Comparison of the inflammatory states of serum and gingival crevicular fluid in periodontitis patients with or without type 2 diabetes mellitus.

Background/purpose:There is a two-way relationship between periodontitis and type 2 diabetes mellitus. This study aimed to compare the inflammatory states in serum and gingival crevicular fluid (GCF) in periodontitis patients with or without type 2 diabetes mellitus (T2DM) and healthy subjects. Materials and methods: 20 subjects were systematic and periodontal healthy (H group), 40 subjects were with periodontitis (CP group), and other 40 were with periodontitis and type 2 diabetes mellitus (DC group). Fasting blood glucose (FBG) and HbA1c was tested. GCF and serum level of interleukin (IL) -17, visfatin, receptor activator of nuclear factor-kappa B (NF-κB) ligand (RANKL)/osteoprotegerin (OPG) ratio were measured. Results: The GCF volume, total amount of IL-17, vastatin, RANKL/OPG ratio in GCF and their concentrations in serum were higher (P < 0.05) in CP and DC groups than in H group, which were also higher (P < 0.05) in DC group than in CP group except for visfatin in GCF and IL-17 in serum. At sample sites of PD ≤ 3 mm, GCF volume, IL-17, visfatin and RANKL/OPG ratio in DC and CP groups were higher (P < 0.05) than that in H group, which were also higher in DC group than in CP group either with PD ≤ 3 mm or PD > 3 mm. Inflammatory state in GCF was positively correlated to systemic inflammation, and both of them were positively correlated to FBG. Conclusion: Moderate and severe periodontitis aggravated systemic inflammation. T2DM together with periodontitis resulted in more severe systemic inflammation. The positive correlation between the periodontal and systemic inflammation and their association with FBG indicated an inflammatory link between periodontitis and T2DM.

Multilevel Analysis of Non-surgical Periodontal Treatment of Patients with Generalised Aggressive Periodontitis.

OBJECTIVE: To investigate various factors affecting the clinical outcome of nonsurgical periodontal treatment and evaluate the treatment effects of adjunctive amoxicillin and metronidazole (AMX + MET) in patients with generalised aggressive periodontitis (GAgP). METHODS: Forty-two patients with GAgP were recruited and randomly assigned to three groups: scaling and root planing (SRP) only, AMX + MET after SRP, and AMX + MET during SRP. The patients were assessed every 2 months post-therapy. Periodontal clinical and subgingival microbiological parameters were analysed at baseline and 6 months post-therapy. The impacts of different covariates on pocket probing depth (PD) reduction were evaluated. RESULTS: A multilevel analysis revealed that 58% of the variability in PD reduction was attributed to site-level parameters, 27.3% to patient-level parameters and 18.7% to tooth-level parameters. Greater PD reduction can be expected at initially deeper PD sites and sites with intrabony defects, and in patients with adjunctive use of AMX + MET. Persistent Tannerella forsythia infection and tooth mobility after treatment were negatively associated with PD reduction. CONCLUSION: The clinical outcomes of nonsurgical periodontal treatment were mainly influenced by site-level parameters, and adjunctive use of AMX + MET can lead to better clinical results in patients with GAgP in a short time.

Influence of local anesthesia on the outcomes of non-surgical periodontal treatment.

BACKGROUND: There is limited evidence of the effects of local anesthesia (LA) on outcomes of non-surgical periodontal treatment (NSPT), in particular among the Chinese. This retrospective cohort study aimed to evaluate the effects of LA on short-term treatment outcomes of NSPT and to determine under what circumstances LA should be prescribed to improve these outcomes. METHODS: Data from periodontal examinations of 3980 patients were used. The data were from 3-month re-evaluation records of an electronic periodontal charting record system in the Department of Periodontology of Peking University School and Hospital of Stomatology from June 2008 to January 2015. Descriptive analyses included changes in probing depth (PD) and the Mazza bleeding index (BI). Two-level (patient and tooth) logistic regression models and three-level (patient, tooth, and site) linear regression models were constructed to analyze the influence of LA on PD for all teeth/sites and teeth/sites with an initial PD ≥ 5 mm. Decreases in PD and BI at sites under LA using the initial PD were also compared. RESULTS: A significantly higher mean decrease in PD after NSPT was found in the LA group than in the no local anesthesia (NLA) group (0.98 vs. 0.54 mm, t = 24.12, P < 0.001). A significantly higher probability of decreases was found in the LA group in BI (percentages of teeth with BI > 1 and BI > 2) for all teeth (16.7% vs. 13.8%, t = 3.75, P < 0.001; 34.7% vs. 28.1%, t = 6.73, P < 0.001) and PD for teeth with PD ≥ 5 mm (32.3% vs. 17.3%, t = 28.48, P < 0.001). The difference in PD between the LA and NLA groups increased as the initial PD increased. The difference between the two groups was 0.12 to 0.22 mm for sites with a baseline PD < 7 mm; however, it increased to 0.41 to 1.37 mm for sites with a baseline PD ≥ 7 mm. CONCLUSIONS: LA improved the decrease in PD after NSPT. Root debridement at sites with initial PD ≥ 7 mm should be performed under routine LA.

Influence of CYP1A1 rs1048943 on Short- and Long-term Outcomes of Non-surgical Periodontal Therapy for Generalised Aggressive Periodontitis.

Objective: To investigate the influence of CYP1A1 rs1048943 on short- and long-term outcomes of nonsurgical periodontal therapy (NSPT) for generalised aggressive periodon- titis (GAgP). Methods: The CYP1A1 rs1048943 polymorphisms of 224 GAgP patients were genotyped by time-of-flight mass spectrometry. A total of 125 patients received NSPT and subsequent followup for 3 months. Of the 125 patients, 81 were followed for at least 3 years. Clinical periodontal parameters were collected at baseline and at the follow-up visits. Negative binomial regression was used to analyse the association between the number of teeth lost during the 3-year observation period and CYP1A1 rs1048943 genotypes. Results: The mean probing depth (PD) and percentage of sites with Bleeding Index (BI) ≥ 3 were all significantly greater in CYP1A1 rs1048943 G allele carriers than non-carriers at 3 months and 3 years after treatment (P < 0.05). In the PD ≥ 7 mm subgroup, the mean PD was significantly higher in G allele carriers than non-carriers at the 3-year follow-up (P < 0.05). The other clinical parameters did not show a similar trend (P > 0.05). Furthermore, the changes of percentage of sites with BI ≥ 3 were significantly smaller in G allele carriers than non-carriers at 3 months and 3 years after treatment (P < 0.05). GAgP patients with the GG genotype had lost more over the 3-year follow-up period compared with patients with the AA genotype (P < 0.05). Conclusion: These data indicated that the CYP1A1 rs1048943 AG/GG genotypes may influence the short- and long-term outcomes of NSPT in GAgP patients.

Evaluation of Periodontal Status after Orthodontic Treatment: A Pilot Study on Patients with Stage IV/Grade C periodontitis.

OBJECTIVE: To evaluate whether the periodontal status was affected in patients with stage IV/grade C periodontitis after orthodontic treatment. METHODS: Twenty-four patients with stage IV/grade C periodontitis who received combined periodontal and orthodontic treatment were included in this study. Probing depth (PD), bleeding on probing (BOP) and percentage of relative bone height (RBH%) were measured and calculated. Parameter changes before and after orthodontic treatment, and their differences between teeth adjacent to extraction sites (TAES) and teeth nonadjacent to extraction sites (TNES) were compared. Three-level analysis was performed to test the influential factors of PD and RBH% reduction after orthodontic treatment. RESULTS: No change of PD, BOP% and RBH% was detected after orthodontic treatment. No difference of PD, BOP% and RBH% was detected between TAES and TNES. BOP negative, excessive horizontal overlap, excessive vertical overlap, crowding, PD at T0 (the last periodontal visit before orthodontic treatment) and RBH% at T0 were positively associated with PD reduction after orthodontic treatment. Being female, excessive horizontal overlap, excessive vertical overlap, crowding, PD at T0 and RBH% at T0 were positively associated with a RBH% reduction. Space was negatively associated with a RBH% reduction. CONCLUSION: Periodontal stability can be obtained for patients with stage IV/grade C periodontitis after orthodontic treatment. Orthodontic treatment with extraction was safe for patients with severe periodontitis, however, attention should be given to TAES.

Clinical performance of non-surgical periodontal therapy in a large Chinese population with generalized aggressive periodontitis.

AIM: This study aimed to evaluate clinical performance of non-surgical periodontal treatment (NSPT) and its influential factors in a large Chinese population with generalized aggressive periodontitis (GAgP). MATERIAL AND METHODS: Longitudinal periodontal examination data of 1,004 GAgP patients (numbers of patients with observation periods 6 weeks~, 3 months~, 6 months~, 1 year~, 3 years~ and >5 years were 203, 310, 193, 205, 70 and 23, respectively) were extracted from a hospital-based electronic periodontal charting record system and analysed by multilevel analysis. RESULTS: Mean probing depth (PD) and attachment loss (AL) reductions at patient level were 1.17 mm and 1.07 mm, respectively. Multilevel analysis demonstrated PD reductions after maintenance were mainly influenced by frequency of supportive periodontal treatment (FSPT), gender, adjunctive systemic use of antibiotics, baseline mobility, tooth type and baseline PD and bleeding index reductions were mainly influenced by FSPT, adjunctive systemic use of antibiotics, baseline AL, baseline mobility, tooth type and baseline PD. CONCLUSION: The clinical performance of NSPT on patients with GAgP was proved in the large Chinese population. Outcomes of NSPT were mainly influenced by FSPT, adjunctive systemic use of antibiotics, baseline mobility, tooth type and baseline PD.

Discrepancy of Clinical Parameters between the First and Second Molars Can Help to Differentiate Subjects with Aggressive Periodontitis from Chronic Periodontitis: a Cross-sectional Study Based on a Large Chinese Population.

OBJECTIVE: To explore associations between mean discrepancy values for the first and second molars (MDVFSs) and generalised aggressive periodontitis (GAgP) using hospital-based periodontal examination records from a large Chinese population. METHODS: Data from consecutive patients diagnosed as having chronic periodontitis (CP, n = 51,849) and GAgP (n = 2,706) were included. Patient ages, gender, smoking status, mean full-mouth probing depth (PD), and mean full-mouth attachment loss (AL), as well as MDVFSs for PD and AL, were extracted. Multivariate linear regression was used to test associations between MDVFSs and GAgP. RESULTS: After multivariate risk adjustment for potential confounding factors (age, smoking status, and mean PD and AL), the MDVFSs for PD (OR = 2.20, 95%CI: 2.04 to 2.38, P < 0.001) and AL (OR = 1.51, 95CI%: 1.44 to 1.59, P < 0.001) were significantly associated with GAgP. The probability of GAgP was associated with MDVFS for PD falling between 0 mm and 2.5 mm (OR = 4.55, 95%CI: 4.01 to 5.17) and MDVFS for AL falling between 0 mm and 3.5 mm (OR = 2.01, 95%CI: 1.86 to 2.16, P < 0.001). CONCLUSION: This study revealed associations between MDVFSs and GAgP, demonstrating that MDVFSs can serve as promising auxiliary references for the differential diagnosis between CP and GAgP.

Effectiveness of non-surgical periodontal therapy in a large Chinese population with chronic periodontitis.

AIM: The aim of this study was to evaluate the effectiveness of non-surgical periodontal treatment (NSPT) and its influential factors in a large Chinese population with chronic periodontitis. METHODS: Periodontal examination data of 10,789 patients with at least one periodontal re-evaluation record were extracted from a hospital-based electronic periodontal charting record system. Probing depth (PD) and bleeding index (BI) reductions after NSPT and their influential factors were analysed by multilevel analysis. RESULTS: Mean PD reductions at patient level and site level were 0.62 and 0.65 mm respectively. Mean reductions of percentage of tooth with BI > 1 and BI > 2 were 14.9% and 25.21%. Multilevel analysis demonstrated that PD and BI reductions were mainly influenced by baseline PD, baseline attachment loss (AL), baseline mobility, tooth type and frequency of periodontal maintenance (FPM). Besides, PD reduction was associated with baseline BI for all sites and was associated with gender and smoking status for sites with baseline PD ≥ 5 mm. CONCLUSION: The effectiveness of NSPT on patients with chronic periodontitis was proved in a large Chinese population. Outcomes of NSPT were mainly influenced by baseline PD, baseline AL, baseline mobility, tooth type and FPM.

[Association between FADS1 rs174537 polymorphism and serum proteins in patients with aggressive periodontitis].

OBJECTIVE: To investigate the potential association between FADS1 rs174537 polymorphism and serum proteins in patients with aggressive periodontitis, which may provide benefits for diagnosis and treatment of aggressive periodontitis. METHODS: A total of 353 patients with aggressive periodontitis (group AgP) and 125 matched controls (group HP) were recruited in the study. Genotyping of FADS1 rs174537 and serum biochemical indexes were tested at the study's start. The relationships between the levels of TP, GLB, ALB, A/G and genotyping were analyzed. RESULTS: (1) The detection rate of allele G in group AgP was higher than that in group HP(68.1% vs. 61.2%, P=0.046,OR=1.35,95% CI 1.00-1.83); the detection rate of genotype GG in group AgP was higher than in group HP(45.5% vs. 34.4%,P=0.029, OR=1.60, 95% CI 1.05-2.44). (2) In group AgP, the patients with GG genotype exhibited significantly lower TP, GLB than the patients with GT+TT genotype [(77.08 ± 7.88) g/L vs. (79.00 ± 4.66) g/L, P=0.007; (28.17 ± 7.63) g/L vs.(29.88 ± 3.49) g/L,P=0.007) and the higher A/G(1.72 ± 0.22 vs.1.67 ± 0.22, P=0.040), but there was no significant difference in ALB between the patients with GG genotype and the patients with GT+TT genotype. In group HP, there were no significant differences in TP, GLB, A/G and ALB between individuals with genotype GT+TT and with genotype GG. (3)Compared with individuals with genotype GT+TT in group HP, the AgP patients with genotype GT+TT exhibited significantly higher TP, GLB [(79.00 ± 4.66) g/L vs. (75.20 ± 4.53) g/L, P<0.01; (29.88 ± 3.49) g/L vs.(26.55 ± 2.94) g/L, P<0.01) and the lower A/G(1.67 ± 0.22 vs. 1.88 ± 0.30, P<0.01), but there was no significant difference in ALB. There were no significant differences in TP, GLB, A/G and ALB the between the AgP patients with genotype GG and the healthy subjects with the same genotype either. CONCLUSION: FADS1 rs174537 polymorphism is associated with aggressive periodontitis. The patients with genotype GG in group AgP had relatively lower TP,GLB and higher A/G. Genotype GG might be a risk indicator for aggressive periodontitis by reducing host defense capability and contributing to inflammatory response in the occurrence and development of aggressive periodontitis.

The Effects of Initial Periodontal Therapy on the Serum Receptor Activator of Nuclear Factor-κß Ligand/Osteoprotegerin System in Patients With Type 2 Diabetes Mellitus and Periodontitis.

BACKGROUND: The aim of the present study is to evaluate the serum receptor activator of nuclear factor-κß ligand (RANKL)/osteoprotegerin (OPG) system in patients with chronic periodontitis (CP) and type 2 diabetes mellitus (T2DM) and its changes after periodontal intervention. METHODS: Thirty-five patients with CP + T2DM, 35 systemically healthy patients with CP, and 35 healthy controls were enrolled, and serum levels of RANKL and OPG were measured at baseline. Then the CP + T2DM group was divided into a well-controlled subgroup and a poorly controlled subgroup according to their hemoglobin A1c (HbA1c), and initial periodontal therapy was performed. After 3 months, patients in both subgroups were recalled, and serum RANKL and OPG levels were tested again and compared with the baseline. RESULTS: At baseline, serum levels of OPG in the T2DM + CP group were much lower than in the CP group and healthy controls (197.41 ± 57.05 pg/mL versus 232.60 ± 70.85 pg/mL [CP group] or 244.96 ± 85.13 pg/mL [healthy controls], P <0.05), whereas their RANKL levels were much higher than in the other two groups (324.35 ± 87.62 pg/mL versus 284.52 ± 90.35 pg/mL [CP group] or 163.01 ± 45.24 pg/mL [healthy control], P <0.05), as was the RANKL/OPG (R/O) ratio (1.68 ± 0.33 versus 1.26 ± 0.35 [CP group] or 0.72 ± 0.25 [healthy control], P <0.001). Serum levels of OPG in both disease groups had significant negative correlations with HbA1C, and serum levels of RANKL in all participants had significant positive correlations with periodontal parameters. After periodontal intervention, both the well-controlled and poorly controlled subgroups exhibited significant increases in OPG and decreases in RANKL in serum, and the R/O ratio was also notably reduced. Additionally, the poorly controlled subgroup exhibited a greater reduction in HbA1c and a greater increase in OPG than the well-controlled subgroup. CONCLUSIONS: The changing trend in the serum RANKL/OPG system in patients with T2DM + CP was similar to that seen in CP patients and may be even more pronounced. Periodontal intervention effectively improved glucose metabolism and changed the serum RANKL/OPG system regardless of whether patients' HbA1c was well-controlled or poorly controlled over the 3-month observation period.

Perception of Non-surgical Periodontal Treatment in Individuals Receiving or Not Receiving Local Anaesthesia.

PURPOSE: Patients might refuse the offer of local anaesthesia (LA) administration prior to dental treatment. This study investigates subjective discomfort perception during non-surgical mechanical periodontal therapy delivered with or without LA. MATERIALS AND METHODS: Sixty patients with mild to moderate chronic periodontitis and prior periodontal debridement experience were randomly enrolled in nonsurgical therapy of a quadrant with or without LA administration. Patients were free to comply or not with the allocated LA arrangement. Visual analogue scales (VAS) of discomfort perception at various stages of the treatment as well as overall satisfaction were recorded. Demographic, psychosocial and periodontal parameters were recorded. RESULTS: Thirty-one patients undergoing nonsurgical periodontal therapy not receiving (LA-) and 29 participants receiving LA (LA+) were studied. Compared to LA- patients, LA+ individuals perceived less discomfort during treatment and reported less dental anxiety (p<0.05). Lower overall treatment satisfaction was associated with prior unpleasant periodontal experience (p=0.047). Overall, debridement discomfort was associated with not receiving LA, noncompliance with the pain control regimen allocated, longer treatment duration, greater gingival inflammation and a higher percentage sites with probing pocket depths≥5 mm (p<0.05). CONCLUSION: Clinicians should be aware that patients who refuse LA can experience higher dental anxiety and therefore may require various pain control strategies for comfort during nonsurgical periodontal therapy, which, if not employed, can lead to less periodontal treatment satisfaction.

[Analysis of serum IgG titers to Aggregatibacter actinomycetemcomitans serotype c in aggressive periodontitis patients].

OBJECTIVE: To analyze the serum IgG titers to Aggregatibacter actinomycetemcomitans(Aa) and associated factors in patients with aggressive periodontitis (AgP). METHODS: Venous blood samples were collected from 62 AgP patients and 45 periodontal healthy controls, unstimulated whole saliva and pooled subgingival plaque samples of AgP patients were also collected for the detection of Aa (PCR method). Serum IgG titers to Aa serotype c were measured by enzyme-linked immunosorbnent assay (ELISA). RESULTS: The detection rates of serum IgG to Aa serotype c in the AgP patients and the healthy controls were both 100%. The AgP patients exhibited significantly higher IgG titers to Aa serotype c than the healthy controls (11.1±1.9 vs. 9.1±1.8, P<0.01). There was no significant difference in serum IgG levels to Aa serotype c and in the prevalence of high-responding patients to Aa serotype c between the incisor-first molar type AgP patients and generalized AgP patients. Serum IgG titers to Aa serotype c in the Aa-positive AgP patients (the patients who were Aa-positive in subgingival plaque or saliva) were significantly higher than those of the Aa-negative patients (11.9±1.3 vs. 10.7±2.1, P<0.05). CONCLUSION: Serotype c was the main serotype of Aa in Chinese patients with AgP. Serum IgG responses in generalized AgP patients were comparable to those in incisor-first molar type AgP patients.

[Relationship between vitamin D receptor gene polymorphisms and chronic periodontitis].

OBJECTIVE: To investigate the relationship between vitamin D receptor (VDR) gene polymorphisms and chronic periodontitis(CP). METHODS: Buccal swabs from 105 patients with mild/mode-rate CP and 85 severe CP were collected, DNA was extracted from these buccal swabs using the TIANamp Swab DNA Kit [TIANGEN Biotech (Beijing) CO.Ltd]. The VDR rs1544410 and rs731236 were genotyped by the Sequenom MassARRAY system (Shanghai Benegene Biotechnology Co. Ltd), which was based on MALDI-TOF (matrix-assisted laser desorption ionization time-of-flight) technology. The distribution of the genotypes and allele frequencies were analyzed. RESULTS: The frequencies of the rs1544410 A allele and AA+AG genotype were significantly higher in severe CP than in mild/moderate CP of all the patients and the female patients respectively (all the patients: P=0.006, 0.007; the female patients: P=0.001, 0.001). The frequencies of the rs731236 C allele and CC+CT genotype were significantly higher in severe CP than in mild/moderate CP of all the patients and the female patients respectively (all the patients: P=0.003, 0.004; the female patients: P<0.001, <0.001). CONCLUSION: Gene polymorphisms of VDR rs731236 and rs1544410 may be associated with severe CP in Chinese Han population.

[Clinical and putative periodontal pathogens' features of different sites with probing depth reduction after non-surgical periodontal treatment of patients with aggressive periodontitis].

OBJECTIVE: To evaluate the differences of clinical parameters and putative periodontal pathogens in sites of different probing depth (PD) reduction after non-surgical periodontal treatment in patients with aggressive periodontitis (AgP). METHODS: Clinical examinations including plaque index, probing depth (PD), attachment level (AL) and bleeding index (BI), and full-mouth periapical photographs were collected from 20 patients with AgP. All the patients received non-surgical periodontal treatment, including oral hygiene instruction, supra-gingival scaling, subgingival scaling and root planing (SRP) and were followed up for 6 months post-therapy. Gingival crevicular fluids (GCF) were collected at 1 site in each quadrant before and at the end of 6 months post-therapy. Six kinds of putative periodontal pathogens and 6 kinds of short chain fatty acids (SCFAs) were detected in the GCF samples. RESULTS: The baseline clinical parameters of PD, AL and BI, the baseline concentration of succinic acid, acetic acid, propionic acid and butyric acid, and the prevalence of Treponema denticola were significantly higher in sites with PD reduction more than 2 mm sites compared with PD reduction no more than 2 mm sites [(7.7 ± 1.2) mm vs. (5.1 ± 1.8) mm, (6.3 ± 1.9) mm vs. (4.5 ± 2.2) mm, 3.8 ± 0.4 vs. 3.3 ± 0.8, 1.66 mmol/L vs. 1.10 mmol/L, 31.67 mmol/L vs.17.78 mmol/L, 3.31 mmol/L vs.1.95 mmol/L, 84.6% vs. 56.1%, P<0.05]. However, there were no significant differences in the clinical parameters, the 6 kinds of putative periodontal pathogen detection and SCFAs concentration between the 2 groups at the end of 6 months post-treatment. In sites with PD>5 mm at the end of 6 months post-therapy, all were found with red complex bacteria infection. CONCLUSION: The baseline clinical parameters are important factors in predicting PD reduction after non-surgical periodontal treatment in patients with AgP. In sites with deep pockets after non-surgical periodontal treatment, the active control of red complex bacteria is recommended.

[Determination of bone metabolic marker levels in perio-implant crevicular fluid and analysis of dental implants stability by resonance frequency in the early stage of healing].

OBJECTIVE: To investigate the changes of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) level in perio-implant crevicular fluid (PICF) and to monitor the development of the stability of Straumann® tissue-level implants by resonance frequency analysis (RFA) during the early phases of healing. METHODS: A total of 35 implants (length 10 mm) were placed. PICF samples were collected with filter paper strips at baseline, 1, 2, 3, 4, 6, 8, and 12 weeks post-surgery, respectively. The OPG, RANKL levels were determined by ELISA method. At the same time points, the implant stability quotient (ISQ) values were determined with Osstell™ mentor. RESULTS: During healing, PICF-OPG levels increased significantly 2 weeks after surgery when compared with the 4(th) -, 6(th) -, 8(th) - and 12(th) -week reevaluation (P<0.05). The OPG/RANKL ratio in PICF was significantly higher (P<0.05) than that in gingival crevicular fluid at 1 week post-surgery. ISQ slightly fluctuated within the first 4 weeks after installation. Following this, the ISQ values increased steadily for all the implants and up to 12 weeks. Significant differences were noted between the mean ISQ values at the 12th-week and other observation time points. CONCLUSION: The PICF-OPG levels may be effective in monitoring the process of osseointegration. All the ISQ values indicated the stability of Straumann® implants over a 12-week healing period. RFA is a reliable and effective assistant to monitor implant stability.

Association between plasma leptin level and systemic inflammatory markers in patients with aggressive periodontitis.

BACKGROUND: Increasing evidence supports an association between periodontitis and systemic diseases. Leptin is involved both in the energy metabolism and inflammatory processes and is suggested to be a link between periodontal infection and systemic health. The present study aimed to evaluate the peripheral leptin concentration in patients with aggressive periodontitis (AgP) and to explore the relationship between leptin and systemic inflammation. METHODS: Ninety patients with AgP visiting the Clinic of the Periodontology Department, Peking University School and Hospital of Stomatology between July 2001 and May 2006, and 44 healthy controls (staff and student volunteers in the same institute) were recruited. Plasma levels of leptin and inflammatory cytokines including interleukin (IL)-1ß, IL-6, tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were measured by enzyme-linked immunosorbent assay. Correlation and multiple linear regression analysis were performed to analyze the association between plasma leptin level and other variables. RESULTS: Plasma leptin level of AgP group was significantly higher than that of the control group (19.7 ± 4.4 ng/ml vs. 7.5 ± 1.3 ng/ml, P < 0.01). After controlling for age, gender, and body mass index, positive correlation was observed between plasma leptin concentration and log-transformed levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α and CRP), and the partial correlation coefficients ranged from 0.199 to 0.376 (P < 0.05). Log-transformed IL-1ß and IL-6 levels entered the final regression model (standardized ß were 0.422 and 0.461 respectively, P < 0.01). CONCLUSIONS: Elevated plasma leptin concentration may be associated with increased systemic levels of inflammatory markers in AgP patients.

[Isolation, culture and ultrastructure analysis of mesenchymal stem cells from human periodontal ligament].

OBJECTIVE: To isolate and culture human periodontal ligament stem cells (PDLSCs) and observe its ultrastructure. METHODS: The proliferation and growth characteristics of human periodontal ligament cells were observed in primary culture and colony culture. PDLSCs were isolated by magnetic activated cell sorting (MACS) and ultrastructural characterization was observed by electron microscopy. RESULTS: When the cells were cultured at low density, PDLSCs grew in a colony-like manner. With the exception of a small amount of rough endoplasmic reticulum, ribosomes, and mitochondria, relatively few organelles were found in the cytoplasm, suggesting that they had remained undifferentiated. CONCLUSION: PDLSCs showed colony-like growth capacity and had ultrastructural characterization with stem cells. This indicated that PDLSCs could act as the appropriate seed cells for cell-based periodontal tissue regeneration.

[Characteristic of sample banks isolated from EDTA-blood by sedimentation method].

OBJECTIVE: To assess the characteristics of establishing the different sample banks of plasma, leukocytes and DNA by sedimentation method of isolating from ethylene diamine tetraacetic acid(EDTA)-blood and to clarify the sedimentation method of leukocyte isolation and plasma volume by comparative data and recommended procedures for applicability. METHODS: In the study, 29 EDTA-bloods were obtained, the total amounts of leukocytes and the percentage of neutrophile granulocytes, and lymphocytes in the EDTA-blood detected as a control group and then assigned equally into 4 EP tubes with 1 mL EDTA-blood per tube as 4 test groups, then the 4 tubes were placed with the EDTA-blood at room temperature and the plasma layers were isolated at 0.5, 1, 2 and 3 h, receptively. The total amount of leukocytes and the percentage of neutrophile granulocytes, and lymphocytes were detected by automated hematology analyzer at the clinical laboratory. The volume of the plasma was also measured at the same time. RESULTS: The plasma volume at 0.5 h [(241.72 ± 101.52)µL] was substantially lower than those at 1 h[(317.24 ± 97.50)µL], at 2 h[(371.03 ± 91.66)µL], and at 3 h [(408.97 ± 97.43)µL] , P < 0.05. The plasma volume at 1 h was substantially lower than those at 2 h and 3 h (P < 0.05). The total amount of leukocytes in the plasma layer at 0.5 h (2.50 × 10(6) ± 1.48 × 10(6)) group was substantially higher than the amount of 2 or 3 h groups respectively (1.47 × 10(6) ± 7.19 × 105,1.21 × 10(6) ± 7.41 × 105), P < 0.05. Significant difference was not found between 0.5 h group and 1 h group (2.29 × 10(6)± 1.17 × 10(6)), P > 0.05. The total amount of leukocytes in the plasma layer in 1 h group was substantially higher than that in 2 h and 3 h groups (P < 0.05). There was no significant difference between 3 h group and 2 h group (P > 0.05). The total amount of leukocytes in the plasma layer of the 4 test groups was substantially lower than that in the control group (P < 0.05). The percentage of neutrophile granulocytes (54.14% ± 11.65%) in the plasma layer in 0.5 h group was substantially higher than those in 1 h, 2 h and 3 h groups (46.66% ± 12.70%,39.17% ± 12.33%,43.25% ± 14.54%), P < 0.05, respectively, which was the substantially lower than that in the control group (60.53% ± 8.46%), P < 0.05. The average value of the percentage of neutrophile granulocytes in the plasma layer in 1 h group was substantially higher than that in 2 h group (P < 0.05). There was no significant different between 3 h group and both 1 h, 2 h groups (P > 0.05). The mean percentage of lymphocytes in the plasma layer in 0.5 h group (35.09% ± 10.84%) was substantially lower than those in the plasma layer in 1 h, 2 h and 3 h groups, respectively ( 41.48% ± 12.20%, 47.96% ± 12.27%, 45.50% ± 13.71%), which was significant higher than that in the control group(30.98% ± 7.33%), P < 0.05. The average value of the percentage of lymphocytes in the plasma layer in 1 h group was substantially higher than those in the control group and 0.5 h group, but was substantially lower than those in 2 h and 3 h groups (P < 0.05). The average value of percentage of lymphocytes in the plasma layer in 2 h group was substantially higher than those in the control group, 0.5 h and 1 h groups (P < 0.05). There was no significant difference between 2 h and 3 h groups (P > 0.05). CONCLUSION: The best period of time in obtaining leukocytes is 0.5-1 h sedimentation of EDTA-blood. Both the plasma layer and leukocytes can be separated and obtained at the same time from the same sample by the sedimentation method of EDTA-blood. The sedimentation of EDTA-blood has the least interference of both chemical and physical factors, as well as a ready operation, which can establish the plasma, leukocytes and DNA sample banks for various aspects of research.

[Long-term clinical and hematologic effects of non-surgical treatment on aggressive periodontitis].

OBJECTIVE: To investigate the long-term effects of non-surgical treatment on clinical and hematologic states of patients with generalized aggressive periodontitis (GAgP). METHODS: Patients with GAgP (n = 25) and healthy controls (n = 28) were recruited. The clinical parameters, including probing depth (PD), bleeding index (BI), attachment loss (AL) were examined and recorded. Blood cell variables, including white blood cells (WBC), leukocyte, neutrophil, and lymphocyte counts, as well as serum triglycerides, fasting glucose and protein parameters, including total protein, albumin, globulin, and albumin/globulin ratio (A/G), were analyzed. Twenty-five GAgP patients received non-surgical treatment and the clinical and blood parameters 3 to 7 years after treatment were re-evaluated. Clinical and hematological parameters of the two groups were compared. Comparisons of clinical and hematologic parameters pre- and post-treatment in GAgP group were performed through one-way ANOVA and paired-t test. RESULTS: Elevated white blood cells, neutrophil numbers and serum total protein, globulin levels were observed in patients with GAgP compared to controls[(6.3 ± 2.0)×10(9)cell/L vs.(5.4 ± 1.0)×10(9)cell/L, (4.1 ± 1.8)×10(9) cell/L vs.(3.0 ± 0.9)×10(9) cell/L, (78.2 ± 4.4) g/L vs. (75.6 ± 4.6) g/L and (29.3 ± 3.8) g/L vs.(26.5 ± 3.9) g/L respectively, P < 0.05]. A/G ratio was lower in the GAgP group than in the control group (1.7 ± 0.2 vs.1.9 ± 0.3, P < 0.01). Three to seven years after periodontal treatment, the reduction of PD and BI was observed in GAgP group(P < 0.05). There were significant decreases of WBC count, neutrophil count, serum total protein and globulin level, and significant increases of albumin level and A/G at 3 to 7 years after treatment(P < 0.05). CONCLUSIONS: Non-surgical treatment may have long-term beneficial effect on the periodontal clinical status and hematologic parameters of generalized aggressive periodontitis.

[The accuracy of probing depth measurements of undergraduate students and associated factors analysis].

OBJECTIVE: To investigate the accuracy of probing depth measurements of undergraduate students in department of periodontology and analyze the cause of measurement errors. METHODS: Thirty-eight dental students from Peking Universty School and Hospital of Stomatology who began their periodontal clinical practice for the first time were recruited. According to principle of clinical teaching, after the students recorded the probing depth of 1-2 periodontitis patients using Williams periodontol probe, an experienced teacher checked the probing depth. The measurements of interproximal sites of Ramfjord index teeth (6 14 41 6) were used as the data of this study. According to the probing depth discrepancies between teacher and the students, all the probing sites were divided in three levels: absolutely consistent sites (probing depth measured by teacher and by student was completely consistent), almost consistent sites (the depth discrepancy between teacher and student was 1 mm), inconsistent sites (the depth discrepancies between teacher and student ≥ 2 mm). RESULTS: The accuracy of probing depth measurements of students decreased with the deepening of probing depth, and the accuracy of probing depth measurements in molar teeth was significantly lower than incisor teeth [58.8% (261/444) vs.73.1% (339/464), P < 0.01]. The main factor associated with the accuracy of probing depth measurements in interproximal sites was the probe's inability to get into gingival col, which accounted for 70.7% (87/123) of the total inconsistent sites. CONCLUSIONS: The correct angle of insertion of the probe in interproximal sites should be reinforced during the course of pre-clinical education of periodontal probing. More attention should be paid to check the probing depth of deep pockets and molar teeth during the clinical practice of undergraduate students.