Quality by design driven development and evaluation of thermosensitive hydrogel loaded with IgY and LL37-SLNs to combat experimental periodontitis.

Egg yolk immunoglobulin (IgY) and LL37, potent antibacterial substances, can fight against periodontitis. This work aimed to develop a locally injectable hydrogel for potential co-delivery of special IgY and LL37-loaded solid lipid nanoparticles (LL37-SLNs) to synergistically inhibit the proliferation of oral pathogens, thus relieving periodontal inflammation and redness. The formulation of thermosensitive hydrogel loaded with IgY and LL37-SLNs was developed by adopting the Quality by Design approach. Then the formulations were optimized by two-factor three-level full factorial design by Design-Expert software. Finally, the optimized formulation was characterized and estimated in vitro and in vivo. In vitro release and antibacterial activity studies have revealed that the optimized formulation was homogeneous and can be released slowly, with sustainably antibacterial power. And the physical and chemical composition analysis and morphological observations further confirmed the sustained-release capability. On the other hand, in vivo studies proved that the optimized formulation significantly decreased gingival redness, bleeding, and plaque formation, avoided excessive resorption of alveolar bone, and reduced the levels of inflammatory factor in periodontitis rats. In conclusion, the optimized thermosensitive hydrogel loaded with IgY and LL37-SLNs may be a promising local sustained-release preparation for the effective treatment of periodontal diseases.

[Effect of platelet rich fibrin combining with Bio-oss to treat furcation involvement].

PURPOSE: To evaluate the effect of platelet rich fibrin (PRF) combining with Bio-oss in treating Class II furcation involvement. METHODS: Thirty patients who had Class Ⅱ furcation involvement in the mandibular first molar were included. They were all free of systemic disease. After initial periodontal therapy, they were randomly divided into 2 groups. In the experimental group, PRF combining with Bio-oss were placed in the areas with furcation defect and covered with PRF. In the control group, only flap surgery was performed. All patients were followed up for 6 months after operation. The efficacy was evaluated with clinical parameters and cone-beam computed tomography (CBCT). The data were analyzed with SPSS 2.0 software package. RESULTS: Periodontal indexes including probing depth (PD), clinical attachment loss (CAL), horizontal probing depth (HPD) significantly decreased in both groups after operation (P<0.05); alveolar bone significantly increased in the experimental group (P<0.05). CONCLUSIONS: The clinical effect of PRF combined with Bio-oss on Class II furcation involvement are remarkable.

[Effect of photodynamic therapy on IL-1beta and MMP-8 in gingival crevicular fluid of chronic periodontitis].

PURPOSE: Photodynamic therapy (PDT) is used in infectious disease for its antimicrobial effects. The aim of the study is to evaluate the effects of a diode laser-based photodynamic therapy on the treatment of chronic periodontitis. METHODS: Fifty eight patients with chronic periodontitis were divided into three groups. Group A was treated with scaling and root planing (SRP) plus photoactivated disinfection therapy for one time (Periowave(TM): a diode laser with a wavelength of 670nm and 0.01% methylene blue solution). In group B, the patients were treated with SRP followed by photoactivated disinfection, and a second photoactivated disinfection treatment 6 weeks later. Group C was treated with SRP alone. The irradiation time was 60 seconds at a power output of 140mW. Gingival crevicular fluid (GCF) samples from these three groups of patients were obtained before periodontal treatment, 6 weeks and 12 weeks after treatment. GCF was collected using a paper strip, and enzyme-linked immunoabsorbent assay (ELISA) was performed to determine the cytokine (IL-1beta and MMP-8) levels. The data were analyzed with SAS 6.12 software package. RESULTS: ELISA showed IL-1beta and MMP-8 levels of all groups were decreased significantly at 6-week after treatment compared to pretreatment levels. No significant inter-group differences were noted. At 12-week after treatment, the decreases in IL-1beta levels of group A and B and the decrease in MMP-8 level of group B were significantly higher than group C (P<0.05). CONCLUSIONS: Based on these findings, it appears that SRP and SRP with PDT are all effective for chronic periodontitis, but the effect of SRP with PDT may last longer. PDT therefore appears to be a useful adjunct to SRP for chronic periodontitis therapy. Supported by National "Tenth Five-Year" Key Science and Technology Research Project (Grant No.2004BA72026) and International Cooperation Project (Grant No.051012).

[Detection and significance of IL-1beta and MMP-8 in patients with periodontitis of whole unstimulated saliva].

PURPOSE: To detect the role of IL-1beta and MMP-8 by ELISA in whole unstimulated saliva of patients with different type of periodontitis and to determine whether they are possible specific biomarkers of periodontitis. METHODS: A total of 80 saliva samples were collected from 28 GCP patients, 28 GAgP patients and 24 healthy subjects. The levels of IL-1beta and MMP-8 were respectively measured by ELISA kits. The data were analysed statistically with one-way ANOVA. RESULTS: The mean salivary levels of IL-1beta in GCP group,GAgP group and control group were 144.40 pg/ml+/-150.70 pg/ml+/-72.56 pg/ml+/-69.36 pg/ml and 65.96 pg/ml+/-71.18 pg/ml respectively, There was no significance difference between the three groups (P>0.05); GCP and GAgP groups presented significantly elevated salivary levels of MMP-8 than that of the control group, which was (576.89+/-559.24) ng/ml, (420.93+/-533.73)ng/ml and (151.49+/-216.38) ng/ml respectively (P<0.05), while there was no significant difference between GCP and GAgP group (P>0.05). CONCLUSION: Salivary levels of MMP-8 may be a biomarker for diagnosis for periodontitis while IL-1beta needs to be further testified.