[Constructing the Bayesian network models to explore the factors related to glomerular and tubular injury].

Objective: To construct Bayesian network (BN) models to explore the factors related to glomerular injury (GI) and tubular injury (TI). Methods: A cross-sectional study was carried out. From April to November 2019, Shanxi Provincial People's Hospital performed an opportunistic screening for chronic kidney disease in 10 counties of Shanxi Province. The general data and laboratory results of blood and urine samples were collected. Chi-square test and logistic regression were used to explore the related factors of GI and TI, which were included in the construction of BN models with max-min hill-climbing (MMHC) algorithm. Results: A total of 12 269 participants were included, there were 5 198 males and 7 071 females, with a median age of 58 (40-91) years. The prevalence of GI and TI was 12.7% (1 561/12 269) and 11.6% (1 425/12 269), respectively. The BN model consisted of 8 nodes and 10 edges for GI, and 11 nodes and 17 edges for TI, respectively. BN models showed that age and glycated hemoglobin were direct related factors for GI, while gender and fasting blood glucose were indirect related factors for GI. Age, gender, fasting blood glucose and glycosylated hemoglobin were direct related factors for TI. Additionally, the area under the receiver operating characteristic curve (AUC) was 0.761 (95%CI: 0.746-0.777) and 0.753 (95%CI: 0.736-0.769) for GI and TI BN models, respectively. Conclusions: BN models allow for identifying the complex network relationships among the factors related to GI and TI. Meanwhile, Bayesian risk reasoning can provide reference value for the clinical prevention of GI and TI.

[Occupational protection effect of two protective devices for manual cleaning and oiling of dental handpieces on operators].

Objective: To explore the occupational protective effect of different protective devices on the operators during manual cleaning and oiling of dental handpieces, and to provide a basis for the selection of appropriate protective methods. Methods: From November 2020 to December 2021, 20 high-speed dental handpieces of the same brand were selected and randomly divided into disposable protective bag group and small aerosol safety cabinet group by drawing lots, with 10 in each group. After recording the model, they were distributed to the clinical fixed consulting room for use, and were collected by specially-assigned personnel every day for manual cleaning under the protection of the two devices. By measuring the number of airborne colonies, the concentrations of particulate matter and the satisfaction of operators, the occupational protection effect of the two protective devices on operators was evaluated. Results: Under the protection of the two devices, the average number of airborne colonies after operation was less than 1 CFU/ml. When no protective device was used, the number concentration of particulate matter produced during operation was (21595.70±8164.26) pieces/cm(3). The number concentrations of particles produced by disposable protective bag group [ (6800.24±515.05) pieces/cm(3)] and small aerosol safety cabinet group [ (5797.15±790.50) pieces/cm(3)] were significantly lower than those without any protective device (P<0.001). The number concentration of particle matter of small aerosol safety cabinet group was significantly lower than that of disposable protective bag group (P<0.001). In the satisfaction evaluation of operators, small aerosol safety cabinet group [ (3.53±0.82) points] was significantly better than disposable protective bag group [ (2.23±1.10) points] (P<0.001) . Conclusion: The use of small aerosol safety cabinet during manual cleaning and oiling of dental handpieces has good protective effect, superior safety performance and strong clinical applicability, and has advantages in occupational protection of clinical operators.

[Clinical classification and treatment decision of implant fracture].

OBJECTIVE: To propose a set of two-dimensional clinical classification of fractured implants based on the follow-up of fracturing pattern of implant body and peri-implant bone defect morphology of 32 fractrued implants, and summarize the treatment decisions of fractured implants according to this new set of classification, so as to provide guidance for clinical practice. METHODS: During 25 years of clinical practice, clinical records of 27 patients of 32 fractured implants in 5 481 patients with 10 642 implants were made. The fracturing pattern of implant body, implant design, peri-implant bone defect morphology and treatment options were analyzed. A set of two-dimensional clinical classification based on the morphology and bone absorption of implant fracture was proposed. The treatment decision-making scheme based on the new classification of implant fracture was discussed. RESULTS: In the new classification system, vertical fracture of implant neck (Type 1 of implant fracture morphology, F1) and horizontal fracture of implant neck (Type 2 of implant fracture morphology, F2) were common, accounting for 50% and 40.6% respectively, while deep horizontal fracture of implant body (Type 3 of implant fracture morphology, F3) (9.4%) were rare, while the three types of bone defects (D1, no bone defect or narrow infrabony defects; D2, wide 4-wall bone defects or cup-like defects, D3, wide 3-wall or 2-wall defects) around implants were evenly distributed. In the two-dimensional classification system of implant fracture, F1D1 (31.3%) and F2D2 (25%) were the most frequent. There was a significant positive correlation between F1 and D1 (r=0.592, P < 0.001), a significant positive correlation between F2 and D2 (r=0.352, P=0.048), and a significant negative correlation between F1 and D2 (r=-0.465, P=0.007). The most common treatment for implant fracture was implant removal + guided bone regeneration(GBR) + delayed implant (65.6%), followed by implant removal + simultaneous implant (18.8%). F1D1 type was significantly related to the treatment strategy of implant removal + simultaneous implantation (r=0.367, P=0.039). On this basis, the decision tree of implant fracture treatment was summarized. CONCLUSION: The new two-dimensional classification of implant fracture is suitable for clinical application, and can provide guidance and reference for clinical treatment of implant fracture.

[Application evaluation of prefabricated rigid connecting bar in implants immediate impression preparation of edentulous jaw].

OBJECTIVE: To compare the operation complexity and accuracy of traditional splint impression technique and impression technique with prefabricated rigid connecting bar system for full-arch implants-supported fixed protheses in vitro. METHODS: Standard mandibular edentulous model with six implant analogs was prepared. The implants were placed at the bone level and multiunit abutments screwed into the implants. Two impression techniques were performed: the traditional splint impression technique was used in the control group, and the rigid connecting bar system was used in the test group. In the control group, impression copings were screwed into the multiunit abutments and connected with autopolymerizing acrylic resin. Open tray impression was fabricated with custom tray and polyether. In the test group, cylinders were screwed into the multiunit abutments. Prefabricated rigid bars with suitable length were selected and connected to the cylinders with small amount of autopolymerizing acrylic resin, and open tray impression was obtained. Impression procedures were repeated 6 times in each group. The working time of the two impression methods were recorded and compared. Analogs were screws into the impressions and gypsum casts were poured. The gypsum casts and the standard model were transferred to stereolithography (STL) files with model scanner. Comparative analysis of the STL files of the gypsum casts and the standard model was carried out and the root mean square (RMS) error value of the gypsum casts of the control and test groups compared with the standard model was recorded. The trueness of the two impression techniques was compared. RESULTS: The work time in the test group was significantly lower than that in the control group and the difference was statistically significant [(984.5±63.3) s vs. (1 478.3±156.2) s, P < 0.05]. Compared with the standard model, the RMS error value of the implant abutments in the test group was (16.9±5.5) µm. The RMS value in the control group was (20.2±8.0) µm. The difference between the two groups was not significant (P>0.05). CONCLUSION: The prefabricated rigid connecting bar can save the chair-side work time in implants immediate loading of edentulous jaw and simplify the impression process. The impression accuracy is not significantly different from the traditional impression technology. The impression technique with prefabricated rigid connecting bar system is worthy of clinical application.

[A real-world study of the efficacy and safety of sofosbuvir and velpatasvir in the treatment of HCV-infected patients in a county in northern China].

Objective: To evaluate the real-world efficacy and safety of sofosbuvir and velpatasvir (SOF/VEL) tablets in the treatment of Chinese patients with chronic HCV infection. Methods: An open-label, single-center, prospective clinical study was conducted in a county in northern China. A total of 299 cases were enrolled. Of these, 161 cases with chronic hepatitis C and 73 cases with compensated cirrhosis received SOF/VEL for 12 weeks. 65 cases with decompensated cirrhosis received SOF/VEL combined with ribavirin for 12 weeks (22 cases) or SOF/VEL for 24 weeks (43 cases). Virological indicators, liver and renal function indexes, and liver stiffness measurement were detected at baseline, the fourth week of treatment, the end of treatment, and the 12-weeks of follow-up. Adverse reactions and laboratory abnormalities were observed during the course of treatment . The primary endpoint was undetectable rate of HCV RNA (SVR12) at 12 weeks of follow-up with the use of modified intention-to-treat (mITT) approach. Measurement data between two groups were compared using t-test. One Way ANOVA was used for comparison between multiple groups. Enumeration data were analyzed by chi-square test or Fisher's exact test. Results: 291 cases had completed treatment. HCV RNA was undetectable after 12 weeks of follow-up, and the SVR12 rate was 97.3% (95% confidence interval: 95.4%-99.3%). Among them, 97.4% of genotype 1b, 96.4% of genotype 2a, and 100% of those with undetected genotype achieved SVR12. The SVR12 rates in patients with chronic hepatitis C, compensated and decompensated liver cirrhosis were 98.1%, 98.6% and 93.8%, respectively. An improvement in alanine aminotransferase, aspartate aminotransferase and other liver biochemical indicators accompanied with virological clearance and reduced liver stiffness measurement was observed in patients with compensated cirrhosis, with statistically significant difference. There was no significant abnormality in renal function before and after treatment. The most common adverse reactions were fatigue, headache, epigastric discomfort and mild diarrhea. The overall adverse reactions were mild. One patient died of decompensated liver cirrhosis combined with massive upper gastrointestinal bleeding, which was unrelated to antiviral treatment. Four patients discontinued treatment prematurely due to adverse events. Relapse was occurred in four cases, and drug-resistance related mutations were detected in three cases. Conclusion: Sofosbuvir and velpatasvir tablets in Chinese HCV-infected patients with different genotypes, different clinical stages or previously treated with pegylated interferon combined with ribavirin resulted in higher SVR12, indicating that the treatment safety profile is good.

[Effect of Porphyromonas gingivalis infection on atherosclerosis in apolipoprotein-E knockout mice].

OBJECTIVE: Studies have indicated that periodontal pathogen Porphyromonas gingivalis (P. gingivalis) infection may contributed to accelerate the development of atherosclerosis. The aim of this study was to investigate the effect of inflammation, oxidative stress and the mechanism on atherosclerosis in apolipoprotein-E knockout (ApoE-/-) mice with P. gingivalis infection. METHODS: Eight-week-old male ApoE-/- mice (C57BL/6) were maintained under specific pathogen-free conditions and fed regular chow and sterile water after 1 weeks of housing. The animals were randomly divided into two groups: (a) ApoE-/- + PBS (n=8); (b) ApoE-/- + P.gingivalis strain FDC381 (n=8). Both of the groups received intravenous injections 3 times per week for 4 weeks since 8 weeks of age. The sham control group received injections with phosphate buffered saline only, while the P. gingivalis-challenged group with P.gingivalis strain FDC381at the same time. After 4 weeks, oxidative stress mediators and inflammation cytokines were analyzed by oil red O in heart, Enzyme linked immunosorbent assay (ELISA) in serum, quantitative real-time PCR and Western blot in aorta. RESULTS: In our study, we found accelerated development of atherosclerosis and plaque formation in aorta with oil red O staining, increased oxidative stress markers [8-hydroxy-2-deoxyguanosine (8-OHdG), NADPH oxidase (NOX)-2 and NOX-4], as well as increased inflammation cytokines [interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α)] in the serum and aorta of the P. gingivalis-infected ApoE-/- mice. Compared with the control group, there was a significant increase protein level of nuclear factor-kappa B (NF-κB) in aorta after P. gingivalis infection. CONCLUSIONS: Our results suggest that chronic intravenous infection of P. gingivalis in ApoE-/- mice could accelerate the development of atherosclerosis by disturbing the lipid profile and inducing oxidative stress and inflammation. The NF-κB signaling pathway might play a potential role in the P. gingivalis-accelerated atherogenesis.

Genetic diversity of HLA-DRB1 alleles in the Tujia population of Wufeng, Hubei Province, China.

We established a genetic database by investigating human leukocyte antigen (HLA)-DRB1 allelic frequencies in a disease-association study in the Tujia population in Wufang, Hubei, China. The allele frequencies of the HLA-DRB1 locus in 262 healthy, unrelated Tujia individuals living in the Wufeng region of the Hubei Province were analyzed using the Luminex HLA sequence-specific oligonucleotide method with a WAKFlow HLA typing kit. A total of 13 alleles were detected at the HLA-DRB1 locus. HLA-DRB1*09 was the most common allele (22.52%), followed by DRB1*08 and DRB1*15 (11.07%), and DRB1*12 and DRB1*04 (10.69%). These data were compared with the results obtained for 10 other ethnic groups living in other regions as well as to Han groups using neighbor-joining dendrograms and principal component analysis. The results showed that the Tujia population has a close genetic relationship with the Middle Han population at the HLA-DRB1 locus. This information will be useful for HLA-DRB1-linked disease-association studies.

[Clinical effect evaluation of immediate implant and immediate restoration with socket-shield technique in aesthetic area: a retrospective study with up to 5-year follow-up].

Objective: To evaluate the clinical effect of socket-shield technique for 5 years after immediate implantation and immediate restoration in aesthetic area. Methods: The retrospective study was conducted between July, 2013 and July, 2020. A total of 29 patients, with 34 implants, who received immediate implantation and immediate restoration with socket-shield technique in the esthetic zone in Department of Fourth Clinical Division, Peking University School and Hospital of Stomatology were included in this study. The implants survival rate, complications and the pink esthetic score (PES) were evaluated (60.2±26.7) months (13-101 months) after operation. The digital models before treatment and at the final follow-up were obtained, to measure the changes of soft tissue. The labial alveolar bone recession was measured by cone-beam CT. Results: All 34 implants survived during follow-up. The PES was (12.80±1.05), there was no significant difference in PES scores between dental positions (F=1.77, P=0.150). The gingival margin recession was (0.12±0.09) mm, and labial contour change at 2 mm apical to the gingival zenith was (0.45±0.17) mm. The labial alveolar bone recession was (0.14±0.46) mm. Conclusions: Immediate implant with socket-shield technique could maintain the gingival margin and labial alveolar bone, and preserve the soft tissue contour well to achieve good esthetic outcome.

Radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning: one-year results of a randomized controlled trial.

The objective of this study was to perform a comparative evaluation of the radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning (BLSFE and LSFE, respectively) when applied concomitantly with implant placement. A randomized controlled clinical trial was conducted between February 1, 2016 and May 1, 2017 including 26 individuals with at least one missing tooth. Participants were randomized 1:1 to undergo BLSFE (10 participants, 16 implants) or LSFE (13 participants, 19 implants). Bovine-derived xenograft was used in both groups and the implants were inserted concomitantly. In the BLSFE group, the antrostomy was covered with a repositioned bone window and then with a concentrated growth factors (CGF) membrane. In the LSFE group, the antrostomy was covered with a CGF membrane. Panoramic radiographs were taken before surgery (T0), immediately postoperative (T1), and at 12 months postoperative (6 months after loading) (T2). Marginal bone loss (MBL), apical bone gain, augmented alveolar bone height, and intra-sinus bone augmentation were evaluated on panoramic radiographs at T2. A linear regression analysis with generalized estimating equation models was performed. The implant survival rate was 100% at 1 year after implant surgery. The residual alveolar bone height at T0 was comparable in the BLSFE and LSFE groups (3.58 ± 1.49 mm vs 4.12 ± 1.61, P = 0.32), as was the alveolar bone height at T1 (13.61 ± 1.82 mm vs 12.38 ± 1.82 mm, P = 0.06). At T2, significantly higher alveolar bone height, intra-sinus bone augmentation, and apical bone gain, and lower distal MBL were observed in the BLSFE group when compared to the LSFE group, with adjusting for covariates (ß = 2.44, 95% CI 1.42-3.46, P < 0.0001; ß = 2.38, 95% CI 1.35-3.41, P < 0.0001; ß = 2.33, 95% CI 1.23-3.42, P < 0.0001; and ß = -0.43, 95% CI -0.83 to -0.02, P = 0.038, respectively). No significant difference was observed for mesial MBL or apical bone resorption at T2. Lateral sinus floor elevation with bone window repositioning may result in higher bone augmentation after 1 year than the traditional approach. Further research is needed to elucidate the effect of lateral sinus floor elevation with bone window repositioning.

[Clinical effect of semilunar-tunnel technique in guided tissue regeneration].

Objective: To evaluate the clinical effectiveness, safety, short-term and long-term clinical and radiographic outcomes of a novel surgical approach, the semilunar-tunnel flap technique (SLTT), applied to guided tissue regeneration and to provide a theoretical basis for the exploration of a more minimally invasive, reliable and stable technique for periodontal tissue regeneration. Methods: Totally 20 patients, who received initial periodontal treatment in the Fourth Clinical Division of Peking University School and Hospital of Stomatology from January 2019 to June 2020, with at least 1 affected tooth in anterior region in the mouth and with intrabony defects were selected and randomly divided into two groups with 10 cases in each group. The test group used the SLTT technique and the control group used the modified papilla preserved technique (MPPT) for guided tissue regeneration. The changes in clinical indices such as clinical attachment level (CAL), probing depth (PD), bleeding index (BI), papilla height loss (PHL, distance from interproximal contact area to the zenith of the papilla), defect depth (distance from bone crest to bottom of the defect) before and 6 months after surgery were evaluated. The early wound healing index (EHI) at 2 weeks after surgery in each of the groups were observed. Results: There were significant reductions in PD [test group: (6.50±0.85) mm before and (2.10±0.74) mm after surgery, control group: (6.60±0.97) mm before and (2.40±0.70) mm after surgery], CAL [test group: (8.70±0.95) mm and (4.00±1.15) mm, control group: (8.40±1.17) mm and (4.50±1.18) mm], BI [test group: 3.00 (2.75, 3.00) and 1.00 (1.00, 2.00), control group: 3.00 (2.00, 3.00) and 1.00 (0.75, 1.25)] and defect depth [test group: (4.71±0.95) mm and (-0.20±0.85) mm, control group: (4.38±0.97) mm and (0.99±0.80) mm] between two groups after surgical treatments in 6 months (P<0.05). The changes in PHL [test group: (2.20±1.03) mm and (2.00±0.94) mm; control group: (1.80±1.23) mm and (2.10±0.99) mm] were not significant. The EHI at 2 weeks postoperation was significantly lower in the test group (1.30±0.48) than in the control group (2.10±0.99) (P=0.042) and the improvement in defect depth change was significantly higher in the test group [(4.91±1.18) mm] than in the control group [(3.39±0.95) mm] (P<0.05). The radiographic bone fill rate in test group (1.05±0.17) was significantly higher than that in the control group (0.78±0.14) (P=0.001). There were no significant differences in the PD, CAL, BI, and PHL change between the test and control groups. Conclusions: The SLTT technique applied to guided tissue regeneration was safe and effective. The technique allowed overgrafting in the bone defect area, obtained more effective hard tissue regeneration and achieved possibly better postoperative aesthetic results.

[Feasibility analysis of visual analogue scale in esthetic evaluation of anterior implant-supported single crown in maxilla].

Objective: To test the reproducibility of the visual analogue scale (VAS) used in the evaluation of the esthetic effect of anterior dental implants, and to explore the factors that affect the correlation between VAS and pink esthetic score/white esthetic score (PES/WES). Methods: From January 2018 to August 2019, a total of 108 doctors and patients were recruited in the Department of Prosthodontics, Implantology and Fourth Clinical Division of Peking University School and Hospital of Stomatology. Among them, there were 35 dental implant specialists who were familiar with PES/WES [implant specialist group, 25 males, 10 females, (37.3±4.5) years old], 34 dentists who were not familiar with PES/WES [dentist group, specialized in Prosthodontics, Periodontology, Orthodontics, and Oral Maxillofacial Surgery, 24 males, 10 females, (36.1±4.2) years old], 39 patients [patient group, 28 males, 11 females, (45.4±8.3) years old]. Twenty oral pictures of patients [12 males, 8 females, (43.7±6.4) years old] treated in the Department of Prosthodontics, Peking University School and Hospital of Stomatology from December 2016 to December 2017 were taken for single implant restoration for esthetic evaluation with VAS. Score 0 for evaluation of not beautiful and score 10 for very beautiful. Re-evaluation of the same 20 pictures with VAS after 1 month, and perform repeatability evaluation of VAS using chi-square test were conducted. At the same time, 13 implant specialists were randomly selected, to score the same photos with PES/WES. The PES scoring elements were the fullness of the mesial gingival papilla, the fullness of the distal gingival papilla, the curvature of the gingival margin, the protrusion of the root surface, the color and the texture of the soft tissue. The scoring elements of WES were crown shape, crown contour, crown color, surface texture, transparency and individual characteristics in order. Pearson correlation analysis was used to evaluate the correlation between the score of VAS and PES/WES. And the influence of the group on the correlation between PES/WES and VAS was analyzed. Results: The PES score was 7.5±1.8, and the WES score was 7.6±1.9 and the total score was 15.1±3.4. The VAS score of the implant specialist group was 6.8±1.8. The repeatability test of the two VAS results in the patient group was not statistically significant (Kappa=0.012, P>0.05); the two VAS results of the implant specialist group and the dentist group both had good repeatability (Kappa=0.727 and 0.556, P<0.01). The VAS score was weakly correlated with the total PES/WES score (r=0.27, P<0.01). The VAS score was correlated with the score elements in PES/WES (P<0.01), and the color (r=0.20) and shape (r=0.22) of the crown were the larger correlation coefficients. The correlation coefficients between the VAS score and the PES/WES scoring system decreased among the implant specialist group (r=0.49, moderate correlation), the dentist group (r=0.25, weak correlation) and the patient group (r=0.12, P>0.05). Conclusions: The consistency of VAS and PES/WES is affected by the cognition of the scorer. The combination of the two scoring systems is feasible and necessary for physicians to evaluate the overall esthetic effect of implant restoration.

[Progress in emergence profile design for implant restorations in the esthetic area].

In the implant restoration of aesthetic area, the contour design of restoration has an important influence on the esthetic effect. The shape of subgingival portion of prosthesis, that is, the emergence profile plays an important role in aesthetic effect and health of the soft tissue. There are few studies on the contour design, indications, influencing factors of the emergence profile of the implant prosthesis. Most of the theoretical support for the contour design of implant restorations comes from the natural teeth restoration, but the design of implant and natural teeth restorations is not the same. This paper mainly reviews the design of emergence profile for implant restorations in the esthetic area, and provides and provides reference for clinical doctors.

[Clinical study on bilamina cortical grafting technique for reconstruction of severely atrophic alveolar ridges in anterior maxillae].

Objective: To evaluate the efficacy and long-term outcome of the bilaminar cortical wall building grafting technique for reconstruction of vertical and horizontal alveolar ridge defects in the esthetic zone. Methods: The retrospective study was conducted between January, 2007 and December, 2015. The sample was composed of 24 patients who received bilaminar cortical wall building augmentation in the esthetic zone in Department of Fourth Clinical Division, Peking University School of Stomatology. The 24 patients (11 female and 13 male) had age of (37.8±13.4) years (20-54 years). A bone block harvested from the lateral aspect of the mandibular ramus was bisected into two cortical laminae, which were then used to reconstruct the buccal and palatal walls of an alveolar ridge defect. The inter-laminar space was filled with particulate autogenous bone and the whole graft was covered with anorganic bone graft and collagen membrane. Bone width and vertical measurements were measured at the time of surgery and reentry surgery. Integration of the graft, implant survival rates and complications were recorded. Results: Overall, 24 patients with 35 sites who were included were followed for (7.1±1.9) years. Graft integration (24/24) and implant survival rates (35/35) were determined as 100%. The average horizontal and vertical bone gain was (6.47±2.46) and (5.01±1.12) mm with resorption rates of 9.0% and 10.9%, respectively. One patient showed soft-tissue dehiscence with peri-implant mucositis were observed 9 years after surgery. More than 1.5 mm of buccal bone plate were observed using cone beam computed tomography. Conclusions: This technique was effective and reliable for three-dimensional reconstruction of severely atrophic alveolar ridges in anterior maxillae. Autogenous graft combined with coverage by allogeneic bone graft and collagen membrane provided successful augmentation with low bone resorption.

[Analysis of risk factors of 19 fractured implants].

Objective: To analyze the incidence and possible risk factors of 19 fractured implants out of 8 468 implants in 3 184 cases. Methods: During the 22-year clinical practice, clinical records of 18 patients with 19 fractured implants in 3 184 cases with 8 468 implants were analyzed to determine the following factors: location of the fractured implants, prosthodontics option, date of implant fracture, dimensions of fractured implants, complications prior to implant fracture and parafunctional habit. An evaluation of fractured implants was performed to identify possible factors that may predispose an implant to a higher risk of fracture. Results: Overall, the average duration of service of the implants was (7.0±4.5) years. Implant fracture occurred in 7 Camlog implants, 7 Nobel replace implants, 3 Ankylos implants and 2 Brånemark implants. No Thommen implant fractures were recorded. Amongst the 19 fractured implants, 8 occurred at the thinnest wall portion of the implant neck, 8 at the end of screw and 3 at the self-tapping thread region. All fractures were observed after functional loading. Furthermore, 9/19 (47.4%) of fractures occurred in the maxilla, indicating similar incidence rates in both arches (P=0.065). Most of fractures (16/19) occurred in the molar region and 18/19 in single implant-supported restorations. Totally 17 cases had received metal occlusal restorations. In 6 cases (35.5%), previous bone destruction apically extending to the level of implant fracture was documented before any clinical signs of fracture. Three fractured implants were removed and simultaneously re-implanted with larger-diameter implants, while the rest of the cases were left to heal, followed by a second-stage surgery. Conclusions: Within the limitation of this analysis, the study demonstrated that appropriate implant-abutment connection design, implant diameter, prosthetic strategy and bone resorption are crucial to the long-term performance of implants. There is no significant difference of fractures rates in both archs.

[Clinical evaluation of socket shield technique in maxillary anterior region].

Objective: To evaluate the preliminary clinical outcome of socket shield technique in maxillary anterior region. Methods: Nine patients were treated with socket shield technique in Peking University School and Hospital of Stomatology from February 2012 to December 2015 were enrolled in this study. Ten implants were placed and restored immediately. After 12-48 months' follow-up (averaged 32 months), the peri-implant hard and soft tissue were clinically evaluated. Results: No implants were lost during the observation period, resulting a cumulate 32-month survival. The pink esthetic score (PES) was 13.5. Mesial and distal bone loss were 0.17 mm and 0.22 mm respectively. Conclusions: To achieve good esthetic results, socket shield technique may be an option for maxillary anterior region immediate implant placement.

Autotransplantation of third molars with completely formed roots into surgically created sockets and fresh extraction sockets: a 10-year comparative study.

The aim of this study was to analyze and compare the long-term clinical outcomes of mature third molar autotransplantation in surgically created sockets and fresh extraction sockets with regard to survival and functional success rates. A total of 65 third molars with completely formed roots were autotransplanted in 60 patients (average age 33.1 years). Thirty-six of the teeth were autotransplanted into surgically created sockets with or without guided bone regeneration (GBR; delayed autotransplantation), while 29 were autotransplanted into fresh extraction sockets (immediate autotransplantation; control group). All patients underwent annual clinical and radiographic examinations (average follow-up 9.9 years, range 7-13 years). The survival rates for the control, GBR, and no GBR groups were 93.1%, 95.2%, and 80.0%, respectively, with no significant differences among the groups. There were no statistically significant differences among the groups with regard to the frequency of inflammatory root resorption or root ankylosis. Age did not influence the clinical outcomes. These results suggest that the autotransplantation of third molars with completely formed roots is effective in both surgically created and fresh extraction sockets and provides a high long-term success rate if cases are selected and treated appropriately.

[Analysis on spatial distribution of tuberculosis in China, 2012-2014].

Objective: To analyze the spatial distribution of the incidence of tuberculosis (TB) in China from 2012 to 2014 and provide evidence for the prevention and control of TB. Methods: The database of TB in China from 2012 to 2014 was established by using geographical information system, the spatial distribution map was drawn, trend analysis and spatial autocorrelation analysis were conducted to explore the spatial distribution pattern of TB and identify hot areas. Results: The trend surface analysis showed that the incidence of TB decreased gradually from the west to the east in China, and the U type curve could reflect the TB distribution from the south to the north; Global spatial autocorrelation analysis showed the 2012-2014 global Moran's I were 0.366, 0.364 and 0.358 (P<0.01), suggesting that the incidence of TB had a spatial clustering in China; Local Getis-OrdG(i) spatial autocorrelation analysis by ArcGIS software showed that there was 11 cluster areas, 3 high incidence areas (Xinjiang, Tibet, Qinghai) and 8 low incidence areas (Beijing, Tianjin, Shanghai, Hebei, Inner Mongolia, Shanxi, Shandong, Jiangsu). Conclusion: The incidence of TB had obviously spatial clustering characteristic, the areas at high risk were mainly in the northwestern and plateau area in China.

[Using the Tabu-search-algorithm-based Bayesian network to analyze the risk factors of coronary heart diseases].

Under the available data gathered from a coronary study questionnaires with 10 792 cases, this article constructs a Bayesian network model based on the tabu search algorithm and calculates the conditional probability of each node, using the Maximum-likelihood. Pros and cons of the Bayesian network model are evaluated to compare against the logistic regression model in the analysis of coronary factors. Applicability of this network model in clinical study is also investigated. Results show that Bayesian network model can reveal the complex correlations among influencing factors on the coronary and the relationship with coronary heart diseases. Bayesian network model seems promising and more practical than the logistic regression model in analyzing the influencing factors of coronary heart disease.

Screening diabetes in tuberculosis patients in eastern rural China: a community-based cross-sectional study.

OBJECTIVES: To understand the prevalence of diabetes mellitus (DM) and tuberculosis (TB) comorbidity in rural China and to identify factors associated with TB-DM comorbidity and screening efficacy. METHODS: A community-based cross-sectional study was carried out in four counties in eastern rural China. All TB patients newly registered from April 2013 to March 2014 were screened for DM using fasting blood glucose (FBG). Screening-positive patients were further examined using glycosylated haemoglobin A1C (HbA1c). RESULTS: Ninety-seven (7.7%) of the 1252 recruited TB patients had DM, 44 (45.4%) of whom were newly diagnosed. The DM-TB patients were significantly older than non-diabetics (mean age 57 ± 13 years vs. 49 ± 19 years, P < 0.001). The risk of DM-TB was higher in patients aged >40 years (OR 3.039) and in overweight patients (OR 2.595). The number needed to screen (NNS) among TB patients to identify one case of DM was 12.97. The NNS to identify one new DM patient (27.4) was lower in participants aged >40 years (20.5), those who were illiterate (19.9), those with a family history of DM (9.3), those with missing bacille Calmette-Guérin vaccination (11.3), current smokers (14.2) and those with body mass index >24 (11.4). CONCLUSION: Regular DM screening in TB patients is practical in rural China. Better efficacy of DM-TB detection could be obtained by screening high-risk populations, such as overweight TB patients or those with a family history of DM.

A smoking cessation intervention among tuberculosis patients in rural China.

OBJECTIVE: To assess the integration of a smoking cessation intervention into routine tuberculosis (TB) services. METHOD: Consecutive TB patients registered from 1 March to 31 August 2010 were enrolled in an intervention for self-reported smoking to promote tobacco cessation during treatment for TB. Information on the harmful health effects of tobacco smoke and smoking and TB were provided to TB patients who self-reported as current smokers. Smoking status was reassessed at every follow-up visit during anti-tuberculosis treatment with reinforced health messages and advice to quit. RESULTS: Of 800 TB patients enrolled, 572 (71.5%) were male and 244 (30.5%) were current smokers. Females were more likely to be non-smokers (100% vs. 35.8%, P < 0.001). Of the 244 current smokers, 144 (59.0%) started smoking at <20 years, 197 (80.7%) consumed ⩾20 cigarettes per day, 211 (86.5%) had perceived smoking dependence and 199 (81.6%) had made no attempt to quit before the diagnosis of TB. Of the 244 current smokers, 234 (95.9%) were willing to quit, and 156 (66.7%) reported abstinence at month 6. Challenges to implementing smoking cessation intervention were identified. CONCLUSION: The majority of current smokers among TB patients were willing to quit and remained abstinent at the end of anti-tuberculosis treatment. This intervention should be scaled up nationwide.

Objectif : Evaluer la possibilité d'intégrer une intervention d'arrêt du tabac dans les services de routine de la tuberculose (TB).Méthode : Les patients tuberculeux consécutifs inscrits entre le 1e mars et le 31 août 2010 ont été enrôlés dans une intervention visant à promouvoir l'arrêt du tabac chez ceux qui disaient fumer pendant le traitement de leur TB. Des informations sur les effets sanitaires dangereux de la fumée de tabac et sur le fait de fumer en étant tuberculeux ont été fournies aux patients qui se sont dit fumeurs actuels. Le statut en matière de tabac a été réévalué à chaque visite de suivi pendant le traitement antituberculeux avec des messages sanitaires renforcés et des conseils visant à l'arrêt.Résultats : Sur 800 patients TB enrôlés, 572 (71,5%) étaient des hommes et 244 (30,5%) étaient des fumeurs actuels. Les femmes étaient plus souvent non fumeuses (100% contre 35,8% ; P < 0,001). Des 244 fumeurs actuels, 144 (59,0%) avaient commencé à fumer avant 20 ans, 197 (80,7%) consommaient ⩾20 cigarettes par jour, 211 (86,5%) étaient conscients de leur dépendance au tabac et 199 (81,6%) n'avaient jamais essayé d'arrêter avant le diagnostic de TB. Des 244 fumeurs actuels, 234 (95,9%) voulaient arrêter et 156 (66,7%) ont déclaré être toujours abstinents à 6 mois. Les défis à la mise en œuvre d'une intervention d'arrêt du tabac ont été identifiés.Conclusion : La majorité des fumeurs actuels parmi les patients TB voulaient arrêter et sont restés abstinents à la fin du traitement antituberculeux. Cette intervention devrait être étendue au pays tout entier.

Objetivo: Evaluar la utilidad de la integración de las intervenciones de promoción del abandono del tabaquismo en los servicios ordinarios de atención de la tuberculosis (TB).Métodos: Se inscribieron de manera consecutiva los pacientes con diagnóstico de TB y tabaquismo actual del 1° de marzo al 31 de agosto del 2010 en una intervención cuyo objeto era a promover el abandono del hábito tabáquico durante el tratamiento antituberculoso. Se suministró información acerca de los efectos deletéreos del humo del tabaco sobre la salud y de la asociación del tabaquismo y la TB a los pacientes que autorrefirieron un tabaquismo actual. En cada consulta de seguimiento durante el tratamiento se evaluó de nuevo la situación frente al tabaco, se reforzaron los mensajes sobre la salud y se reiteró el consejo de abandonar el hábito.Resultados: De los 800 pacientes con TB inscritos, 572 fueron de sexo masculino (71,5%) y 244 eran fumadores actuales (30,5%). Las mujeres fueron con mayor frecuencia no fumadoras (100% contra 35,8%; P < 0,001). De los 244 fumadores actuales, 144 habían comenzado a fumar antes de los 20 años de edad (59,0%), 197 consumían ⩾20 cigarrillos por día (80,7%), 211 habían percibido la dependencia al tabaquismo (86,5%) y 199 nunca habían intentado abandonar el hábito antes del diagnóstico de TB (81,6%). De los 244 fumadores actuales, 234 estaban dispuestos a abandonar el tabaco (95,9%) y 156 notificaron abstinencia al sexto mes (66,7%). Se pusieron de manifiesto obstáculos a la aplicación de la intervención en favor del abandono del tabaquismo.Conclusión: En su mayoría, los fumadores actuales entre los pacientes con diagnóstico reciente de TB estaban dispuestos a abandonar el tabaquismo y cumplieron con la abstinencia hasta el final del tratamiento antituberculoso. Se debería ampliar la aplicación de esta intervención a escala nacional.