Objective:To analyze the histopathological characteristics of peri-implant soft tissue in re-constructed jaws and the changes after keratinized mucosa augmentation(KM A)with free gingival graft(FGG).Methods:Twenty patients were enrolled in this study.Five patients of them,who were perio-dontal and systemic healthy and referred for crown lengthening before restoration with healthy keratinized gingiva collected were enrolled as healthy controls.15 patients of them were with fibula or iliac bone flaps jaw reconstruction(10 with fibula flap and 5 with iliac flap),who were referred to FGG and implant exposures before restoration.Soft tissue was collected before FGG in reconstructed jaws,and in 5 patients(3 with fibula flap and 2 with iliac flap)8 weeks after FGG if a second surgery was conducted.Histologi-cal analysis with hematoxylin-eosin stain and immunological analysis to interlukin-1(IL-1),interlukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were performed.Results:Thickness from the bottom of stratum basale to the top of stratum granulosum and thickness of keratinized layer in reconstructed jaws were significantly lower compared with that of natural healthy keratinized gingiva[0.27(0.20,0.30)mmvs.0.36(0.35,0.47)mm,P＜0.05;16.49(14.90,23.37)μm vs.26.37(24.12,31.53)μm,P＜0.05].In the reconstructed area,thickness from the bottom of stratum basale to the top of stra-tum granulosum increased after KMA with FGG[0.19(0.16,0.25)mm vs.0.38(0.25,0.39)mm,P=0.059]and the thickness of keratinized layer significantly increased after KMA with FGG[16.42(14.16,22.35)μm vs.28.57(27.16,29.14)μm,P＜0.05],which was similar to that in the con-trol group.Furthermore,the number of positive cells of IL-1,IL-6 and TNF-α significantly increased after KMA[0.67(0.17,8.93)vs.11.00(9.16,18.00);13.00(8.50,14.14)vs.21.89(15.00,28.12);0.22(0.04,0.63)vs.2.83(1.68,5.00),respectively,P＜0.05]as well as the average optical density value[0.15(0.14,0.17)vs.0.18(0.17,0.21);0.28(0.26,0.33)vs.0.36(0.33,0.37);0.23(0.22,0.29)vs.0.30(0.28,0.42),respectively,P＜0.05],which was similar to that in the healthy keratinized gingiva.Conclusion:The lack of rete pegs and inflammato-ry factors were common in soft tissue with jaw reconstruction.FGG can improve the quality of the epithe-lium and may improve the stability of the mucosa around implants.

Objective:To analyze the concentration of formic acid,propionic acid and butyric acid in gingival crevicular fluid(GCF)of patients with stages Ⅲ and Ⅳ periodontitis,and their relationship with periodontitis.Methods:The study enrolled 37 systemically healthy patients with periodontitis and 19 healthy controls who visited Department of Periodontology,Peking University School and Hospital of Sto-matology from February 2008 to May 2011.Their GCFs were collected from the mesial-buccal site of one molar or incisor in each quadrant.Periodontal clinical parameters,including plaque index(PLI),probing depth(PD),bleeding index(BI),and attachment loss(AL).Concentrations of formic acid,propionic acid and butyric acid in the supernatant of the GCFs were analyzed by high-performance capil-lary electrophoresis(HPCE).The prediction ability of formic acid,propionic acid and butyric acid with the risk of periodontitis and the differences between grade B and grade C periodontitis were analyzed.Results:In this study,32 patients with stage Ⅲ and 5 patients with stage Ⅳ were enrolled,including 9 patients with grade B and 28 patients with grade C.Clinical periodontal variables in the patients with pe-riodontitis were significantly higher than those in the control group(P＜0.001).Formic acid was signifi-cantly lower in periodontitis than that in the control group[5.37(3.39,8.49)mmol/L vs.12.29(8.35,16.57)mmol/L,P＜0.001].Propionic acid and butyric acid in periodontitis were significantly higher than those in the control group:Propionic acid,10.23(4.28,14.90)mmol/L vs.2.71(0.00,4.25)mmol/L,P＜0.001;butyric acid,2.63(0.47,3.81)mmol/L vs.0.00(0.00,0.24)mmol/L,P＜0.001.There was no significant difference in formic acid,propionic acid and butyric acid concentrations between grade B and grade C periodontitis(P＞0.05).Propionic acid and butyric acid in the deep pocket were significantly higher than in the shallow pocket,while the concentration of formic acid decreased with the increase of PD.Propionic acid(OR=1.51,95％CI:1.29-1.75)and butyric acid(OR=3.72,95％CI:1.93-7.17)were risk factors for periodontitis,while formic acid(OR=0.87,95％CI:0.81-0.93)might be a protective factor for periodontitis.Propionic acid(AUC=0.852,95％CI:0.805-0.900),butyric acid(AUC=0.889,95％CI:0.841-0.937),f(formic acid,AUC=0.844,95％CI:0.793-0.895)demonstrated a good predictive capacity for the risk of periodontitis.Conclusion:The concentration of formic acid decrease in the GCF of periodontitis patients,which is a protective factor for periodontitis,its reciprocal have good predictive capacity.However,propionic acid and butyric acid increase,which are risk factors for periodontitis and have good predictive capacity.The concentration of formic acid,propionic acid,and butyric acid vary with probing depth,but there is no significant difference between grade B and grade C periodontitis.

The S3 level clinical practice guideline for the prevention and treatment of peri-implant diseases, developed by the European Federation of Periodontology, was published in June, 2023 (DOI: 10.1111/jcpe.13823), which culminated in the recommendations for implementation of various different interventions before, during and after implant placement/loading. Aim of the present article is to summarize and interpret the key points of this guideline and help clinicians understand this guideline better, in order to standardize the prevention and treatment of peri-implant diseases.

Objective　It is important to distinguish between motor and sensory fascicles of the peripheral nerves for nerve alignment in surgery.No biomarkers currently are available for identification of motor or sensory fascicles.The objective of this study is to search the specific proteins between sensory and motor fascicles of peripheral nerves and provide biomarkers for the identification of functional fascicles of peripheral nerves.Methods　The normal state of motor branch and saphenous nerve of femoral nerve in Wistar rats,and at 8 hours and 8 days after Sunderland V injury were respectively sampled.Five mm long samples were taken from the distal side of the broken end,and a total of 18 groups of proteins were isolated from 6 samples.After purification and quantification,differential gel electrophoresis (DIGE) was used to label the proteins,gel image was scanned,and image analysis software (DeCyder) was used to compare and identify the differentially expressed proteins in each group.Protein spots with more than 1.5 times of difference in expression were selected to prepare glue-cutting,enzyme-cutting and spot target.PMF chromatogram was analyzed and identified by MALDI-TOF-PRO mass spectrometer,and the results of proteomics were analyzed and compared by RT-PCR.Chi-square tests and t-tests were performed for comparison between motor or sensory nerve groups.Results　The data identified 6 proteins that were differentially expressed between motor and sensory fascicles (>1.5-fold,P<0.05),including Annexin V,neurofilament light polypepticle,TEC kinase,serine protease inhibitor A3N,Peroxiredoxin-2,and TPM1.The proteomic results were consistent with the mRNA expression levels of these genes as determined by quantitative reverse transcription polymerase chain reaction.Conclusion　There were significant differences in proteomic expression between the peripheral sensory and motor fascicles,and Annexin V can be used as a high-difference marker protein to distinguish the peripheral sensory from motor fascicles.

Non-surgical periodontal treatment (NSPT) is the most essential part of periodontal treatment. Most patients with periodontitis and type 2 diabetes mellitus (T2DM) can achieve a satisfying outcome by NSPT. For these patients, NSPT can not only improve clinical periodontal parameters significantly and decrease the serum inflammatory status,but also improve glucose and lipid metabolism to some extent. Thus, NSPT is of great significance in preventing or retarding the progress of T2DM or even its complications. However, the special general condition of T2DM makes NSPT effects on periodontitis patients partially differ from those without systemic diseases. Therefore, the special characteristic led by T2DM should be taken into account in the decision and implementation of treatment plans for periodontitis patients. This paper will review the above issues mainly based on the studies of our research group.

The prevalence and mortality of the patients who suffer cardiovascular and cerebrovascular diseases are rising in China, and the number of periodontitis patients with cardiovascular and cerebrovascular diseases is growing. Certain principles should be followed during periodontal treatments for these patients due to their particular health conditions. Stomatologists should cooperate with cardiovascular physicians to evaluate the risks and benefits of periodontal treatments in advance, and to select reasonable treatment timings and plans. During treatments, the heart rates, blood pressures and other vital indicators are monitored in real time to avoid acute cardiovascular and cerebrovascular events. The application, discontinuation and adjustment of specific cardiovascular drugs are determined by cardiovascular physicians.

Objective:To analyze the influences of leukocytes on improving blood glucose control in patients with type 2 diabetes mellitus (T2DM) and periodontitis after periodontal mechanical therapy.Methods:Thirty-five patients visiting Peking University Third Hospital from March 2011 to August 2012, as well as thirty-four patients visiting Peking University School and Hospital of Stomatology from March 2011 to August 2012 and December 2016 to December 2018 were selected in this research. These subjects were non-smokers, and with moderate to severe chronic periodontitis and T2DM. The full set of periodontal examinations including probing depth (PD), attachment loss (AL), bleeding index (BI) and plaque index (PLI) were conducted. Besides, counts of white blood cells (WBC), parameters of glucose and lipids metabolites such as fasting blood glucose (FBG), glycosylated hemoglobin (HbA 1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) in serum were examined before treatment. Then, oral hygiene instruction, scaling and root planing (SRP) were carried out. Three months after SRP, the baseline examinations were repeated in all patients. According to the baseline leukocyte counts, the patients were divided into subgroups: low WBC group (WBC<6.19×10 9/L) and high WBC group (WBC≥6.19×10 9/L). Paired t-test for comparison of changes after treatment, analysis of co-variance for comparing the intervention effects between subgroups, and multifactor Logistic regression analysis were performed. Results:Three months after SRP, all periodontal indexes were significantly improved in both groups. Leukocyte counts decreased significantly in high WBC group (6.89±1.53 vs. 7.64±1.51, P=0.008). In high WBC group, HbA 1c (7.18±1.09 vs. 7.67±1.35, P=0.001) and LDL (2.67±0.85 vs. 3.28±0.76, P=0.042) decreased significantly, while there were no such differences in low WBC group. Influence of leukocyte level on HbA 1c ( OR=0.12, P=0.038) and LDL ( OR=0.15, P=0.001) improvement was statistically significant. Hierarchical analysis showed such improvement notably perform in female [HbA 1c ( OR=0.30, P=0.021), LDL ( OR=0.34, P=0.001)] and severe periodontitis group [HbA 1c ( OR=0.15, P=0.025), LDL ( OR=0.24, P=0.017)]. Through interaction test, female and leukocyte counts at baseline had relative excess risk affecting the effect of periodontal intervention on HbA 1c ( P=0.036) and LDL ( P=0.005). Conclusions:SRP could significantly improve the blood glucose and lipid control in patients who had T2DM and chronic periodontitis with relative higher leukocytes level. Female patients with severe periodontitis showed more obviously effects.

Objective:To investigate the prevalence of five specific periodontal pathogens in the saliva of edentulous patients and to compare the differences in the saliva of dentulous individuals with various periodontal conditions.Methods:All the subjects were patients who received regular care at the Beijing Hypertension Prevention and Management Institute. Twenty-seven edentulous patients (edentulous group) were included. According to age (age gap≤5 years), gender, smoking status, diabetes status and hypertension status, each edentulous patient was paired with dentulous individuals suffering from various severity of periodontitis in the same cohort. Then, we selected 3 groups of patients ( n=27 in each group) with no or mild periodontitis (mild group), moderate periodontitis (moderate group) and severe periodontitis (severe group). The whole unstimulated saliva was collected before the periodontal examination. Questionnaire survey and periodontal parameters, including plaque index (PLI), probing depth (PD), bleeding index (BI) and clinical attachment loss (CAL), were examined at mesial-buccal and distal-lingual sites of each tooth respectively. DNA was extracted from each sample of the salivary deposition. Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Campylobacter rectus (Cr) and Prevotella nigrescens (Pn) were detected by using PCR method based on 16SrRNA. The prevalence and quantity of the pathogens under various severity of periodontitis were compared. Results:One or more periodontal pathogens could be detected from the 78% (21/27) of the salivary samples in edentulous group. Thereinto, the prevalences of the five periodontal pathogens were ranked as (from high to low): Cr [56% (15/27)], Tf [44% (12/27)], Pn [26% (7/27)], Pg [22% (6/27)] and Td [11% (3/27)]. All five pathogens′ prevalences and Pg, Tf, Td and Pn′s quantities showed statistical differences among the four groups. The numbers of detected bacterial species in the mild, moderate and severe groups were significantly higher than that in the edentulous group ( P<0.01). Furthermore, the prevalences of the red complex in three dentulous groups [96% (26/27) in each group] were significantly higher than the edentulous group [48% (13/27)] ( P<0.05). The proportions of the red complex among all five pathogens (83%) in moderate and severe groups were significantly higher than that in the edentulous group (37%) ( P<0.01). Conclusions:All five periodontal pathogens could be detected in most of the saliva samples from edentulous individuals. Nevertheless, the prevalence and quantity were lower than dentulous individuals.

Objective: To investigate the influential factors related to the long-term effect of periodontal-orthodontic treatment in patients with aggressive periodontitis (AgP). Methods: A retrospective analysis was conducted in 25 AgP patients, who have received periodontal-orthodontic treatment in Peking University School and Hospital of Stomatology. Changes in the ratio of the residual alveolar bone height (RBH) was measured at three time points: baseline (T0), post orthodontic treatment (T1), and the last re-visit 3 years after orthodontic treatment (T2). Root abnormity was evaluated by observing periapical radiographs, and its relationship with alveolar bone loss after orthodontic treatment was analyzed. A multi-level analysis on factors related to the clinical outcome (alveolar bone height change) was performed. Results: Totally 693 teeth of 25 patients at T0 and T1 and 368 teeth of 14 patients at T2 were investigated. During the periodontal-orthodontic treatment, the RBH was mainly influenced by root abnormity (estimation value −2.392), tooth position (estimation value for upper teeth vs. lower teeth 3.139, and anterior teeth vs. posterior teeth −3.469) and the baseline RBH at T0 (estimation value −0.391) (P<0.05). Teeth with root abnormity, teeth in mandibular and anterior area, and teeth with higher RBH showed less change in T1-T0 RBH values. In the long-term follow-up, RBH was mainly influenced by tooth position (estimation value for upper teeth vs. lower teeth 3.735, and anterior teeth vs. posterior teeth −5.318), the baseline RBH and probing depth (PD) at T0. Teeth in mandibular and anterior area, teeth with higher RBH (estimation value -0.498) and PD (estimation value -1.594) (P<0.05) showed less change in T0-T2 RBH values. Conclusions During orthodontic treatment, teeth with abnormal root, lower teeth, anterior teeth, and teeth with high RBH were unfavorable factors for bone gain. In the long-term observation, lower teeth, anterior teeth, teeth with high RBH and PD at first visit were unfavorable factors for bone gain.