Multifactorial analysis of factors influencing premolar mobility in stage III/IV grade C periodontitis patients ≤ 35 years of age: a cross-sectional study.

BACKGROUND: Previous studies have suggested a potential link between the crown-to-root ratio (CRR) and root morphology in patients with mild chronic periodontitis, which may be associated with tooth mobility. However, these findings have not been thoroughly investigated. Our previous study found that 76% of patients with aggressive periodontitis, particularly those with premolar involvement, exhibited abnormal root morphology, severe alveolar bone loss, and increased tooth mobility, leading to poor clinical outcomes. This study aims to investigate the specific correlations among alveolar bone resorption, root morphology, CRR, and periodontal clinical indicators with premolar mobility in stage III/IV grade C periodontitis patients aged ≤ 35 years. MATERIALS AND METHODS: A total of 1,064 premolars from 151 stage III/IV grade C periodontitis patients aged ≤ 35 years were included in the study. Clinical periodontal parameters and radiographic measurements were recorded. Logistic regression analysis was used to explore the relationships between these indicators and tooth mobility. RESULTS: Significant variations in premolar root lengths were observed, ranging from 6.80 mm to 20.96 mm. Teeth with shorter roots (mean length: 10.22 mm) exhibited grade I mobility with only 28% alveolar bone resorption, whereas those with medium-length (mean length: 12.67 mm) and longer roots (mean length: 14.91 mm) exhibited mobility at 34% and 37% bone resorption, respectively. Regression models incorporating the bone-level CRR, average probing depth, and root length demonstrated strong predictive accuracy for tooth mobility (P < 0.001, AIC = 1700.574). CONCLUSION: Premolar mobility is influenced by variations in root length, alveolar bone resorption, and probing depth. The bone-level CRR is an effective predictor for assessing tooth mobility, especially when there are differences in root length and alveolar bone resorption.

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.

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.

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.

[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.

[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.

[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.

[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.

[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.

Association of crown-root ratio and tooth survival in Chinese patients with advanced periodontitis: An 11-year retrospective cohort study.

INTRODUCTION: Periodontitis is a chronic multifactorial inflammatory disease which eventually lead to tooth loss (TL). Therefore, a retrospective study was conducted to evaluate the status of tooth survival within 11 years after non-surgical periodontal treatment (NSPT) and to analyze the risk factors especially crown-root ratio (CRR) that affected TL in Chinese with advanced periodontitis. METHODS: 3481 teeth of 131 subjects who underwent NSPT were examined retrospectively within a mean follow-up period of 11.6 years. The association of risk factors including clinical and radiographic parameters with TL was assessed using univariate and multivariate Cox regression analyses. Smooth curve fitting and segmented regression model were conducted to show the nonlinear relationship and the threshold effect between CRR and the risk of TL. RESULTS: 347 teeth were lost in 97 patients in this study. Male, diabetes mellitus, heavy-smoker, molar, probing depth (PD), attachment loss (AL), bleeding on probing (BOP), tooth mobility, and radiographic bone loss were significantly associated with tooth loss (P < 0.05). A nonlinear relationship between CRR and the risk of TL was found, with different turning point values between molars and non-molars (1.9 vs. 2.76). CONCLUSIONS: The findings based on practice-based clinical and radiographic data do suggest a nonlinear relationship between CRR and the survival of teeth, and provide evidence to help clinicians to determine the prognosis of teeth for patients with advanced periodontitis. CLINICAL SIGNIFICANCE: Based on clinical and radiographic data, this study provides an individualized basis for clinicians to judge the dental prognosis of patients with advanced periodontitis according to the different tooth sites.

[Effect of recombinant human S100A8 on the proliferation and migration of periodontal ligament cells].

OBJECTIVE: To investigate the effect of S100A8 on the proliferation and migration of periodontal ligament cells (PDLCs), and to learn the role of S100A8 in the development of periodontitis. METHODS: PDLCs were treated with S100A8 in vitro before MTT and flow cytometry assays were performed. Transwell assay and wound assay were conducted to test the migratory activity of the PDLCs as well. RESULTS: In the study, 10⁻7-10⁻5 mol/L recombined human S100A8 suppressed the proliferation of the PDLCs, while their proliferation was significantly inhibited with 10⁻5 mol/L S100A8 treatment for 48 h. And 10⁻9-10⁻7 mol/L S100A8 enhanced the migratory activity of the PDLCs while the effect of 10⁻9 mol/L S100A8 was statistically significant. CONCLUSION: Increased level of S100A8 in periodontitis could lead to the inhibition of cell proliferation and apoptosis of PDLCs, but S100A8 could promote the migration of PDLCs when its concentration decreased after treatment.

[Relationship between volatile fatty acids and Porphyromonas gingivalis and Treponema denticola in gingival crevicular fluids of patients with aggressive periodontitis].

OBJECTIVE: Short chain fatty acids (SCFAs), such as succinic acid, acetic acid, propionic acid, butyric acid, etc. are metabolic product of putative periodontal pathogens, which play significant roles in periodontitis. The aim of this study was to analyze the relationship between Porphyromonas gingivalis (P. gingivalis), Treponema denticola (T. denticola), and the concentration of SCFAs in gingival crevicular fluid (GCF) of patients with aggressive periodontitis (AgP). METHODS: GCF was sampled from 4 sites per individual in 20 patients with AgP and 14 healthy controls. Concentrations of SCFAs, including succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid in the supernant of GCF were analyzed by high performance capillary electrophoresis (HPCE), P. gingivalis and T. denticola in the deposit of the same GCF were detected by PCR with their electrophoretic band quantified. RESULTS: The concentrations of succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid, the prevalence and PCR band quantity of P. gingivalis and T. denticola in GCF were all significantly higher in patients with AgP than that of healthy controls. In patients with AgP, butyric acid concentration was significantly higher in P. gingivalis positive sites than negative sites [2.87 (0.99, 4.36) mmol/L vs. 0.33 (0.00, 1.44) mmol/L, P<0.05], the concentrations of succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid were positively correlated with PCR band quantity of P. gingivalis (r value was 0.334, 0.548, 0.411, 0.493, 0.273, respectively, P<0.05); the concentrations of SCFAs were significantly higher in T. denticola positive sites than negative sites: succinic acid, 1.67 (1.15, 2.11) mmol/L vs. 0.80 (0.48, 1.06) mmol/L; acetic acid, 31.95 (23.77, 43.13) mmol/L vs.12.51 (7.57, 15.69) mmol/L; propionic acid, 11.86 (6.55, 14.98) mmol/L vs. 2.82 (1.71, 7.03) mmol/L; butyric acid, 3.45 (2.41, 4.78) mmol/L vs. 0.54 (0.00, 1.56) mmol/L; isovaleric acid, 2.23 (1.05, 3.85) mmol/L vs. 0.62 (0.00, 2.33) mmol/L. The concentrations of succinic acid, acetic acid, propionic acid, butyric acid were positively correlated with PCR band quantity of T. denticola (r value was 0.443, 0.702, 0.625, 0.557, respectively, P<0.05). CONCLUSION: SCFAs concentrations reflect the quantity of P. gingivalis and T. denticola in patients with AgP, and may be an indicator to the disease progression in patients with AgP.

[Effect of periodontal therapy on metabolic control and serum biochemical markers in subjects with type 2 diabetes and chronic periodontitis].

OBJECTIVE: To investigate the effect of periodontal therapy on periodontal clinical index, metabolic control and serum biochemical markers in subjects with type 2 diabetes and chronic periodontitis comprehensively. METHODS: Forty patients with type 2 diabetes and chronic periodontitis were enrolled, and periodontal clinical parameters, HbA1c, fasting blood glucose (FBG) and serum biochemical markers were tested at baseline and 3 months after initial periodontal therapy. RESULTS: The periodontal clinical parameters (PLI, BI,PD,CAL and BOP) improved significantly 3 months after initial periodontal therapy (P<0.001). The HbA1c also decreased statistically (P=0.014), while there was no change in venous fasting blood glucose. Other serum biochemical markers changed significantly including serum phosphor increased, calcium-phosphorus ratio decreased, triglyceride decreased, Apo A1 increased, lipoprotein a decreased, and serum total bilirubin increased. CONCLUSION: The initial periodontal therapy can significantly improve periodontal clinical parameters and HbA1c control, but the effect on venous fasting blood glucose was not revealed yet. In addition, initial periodontal therapy can also intervene serum phosphorus,calcium-phosphorus ratio, and the metabolism of lipid.

[Predictive model for post-treatment tooth loss of patients with aggressive periodontitis].

OBJECTIVE: To establish a predictive model for long-term tooth loss of patients with aggressive periodontitis (AgP) after periodontal treatment. METHODS: Patients diagnosed as AgP in Department of Periodontology, Peking University School and Hospital of Stomatology, who were re-evaluated 3 to 11 years after periodontal treatment were enrolled (n=85). Logistic regression was performed to select background, periodontal and radiographic factors which were related to long-term post-treatment tooth loss. A predictive model was built and analyzed by receiver operator characteristic (ROC) curve. RESULTS: After periodontal treatment, 55 teeth from 22 patients lost further. High prevalence of baseline bone loss, root abnormality, and residual severe bleeding sites, as well as poor compliance to maintenance were detected as risk factors in the predictive model. ROC analysis found the sensitivity and specificity of the model could reach up to 80% simultaneously. CONCLUSION: Predictive model for post-treatment tooth loss of patients with AgP is an important adjunct in clinical practice.

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.

[Screening and structure analysis of the aptamers against human recombinant S100A8 protein].

OBJECTIVE: To obtain and characterize the single-stranded DNA (ssDNA) aptamers of human recombinant S100A8 protein. METHODS: According to systematic evolution of ligands by exponential enrichment (SELEX) method, an ssDNA random library was subjected to 11 rounds of selection against human recombinant S100A8 protein. Using a biotin-strepavidin-HRP detecting system, the binding capacity of ssDNA to targeted protein from each round was monitored, until the binding level reached a saturation state. Then the ssDNA from the last cycle were cloned and sequenced, and the sequences were further analyzed by programs of bioinformatics. RESULTS: After 11 cycles of selection, 30 clones were selected randomly and sent to sequence analysis. A unique conserved sequence was not obtained among the 30 aptamers by the primary structure analysis, but three aptamers were found identical with three other aptamers respectively. The secondary structure analysis revealed that stem-loop and pocket were the main motifs, indicating that they may play a key role in the binding of aptamers to human recombinant S100A8 protein. According to the ratio of stem-loop to pocket, 30 aptamers were divided into 4 groups, and the affinity of aptamer No. 35 from group I was the highest. CONCLUSION: Aptamers against human recombinant S100A8 protein were identified by SELEX method, which laid the basis for the further application of the aptamers and the function study of human recombinant S100A8 protein.

[Clinical evaluation of periodontal intrabony defects treated with a reconstituted bovine porous bone mineral containing bone morphogenetic proteins].

OBJECTIVE: To compare the outcomes of bovine porous bone mineral (BPBM) containing bone morphogenetic proteins (BMP) and BPBM alone in periodontal intra-bony defects. METHODS: In the study, 22 intrabony defects of 9 patients with periodontitis were recruited. All the patients had at least one pair of intrabony defects of ≥3 mm. The split-mouth and single blind methods were used. The defects were randomly assigned to BPBM containing BMP (test) or BPBM alone (control). After debridement, the intrabony defects were treated by bone graft. Assessments at baseline and after 6 months included plaque index, attachment level, probing pocket depth, bleeding indexes on probing and gingival recession. The early wound-healing, adverse effects and patients' perceptions were also recorded. RESULTS: The gain in clinical attachment was (3.0±1.2) mm in the test group and (3.2±1.1) mm in the control group. The pocket reduction was (3.4±1.5) mm in the test group and (2.8±1.0) mm in the control group. The reduction of bleeding index was 1.9±1.3 in the test group and 2.3±0.8 in the control group. There was no statistical difference between the test group and control group (P>0.05). CONCLUSION: Both treatment modalities led to similar significant clinical improvements.

[Effects of emdogain on human periodontal ligament cells in vitro].

OBJECTIVE: To investigate the effects of emdogain, enamel matrix derivative (EMD), on the proliferation, cell cycle, mineralization and ultrastructure of human periodontal ligament (PDL) cells in vitro. METHODS: The influence of cell growth on PDL cells was evaluated by Cell Counting Kit-8 (CCK-8) in the presence and absence of emdogain, after 1, 3, and 5 d of culture. DNA synthesis and ultrastructure of PDL cells were observed by flow cytometry(FCM) and transmission electron microscopy (TEM) in the presence and absence of emdogain after 3 d of culture. The increasing of osteogenic capacity was verified by the expression changes of osteogenic differentiation markers of bone sialoprotein (BSP) and osteopontin (OPN) in emdogain-treated PDL cells by immunohistochemicl staining. RESULTS: Incubation of PDL cells with emdogain after 3 d significantly stimulated cell growth and DNA synthesis. Emdogain enhanced the osteogenic potential of PDL cells by high expression of osteogenic differentiation markers of BSP and OPN. CONCLUSION: The data indicate that Emdogain enhances cell proliferation and promotes differentiation of PDL cells, which contributes to periodontal tissue regeneration .