[Comparison of clinical effects between periodontal endoscopy aiding subgingival debridement and flap surgery].

OBJECTIVE: To compare the clinical effects of periodontal endoscopy aiding subgingival debridement with periodontal flap surgery on residual deep pockets of chronic periodontitis. METHODS: In the single-blind randomized control clinical study, residual deep pockets of periodontitis patients were still existing when re-evaluation after receiving initial periodontal treatment.The pockets which were necessary for bone surgery or guided tissue regeneration surgery were excluded.The sites were divided into test group and control group randomly.Test group sites underwent periodontal endoscopy aiding debridement and control group sites had periodontal flap surgery.At the baseline and 3 months later, parameters, such as plaque index (PLI), bleeding index (BI), probing depth (PD), attachment loss (AL) were examined.Bone height was measured by parallelly digital X-ray dental film.Meanwhile, treatment time and comfort scale (visual analogue scale, VAS) were also recorded. RESULTS: At baseline, 41 proximal sites with residual deep pockets were enrolled (test sites=21, control sites=20).All the parameters were not significantly different between the two groups.PD decreased by (1.67±0.91) mm from (5.62±0.86) mm to (3.95±0.74) mm in test group and by (2.25±1.12) mm from (5.95±1.19) mm to (3.70±0.73) mm in control group significantly (P < 0.05).The difference between the two groups was not significant.The PD of all the sites decreased lower than 5 mm, meanwhile, 76% was lower than 4 mm in test group and 85% was lower than 4 mm in control group.The BI decreased by 0.81±0.93 in test group and 0.65±0.99 in control group significantly (P < 0.05).The difference between the two groups was not significant.The PLI showed a tendency of decrease more in test group and bone height showed a trend of decrease more in control group, however, the difference was not significant.The treatment time was almost the same.The patients felt more comfortable in the test group (VAS was 0.60±0.89) than the control group (VAS was 1.20±1.64), however, the difference was not significant. CONCLUSION: Periodontal endoscopy aiding subgingival debridement could improve periodontal status by reducing the PD and BI significantly in short term.The effect was almost the same with periodontal surgery and endoscopy treatment may decrease the necessity of surgery.Meanwhile, periodontal endoscopy has more comfortable treatment experience than flap surgery and does not need extra treatment time.

[Multivariable analysis of tooth loss in subjects with severe periodontitis over 4-year natural progression].

OBJECTIVE: To evaluate the characteristics of severe periodontitis with various number of tooth loss during 4-year natural progression, and to analyze the factors related to higher rate of tooth loss. METHODS: A total of 217 patients aged 15 to 44 years with severe periodontitis were included, who participated in a 4-year natural progression research. Data obtained from questionnaire survey, clinical examination and radiographic measurement. Tooth loss during 4-year natural progression was evaluated. The baseline periodontal disease related and caries related factors were calculated, including number of teeth with bone loss > 50%, number of missing molars, number of teeth with widened periodontal ligament space (WPDL), number of teeth with periapical lesions and etc. Characteristics of populations with various number of tooth loss and the related factors that affected higher rate of tooth loss were analyzed. RESULTS: In 4 years of natural progression, 103 teeth were lost, and annual tooth loss per person was 0.12±0.38. Nine patients lost 3 or more teeth. Thirty-four patients lost 1 or 2 teeth, and 174 patients were absent of tooth loss. Molars were mostly frequent to lose, and canines presented a minimum loss. The number of teeth with WPDL, with periapical lesions, with intrabony defects, with probing depth (PD)≥7 mm, with PD≥5 mm, with clinical attachment loss≥5 mm, with bone loss > 50% and with bone loss > 65% were positively correlated to number of tooth loss. Results from orderly multivariate Logistic regression showd that the number of teeth with bone loss > 50% OR=1.550), baseline number of molars lost (OR=1.774), number of teeth with WPDL (1 to 2: OR=1.415; ≥3: OR=13.105), number of teeth with periapical lesions (1 to 2: OR=4.393; ≥3: OR=9.526) and number of teeth with caries/residual roots (OR=3.028) were significant risk factors related to higher likelihood of tooth loss and multiple tooth loss. CONCLUSION: In 4 years of natural progression, the number of teeth with bone loss > 50%, baseline number of missing molars, number of teeth with WPDL, baseline number of teeth with periapical lesions and number of teeth with caries/residual roots were significantly related to higher risk of tooth loss and multiple tooth loss among Chinese young and middle-aged patients with severe periodontitis in rural areas.

[Role of growth arrest-specific protein 6 in migration and osteogenic differentiation of human periodontal ligament cells].

OBJECTIVE: To investigate the role of growth arrest-specific protein 6 (Gas6) in the process of the migration and osteogenic differentiation of human periodontal ligament cells (hPDLCs). METHODS: After different concentrations of recombinant human Gas6 (rhGas6) were added to hPDLCs, cell prolife-ration experiment (CCK-8) was taken to observe the effect of rhGas6 on hPDLCs cell proliferation. Scratch test and cell migration test (Transwell) were taken to analyze the migratory ability of hPDLCs in different concentrations of rhGas6 groups. After osteogenic induction, real-time quantitative polymerase chain reaction (real-time PCR) was taken to detect the expression of the Runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP). ALP staining was used to detect the amount of mineralized nodules. RESULTS: After adding different concentrations of rhGas6, there were no statistically significant differences in hPDLCs cell proliferation among the experimental groups and the control group at 24, 48 and 72 hours (P>0.05). After 24 h of scratch, the healing area in the 800 µg/L of the rhGas6 group was greater than that in the control group, but without statistically significant difference (31.06%±13.70% vs. 21.79%±9.51%, P>0.05). In the migration test, after 24 h, the number of hPDLCs cells which penetrated through the membrane in the 800 µg/L rhGas6 group was significantly higher than that in the control group (P < 0.01). After rhGas6 was added and osteogenic induction, Runx2 and ALP gene expressions of hPDLCs in the 800 µg/L group were significantly higher than those in the control group (1.60±0.30 vs. 0.91±0.10, 2.81±0.61 vs. 0.86±0.12, P < 0.01). After Gas6 was knocked down, the ALP expression of hPDLCs was significantly lower than that of the control group (0.39±0.07 vs. 0.92±0.14, P < 0.01). There was no significant change in Runx2 expression (P>0.05). After 7 days of osteogenic induction, the mineralized nodules formed in the Gas6 knockdown group were significantly less than those in control group (0.25±0.04 vs. 1.00±0.11, P < 0.001). After 14 days of induction, the staining degree of the Gas6 knockdown group was lower than that of the control group, but there was no significant difference (0.86±0.04 vs. 1.00±0.16, P>0.05). CONCLUSION: After downregulation of Gas6 gene, mineralized nodule formation was reduced and ALP gene expressions were decreased in the early stage of osteogenic induction (7 days). After addition of rhGas6, Runx2 and ALP gene expressions were increased and the number of cell migration was increased, suggesting that Gas6 might play a promoting role in the migration and osteogenic differentiation of human periodontal ligament cells.

[Gingival thickness assessment of gingival recession teeth].

OBJECTIVE: To evaluate the gingival thickness and gingival biotype of gingival recession teeth of Chinese population. METHODS: A total of 112 non-molar teeth with gingival recession in 34 patients were included. Direct measurement, cone-beam computerized tomography (CBCT) measurement and periodontal probe method were used to evaluate gingival thickness and biotype. Gingival thickness was measured at 2 mm apical to the gingival margin. Direct measurement was performed with a caliper of 0.01 mm resolution and anesthesia needles attached to silicone disk stops. Gingival biotype was assessed by sulcus probing, if the periodontal probe was visible through the gingival tissue, the gingival biotype was thin; If not visible, the gingival biotype was thick. The differences of gingival thickness among different gingival biotype, tooth site and gingival recession type were analyzed respectively. Besides, the results of CBCT measurement was analyzed compared with the direct measurement. RESULTS: The average gingival thickness of non-molar recession teeth was (1.17±0.41) mm. The average gingival thickness of thick and thin biotype group were (1.38±0.4) mm and (0.97±0.30) mm, respectively, with statistically significant difference (P<0.001). The median of gingival thickness was 1.1 mm. Using 1.1 mm as the cut-off value of thick and thin gingival thickness group, the results matched well with the gingival biotype classification results by periodontal probe method (P=1.000). The average gingival thickness of maxillary teeth was significantly thicker than that of the mandibular teeth. They were (1.39±3.44) mm and (1.01±0.31) mm, respectively (P<0.001). The mean gingival thickness of MillerI, II and III degree gingival recession teeth were (1.15±0.34) mm, (0.83±0.17) mm and (1.26±0.56) mm, respectively, without statistically significant difference (P=0.205). The gingival thickness measurement results between CBCT method and direct measurement were without statistically significant difference (P=0.206). CONCLUSION: In the non-molar gingival recession teeth, the cut-off value of gingival thickness to classify thick and thin biotype of Chinese population was 1.1 mm. The average gingival thickness of the maxillary teeth was significantly thicker than that of the mandibular teeth. Besides, CBCT measurement was an accuracy method for evaluating facial gingival thickness.

[Vestibular incision subperiosteal tunnel access with connective tissue graft for the treatment of Miller classI and II gingival recession].

OBJECTIVE: To evaluate the clinical outcomes of vestibular incision subperiosteal tunnel access (VISTA) with connective tissue graft (CTG) in the treatment of Miller classes I and II localized gingival recession. METHODS: Ten patients with 10 Miller classes I and II localized gingival recessions were enrolled in the study. All defects were equal to or above 2 mm in recession depth. All the patients received treatment with VISTA+CTG. Their clinical parameters, including recession depth (Rec), recession width (RW), keratinized tissue width (KT), clinical attachment loss (CAL), probing depth (PD) were recorded and compared before surgery and 6 months later. The mean root coverage (MRC) and complete root coverage (CRC) were calculated at the end of 6 months. A visual analogue scale (VAS) was used to estimate the patients' discomfort during the operation and during the 2 weeks post-operation. Patient-based aesthetic satisfaction 6 months after surgery was evaluated by a VAS. RESULTS: The mean Rec was (2.65±0.82) mm at baseline, and (0.35±0.58) mm after 6 months. The VISTA+CTG treatment resulted in an improvement of (2.30±0.98) mm in recession depth (P<0.001). MRC was 86.67%±21.94% and CRC reached 70% at the end of 6 months. KT increased (0.90±1.22) mm (P<0.05). Aesthetic satisfaction on the patients' level was 8.30 based on VAS (0=unsatisfied, 10=extremely satisfied). The patients' discomfort during the operation and 2 weeks post operation were 2.40 and 4.30 (0=no pain, 10=extreme pain). Furthermore, clinical outcomes showed no statistically significant difference between the gingival biotypes, and between the teeth positioned in maxillary and in mandibular. CONCLUSION: VISTA+CTG could be an effective treatment for Miller classes I and II localized gingival recession. Clinical outcomes indicated decrease in recession depth and width, and increase in width of keratinized tissue. Patients suffered little pain during the operation and 2 weeks post-operation of healing and accessed good aesthetic satisfaction. VISTA+CTG could be an option for the treatment of Miller classes I and II localized gingival recession.

[Role of vitamin K-dependent protein Gas6 in the expression of endothelial cell adhesion molecule-1 and chemokines induced by Porphyromonas gingivalis lipopolysaccharide].

OBJECTIVE: Growth-arrest-specific protein 6 (Gas6) is a vitamin K-dependent protein and involved in cell proliferation, survival, adhesion and migration . Also it has been shown to play an important role in the inflammatory response .The aim of present study was to investigate the role of Gas6 in the process of the expression of adhesion molecules and chemokines of human umbilical vein endothelial cells (HUVECs) induced by Porphyromonas gingivalis lipopolysaccharide(P.g-LPS). METHODS: After up-regulation and down-regulation of the expression of Gas6, the vascular endothelial cells were stimulated with 1 mg/L P.g-LPS for 3 h and 24 h. Real-time quantitative polymerase chain reaction(real-time PCR) was taken to detect the expression of the cell adhesion molecules:intercellular adhesion molecule-1 (ICAM-1) and E-selectin, as well as chemokines:interleukin-8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1). Wound healing assay was taken to observe the migration ability of endothelium cells in different groups. RESULTS: After 3 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in the down-regulation group was not significantly different from that in the control group,while in the up-regulation group the decrease of E-selectin, ICAM-1, IL-8 and MCP-1 was 81%±0%, 47%±3%, 76% ± 3%, 26% ± 6% respectively. After 24 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in down-regulation group was significantly higher than that in control group (2.06±0.07, 1.99±0.11, 3.14±0.15, 1.84±0.03 flod), while these molecules in the down-regulation group was significantly lower than in the control group (29%±1%, 62%±3%, 69%±1%, 41%±2%). Differences were statistically significant (P<0.01). Wounding healing assay showed that down-regulation of Gas6 enhanced migration ability of endothelial cells while up-regulation of Gas6 weakened this ability,which was consistent with the trend of real-time PCR result. CONCLUSION: Down-regulation of the Gas6 gene enhanced the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g- LPS stimulating, while up-regulaiton of the Gas6 gene weakened the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g-LPS stimulating,suggesting that Gas6 may play a role in the process of endothelial cell adhesion.

[Observation of bone morphology in furcation defects of mandibular molars using cone beam computed tomography].

OBJECTIVE: To observe mesial-distal bone morphology in classes II and III furcation involvements (FI) of mandibular molars using cone beam computed tomography (CBCT), to develop a classification system of mesial-distal bone morphology of furcation defects and to observe the intrabony defects on CBCT images. METHODS: Based on the existing CBCT data, the mandibular molars with horizontal bone defects in furcation area were observed. One hundred and seventeen sites of 81 mandibular molars with class II or class III FIclassified on CBCT images were included. The classification system of mesial-distal bone morphology of furcation defects was developed. According to the location of the line drawn from mesial to distal alveolar bone crest (AC-line) of the tooth and bone level under furcation fornix, the bone morphology was classified into three types, including concave type, flat type and protruding type. The concave type was divided into two subtypes according to the location of AC-line and furcation fornix (Fx), which were subtype 1(AC-line coronal or equal to Fx)and subtype 2 (AC-line apical to Fx).The frequency of each type was calculated and analyzed. The intrabony defects was observed on sagittal CBCT images. RESULTS: In the 117 sites with FI, the flat type appeared with the highest rate (64.10%) and the protruding type appeared with the lowest rate (6.84%). The rates of subtype 1 and subtype 2 of concave type were 13.68% and 15.38%, respectively. The rate of subtype1 which was supposed to be beneficial for bone regeneration was 8.96% in class II FI and 20.00% in class III FI. Thirtyone intrabony defects were found among the 117 FI, 29 of which appeared in proximal aspect of the tooth and the left 2 appeared in furcation area. The highest frequency of the intrabony defects was found in subtype 1 of concave type. CONCLUSION: The classification of mesial-distal bone morphology on CBCT images may be helpful for clinicians to make accurate treatment plan before surgery and could be used in future studies to understand the influence of bone morphology on regenerative therapy for furcation defects.

[Combination of periodontal, orthodontic and endodontic therapy in upper anterior teeth with hopeless prognosis and long-time follow-up: a case report].

It is complicated to decide the treatment plan of hopeless anterior teeth in esthetic zone due to severe periodontitis, periodontal-endodontic combined lesion or teeth trauma. The optional treatment plan for this kind of teeth includes retention after periodontal treatment, extraction and implant treatment, extraction and prosthodontic treatment and so on. To make an appropriate treatment plan, patients' periodontal conditions, periodontal biotype, local anatomy, esthetic demand, economic condition and social psychological status should be comprehensively considered. A combine of periodontal, endodontic and orthodontic therapy may achieve a good treatment effect in hopeless anterior teeth with severe periodontal destruction, tooth extrusion and occlusal trauma. In this case, a 20-year-old female who presented with symptoms of bleeding on brushing and upper incisors loosening for 1 month came to the Department of Periodontology, Peking University School and Hospital of Stomatology. The clinical examinations revealed that the patient's right upper incisor had signs of mobility (III°), intrusion of 1-2 mm, and probing depth (PD) of 9-10 mm. The periapical radiograph showed that the alveolar bone of right upper incisor absorbed horizontally to the apex. And the patients showed Angle II° malocclusion with II° overbite in anterior teeth and maxillary protrusion. A diagnosis of aggressive periodontitis and Angle II° malocclusion was made. The treatment of this patient lasts for 5 years which include periodontal initial therapy, orthodontic therapy, guided tissue regeneration (GTR) of right upper incisor and supportive periodontal therapy and the clinical result is fine. A hopeless upper incisor was successfully retained and the longtime clinical condition was stable. The strategy of retention of hopeless upper anterior teeth, the relationship of periodontal treatment and orthodontic treatment, and the indications of periodontal and orthodontic combined therapy were also discussed on the basis of this case. Generally, the positive factors in retention of hopeless teeth includes young age, absence of systemic conditions, strong motivation for maintaining the tooth, single root anatomy, integrated dentition, good response to cause-related therapy, intrabony alveolar bone defect, thick periodontal biotype, and regular supportive periodontal therapy. And in the progress of orthodontic therapy, regular supportive periodontal therapy and good plaque control is extremely important.

Passively Q-switched Nd:YAG/Cr(4+):YAG bonded crystal microchip laser operating at 1112 nm and its application for second-harmonic generation.

A passively Q-switched Nd:YAG/Cr4+:YAG microchip laser operating at 1112 nm is demonstrated. Under a pump power of 5.5 W, a maximum average output power of 623 mW was obtained with T=6% output coupler, corresponding to an optical-to-optical conversion efficiency of 11.3% and a slope efficiency of 19.5%. The minimum pulse width was 2.8 ns, the pulse energy and peak power were 39.3 µJ and 14 kW, respectively. Additionally, based on the 1112 nm laser, a 230 mW 556 nm green-yellow laser was achieved within an LBO crystal.

[Exploration and practice of Peking University Model to improve the clinical teaching effect of clinical postgraduates majoring in periodontology].

The number of patients with periodontal disease in China is large, and the ratio of doctors to patients is seriously imbalanced, especially in the insufficient number of periodontal specialists and periodontal teachers. Strengthening the cultivation of professional postgraduates in periodontology can effectively solve this problem. This paper summarizes the experiences of Peking University School and Hospital of Stomatology in the teaching of periodontal postgraduate students for more than 30 years, in cluding teaching objectives formulation, teaching resources allocation and enhancement of the quality control system of clinical teaching, for ensuring that the periodontal professional postgraduates could reach the expected level after training. This formed the current "Peking University Model". There are both opportunities and challenges in clinical teaching of periodontal postgraduates in domestic stomatology community. The authors hope that the continuous exploration and improvement of this teaching system will promote the vigorous development of clinical teaching for the postgraduates majoring in periodontology in China.

[A survey on human resources of dentists who deal with periodontal disease in Beijing].

Objective: To investigate the status quo of human resources of dentists who deal with periodontal disease in Beijing area through an online survey, which may hopefully provide a preliminary basis for the decision-making of administrative departments and the formulation of periodontal professional development plan. Methods: The dentists who deal with periodontal disease at least half a day per week in Beijing area were investigated. A questionnaire was designed by the chairman of the Periodontology Committee of Beijing Stomatological Association. The questionnaire was sent to and finished by the dentists via "WenJuanXing" online survey software. The contents of the survey included general condition, the property of practice unit, title and position of the dentist, membership of professional society, time and content of periodontal treatment, adoption of new technology and new method of periodontal therapy during the past one year, status of periodontal treatment in the local population and reasons, understanding and influencing factors of periodontal professional development. Results: A total of 1 255 dentists completed the survey, who came from all 16 districts in Beijing, mainly Haidian, Chaoyang, Dongcheng and Xicheng Districts [The total percentage of these four main districts was 70.3% (882/1 255)]. The mean age of the dentists was (36.1±8.3) years. Among the dentists, 71.1% (892/1 255) were females, 88.1% (1 106/1 255) got a Bachelor's degree or above. It was estimated that 35.4% (444/1 255) of the dentists had received standardized periodontal training ever. The percentage of dentists carrying out new technology in the past one year was as high as 68.1% (855/1 255). There were only 163 periodontal specialists (13.0%) out of the dentists in the survey. Only 15.9% (200/1 255) of the dentists routinely performed periodontal surgery. The majority of the dentists [82.8% (1 039/1 255)] were from the state-owned hospitals. Fifty-four point seven percemt (686/1 255) of the dentists thought that lack of knowledge was the main reason why the general public failed to receive periodontal treatment. As for the biggest bottleneck affecting periodontal professional development, fifty-one point zero percent (640/1 255) of the dentists attributed it to the public neglect. Conclusions: The periodontal practitioners in Beijing are young, highly educated, unevenly distributed in 16 districts and mostly females. State-owned oral health institutions are an important force in periodontal diagnosis and treatment services in Beijing. The number of periodontal specialists need to be improved. Promotion of standardized periodontal surgery and the popularization of healthcare knowledge on periodontal disease should also be the focus in the future.

Trypsin-like protease-active extracellular protein extracts from Porphyromonas gingivalis ATCC 33277 induce apoptosis in bovine aortic endothelial cells.

BACKGROUND AND OBJECTIVE: Certain virulence factors participating in periodontitis may relate to cardiovascular diseases. This study was to evaluate the pro-apoptotic effect of protein extracts from Porphyromonas gingivalis on bovine aortic endothelial cells (BAECs). MATERIAL AND METHODS: The BAECs were exposed to trypsin-like protease-active protein extracts from P. gingivalis, and apoptosis was examined by Hoechst 33342 staining, DNA fragmentation assay and cleaved caspase-3 detection. When BAECs were exposed to protein extracts pretreated with trypsin-like protease inhibitor (TLCK), the apoptosis rate was evaluated by Annexin V-propidium iodide staining. To further study the potential mechanism of the pro-apoptotic effect, immunoblotting was used to detect expression of alpha-tubulin, integrin beta1 and activated ERK1/2 in BAECs treated with protein extracts or cultured in suspension. RESULTS: After exposure to the protein extracts, BAECs exhibited loss of cell adhesion and apoptotic cell death. The pro-apoptotic effect could be delayed by TLCK pretreatment. In addition, BAECs treated with protein extracts showed decreased levels of alpha-tubulin, integrin beta1 and activated ERK1/2. When BAECs were cultured in suspension, ERK1/2 activation was also inhibited, but the percentage decrease in ERK1/2 activation was less than that induced by protein extracts. Moreover, no significantly altered expression of alpha-tubulin was detected in suspended cells. CONCLUSION: Trypsin-like protease-active protein extracts from P. gingivalis could induce apoptosis of BAECs. The destruction of alpha-tubulin and integrin beta1 and decrease of ERK1/2 activation might contribute to the pro-apoptotic effect of the protein extracts.

[Comparison of two training protocols in periodontal surgery teaching for undergraduate students].

Objective: To compare the efficacies of two training protocols, i.e. the multimedia instruction and the conventional method, in periodontal surgery teaching for undergraduate students. Methods: One hundred and twenty-three dental undergraduates in their pre-clinical training course were recruited and divided into two groups according to the learning grade matching principle: the experimental group (multimedia instruction, 60 students) and the control group (conventional method, 63 students). The teaching aim was to train the students gingivectomy and periodontal flap surgery by using the pig jaws. The conventional teaching method of teacher-demonstrating and student-practicing was used in the control group, and the practice time of the students' for each surgery was 45 minutes. A standardized teaching video combined with the teachers' explanations of the key steps was used in the experimental group. The students' practice time for each surgery was 60 minutes. The efficacy of teaching protocol was evaluated by the teachers according to the scoring criteria set by the teaching group. Results: In gingivectomy training, accuracy of fixed points, angle of postoperative gingival margin and morphology of gingiva of the experimental group were better than those of the control group. The experimental group also had more complete and continuous excised gingivae and more thorough adjacent gingival removal. The total scores of the experimental group were significantly higher than those of the control group (92.8±2.6 vs. 89.9±3.7, P<0.05). In periodontal flap surgery training, the experimental group operated the blade around the shape of the tooth better in internal bevel incision than the control group. Additionally, the incision position of internal bevel incision, periosteal integrity after flapping and flap depth of the experimental group were better than those of the control group. Besides, the experimental group had smoother flap edge and more thorough debridement. The total scores of the experimental group were significantly higher than those of the control group (92.2±4.1 vs. 89.2±4.4, P<0.05). Conclusions: The teaching efficacy of multimedia instruction was better than that of the conventional method. Its value needs to be further tested in future teaching practice.

[State of the art diagnostic criteria of severe periodontitis].

Periodontitis could be categorized as mild, moderate, and severe according to the severity of the disease. This categorizing system could also be used together with other classification systems. The present article introduced the status about the case definition of severe periodontitis, including the standard of case definitions for surveillance of periodontitis reported by the Centers for Disease Control and Prevention (CDC) in partnership with the American Academy of Periodontology (AAP) and the consensus report on the definition of periodontitis case for use in risk factor research by Europe workshop. A consensus on the state of the art definition of severe periodontitis for use in clinical work was gained base on the expertise of Chinese Society of Periodontology, Chinese Association of Stomatology. The background of this consensus and the significance of the criteria for the case definition were discussed.

[A clinical evaluation of periodontal treatment effect using periodontal endoscope for patients with periodontitis: a split-mouth controlled study].

Objective: To compare the clinical effects of periodontal treatment using periodontal endoscope with that of conventional treatment method for patients with periodontitis. Methods: Eleven periodontal patients with moderate to advanced periodontal destruction were recruited and treated with scaling and root planing in a split-mouth design randomly with (test group) or without (control group) periodontal endoscope. Changes of such clinical parameters as plaque index (PLI), bleeding index (BI), probing depth (PD) and attachment loss (AL) before and after treatments as well as the difference between test and control groups were examined and compared. Results: Both groups showed significant reductions in PD, BI and AL values at 6 weeks and 3 months after treatment (P <0.001). Only in the test group, for sites with PD≥6 mm at baseline, PD value ([4.0±1.2] mm) and AL value ([3.8±0.9] mm) at the end of 3 months were significantly lower than that at the end of 6 weeks (PD[4.4±1.3] mm, P<0.001; AL[4.1±1.1] mm, P< 0.05). There were no significant differences between two groups at the baseline, at the end of 6 weeks and 3 months, respectively. However, for the sites with PD≥6 mm in anterior teeth, PD value in test group at the end of 3 months was significantly lower than that in control group ([3.2±0.9] mm vs [3.7±0.9] mm, P <0.05), while AL value tend to be lower ([2.9 ± 1.2] mm vs [3.6 ± 1.3] mm, P=0.061). Conclusions: Periodontal treatment using endoscope is obviously effective, especially for the medium and long term prognosis of deep pockets and single rooted teeth.

E-selectin expression induced by Porphyromonas gingivalis in human endothelial cells via nucleotide-binding oligomerization domain-like receptors and Toll-like receptors.

Porphyromonas gingivalis, an important periodontal pathogen, has been proved to actively invade cells, induce endothelial cell activation, and promote development of atherosclerosis. Innate immune surveillance, which includes the activity of nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) and Toll-like receptors (TLRs), are essential for the control of microbial infections; however, the roles of receptor families in P. gingivalis infections remain unclear. Here, we examined the roles of NLRs and TLRs in endothelial cell activation caused by P. gingivalis. Live P. gingivalis and whole cell sonicates were used to stimulate endothelial cells, and both showed upregulation of E-selectin as well as NOD1, NOD2, and TLR2. In addition, silencing of these genes in endothelial cells infected with P. gingivalis led to a reduction in E-selectin expression. Porphyromonas gingivalis also induced nuclear factor-κB (NF-κB) and P38 mitogen-activated protein kinase (MAPK) activity in endothelial cells, whereas small interfering RNA targeting NOD1 significantly reduced these signals. Moreover, inhibition of either NOD2 or TLR2 inhibited NF-κB significantly, but had only a weak inhibitory effect on P38 MAPK signaling. Direct inhibition of NF-κB and P38 MAPK significantly attenuated E-selectin expression induced by P. gingivalis in endothelial cells. Taken together, these findings suggest that NOD1, NOD2, and TLR2 play important, non-redundant roles in endothelial cell activation following P. gingivalis infection.

[Relationship of serum and gingival crevicular fluid antibody levels with the amount of subgingival homologous bacterium in patients with periodontal disease].

39 patients were selected in this study, including 12 patients with rapidly progressive periodontitis (RPP), 17 with adult periodontitis (AP) and 10 with marginal gingivitis (MG). The levels of antibody to Porphyromonas gingivalis (Pg) in serum (Sr) and in gingival crevicular fluid (GCF) from their 156 teeth were measured by ELISA. The Pg in subgingival plaque was detected by indirect immunofluorescence technique. Data showed different GCF/Sr ratio of anti--Pg antibody level between periodontitis patients (lower than 1) and MG patients (greater than 1). The amount of subgingival Pg was negatively correlated with clinical periodontal parameters, i.e, probing depth, attachment loss, plaque index and bleeding index. It was suggested that low GCF/Sr ratio of antibody level plus high counts of homologous bacterium might be used as an indicator of periodontal disease activity.

[Relationship between gingival crevicular fluid and serum specific antibody titers in periodontitis and changes after the treatment].

Gingival crevicular fluid (GCF) samples were collected from 80 teeth in 20 periodontitis patients (13 RPP, 7 AP) before and 1 month, 7 months after treatment. Serum samples were taken at the same time. 12 healthy subjects (48 teeth) were chosen as the control group (H). The levels of IgG antibody to Bacteroides gingivalis was measured by ELISA. The relationship between serum and GCF specific antibodies was assessed. Before treatment, the mean ratio of antibody in GCF and serum (the GCF/Sr ratio) in both RPP and AP group was lower than 1, and significantly lower than that in H group. After treatment, the serum antibody titers greatly reduced while GCF antibody increased at 1 month after treatment and decreased at 7 months after treatment. The GCF/Sr ratio raised to greater than 1 in both RPP and AP. The elevation of GCF antibody may be associated with the lower antibody consumption caused by decreasing amount of B. gingivalis in pocket, and/or associated with the local antibody synthesis. It was suggested that the GCF/Sr ratio of antibody level might be used as a significant indicator in evaluation of treatment effectiveness.

[The value of using serum specific antibody in differential diagnosis of periodontitis].

In the present study, serum anti-Bacteroides gingivalis (Bg) and anti-Actinobacillus actinomycetemcomitans (Aa) antibody titers in RPP, AP patients and healthy subjects were determined by ELISA. Discriminant analysis for differential diagnosis of RPP, AP and healthy subjects was performed using clinical measurements (PD, AL, PII, BI) and serum antibody levels as combined parameters. The results showed significantly different serum antibody levels among the three examined groups. The results also suggested that the combined use of clinical parameters and serum specific antibody titers may be a valuable measure in differential diagnosis of periodontal diseases.