SFRP1 and ß-catenin in gingival tissues, and this event is related to the degree of periodontal destruction. Abnormal expression of SFRP1 and ß-catenin may promote the development of periodontitis.

[Detection of Dickkopf-1 and alkaline phosphatase activity in gingival crevicular fluid from chronic periodontitis with Er:YAG laser as an adjunctive treatment].

PURPOSE: The aim of this study was to evaluate the clinical efficacy and the level of DKK1 and alkaline phosphatase (ALP) activity in gingival crevicular fluid (GCF) while taking Er:YAG laser as an adjunctive to scaling and root planning in the treatment of chronic periodontitis (CP). METHODS: Eleven patients with CP were included and there were nineteen pairs of homonym teeth(thirty-eight teeth) in this split-mouth design, and they were randomly assigned to experimental group or control group. In the experimental group, a combination of ultrasonic subgingigval scaling and root planning with hand instrument (SRP) were performed with Er: YAG laser as an adjunctive; in the control group, only SRP was performed. The main variables were bleeding index (BI), probing depth (PD), clinical attachment loss (CAL) which were assessed at baseline (1 week after ultrasonic subgingival scaling), l month and 3 months after treatment. GCF was collected at baseline, l week, l month and 3 months, and the levels of DKK1 and ALP activity were detected at the same time point. The data were analyzed with SPSS 19.0 software package. RESULTS: Both groups showed significant reduction of PD, CAL, BI values 1 month and 3months after treatment, but no significant difference in clinical parameters were found between the two groups. In the experimental group, the activity of ALP reduced to (386.69±146.42), (341.221±171.62), (249.27±98.72) from (396.191±150.55) U/L and the level of DKK1 dropped to (310.34±184.68), (270.04±55.14), (247.31±56.99) from (307.12±45.63) µg/L at the end of 1 week, 1 month, 3 months, respectively. Meanwhile, in the control group, the activity of ALP reduced to (374.72±131.27), (344.42±127.80), (252.36±90.4 ) from (394.09±120.25) U/L and the level of DKK1 dropped to (310.34±84.68), (270.04±55.14), (247.31±56.99) from (305.33±147.40) µg/L at the end of l week, l month, 3months, respectively. There is no significant difference between the two groups at any period for ALP or DKK1. CONCLUSIONS: Er:YAG laser was a safe no-surgical adjunctive therapy in treating chronic periodontitis, further observation is needed to determine its long-term effectiveness.