Objective: To identify the role of Tribbles pseudokinase 3 (TRIB3) during the process of adipogenic differentiation of human adipose-derived mesenchymal stem cells (hASCs), and to provide a new target and a novel idea for the application of hASCs in adipose tissue engineering and soft tissue regeneration. Methods: TRIB3-knockdown hASCs (shTRIB3) and TRIB3-overexpression hASCs (TRIB3-over) were established using lentivirus transfection technique. The transfection effect was estimated by the visible presence of green fluorescence as the expression of green fluorescent protein (GFP) in the transfected hASCs. The lentiviral transfection efficiency was examined by quantitative real-time poly-merase chain reaction (qRT-PCR) and Western blot. After adipogenic induction, Oil Red staining and quantification, as well as qRT-PCR about several specific adipogenic markers were used to evaluate the adipogenic differentiation ability of hASCs. Results: In TRIB3-knockdown hASCs, the TRIB3 mRNA expression level decreased by about 84.3% compared with the control group (P<0.01), and the TRIB3 protein level also showed obvious reduction. Oppositely, in TRIB3-overexpression hASCs, the TRIB3 mRNA expression level increased by approximately 160% compared with the control group (P<0.01), and the TRIB3 protein level also showed a significant increase. These results indicated a successful construction of TRIB3-knockdown hASCs and TRIB3-overexpression hASCs. The Oil Red staining results showed that the down-regulation of TRIB3 significantly promoted lipid droplets formation in hASCs, consistent with Oil Red quantification. On the other hand, the up-regulation of TRIB3 suppressed lipid droplets formation in hASCs, consistent with Oil Red quantification. After adipogenic induction, adipogenesis-related genes, including peroxisome proliferator-activated receptor γ (PPARγ), cluster of differentiation 36 (CD36) and CCAAT/enhancer binding protein α (C/EBPα), were increased significantly in TRIB3-knockdown hASCs compared with the control group (P<0.01). Oppositely, PPARγ, CD36 and lipoprotein lipase (LPL) were significantly decreased in TRIB3-overexpression hASCs compared with the control group (P<0.01). Conclusion: TRIB3 inhibited the adipogenic differentiation of hASCs. Knockdown of TRIB3 promoted the ability of adipogenesis of hASCs, while overexpression of TRIB3 inhibited the adipogenic differentiation of hASCs. Considering the important role of PPARγ in the adipogenis process, the molecular mechanism of the regulatory function of TRIB3 may be related with PPARγ signal pathway.

Objective: To prepare glycol-chitosan (GC)-based single /dual-network hydrogels with different composition ratios (GC31, DN3131 and DN6262) and to investigate the effects of hydrogel scaffolds on biological behavior of human dental pulp cell (hDPC) encapsulated. Methods: GC-based single-network hydrogels (GC31) and GC-based dual-network hydrogels (DN3131, DN6262) with different composition ratios were prepared. The injectability was defined as the average time needed to expel a certain volume of hydrogel under a constant force. The degradation of the hydrogel was determined by the weight loss with time. The fracture stress was measured using a universal testing machine. The proliferation of hDPCs in hydrogels was detected using the cell counting kit-8 (CCK-8) method and Calcein-AM/PI Live/Dead assay. After 14 days of odontoblastic induction, the expression of alkaline phosphatase (ALP), dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) was detected by real-time quantitative reverse transcription PCR (real-time RT-PCR) and the mineralized nodules was observed by Von Kossa staining. Results: The injectability of all three groups of hydrogels was acceptable. The time of injection of GC31 was the shortest, and that of DN6262 was longer than DN3131 (P<0.05). The degradation rate of GC31 hydrogel in vitro was significantly faster than that of the dual-network hydrogel groups (P<0.05). There was no significant difference between DN3131 and DN6262 (P>0.05). The compressive resistance failure point of GC31 group was 1.10 kPa, while it was 7.33 kPa and 43.30 kPa for DN3131 and DN6262. The compressive strength of dual-network hydrogel was significantly enhanced compared with single-network hydrogel. hDPCs were in continuous proliferation in all the three groups,and the GC31 group showed a higher proliferation rate (P<0.05). The expression levels of DSPP, DMP-1 and ALP in the dual-network hydrogel groups (DN3131, DN6262) were significantly higher than that of GC31 after culturing for 14 days (P<0.05), there was no difference in the expression levels of DMP-1 and ALP between DN3131 and DN6262 (P>0.05); Von Kossa staining showed that more mineralization deposition and mass-shaped mineralized nodules formed in DN3131 and DN6262, while only light brown calcium deposition staining was observed in GC31 group, which was scattered in granular forms. Conclusion: GC-based single/dual network hydrogels with different composition ratios met the injectable requirements. GC31 group had a lower mechanical properties, in which hDPCs exhibited a higher proliferation rate. Dual-network hydrogels had slower degradation rate and higher mechanical properties, in which hDPCs exhibited better odontoblastic differentiation potential and mineralization potential.

Objective: To investigate the expression changes of the epigenetic regulator enhancer of zeste homolog 2 (EZH2) during pulp inflammation and the effect of EZH2 on macrophages migration. Methods: Rat dental pulp was stimulated with 10 g/L lipopolysaccharide (LPS) to establish a model of rat pulpitis at different stages of inflammation. Immunohistochemical staining was used to detect the expression changes of EZH2 during the progression of pulp inflammation. Immunofluorescence double stain-ing was used to detect the expression of EZH2, CD68 and their colocalization. To screen the appropriate concentration of EZH2 recombinant protein to stimulate hDPCs and human leukaemia-derived monocytic cell line (THP-1) cells,the effects of different concentrations (1, 10, 20, 40, and 100 μg/L) of EZH2 recombinant protein on proliferation of human dental pulp cells (hDPCs) and human monocyte cell line THP-1 were detected by cell counting kit-8 (CCK-8). Transwell migration assay was used to detect the effect of supernatants of hDPCs treated with EZH2 recombinant protein on the migration of THP-1 cells. Results: HE staining results showed that in the model of rat pulp inflammation induced by LPS, with the prolongation of LPS stimulation, the inflammation response of pulp gradually increased. Immunohistochemical results showed that EZH2 expression decreased within 8 h of LPS-induced dental pulp inflammation; but after 1, 3, and 7 d of stimulation, EZH2 expression gradually increased with the extension of the stimulation time. As for the normal rat dental pulp tissue, the positive expression of EZH2 was scattered in the odontoblast cell layer and the pulp proper. Compared with the control group, LPS stimulated the expression of EZH2 and CD68 in the infected dental pulp, and the colocalization of EZH2 and CD68 could be detected in macrophages. The results of CCK-8 suggested that the appropriate concentration of EZH2 recombinant protein to stimulate hDPCs and THP-1 cells was 20 μg/L. Transwell cell migration assay confirmed that compared with the supernatant of EZH2 untreated HDPCs group, the supernatant of EZH2-treated hDPCs significantly promoted macrophage chemotaxis. Conclusion: EZH2 is involved in the development of pulpitis and promotes the chemotaxis of macrophages, which suggests that EZH2 may play an important regulatory role in the development of pulp inflammation.

Objective: To study the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on anti-inflammation and repair of human dental pulp cells (hDPCs). Methods: Primary hDPCs from the freshly extracted human third molars were cultured and passaged in vitro, and the following experiments were performed using the 4th-6th generations of hDPCs. HDPCs were cultured in Dulbecco’s modified eagle medium (DMEM) containing 1 mg/L lipopolysaccharide (LPS) to obtain LPS irritated hDPCs (LPS-hDPCs), which served as the inflammatory positive group. LPS-hDPCs in the experimental group were cultured in DMEM containing different concentrations (1, 10, and 100 μmol/L) of NSAIDs (aspirin or meloxicam). HDPCs cultured in DMEM were used as the negative control group. The effects of NSAIDs on the proliferation of hDPCs were assessed on the 1st, 3rd, 5th, and 7th day by MTT assay. The effects of NSAIDs on the expression of inflammation related genes interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) of LPS-hDPCs were detected at the 6th hour by real-time PCR. The expression of diffe-rentiation related markers dentin matrix protein-1 (DMP-1) and dentin sialophosphoprotein (DSPP) were detected on the 7th day by real-time PCR. The effects of NSAIDs on the mineralization of LPS-hDPCs were assesd on the 14th day by alizarin red staining. Calcium mineralized nodules were semi-quantitatively determined by cetyl pyridine chloride. Results: MTT assay showed that 1-100 μmol/L aspirin or meloxicam significantly promoted the proliferation of hDPC in a concentration dependent manner (P<0.05). Real-time PCR showed that 1-100 μmol/L meloxicam or 100 μmol/L aspirin down-regulated significantly the mRNA expression of TNF-α and IL-6 of LPS-hDPCs (P<0.05), and 100 μmol/L meloxicam down-regulated IL-6 and TNF-α more significantly than 100 μmol/L aspirin of LPS-hDPCs (P<0.05). Real-time PCR showed that 100 μmol/L meloxicam up-regulated the mRNA expression of DMP-1 and DSPP of LPS-hDPCs significantly (P<0.05). Alizarin red staining showed the meloxicam at the concentration of 100 μmol/L significantly promoted the mineralization of LPS-hDPCs (P<0.05). Conclusion: In this study, meloxicam promoted the proliferation of hDPCs, inhibited the inflammatory reaction and promoted differentiation and mineralization of hDPCs under LPS irritation. The present results suggest that meloxicam may play a role in anti-inflammation and repair of pulp inflammation.

Objective: To investigate the incidence and clinicopathologic features of cervical lymph node metastasis in salivary gland adenoid cystic carcinoma (AdCC). Methods: Retrospective analysis was made in 798 AdCC patients who underwent tumor resection during January, 2001 to January, 2019 in Peking University School and Hospital of Stomatology, especially the clincopathologic characteristics of 82 cases with lymph node metastasis. Results: In the study, 82 of the 798 patients were identified with cervical lymph node metastasis, which was confirmed by histopathological examination. The palate, the region of sublingual gland and mouth floor, and the parotid were the frequently involved primary sites for AdCCs. The general incidence rate of lymph node metastasis was approximately 10%. The submandibular gland, the region of sublingual gland and mouth floor, and the mobile tongue were the most frequent sites of lymph node metastasis with the incidence rates of 20.8%, 16.1%, and 15.1%, respectively; while lymph node metastasis was uncommon in the tumors which were the origin from the palate and parotid, with incidence rates of 6.1% and 3.4%, respectively. Most AdCC cases (70.7%) showed the classic “tunnel-style” metastatic pattern of occurrence, and the level Ⅰ and Ⅱ regions were the most frequently involved areas. The 5-year and 10-year overall survival rates of the patients with lymph node metastasis were 77.4% and 20.6% respectively, while the 5-year and 10-year overall survival rates of the patients with no lymph node metastasis were 83.5% and 57.6%, respectively. The univariate analysis demonstrated that statistically significant differences in the overall survival for the presence of lymph node metastasis (P<0.001). In the meantime, the 5-year disease-free survival rate of the patients with lymph node metastasis also showed statistically significant differences to that of the AdCC patients with no lymph node metastasis. In addition, the primary site and histological grade were significantly associated with lymph node metastasis, and the high-grade solid growth pattern was identified as a strong predictor for the occurrence of lymph node metastasis. Conclusion: Cervical lymph node metastasis has a high tendency of occurrence in submandibular gland and tongue-mouth floor complex, and the high-grade solid growth pattern could be taken as a strong predictor for the occurrence of lymph node metastasis, which correlates to poor prognosis of AdCC patients. A selective neck dissection should be considered as a ma-nagement in such patients.

Objective: To investigate the clinicopathologic features and prognostic factors in odontoge-nic keratocyst (OKC), and to provide new reference for clinic treatment and management of these patients. Methods: Clinicopathological data of 844 cases initially diagnosed as or associated with OKC at Department of Oral Pathology, Peking University Hospital of Stomatology from 2000 to 2018 were collec-ted. The cases were divided into 4 groups: sporadic OKCs (intraosseous, cystic lesion irrelevant to nevoid basal cell carcinoma syndrome), syndromic OKCs, solid OKCs and peripheral OKCs. The patients were follow-up for 6 to 216 months and the factors that might relate to recurrence were analyzed. Results: There were 805 cases (95.4%) of sporadic OKCs, 32 cases (3.8%) of syndromic OKCs, 3 cases of solid OKCs and 4 cases of peripheral OKCs. The main age of sporadic OKCs was 36.03 years with the peak at the second and third decades. Ratio of male and female was 1.27 ∶1. The predilection site was the molar and ramus area of mandibular (56.2%). In the study, 428 cases (71.2%) were unilocular in radiography while 28.8% were multilocular. The recurrent rate of enucleation with the follow-up was 20.1% (118/588) while most of them occurred in 1-3 years after surgery. The recurrent rate of multilocular patients (39.0%) was significantly higher than that of the unilocular. Enucleation after marsu-pialization (43 cases) or enucleation only (545 cases) showed no difference in recurrence (P>0.05). The syndromic OKCs was younger (main 20.97) and preferred to be multiple compared with sporadic OKCs (30/32, 93.7%). The predilection site was also molar and ramus area of mandibular (41.7%). Age and gender distribution of multiple cases had no significant difference with those in sporadic OKCs. More daughter cysts and epithelial islands were seen (56.3% and 17.9%). Furthermore, the recurrent rate was significantly higher than that of the sporadic OKCs (13/29, 44.9%). But there was no evidence of recurrent-related factors. The age of solid and peripheral OKCs, averaged at 45.00 and 65.75 years, were older than others. Four of peripheral OKCs showed no recurrence after enucleation. Conclusion: The recurrence rate of sporadic OKCs after enucleation is 20.1%. The multilocular lesions prefer to be recurrent. There is no significant difference of recurrence with enucleation only or enucleation after marsupialization. Compared with sporadic OKCs, the syndromic patients are younger and easier to be multiple. It tends to be recurrent frequently and rapidly. There are no related factors about recurrence of syndromic patients. The clinicians should considerate comprehensively and make an individual management of therapy and follow-up. Solid and peripheral OKCs are rare and older.

Objective: To evaluate the uptake of exosomes by stem cells from apical papilla (SCAP), thus to provide experimental basis for mechanism of the exosomes endocytosis by SCAP. Methods: (1) Exosomes of dental pulp stem cells (DPSCs) were isolated by hypercentrifugation combined with ultrafiltration method. The exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis and western blot. (2) PKH-26 membrane labeling technology was used to mark the DPSCs derived exosomes. The labeled exosomes were co-cultured with SCAP at 37 ℃ as positive control group, and co-cultured with SCAP at 4 ℃ as the low-temperature treatment group, while the negative control group was set up. (3) Using clathrin-mediated endocytosis inhibitor chlorpromazine (CPZ, 10 μmol /L) as CPZ group, caveolae-mediated endocytosis Genistein (200 μmol/L) as Genistein group, and macropinocytosis inhibitor LY294002 (50 μmol/L) as LY294002 group to treat the SCAP respectively. Solvent control group (DMSO group) was set. Immunofluorescence staining was used to detect the red fluore-scence SCAP and flow cytometry was used to analyze the proportion of SCAP labeled with red fluore-scence. Results: (1) The bilayer membrane and cup-shaped appearance of representative exosomes were observed. The peak of the size of DPSCs-derived exosomes was at 144 nm. The exosomes expressed exosomal marker proteins TSG101 and CD63, but not GAPDH which was the cellular internal control protein. (2) Immunofluorescence staining showed that after being co-cultured at 37 ℃ for 6 hours, red fluorescence could be detected in SCAP but it could not be detected after being co-cultured at 4 ℃ for 6 hours. After endocytosis inhibition, the red fluorescence in SCAP was reduced. Flow cytometry showed that the proportion of SCAP labeled with red fluorescence in positive group was 35.0%, in negative control group was 0.5%,and in solvent control group was 29.7%, in CPZ group, Genistein group and Genistein group were reduced to 13.7%, 16.6%, and 20.9%, respectively. Conclusion: SCAP could uptake the DPSCs derived exosomes, and low temperature could inhibit this process. The exosomes uptake of SCAP was mediated by the clathrin endocytosis pathway, caveolae-mediated endocytosis and macropinocytosis pathway.

Objective: To compare the orofacial pain sensitivity with operant test and mechanical hyperalgesia with von Frey filaments of two orofacial pain models (EOI: experimental occlusal interference; pIONX: partial infraorbital nerve transection). To investigate the operant and evoked characteristics of EOI-rats. Methods: The orofacial operant behaviors were tested by Ugo Basile Orofacial Stimulation Test System. The mechanical thresholds of vibrissal pads were tested by von Frey filaments. Male Sprague-Dawley rats were randomly divided into eight groups: von Frey group: sham-EOI, EOI, sham-pIONX, pIONX (sham: sham-operated group); operant test group: sham-EOI, EOI, sham-pIONX, pIONX (sham: sham-operated group). The mechanical thresholds and orofacial operant behaviors were tested on pre-operation and post-operation days l, 3, 7, 10, 14 and 21. Results: In pIONX of von Frey group, the mechanical withdrawal threshold decreased from days 1 to 21 (P<0.05), peaking from days 7 to 10, and lasted until the end of the experiment. There was no significant difference between the bilateral sides. In pIONX of operant test group, the total contact time decreased from days 10 to 21 (P<0.05), peaking from days 10 to 14, and lasted until the end of the experiment. In EOI of von Frey group, the mechanical withdrawal threshold decreased from days 3 to 21 (P<0.05), peaking on day 7, and lasted until the end of the experiment. There was no significant difference between the bilateral sides. In EOI of operant test group, the total contact time decreased from days 1 to 21 (P<0.05), peaking from days 7 to 10, and lasting until the end of experiment. Conclusion: Orofacial operant test is a stable method to evaluate orofacial pain behaviors, which could discriminate the feature of neuropathic and EOI orofacial pain. In these two animal models, both of the operant behaviors and the mechanical hyperalgesia exhibited different time courses. Orofacial operant test provides a novel method for evaluating the orofacial pain sensitivity and studying the orofacial pain mechanism thoroughly.

Objective: To evaluate the short-term outcome of regenerative surgery for peri-implantitis therapy. Methods: From March 2018 to January 2019, 9 patients with 10 implants who suffered from peri-implantitis were included in the present research. Vertical bone defect at least 3mm in depth with 2 or more residual bone walls was confirmed around each implant by radiographic examination. Restorations were replaced by healing abutments on 3 implants with the consent of the patients. Guided bone regeneration surgery was performed after a hygienic phase. During surgery, full thickness flaps were elevated on both buccal and lingual aspects. Titanium curette was used for inflammatory granulation tissue removal and implant surface cleaning. The implant surface was decontaminated by chemical rinsing with 3% hydrogen peroxide solution. After being thoroughly rinsed with saline,the bone substitutes were placed in bone defects which were covered by collagen membranes. 6 months after non-submerged healing, the clinical parameters including peri-implant probing depth (PD, distance between pocket bottom and peri-implant soft tissue margin) and radiographic bone level (BL, distance form implant shoulder to the first bone-to-implant contact) were used to evaluate the regenerative outcome. PD was measured at six sites (mesial, middle and distal sites at both buccal and lingual aspects) around each implant, and BL was measured at the mesial and distal surfaces of each implant on a periapical radiograph. Results: The deepest PD and largest BL of each implant ranged from 6-10 mm and 3.2-8.3 mm respectively. All the implants healed uneventfully after surgery. The mean peri-implant PD at baseline and 6 months after surgery were (6.2±1.4) mm and (3.1±0.6) mm respectively, and a mean (3.0±1.5) mm radiographic bone gain was observed, P<0.01. Treatment success was defined as: no sites with residual PD≥6 mm, no bleeding on probing, and BL elevation of at least 1 mm. Nine implants from 8 patients fulfilled the success criteria. Residual pockets with 6 mm in depth and bleeding on probing could be detected in only one implant. Conclusion: Within the limitation of the present research, guided bone regeneration surgery can be used for the treatment of bone defect that resulted from peri-implantitis. Significant PD reduction and radiographic bone gain can be obtained after 6 months observation.

Objective:To compare the clinical effects of ultrasonic subgingival debridement and ultrasonic subgingival debridement combined with manual root planing on severe periodontitis and then to investigate the necessity and significance of manual root planing. Methods: Twenty-three patients with severe periodontitis participated in this split-mouth randomized-controlled clinical trial. Baseline examination and randomization were performed after supragingival scaling: each of the upper and lower jaws had a quadrant as the test group treated with ultrasonic subgingival debridement combined with manual root planing, whereas the other two quadrants were the control group treated with ultrasonic subgingival debridement. Treatment of each patient was at intervals of one week and completed in two visits. Clinical indicators concerning probing depth (PD), clinical attachment loss (CAL) and bleeding index (BI) were recorded at baseline and 1 month, 3 months, 6 months after treatment. Results: There was no significant difference of periodontal indicators between the test group and the control group at baseline. Both the test group and control group resulted in significant improvement of PD, CAL and BI. One and three months after treatment, reduction of PD in the test group was higher than that in the control group [1 month: (2.13±1.31) mm vs. (1.79±1.33) mm, P<0.01; 3 months: (2.46±1.33) mm vs. (2.17±1.38) mm, P<0.01] and reduction of CAL in the test group was higher than that in the control group [1 month: (1.89±2.03) mm vs. (1.65±1.93) mm, P<0.01; 3 months: (2.03±2.05) mm vs. (1.83±1.97) mm, P<0.05]. Six months after treatment, PD in the test group and the control group decreased by (2.52±1.40) mm and (2.35±1.37) mm respectively, and the improvement in the test group was significantly better than that in the control group (P<0.01). CAL in the test group and the control group decreased by (1.89±2.14) mm and (1.77±2.00) mm respectively, and there was no statistical difference between the groups. There was no significant difference in the changes of BI between the two groups 1, 3 and 6 months after treatment. Conclusion: Ultrasonic subgingival debridement combined with manual root planing has more reduction in PD and CAL compared with ultrasonic subgingival debridement. Therefore, it is still necessary to use manual instruments for root planing following ultrasonic subgingival debridement.

Objective: To investigate the associations of impaired glucose metabolism and insulin resis-tance with chronic periodontitis in pre-diabetes patients. Methods: A cross-sectional analysis was conducted and we included a total of 171 pre-diabetes patients aged 30-65 years, free of diabetes. Pre-diabetes was defined as impaired fasting glucose (IFG) [fasting glucose (FG): 6.1-7.0 mmol/L] and/or impaired glucose tolerance (IGT) [oral glucose tolerance test (OGTT): 7.8-11.0 mmol/L]. Chronic periodontitis was defined according to Centers for Disease Control and Prevention (CDC)/American Academy of Periodontology (AAP) definition and the patients were divided into mild, moderate, and severe chronic periodontitis groups [mild: at least two interproximal sites with clinical attachment loss (CAL) ≥3 mm and at least two interproxima sites with probing depth (PD) ≥4 mm or 1 site with PD≥5 mm; moderate: at least two interproximal sites with CAL ≥4 mm and at least two interproxima sites with at least two interproximal sites with PD ≥5 mm; severe: at least two interproximal sites with CAL ≥6 mm and at least one interproxima site with at least two interproximal sites with PD≥5 mm]. A periodontal examination indexes [plaque index (PLI), PD, CAL, and bleeding on probing (BOP)] and glucose metabolism indexes [FG, OGTT, hemoglobinA1c (HbA1c), fasting insulin and homeostasis model assessments of insulin resistance (HOMA-IR)] were measured. The association of glucose meta-bolism and chronic periodontitis was investigated by multivariable logistic regression analysis. Results: FG in the moderate and severe chronic periodontitis groups was significantly higher compared with mild chronic periodontitis group, HOMA-IR in the moderate and severe chronic periodontitis groups was signi-ficantly higher compared with mild chronic periodontitis group, OGTT in the severe chronic periodntitis group was significantly higher compared with mild chronic peridontitis group and moderate chronic pe-riodontitis groups, and there was no significant difference between moderate and mild chronic periodontitis groups. For the insulin and HbA1c, there was no significant difference among mild, moderate and severe chronic periodontitis groups. After multivariable adjustment of age, gender, smoking status, hypertension and body mass index, IFG (OR=1.39, 95%CI: 1.01-1.98) and HOMA-IR (OR=1.36, 95%CI: 1.04-1.76) were associated with moderate periodontitis; IFG (OR=1.64, 95%CI: 1.17-2.40), IGT (OR=1.65, 95%CI: 1.21-2.26), and HOMA-IR (OR=1.72, 95%CI: 1.23-2.41) were significantly associated with severe periodontitis. Conclusion: Our data provided evidences that impaired glucose metabolism were associated with chronic periodontitis among pre-diabetes patients.

Objective: To measure the distance from cemento-enamel junction (CEJ) to alveolar crest (AC) of labial side of anterior teeth on skeletal Angle class Ⅲ patients under direct vision during periodontal bone augmentation surgery and to make relevant analysis to find the relevant factors. Methods: In the study, 46 skeletal Angle class Ⅲ patients (10 males and 36 females) received periodontal bone augmentation surgery of anterior teeth were included, with 67 jaws (27 maxillae and 40 mandibles) and 400 anterior teeth (161 maxillary anterior teeth and 239 mandibular anterior teeth). The mean age was 23.65 years. Maxillary anterior teeth consisted of 54 central incisors, 53 lateral incisors and 54 canines. Mandibular anterior teeth consisted of 79 central incisors, 80 lateral incisors and 80 canines. CEJ-AC was measured in three sites (mesial sites, central sites and distal sites) by Williams periodontal probes during periodontal bone augmentation surgery under direct vision by the same researcher. Results: The average CEJ-AC of 400 anterior teeth was (2.21±1.48) mm. The average CEJ-AC of maxillary anterior teeth was (1.72±1.13) mm, more than (2.54±1.60) mm of mandibular anterior teeth (P<0.05). The average CEJ-AC of canines was (2.42±1.78) mm, more than (2.06±1.27) mm of central incisors or (2.16±1.32) mm of lateral incisors (P<0.05). The average CEJ-AC of central sites was (3.04±2.01) mm, more than (1.79±0.86) mm of mesial sites or (1.81±0.89) mm of distal sites (P<0.05). CEJ-AC of 233 anterior teeth was more than 2 mm, accounting for 58.25%, and 117 anterior teeth with dehiscence were found, accounting for 29.25%. Multilevel and multivariate Logistic regression showed age, jaw, tooth and site were the relevant factors to the position of alveolar crest. Conclusion: The position of alveolar crest of skeletal Angle class Ⅲ patients who received periodontal bone augmentation surgery was lower than that of the general population, causing periodontal risks during decompensation orthodontics therapy before orthognathic surgery. The position of alveolar crest was lower in older patients than in younger patients, in mandibular teeth than in maxillary teeth, in canines than in central incisors or lateral incisors, and in central sites than in mesial sites or distal sites of labial side, which showed much higher risk.

Objective: To establish a Parotid Imaging Reporting and Data System (PI-RADS) for CT diagnosis of the parotid gland neoplasms and to investigate the clinical applicable value and feasibility of PI-RADS. Methods: Patients who had been diagnosed with primary parotid gland neoplasms and had received surgical treatments in Peking University School and Hospital of Stomatology during the period of January 2013 to December 2016 were included in this study. The diagnoses were confirmed by the postoperative pathological examinations in all the patients. The CT imaging data of all patients were retrospectively reviewed and analyzed by two readers in consensus. Imaging characteristics related to the parotid neoplasms were extracted and quantified. Based on comprehensive analysis of the imaging characteristics, the probabilities of the benign and malignant neoplasms were evaluated and classified into six grades, PI-RADS 1-6 (PI-RADS 1: normal parotid gland; PI-RADS 2: confidently benign lesions; PI-RADS 3: probably benign lesions without confirmed evidence of malignancy; PI-RADS 4: suspected malignancy without sufficient evidence of malignancy; PI-RADS 5: confidently malignant lesions; PI-RADS 6: lesions with confirmed pathological evidence of malignancy). Results: A total of 897 patients with 1 003 parotid lesions were included. The lesions included 905 benign and 98 malignant lesions. The proportions of the malignancies in PI-RADS 2, PI-RADS 3, PI-RADS 4 and PI-RADS 5 according to the two readers in consensus were 0.4%, 5.7%, 35.5% and 96.7% respectively. The overall Cohen’s Kappa test showed medium consistency between the two independent researchers (κ=0.614, P<0.001, 95%CI: 0.569-0.695). Pearson Chi-square test showed that the proportions of malignancies increased with the diagnostic PI-RADS grades (Cochran-Armitage trend test, Z=-15.579, P<0.001). The results of Pearson Chi-square tests showed significant differences between the grades [PI-RADS 2 and 3 (χ ²=12.048, P=0.001); PI-RADS 3 and 4 (χ ²=75.231, P<0.001); PI-RADS 4 and 5 (χ ²=32.266, P<0.001)]. Conclusion: PI-RADS can be used to evaluate the risk of malignancy and will be helpful to improve the imaging diagnosis and clinical treatment of paro-tid gland neoplasms.

Objective: There is no universally accepted method for determining the ideal sagittal position of the maxilla in orthognathic surgery. The purpose of this study was to compare how well the Delaire’s cephalometric analysis correlated with postoperatively findings in patients who underwent orthognathic surgery planned using other cephalometric analyses,as well as to evaluate the feasibility of the Delaire’s cephalometric analysis in predicting the ideal sagittal position of the maxilla and chin. Methods: In the study, 35 patients with skeletal Class Ⅲ malocclusion were involved and met the criteria. Treatment plans were developed using photographs, 3-D photographs,radiographs, and standard cephalometric measurements. The Delaire’s cephalometric analysis data, like the phase measurements (∠C1-L1 and ∠C1-L2) of the sagittal positions of the maxillary and the chin separating the reference line (L1) of NP point and the reference line (L2) of Me point, were analyzed using Dolphin Imaging software. At the same time, the analyses on standard measurements were also performed. Four orthognathic doctors, 4 orthodontic doctors and 4 college students from non-medical majors were selected as aesthetic evaluators to assess the patients’ profile aesthetic by visual analogue scale (VAS). The results through the Delaire’s cephalometric analysis were statistically compared with that through standard methods. Results: The mean of ∠C1-L1 was 83.93°±2.99°and∠C1-L2 was 89.08°±2.48° for males postoperatively, and 85.67°±3.60° and 88.30°±4.20°for females postoperatively. Compared with the reference values of Chinese good-looking people, there was no significant difference of NP point, whereas there was a significant difference of Me point. The postoperative aesthetic scores were: the mean was 6.71±0.25 of upper jaws, 6.81±0.30 of chins and 6.90±0.29 of the overall for males; and 7.19±0.22, 7.26±0.34 and 7.39±0.29 for females. Compared with preoperative scores, there was a significant improvement. Furthermore, the scores of chins and the overall scores were related to the sagittal position of the chins. Conclusion: Compared with standard cephalometric analysis, the Deliare’s cephalometric analysis well unravel the preoperative deformity and the final esthetic sagittal positions of maxillary and chin in the present sample, and could be a useful tool for the planning of surgery-first approach in orthognathic surgery.

Objective: To evaluate the effect of bone defect regeneration and the periodontal status of the second molars after mandibular third molars extraction using β-tertiary calcium phosphate (β-TCP) in the test side compared with the spontaneously healed side. To the bone defect of mandibular second molars as a result of surgical removal of impacted mandibular third molars is a common phenomenon, many research shows that the mandibular second molars alveolar bone regeneration was about 1.5 mm and the periodontal pocket >7 mm was greater than 43.3% after mandibular third molars extraction. There has been significant progress researches in the repair of bone defect after the third molar removal, and bone graft filling was one of the effective methods. The bone graft substitutes include autogenous bone, allograft bone, xenograft bone and synthetic bone. Methods: A split mouth, randomized clinical study was designed. Fifteen patients with mandibular third molars in the same jaw planned to be extracted were enrolled in the study. One of the sockets of each patient was randomly selected and filled with easy-graft ^TMCLASSIC (test group). The contralateral socket was left to heal spontaneously (control group). cone beam computed tomography (CBCT) scans were performed the day after the extraction and after 6 months. The horizontal dimensional changes of the sockets were recorded. The newly formed bone volume in the bone was analyzed by CBCT, and the probing depth (PD) was recorded. Student’s t test was used to evaluate the difference between the two groups for each parameter, and the P value lower than 0.05 was considered to be statistically significant. Results: Fifteen patients (30 sockets) completed the flow-up, and all the 30 sockets healed uneventfully. After 6 months’ healing, the new bone volume fraction of the test group was 63.3%±2.2%, while the new bone volume fraction of the control group was 50.1%±1.9%. The vertical dimensional increment of the test group was (5.53±0.39) mm, while the vertical change of the control group was (1.53±0.27) mm. The distal buccal site PD of the second molar was (3.0±0.7) mm in the test group, and (6.5±0.8) mm in the control group. Statistically significant differences were detected between the two groups. Conclusion: The randomized controlled clinical trial showed that the application of β-TCP for bone defect repair after the mandibular third molars extraction resulted in more vertical bone regeneration and less probing depth when compared with what was spontaneously healed.

Objective: To compare the volume of autogenous bone particles harvested utilizing different techniques and various implant systems during implant surgery, and to determine the advantageous method to collect autogenous bone particles. Methods: Homogeneous epoxy resin simulated jaw bone model was enrolled. Bicon, Bego implant systems and Straumann tissue level implant systems were utilized. The two techniques were investigated. One method was low-speed drilling (50 r/min) without water irri-gating, and the other one was drilling with cold water irrigating to the ideal depth, then closing the water and drilling out with low speed (50 r/min). The bone particles in the drill groove and implant beds were collected. The volumes of the bone harvested were compared between the different techniques and also among the three implant systems, then they were compared with the volume of the bone harvested by the special bone drill. The sample size of each sub-group was 10. The bone particles were weighed by electronic balance after drying. Results: The harvested bone volume between the latch reamers and hand reamers of Bicon system with the first method was not significantly different. When the same size implant bed was prepared, the volume of the bone particles produced during the implant surgery with low-speed drill without water was significantly higher than that with the other method no matter Bicon [3.5 mm×10 mm hole for example (28.42±6.04) mg vs. (6.30±2.51) mg, P<0.001] or Bego system [2.8 mm×10 mm hole for example (28.95±5.39) mg vs. (4.61±3.39) mg, P<0.001] was used, and the ratio of bone volume between the first method and the second one was approximately 3.3 to 7.0 times. When using the second method to prepare the similar size implant bed, the bone volume was not significant different among Bicon, Bego and Straumann implant systems [Bicon (9.90±3.42) mg, Bego (8.70±4.09) mg, and Straumann (10.56±5.66) mg, P=0.69]. When preparing a 5mm-diameter-10mm-length hole with Bicon implant system and a 4.7mm-diameter-10mm-length with Bego implant system, the bone quantity harvested from each group was less than that harvested by special bone drill from Neo Biotech [Bicon (82.54±12.26) mg, Bego (85.07±12.64) mg vs. Neo Biotech (96.78±13.19) mg, P<0.05]. Conclusion: More autogenous bone can be harvested from implant beds by preparing with low-speed rolling without water than the method with water irrigation. When utilizing the same preparing method, the implant system has no impact on the volume of the bone harvested.

Objective: To study the visual sensitivity threshold of physician’s naked eye to the difference of nasolabial angle in edentulous jaw patients, and to provide a reference value for the study of aesthetic evaluation of soft tissue profile for the difference of nasolabial angle that can be recognized by human eyes. Methods: Three-dimensional facial images of three edentulous patients with different diagnostic dentures intro-oral were obtained.Lateral screenshots of each patient’s three-dimensional facial image with the same scale were obtained by using reverse engineering software (Geomagic studio 2014).The screenshot of the patient’s three-dimensional facial image with suitable lip support (The suitable lip support was confirmed by both patients and prosthodontists who had clinical experience for more than 20 years) was taken as the reference picture, and the remaining pictures were grouped with it respectively. All the pictures were observed in random order by the subjects. Fifteen dentists were asked to judge the difference of nasolabial angle between the two pictures of each group on the computer screen. The difference of nasolabial angle between the two pictures in each group was measured and calculated. The ROC curve was drawn, and the best cut-off value was calculated as the visual sensitivity threshold. Results: The data of the 15 subjects were used to draw ROC curves separately. The maximum and minimum best cut-off values were 5.55 degrees and 3.12 degrees respectively. The ROC curve of the whole 15 subjects was drawn after data aggregation, and the best cut-off value was 5.36 degrees (AUC=0.84>0.5, P=0.000<0.05).When the difference of nasolabial angle was above 5.36 degrees, the subjects could recognize it effectively. Conclusion: There is a visual limit in the observation of the nasolabial angle with the naked eye. In this study, a visual sensitivity threshold of 5.36 degrees for the difference of the nasolabial angle was obtained. The difference of nasolabial angle below this value can be regarded as no clinical significance. This result provides a reference value for human eyes to recognize the difference of nasolabial angle in soft tissue profile aesthetic evaluation. It can be applied to the aesthetic evaluation of soft tissue profile and can be used as the error level of related research with nasolabial angle as an index for accuracy evaluation.

Objective: To investigate the effect of preoperative condylar condition for mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis on the stability of the jaw after orthognathic surgery and on the postoperative condylar volume changes. Methods: In this retrospective study, from 2014 to 2019, 37 patients including 1 male and 36 female, aged between 21 to 34 years old with an average age of (28.03±6.52) years, were diagnosed with mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis by Peking University School and Hospital of Stomatology and received orthognathic surgery, meeting the inclusion criteria were included. According to the preoperative condylar condition. There were divided into smooth group and non-smooth group, the lateral cephalometric films 1 week (T0), 3 months (T1), 6 months (T2) and 1 year (T3) after surgery were used to establish the coordinate system and cephalometric analysis to determine the stability of the jaw after operation. The three-dimensional model of the condyle was segmented by cone beam computed tomography (CBCT) 1 week (T0), 3 months (T1), 6 months (T2) and 1 year (T3) after surgery and the volume was obtained to evaluate the change of the condyle volume after surgery. CBCT image data was used to evaluate the changes of the condylar condition after surgery, and to clarify the correlation between the postoperative condylar condition and jaw stability. SPSS 20.0 statistical software was used for statistical analysis, Fisher’s exact probability methods were used to compare whether there were statistically significant differences in the stability of the mandibular joint at stages T1, T2 and T3 with different preoperative condylar condition.Spearman correlation coefficient analysis and Mann-Whitney test were used to compare whether there were statistically significant differences in the volume changes at stages T1, T2 and T3 after surgery between the two groups. Results: The recurrence rates of the mandible in the condylar smooth group were T1 36.85%, T2 47.37% and T3 42.11%, respectively. The recurrence rates in the non-smooth condylar group were T1 27.78%, T2 44.44% and T3 55.56%, respectively. There was no statistical difference in the recurrence rates between the two groups at different time points. There was no significant difference in the condylar volume change between smooth group and non-smooth group. Conclusion: For patients with mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis and no significant changes in the condyle observed for one year before surgery, there is no difference in the influence of the preoperative condylar condition on the stability of jaw after operation, and no definite influence on the volume of the condyle after operation. Condylar resorption 3 months after surgery can cause instability of the jaw after orthognathic surgery.

Objective: To investigate the feasibility and accuracy of using digital technology to design anterolateral thigh flap (ALTF) in oral and maxillofacial defect reconstruction. Methods: Ten cases underwent oral and maxillofacial defects reconstruction with ALTFs in Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June 2019 to Oct. 2019 were enrolled. There were 7 males and 3 females with the mean age of 47.1 years. Preoperative high frequency color Doppler ultrasound examination was performed to detect the perforators of ALTF. CT data of the thigh was imported in DICOM (digital imaging and communications in medicine) format to the Proplan CMF 3.0 software (Materalise, Belgium), then virtual harvest of ALTF was performed according to the points of perforators detected by high frequency color Doppler ultrasound and the virtual flap volume was calculated by Proplan CMF 3.0 software. ALTF was harvested followed by preoperative virtual design, and the actual flap volume of ALTF was measured by the draining method during the surgery. Finally, the accuracy rate of using high frequency color Doppler ultrasound to detect perforators of ALTFs was calculated, and the differences between the virtual flap volume measured by Propaln CMF 3.0 software and the actual volume of ALTF by the draining method were compared using paired samples T test. Results: Fifteen perforators in the flaps area of 10 patients who underwent oral and maxillofacial defects reconstruction with ALTFs were detected by high frequency color Doppler ultrasound, and 16 perforators were identified during the surgery, with the accuracy rate of 87.5%. The flaps size ranged from 5 cm×7 cm to 8 cm×15 cm, all the 10 flaps survived. The donor sites were primarily closed without skin graft, and no surgery complication was found on the donor site. The mean flap volume measured by Propaln CMF 3.0 software was 71.4 cm ³ (range: 36.1-188.4 cm ³), and the mean volume measured by the draining method was 70.7 cm ³ (range: 38.3-172.5 cm ³). There was no significant difference between the virtual flap volume measured by Propaln CMF 3.0 software and the actual volume measured by draining method (t=0.318; P=0.758). Conclusion: Preoperative virtual design of ALTF has good feasibility and accuracy and can be used to guide the harvest of ALTF during operation.

Objective: To analyze the relationship between the width of the maxillary anterior teeth and the anterior arch perimeter, to analyze the change rule of the width of the anterior teeth and the anterior arch perimeter, when altered the convexity of the anterior arch, with the width of the maxillary anterior arch keeping constant, and to provide a reliable basis for later digitized and personalized aesthetic analysis of front teeth. Methods: In the study, 61 front teeth complete and well-arranged models had been selected from the working models after the prostheses in Department of Prosthodontics, Peking University School and Hospital of Stomatology, including 22 male models and 39 female models. A photograph was taken from the occlusal surface of each model using the fixed magnification with a single lens reflex camera. The width of anterior teeth, the width of anterior arch and the convexity of anterior arch had been measured using the Photoshop software. The ratio of the width of the anterior teeth to the width of the anterior arch was calculated. Keeping the width of anterior arch unchanged, the layer free transformation function used to add or decrease the curvature of the anterior arch from 1-5 mm, each circumfe-rence of the anterior arch was measured. According to the proportion of their anterior teeth in the anterior arch perimeter, the width of each anterior teeth crown under different convexities of anterior arch was calculated. SPSS 23.0 was used to analyze the ratio of the width anterior teeth to the anterior arch perimeter and correlation between the convexity of the anterior arch and the width of the anterior teeth. Results: The percentages of the median length of the anterior arch in the central incisor, lateral incisor and canine were 36.2%±1.3%, 30.2%±1.5%, and 33.6%±1.4%, respectively. The proportions were normal distributions and not related to the perimeter of the anterior arch. When the width of the anterior arch was constant, there was a positive correlation between the convexity of anterior arch in the range of 5 mm and the width of anterior teeth or the front arch circumference. With each increase or decrease of 1 mm of the convexity of anterior arch, the width of the middle incisor increased or decreased by about 0.18 mm, the half circumference of the anterior arch increased or decreased by about 0.50 mm. Conclusion: The width of the anterior teeth in the middle-distal direction remained stable in the anterior arch circumfe-rence. Within a certain range, when the width of the maxillary anterior arch remains unchanged, the width of the anterior teeth and the perimeter of the anterior teeth are positively correlated to the convexity of the anterior arch.

Objective: To provide a reference for using intraoral scanners for making clinical diagnostic dentures of edentulous jaws by comparing the accuracy of three intraoral scanners for primary impression and jaw relation record of edentulous jaws. Methods: This study contained 6 primary impressions of the edentulous patients. Each of the impressions consisted of the maxillary primary impression, the mandibular primary impression and the jaw relation record. For each of them, a dental cast scanner (Dentscan Y500) was used to obtain stereolithography(STL)data as reference scan, and then three intraoral scanners including i500, Trios 3 and CEREC Primescan were used for three times to obtain STL data as experiment groups. In Geomagic Studio 2013 software, trueness was obtained by comparing experiment groups with the reference scan, and the precision was obtained from intragroup comparisons. Registered maxillary data of the intraoral scan with reference scan, the morphological error of jaw relation record was obtained by comparing jaw relation record of the intraoral scan with the reference scan. Registered mandibular data with jaw relation record of intraoral scan and the displacement of the jaw position were evaluated. Independent samples t test and Mann-Whitney U test in the SPSS 20.0 statistical software were used to statistically analyze the trueness, precision and morphological error of jaw relation record of three intraoral scanners. The Bland-Altman diagram was used to evaluate the consistency of the jaw relationship measured by the three intraoral scanners. Results: The trueness of i500, Trios 3 and CEREC Primescan scanners was (182.34±101.21) μm, (145.21±71.73) μm, and (78.34±34.79) μm for maxilla; (106.42±21.63) μm, and 95.08 (63.08) μm, (78.45±42.77) μm for mandible. There was no significant difference in trueness of the three scanners when scanning the maxilla and mandible(P>0.05). The precision of the three scanners was 147.65 (156.30) μm, (147.54±83.33) μm, and 40.30 (32.80) μm for maxilla; (90.96±30.77) μm, (53.73±23.56) μm, and 37.60 (93.93) μm for mandible. The precision of CEREC Primescan scanner was significantly better than that of the other two scanners for maxilla(P<0.05). Trios 3 and CEREC Primescan scanners were significantly better than i500 scanner for mandible(P<0.05). The precision of the i500 and Trios 3 scanners for mandible was superior to maxilla(P<0.05). The upper limit of 95% confidence intervals of trueness and precision of three scanners for both maxilla and mandible were within ±300 μm which was clinically accepted. The morphological error of jaw relation record of the three scanners was (337.68±128.54) μm, (342.89±195.41) μm, and (168.62±88.35) μm. The 95% confidence intervals of i500 and Trios 3 scanners were over 300 μm. CEREC Primescan scanner was significantly superior to i500 scanner(P<0.05).The displacement of the jaw position of the three scanners was (0.83±0.56) mm, (0.80±0.45) mm, and (0.91±0.75) mm for vertical dimension; (0.79±0.58) mm, (0.62±0.18) mm, and (0.53±0.53) mm for anterior and posterior directions; (0.95±0.59) mm, (0.69±0.45) mm, and (0.60±0.22) mm for left and right directions. The displacement of the jaw position of the three scanners in vertical dimension, anterior and posterior directions and the left and right directions were within the 95% consistency limit. Conclusion: Three intraoral scanners showed good trueness and precision. The i500 and Trios 3 scanners had more errors in jaw relation record, but they were used as primary jaw relation record. It is suggested that three intraoral scanners can be used for obtaining digital data to make diagnostic dentures and individual trays, reducing possible deforming or crack when sending impressions from clinic to laboratory.

Objective: To evaluate the three-dimensional (3D) reconstruction accuracy of the intercuspal occlusion (ICO) of the dental casts, by the dental articulator position method, and provide a refe-rence for clinical application. Methods: The standard dental casts in ICO were mounted on average values articulator, and five pairs of milling resin cylinders were respectively attached to the base of both the casts. 100 μm articulating paper and occlusal record silicone rubber were used to detect the occlusal contact number between the posterior teeth of casts mounted on articulator in ICO. The occlusal contact numbers N_A detected by the two methods were calculated simultaneously, as the reference. After the upper and lower casts were scanned separately, and the buccal data of casts in ICO were scanned with the aid of the dental articulator position, registration was carried out utilizing the registration software. Then the digital casts mounted in ICO as well as the buccal occlusal data were saved in standard tessellation language (STL) format. Geomagic Studio 2013 software was used to analyze the contact number N_S between digital upper and lower casts by the “deviation analysis” function. The differences were compared between N_S and N_A, to evaluate the sensitivity and positive predict value (PPV) of the model scanner to reproduce the occlusal contact with the aid of dental articulator position. The distance D_R between the centers of the circles at the top surface of the upper and lower corresponding cylinders was obtained by the three-coordinate measuring system Faro Edge, as the reference value. The Geomagic Studio 2013 software was used to construct the cylinders of digital casts and the distance D_M between the centers of the circles at the top surface of the corresponding cylinders were measured, as the test value. The one-sample T test was used to analyze the variable differences between D_M and D_R. Results: The PPV of reproducing the occlusal contact point was 0.76 and sensitivity was 0.81. The distance error of the opposite cylinder was (0.232±0.089) mm. There was no statistical difference between the feature points 5-5’, while there were statistical differences between the other feature points. Conclusion: By the dental articulator position method, the model scanner reproduces the occlusal contact point with high sensitivity and PPV, and that meets clinical needs. Meanwhile, the distance between the feature points is greater than the reference value, which will lead to occlusal disturbance, and require clinical grinding.

Objective: To analyze the distribution and area of occlusal contacts of clinical dental model using three kinds of digital analysis methods, to compare the results of these methods and traditional occlusal analysis method, and to further analyze the characteristics of each digital analysis method. Methods: A set of plaster models of normal subjects was selected. The models were scanned by lab scanner 3shape E4 and the files were exported in a stereolithography file format. In 3D analysis software Geomagic Studio 2013 and Geomagic Qualify 2013, the corresponding results of 3D occlusal contact distribution and occlusal contact area were obtained through three digital analysis methods: “3D color difference map method”, “point cloud analysis method”, and “virtual articulating paper method”. The occlusal contact distribution and occlusal contact area were also obtained by two traditional occlusal analysis methods: “silicone interocclusal recording material method” and “scanned articulating paper mark method”. A threshold of 100 μm was used to analyze the occlusal contacts and 100 μm was also the thickness of arti-culating paper used in this study. The results of these five different occlusal analysis methods were evaluated qualitatively and quantitatively. Results: The results of 3D occlusal contact distribution obtained by the above five methods were basically consistent. The total occlusal contact area obtained by 3D color difference map method, point cloud analysis method, virtual articulating paper method, silicone interocclusal recording material method and scanned articulating paper mark method were 133.10 mm ², 142.08 mm ², 128.95 mm ², 163.31 mm ², and 100.55 mm ² respectively. There was little difference between the results of three digital analysis methods. The results of occlusal contact area obtained by the digital methods and the traditional methods were different. Conclusion: The three digital analysis methods can provide reliable and accurate analysis results of occlusal contact distribution and occlusal contact area of dental model. The results obtained by these methods can serve as references for the digital occlusal surface design of dental prosthesis and clinical occlusal analysis.

Objective: To evaluate the effects of cardiopulmonary fitness on arteriosclerotic cardiovascular disease (ASCVD) events in patients with different risks of ASCVD. Methods: This study enrolled 544 non ASCVD patients who underwent cardiopulmonary exercise testing in Peking University Third Hospital from September 2016 to April 2018. ASCVD overall risk assessment was conducted according to “Chinese Guidelines for the Prevention and Treatment of Adult Dyslipidemia”. Peak oxygen uptake (VO₂peak), the classic indicator of cardiopulmonary fitness, was accurately determined by cardiopulmonary exercise testing in all the patients. All of the patients were followed up clinically. Results: In the study, 506 patients completed the follow-up (250 low-risk patients, 93 moderate-risk patients and 163 high-risk patients). The median follow-up period was 19 months (9-28 months), and 51 patients developed ASCVD events during the follow-up period, of whom, 33 cases developed myocardial infarction, unstable angina or coronary revascularization, and 18 cases ischemic stroke, transient ischemic attack or carotid vascular revascularization. The patients were divided into the ASCVD group (n=51) and the non ASCVD group (n=455) based on the presence or absence of ASCVD events. VO₂peak [16.3(3.6) mL(kg·min) vs. 19.1(3.2) mL/(kg·min), P<0.001] in the ASCVD group were significantly lower than that in the non ASCVD group. Logistic regression analysis found VO2peak [OR 0.893 (95%CI:0.831-0.959), P=0.002] and ASCVD risk stratification [OR 1.428 (95%CI:1.028-1.878), P=0.031] were both independently associated with the occurrence of ASCVD events, which meant that every 1 mL/(kg·min) of increase in VO₂peak, the risk of ASCVD events was reduced by 11%. The patients were divided into low, moderate, and high VO₂peak according to the tertiles of their VO₂peak [14.4 mL/(kg·min), and 23.0 mL/(kg·min)]. Logistic regression analyses were performed using ASCVD events as a dependent variable in the patients with high-risk and low/moderate-risk of ASCVD respectively. In the patients with high-risk of ASCVD, the results suggested that the incidence of ASCVD events was significantly decreased in the patients with moderate VO₂ peak [OR 0.210 (95%CI:0.054-0.814), P=0.024] and high VO₂ peak [OR 0.146 (95%CI:0.025-0.870), P=0.035], but no significant effect of VO₂ peak elevation on the incidence of ASCVD events was found in the low/moderate-risk ASCVD patients. Conclusion: High cardiopulmonary fitness can significantly reduce the occurrence of ASCVD events in patients with high-risk of ASCVD.

Objective: To explore the prognosis factors that influence the postoperative survival rate in patients with malignant solitary pulmonary nodules and to provide a reference for the prognosis risk stratification of early lung cancer patients. Methods: In this study, we retrospectively reviewed 172 patients who were admitted to Peking University First Hospital from April 2006 to December 2013. All cases were radiologically defined as solitary pulmonary nodule and were pathologically confirmed to be stage Ⅰa non-small cell lung cancer after surgical procedure. The patients’ clinical and follow-up data were summarized and analyzed. The relevance between survival time and factors that may affect patients’ prognosis was evaluated, which included gender, age, clinical symptoms, smoking history, comorbidity index, tumor biomarkers, nodule type, type of surgery, nodule location, nodule histopathological type, nodule size, histopathological differentiation grade, proliferating cell nuclear antigen Ki-67 expression level and epidermal growth factor receptor (EGFR) gene mutation. Kaplan-Meier survival analysis, Cox univariant and multivariant regression analysis were conducted to evaluate the factors affecting prognosis. Results: The 3-year overall survival rate of the atients with malignant solitary pulmonary nodules was 93.6%, and the 5-year overall survival rate was 89.8%. Kaplan-Meier survival analysis and Cox univariant regression analysis showed that the overall survival rate of the male patients was significantly lower than that of the female patients. In addition, the elderly patients with histopathology characterized as high Ki-67 proliferation index were also associated with the worse overall survival (P<0.05). Cox multivariant regression analysis demonstrated that age more than 65 years as well as the high Ki-67 expression level were independent risk factors for overall survival in patients with malignant solitary pulmonary nodules (age: P=0.023, HR=3.531, 95%CI 1.190-10.472; Ki-67: P=0.004, HR=1.021, 95%CI 1.007-1.035). Conclusion: For patients with malignant solitary pulmonary nodules, with pathological defined as stage Ⅰa non-small cell lung cancer, age, gender and Ki-67 expression levels might be important prognostic factors. Comprehensive consideration of Ki-67 proliferation index and clinical pathological features may help to stratify the prognosis more accurately and guide the selection of appropriate therapeutic strategies, which needs to be verified by multi-center studies.

Objective:To investigate the types and distribution of musculoskeletal ultrasonographic changes of the symptomatic joints, their correlations with clinical manifestations in systemic lupus erythematosus (SLE) patients, as well as the differences of ultrasonographic changes from Rhupus syndrome [SLE overlapping with rheumatoid arthritis (RA)] patients. Methods: In the study, 114 SLE patients who complained of arthralgia or arthritis from May 2014 to August 2017 and 15 Rhupus syndrome patients were recruited for ultrasound evaluation. Ultrasound scans of the symptomatic joint areas were completed. The correlation between ultrasonographic changes and clinical characteristics was analyzed. Additionally, ultrasound changes of bilateral wrists and hands of the SLE patients were compared with those of the Rhupus syndrome patients. Results: In a total of the 114 SLE patients with 1 866 joints scanned, synovial hyperplasia, tenosynovitis, erosion, and osteophytes were all observed. Synovial hyperplasia was more often observed in wrists in 33.3% (23/69) patients, knees in 28.6% (12/42) patients, and ankles in 25.0% (7/28) patients. Tenosynovitis and erosion were most commonly found in shoulders in 35.0% (7/20) and 65.0% (13/20) patients. Osteophytes were more common in proximal interphalangeal (PIP) joints, elbows and knees. Among 69 patients with 22 joints (bilateral wrists and hands) scanned, 57 (82.6%) of them had ultrasonographic changes. Synovial hyperplasia was observed in 36.2% of the patients and erosion in 14.5% of the patients. The agreement between synovial hyperplasia and swollen joints in PIP was fair (κ=0.633, P<0.01), however poor in wrists between synovial hyperplasia and swollen/tender joints (κ=0.089, P=0.584). 18.4% patients with synovial hyperplasia had no tenderness or swollen clinically, while 15.8% patients with tenderness or swollen had no synovial hyperplasia on ultrasound. No correlation was found between ultrasonographic changes with the SLE disease activity index. Both synovial hyperplasia and erosion were more common in the Rhupus syndrome patients (73.3% vs. 36.2%, P=0.08; 66.7% vs. 14.5%, P=0.03) with significantly higher grey scale scores (7.4±6.4 vs. 1.6±4.1, P=0.04) than in the SLE patients. Conclusion: Variety of changes could be observed by ultrasound in different joint areas of SLE patients. The ultrasonographic changes and clinical manifestations did not always correspond to each other. Synovial hyperplasia and erosion was more common in Rhupus syndrome patients.

Objective: To investigate the outcomes of breast reconstruction with employing improved techniques throughout the tissue expander/implant two-stage breast reconstructed process, which involved the tissue expander placement, the saline filling intraoperatively and postoperatively, the implant selection, and the permanent implant replacement. Methods: In this study, 68 patients who had been provi-ded immediate or delayed tissue expander/implant two-stage breast reconstruction with autologous fat injection post-mastectomy in Peking University Third Hospital from April 2014 to September 2018 were involved, and the relevant information was analyzed retrospectively. The enhancements of the techniques, involving the incision selection, the expander placement, the principle of expansion, the management of capsule, the prosthesis selection, and the assisted reconstruction method were summarized, and the reconstruction outcomes were evaluated objectively through three-dimensional surface imaging. Results: Among the 68 patients in this study, immediate reconstruction was conducted in 25 patients and 43 patients underwent delayed reconstruction. The median time of tissue expansion was 7.0 (3.0, 20.0) months, and the average volume of expansion was (372.8±87.2) mL. The median size of breast implant was 215 (100, 395) mL. The median number of injections for fat grafting was 1 (1, 3), and the average volume of fat grafting was (119.3±34.1) mL. The median follow-up time was 7.0 (4.0, 24.0) months. During the process of breast reconstruction, the tissue expander leakage was observed in two patients, and one of them underwent expander replacement due to the secondary infection. In the immediate reconstruction cases, the volume symmetry of bilateral breasts after reconstruction got even better than that before mastectomy (t=4.465, P<0.01). And in the delayed reconstruction cases, the volume between bilateral breasts also achieved good symmetry after reconstruction (t=0.867, P>0.1). Conclusion: Good results of tissue expander/implant two-stage breast reconstruction could be achieved through the techniques enhancement, which involved the preferred transverse incision, the downward placement of expander, the rapid expansion of chest soft tissue, the release of capsule tension, the application of sizer in prosthesis selection, and the assisted autologous fat grafting.

Objective: To summarize the preliminary experience of hybrid operation for the treatment of symptomatic long-segment chronic internal carotid artery occlusion (CICAO) without stump. Methods: Clinical data of 12 patients of symptomatic long-segment CICAO without stump undergoing hybrid operation treatment from July 2015 to December 2017 were retrospectively analyzed. The safety and efficacy of hybrid operation for the treatment of symptomatic long-segment CICAO without stump were preliminarily assessed. CICAO was defined as occlusion time being more than 4 weeks. The primary outcome was defined as any stroke (including ischemic or hemorrhagic) or deaths from any cause after hybrid operation within 30 days. The secondary outcome was defined as successful revascularization and occurrence of >50% in-stent restenosis during the follow-up period. Results: In this group, the symptomatic long-segment CICAO of 11 patients were successfully recanalized. Technical success rate was 91.7% (11/12). The main complication rate was 8.3% (1/12). This patient encountered iatrogenic internal carotid artery cavernous sinus fistula caused by micro-guide wire in the midway of the hybrid operation, the pro-ximal segment of this internal carotid artery was ligated and the iatrogenic internal carotid artery cavernous sinus fistula disappeared in the following digital subtraction angiography image. No patient encountered hemorrhagic stroke and ischemic stroke. No death complications occurred. In this group 10 patients of them were followed up. The follow-up period ranged from 10 to 32 months [mean, (19±9) months]. During the follow-up period, 1 patients developed in-stent restenosis and improved after reoperation of percutaneous transluminal angioplasty by the right size balloon without stenting treatment. Conclusion: Hybrid operation for the treatment of highly screened patients with symptomatic long-segment CICAO without stump is safe and effective, could reduce the incidence of complications and improve procedural success rate.

Objective: To analyze the clinical data of patients undergoing intravenous sedation in oral and maxillofacial surgery, to understand the epidemiological characteristics, to evaluate the efficacy and safety of intravenous sedation for oral surgery, and to summarize our experience. Methods: We retrospectively reviewed the clinical data of patients undergoing intravenous sedation between January 2010 and December 2018 in the Department of Oral and Maxillofacial Surgery, Peking University School of Stomatology. The gender, age, source, disease types, the values of perioperative vital signs, the use of sedatives and analgesics, duration of surgery and sedation, effect of sedation during the operation and the postoperative anterograde amnesia were analyzed. Results: A total of 2 582 patients experienced oral surgery by intravenous sedation. The peak age was 3.5 to 10 years and between 21 to 40 years. Supernumerary teeth (38%, 981/2 582) and impacted third molars (30%, 775/2 582) were the major disease types, and other types of disease accounted for 32 percent (826/2 582). The values of heart rate(HR),mean arterial pressure(MAP),respiration rate(RR) and bispectral index(BIS) showed statistically significant differences at the time of before sedation, local anesthesia injection, surgical incision, 10 min after operation and the end of operation. In the study, 69%(1 781/2 582) cases received midazolam alone, 7%(181/2 582) cases received propofol alone, and 24%(620/2 582) cases received midazolam and propofol combined for intravenous sedation. Fentanyl (33%, 852/2 582)was the most common intravenous analgesic we used, followed by flurbiprofen axetil (23%, 594/2 582) and ketorolac tromethamine (6%, 157/2 582). Besides, 35% (907/2 582)patients didn't use any intravenous analgesic during the surgery. The average operation time was (31.2±20.8) min, and the average sedation time was (38.4±19.2) min. During the surgery procedure, most of the patients scored on a scale of 2 to 4 according to the Ramsay sedation score (RSS). The postoperative anterograde amnesia rates of local anesthesia injection, surgical incision and dental drill during surgery were 94% (2 431/2 582), 92% (2 375/2 582) and 75% (1 452/1 936). Conclusion: Intravenous sedation on the oral and maxillofacial surgery is effective and safe, can make the patients more comfortable, and should be further promoted and applied.

Objective: To explore the possibility of the Smile Lite MDP (Smile Lite Mobile Dental Photograph) portable dental photography system applying in anterior teeth aesthetic photography, and to provide the chance to simplify aesthetic photography process and facilitate communication among patients, dentists and dental technitians. Methods: The Smile Lite MDP photography system combined with the smartphone were used to photograph the front occlusal phase photos of anterior teeth. The photographic conditions including the color temperature parameter, the Smile Lite MDP light position and the intensity settings were explored. The best photographic conditions were chosen by blind evaluation within expe-rienced dentists and technicians through the method of the visual analogue scale/score (VAS) evaluation, which went through statistical analysis to figure out the optimum photograghic conditions. Smile Lite MDP photography system was used to photograph the front occlusal phase photos of anterior teeth under the optimum parameter by different magnifications. The width/height ratio of the central incisor and the front width ratio of the upper anterior teeth in those photos were measured and calculated respectively. The accuracy of the anterior teeth photos taken by Smile Lite MDP photography system was analyzed based on the photographs taken by digital single lens reflex (DSLR) camera. Results: The optimum color temperature parameter of Smile Lite MDP portable camera system was 5 000 K, the optimum magnification was 4 times, the best light position was the side lights of Smile Lite MDP, the optimum intensity of lights was 2 grades. Photos taken by the optimum parameters won the highest score during the VAS evaluation and the result of statistical analysis had significant difference compared with other groups (P<0.05). When comparing the photos of the upper anterior teeth taken by the Smile Lite MDP portable photography system using 4 times magnification or by DSLR using the standard parameters, there was no significant difference neither in the width/hieght ratio of the central incisor nor in the front width ratio of the upper anterior teeth (P>0.05). Conclusion: The Smile Lite MDP portable dental photography system applying in anterior teeth aesthetic analysis photography was capable to show the color and shape of anterior teeth in an accurate way by using the right photography parameters. Therefore, Smile Lite MDP portable dental photography system was considered to be a simple and easy photographic tool in clinical work.

Plunging ranula is rare and manifests as the submandibular or submental cystic mass, without intra-oral abnormality. It usually causes misdiagnosis and malpractice. This article reported a case of plunging ranula that appeared as a massive mass located behind the left ear. A 6-year-old child presented with recurrent left retroauricular swelling over six months without obvious inducement. The mass showed repeatedly swelling and persistent skin ulcers. Physical examinations described a fluctuant, nontender mass behind the left ear whose size was about 5 cm×5 cm×3 cm. The skin upon the surface of the mass was thin and red, and overflowed yellow slime-like contents. Computed tomography (CT) showed an extensive cystic lesion in the left neck. After local incision and drainage the mass was shrink. With the primary clinical diagnosis of branchial cyst, the patient underwent mass resection through postauricular incision. During the operation, the fistula was traced to the area around the sublingual gland, and the postoperative pathology report demonstrated cystic spaces occurring in soft tissue without lymphoid tissue. One month postoperatively, the patient presented the “egg-white”, wire-drawing transparent viscous fluid outflowing from the left external auditory canal, indicating that the fluid in the external auditory canal originated from the sublingual gland and the disease was the plunging ranula presenting as a giant left retroauricular mass. We readmitted the patient to the hospital and the ipsilateral sublingual gland was completely removed in the mouth under general anesthesia. No clinical evidence of recurrence was found at the end of 9 months follow-up. So far, there is no literature reporting plunging ranula behind ear. This case report describes the clinical manifestation, diagnosis, and differential diagnosis and treatment of a case of plunging ranula, and reveals that, other than the submandibular or submental, plunging ranula also could be found in retroauricular region. The plunging ranula is difficult to fully confirm through a clinical character, and usually easy to be misdiagnosed as other tumors, like lymphatic malformation, venous malformations, etc. Radiographic examination and/or puncture fluid observation are required for identification. “Egg-white”, wire-drawing mucous secretion is the most important characteristic in clinical diagnosis of sublingual gland cyst. However, if sublingual gland resection, i.e. removal of the source of cyst fluid is performed, a good prognosis can be achieved.