In fixed prosthodontics, clear exposure of the preparation margin is the prerequisite for obtaining accurate digital impressions and improving the marginal fit of restorations. To resolve the issues associated with the cord retraction technique, such as pain, acute injury, and prolonged procedural time, this study proposes a new technology for intraoral digital impression taking with pneumatic gingival retraction. The new scanning head blows a high-speed airflow that instantaneously separates the free gingiva, locally exposing the subgingival preparation margin. Combined with the farthest point preservation stitching algorithm based on the distance from the normal vector and high-speed laser scanning photography, it achieves global preparation edge data and gingival reconstruction, realizing painless, non-invasive, and efficient precise acquisition of the preparation margin. Using this new technique, a patient with a full porcelain crown restoration on a posterior tooth was treated. The digital impression revealed a clear margin of the preparation, and the crown made from this data has a good marginal fit.

Purpose/Significance To reveal secondary infection knowledge related to infectious diseases by mining public literature data,and to promote the research and construction of the secondary infection monitoring platform,so as to improve the prevention and control level of infectious diseases in China.Method/Process The literature based discovery method is firstly adopted to mine and ana-lyze the secondary diseases from large-scale biomedical literature data,taking viral hepatitis,human immunodeficiency virus(HIV)infection and tuberculosis infection as the examples.Result/Conclusion 3 kinds of secondary diseases including infectious diseases,non-infectious diseases and even tumors,are found from more than 36.8 million PubMed literature.The research results not only validate that this method provides a new approach for systematically and comprehensively reveal secondary infection knowledge related to infectious diseases,but also provide more powerful literature evidences for effective monitoring and early intervention of secondary diseases.

Objective A simulation study was conducted to explore the effect and performance of g-computation-based joint mixed-effects model(JMM)on causal inference for controlling unmeasured confounders in longitudinal studies.Methods Longitudinal data including baseline and two follow-up visits were generated by computer simulations.The simulation scenarios included different sample sizes,the presence or absence of unmeasured confounders,and effects of unmeasured confounders.Causal effects were estimated using g-computation-based JMM,linear mixed-effects model,fixed effects model,and longitudinal target maximum likelihood estimation,respectively.Indicators including mean absolute deviation(MAD),standard error,root mean square error(RMSE),and 95%confidence interval coverage(95%CI coverage)were used to evaluate and compare the causal inference performance.Based on the physical examination cohort data of the menopausal women,four models were used to estimate the causal association between serum follicle-stimulating hormone(FSH)levels and lumbar bone density in menopausal women respectively,verifying the causal inference performance of models in the real longitudinal data.Results JMM had a better accuracy of causal inference with controlling unmeasured confounders.But its estimation stability was slightly worse.When strong unmeasured confounders existed,only JMM can accurately estimate the causal effect,and its precision and authenticity were better in scenarios with large sample sizes.Conclusion JMM can effectively control the unmeasured confounders and perform approximately unbiased causal estimation in longitudinal studies.

Objective:To evaluate the effect of ultrasound-guided adductor canal block with bupivacaine liposome on analgesia in elderly patients undergoing total knee arthroplasty.Methods:This was a prospective study. Sixty American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ patients, regardless of gender, aged 65-83 yr, weighing 50-80 kg, scheduled for elective unilateral total knee arthroplasty under subarachnoid anesthesia from April 2023 to January 2024 in Zhengzhou Orthopaedic Hospital, were divided into 2 groups ( n=30 each) using a random number table method: bupivacaine liposome group (LB group) and ropivacaine group (R group). Ultrasound-guided adductor canal block was performed at 30 min before subarachnoid anesthesia, bupivacaine liposome diluent 20 ml (133 mg) was injected in LB group, and 0.5% ropivacaine 20 ml was injected in R group. Patient-controlled intravenous analgesia was performed after operation, and tramadol was used for rescue analgesia when the visual analogue scale (VAS) score ≥3. VAS scores at rest and during activity were recorded at 8, 12, 24, 48 and 72 h after surgery. The time to the first pressing analgesia pump and rescue analgesia were recorded within 72 h after surgery. The quadriceps muscle strength was measured at 1 day before surgery and 12, 24, 48 and 72 h after surgery. The knee joint range of motion was assessed at 1 day before surgery and 24, 48 and 72 h after surgery. Patient′s satisfaction with analgesia was recorded at 72 h after surgery. The adverse reactions within 72 h after surgery were also recorded. Results:Compared with R group, VAS scores at rest and during activity were significantly decreased at 12, 24, 48 and 72 h after surgery, the time to the first pressing analgesia pump was prolonged, the rate of rescue analgesia after surgery was decreased, the score for the patient′s satisfaction with analgesia was increased, the knee joint range of motion was increased ( P<0.05), and no significant change was found in the quadriceps muscle strength and incidence of adverse reactions in LB group ( P>0.05). Conclusions:Ultrasound-guided adductor canal block with bupivacaine liposome provides better analgesia than ropivacaine in elderly patients undergoing total knee arthroplasty.

Objective:To summarize the prenatal ultrasound features of fetal cleidocranial dysplasia (CCD) and provide references for clinical consultation.Methods:A retrospective analysis was conducted on the prenatal ultrasound features, genetic testing results, and prognosis of a CCD fetus diagnosed at Qingdao Women and Children's Hospital in June 2023. Relevant literature on CCD was retrieved from the CNKI, Yiigle, Wanfang, and PubMed databases including cases confirmed by genetic testing or postnatal clinical phenotype and imaging with relatively complete prenatal ultrasound information. The prenatal ultrasound features of CCD fetuses were summarized using descriptive statistical analysis.Results:(1) In this case, prenatal ultrasound at 25 weeks of gestation indicated widened cranial sutures with clear near-field intracranial structures, absence of the nasal bone, shortened and rigid bilateral clavicles, and mildly shortened bilateral femurs and humeri. Chromosomal karyotyping and chromosomal microarray analysis showed no abnormalities, but whole exome sequencing detected a RUNX2 gene mutation, leading to a diagnosis of CCD combined with the ultrasound phenotype. At 36 weeks of gestation, the mother experienced premature rupture of membranes and delivered a male infant vaginally. Bedside X-rays indicated bilateral wet lungs and bilateral clavicular dysplasia in the newborn. Telephone follow-up at 9 months showed no abnormalities in growth and development. (2) Literature review: Thirteen cases from 13 articles were included, along with this case, totaling 14 CCD fetuses. The main ultrasound phenotypes of CCD fetuses were clavicular dysplasia (12/14), incomplete cranial ossification (10/14), absence of the nasal bone (8/14), and shortening of the femur (12/14). Other ultrasound phenotypes included scapular dysplasia, short ribs, and increased interocular distance. Conclusion:Clavicular dysplasia and incomplete cranial ossification are the most specific signs of fetal CCD, while absence of the nasal bone and mild femoral shortening are secondary features of CCD.

Objective To observe the protective effect of 2% taurine on corneal endothelial cells injured by benzalkonium chloride in rats. Methods Six piece of corneal endodermis and elastic layer tissue slices were prepared from 6 eyes of 3 SPF SD rats and randomly divided into three groups. The corneal endothelial cells of rats were cultured by tissue block culture for 1 day, then the control group cells were added with 2% taurine solution, while the experimental group cells were added with 2% taurine solution and 0.01% or 0.03% benzalkonium chloride solution. After 1, 2, 4, 5, 6 and 8 days of continuous culture, the growth of corneal endothelial cells in each group was observed under an inverted microscope, and the morphology of endothelial cells was observed under an optical microscope after Wright staining. Results Treated with 0.01% benzalkonium chloride and 2% taurine for 1 day, polygonal endothelial cells appeared on the edge of corneal tissue mass, and the cells were transparent. After 2 days, the number of polygonal cells increased, and there was no fusion growth between cells. After 3 days, the number of polygonal cells decreased and no mitotic signs were observed in endothelial cells. After 4 days, the endothelial nuclei were deeply stained and polygonal cells were rare. After 5 days, the number of endothelial cells decreased, and cell body shrinkage and death occurred. In the experimental group treated with 0.03% benzalammonium chloride and 2% taurine for 1 day, no endothelial cell growth was observed and the cells were sparsely-scattered. In control group, polygonal endothelial cells and a few endothelium-like polygon cells appeared at the edge of tissue blocks after 1 day. After 3 days, the number of polygonal cells at the edge of tissue blocks increased, and there was a phenomenon of gradual fusion growth. After 5 days, the number of endothelial cells increased, and the cells were mostly hexagonal. After 8 days, the endothelial cells formed large sheets, the cell bodies were hexagonal or round, and the nuclei were divided. The growth of corneal endothelial cells in the left and right eyes was uniform, and there was no significant difference in the morphology of the left and right eye endothelial cells in the 0.01% and 0.03% benzalammonium chloride treatment groups and the control group. Conclusion 2% taurine had no protective effect on corneal endothelial cells injured by benzalammonium chloride.

Objective:To investigate the incidence and treatment of gastric cancer in 16 medical centers in Tianjin from 2020 to 2021.Methods:The retrospective and descriptive study was conducted. The clinical data of 3 122 gastric cancer patients who underwent surgery in 16 medical centers, including Tianjin Medical University Cancer Institute & Hospital, et al, in Tianjin from 2020 to 2021 were collected. There were 2 112 males and 1 010 females, aged (64±11)years. Observation indicators: (1) general data of patients; (2) treatment situations; (3) postoperative complications. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were descri-bed as absolute numbers or percentages, and comparison between groups was conducted by the chi-square test. Results:(1) General data of patients. From 2020 to 2021, a total of 3 122 gastric cancer patients received surgeries in 16 medical centers in Tianjin, including 2 112 males and 1 010 females. There were 1 443 cases in 2020, including 976 males and 467 females, aged (63±11) years. There were 1 679 cases in 2021, including 1 136 males and 543 females, aged (65±11) years. Of the 3 122 pati-ents, cases in stage Ⅰ, Ⅱ, Ⅲ, Ⅳ were 696, 667, 1 466, 293, accounting for 22.293%(696/3 122), 21.365%(667/3 122), 46.957%(1 466/3 122), 9.385%(293/3 122), respectively. Cases with early gastric cancer, locally advanced gastric cancer, advanced gastric cancer account for 17.265%(539/3 122), 73.350%(2 290/3 122), 9.385%(293/3 122). There were 2 829 patients without distant metastasis and 293 patients with distant metastasis. For the 2 829 patients without distant metas-tasis, cases in stage T1, T2, T3, T4a, T4b accounted for 19.053%(539/2 829), 12.089%(342/2 829), 20.148%(570/2 829), 41.499%(1 174/2 829), 7.211%(204/2 829)respectively, cases in stage N0, N1, N2, N3 account for 37.328%(1 056/2 829), 16.331%(462/2 829), 15.836%(448/2 829), 30.505%(863/2 829). For the 293 advanced gastric cancer patients with distant metastasis, 190 cases had peri-toneal metastasis, 47 cases had lymph node metastasis, 27 cases had ovarian metastasis, 37 cases had liver metastasis, 14 cases had other metastasis (some patients had ≥2 distant metastases). (2) Treatment situations. ① For the 539 with early gastric cancer, cases undergoing endoscopic submu-cosal dissection, laparoscopic surgery, open surgery were 22, 150, 86 in 2020, versus 19, 212, 50 in 2021, showing a significant difference between them ( χ2=19.42, P<0.05). For the 498 patients with early gastric cancer who underwent laparoscopic or open surgery, cases undergoing open surgery including total gastrectomy, distal gastrectomy, proximal gastrectomy were 25, 81, 30, and cases undergoing laparoscopic surgery including total gastrectomy, distal gastrectomy, proximal gastrec-tomy were 18, 309, 35, respectively, showing a significant difference between them ( χ2=40.62, P<0.05). For the 2 290 patients with locally advanced gastric cancer, cases undergoing open surgery and laparoscopic surgery were 446 and 617 in 2020, versus 410 and 817 in 2021, showing a significant difference between them ( χ2=17.75, P<0.05). For the 2 290 patients with locally advanced gastric cancer, cases undergoing open surgery including total gastrectomy, distal gastrectomy, proxi-mal gastrectomy were 336, 377, 143, and cases undergoing laparoscopic surgery including total gastrectomy, distal gastrectomy, proximal gastrectomy were 377, 920, 137, respectively, showing a significant difference between them ( χ2=89.64, P<0.05). Of the 293 patients with advanced gastric cancer, 175 cases underwent surgeries due to hemorrhage, stenosis, perforation, 76 cases under-went surgery after chemotherapy, 42 cases underwent surgery directly. ② For 756 cases of 3 122 pati-ents undergoing total gastrectomy, 357 and 4 cases received open digestive tract reconstruction including Roux-en-Y and other anastomosis, versus 380 and 15 cases with laparoscopic digestive tract reconstruction including Roux-en-Y and other anastomosis, showing a significant difference between them ( χ2=5.57, P<0.05). For 1 687 cases undergoing distal gastrectomy, 84, 160, 158, 55 cases received open digestive tract reconstruction including Billroth Ⅰ anastomosis, Billroth Ⅱ + Braun anastomosis, Roux-en-Y anastomosis, uncut Roux-en-Y anastomosis, versus 154, 489, 417, 170 cases with laparoscopic digestive tract reconstruction including Billroth Ⅰ anastomosis, Billroth Ⅱ + Braun anastomosis, Roux-en-Y anastomosis, uncut Roux-en-Y anastomosis, showing a significant difference between them ( χ2=10.90, P<0.05) . Of the 539 patients with early gastric cancer, 65 cases had lymph node metastasis, in which 18 of 306 stage T1a cases had lymph node metastasis and 47 of 233 stage T1b cases had lymph node metastasis. The number of detected lymph nodes for the 2 290 patients with advanced gastric cancer was 31±15, including ≥16 for 2 059 cases and ≥30 for 1 276 cases. Of the 3 122 patients, cases with neoadjuvant therapy, complete response and incomplete response was 128, 13 and 115 in 2020, versus 250, 49 and 201 in 2021, showing a significant difference between them ( χ2=5.51, P<0.05). (3) Postoperative complications. Of the 3 122 patients, 746 cases had postoperative complications, with an incidence of 23.895%(746/3 122). There were 62 patients with grade 3 or more complications. Reoperation was conducted in 34 patients. There were 14 cases of postoperative death. The duration of postoperative hospital stay and hospital expense were (11±5)days and (98 114±46 598)yuan for the 3 122 patients, (26±14)days and (122 066±68 317)yuan for cases with complications, (40±21)days and (196 926±12 747)yuan for cases with grade 3 or more complications. Conclusion:Compared with 2020, cases undergoing laparoscopic surgery and distal gastrectomy for gastric cancer in Tianjin increases in 2021, and the digestive tract reconstruction also differs. The number of patients with neoadjuvant chemotherapy and complete response rate for advanced gastric cancer increases.

OBJECTIVE: To measure the concentration of bone morphogenetic protein 2 (BMP-2) in demineralized bone matrix (DBM) prepared from different long bones and to evaluate the osteoinductivity of different DBM on MC3T3-E1 cells. METHODS: Different bones from the same cadaver donor were used as the initial materials for making DBM, which were divided into ulna group (uDBM), humerus group (hDBM), tibia group (tDBM), and femur group (fDBM) according to the origins, and boiled DBM (cDBM) was taken as the control group. The proteins of DBM were extracted by guanidine hydrochloride, and the concentrations of BMP-2 were determined by ELISA assay. Then the DBM were co-cultured with MC3T3-E1 cells, the proliferation of MC3T3-E1 cells was observed by cell counting kit 8 (CCK-8) assay. The osteogenic differentiation ability of MC3T3-E1 cells was qualitatively observed by alizarin red, alkaline phosphatase (ALP), and Van Gieson staining, and the osteogenic differentiation ability of MC3T3-E1 cells was quantitatively analyzed by ALP content. Linear regression was used to analyze the effect of BMP-2 concentration in DBM on ALP synthesis. RESULTS: There were significant differences in the concentration of BMP-2 among the DBM groups (P<0.05). The concentrations of BMP-2 in the lower limb long bone were higher than those in the upper limb long bone, and the concentration of BMP-2 in the fDBM group was about 35.5 times that in the uDBM group. CCK-8 assay showed that the cells in each group continued to proliferate within 5 days of co-culture, and the absorbance (A) values at different time points were in the order of cDBM groupP<0.05). Linear regression analysis showed that y^=0.361+0.017x, the effect of BMP-2 concentration in DBM on cellular ALP content was significant (t=3.552, P=0.005); for every 1 ng/g increase in BMP-2 concentration, ALP content would increase by 0.017 [95%CI (0.006, 0.027)] U/100 mL. CONCLUSION The concentration of natural BMP-2 in different long bones varies greatly, and the lower limb long bone is higher than the upper limb long bone. The harvested location of bone material was an important factor affecting the osteoinductivity of DBM.
Alkaline Phosphatase ; Bone Matrix ; Bone Morphogenetic Protein 2 ; Cell Count ; Coloring Agents ; Osteogenesis ; Animals ; Mice

OBJECTIVE: To study the effectiveness of TightRope elastic fixation combined with functional total repair of the inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury. METHODS: The clinical data of 34 patients with distal tibiofibular syndesmosis injury who met the selection criteria between January 2020 and January 2022 were retrospectively analyzed, and they were divided into improved group (TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament) and control group (distal tibiofibular screw fixation) according to the surgical methods, with 17 cases in each group. There was no significant difference in age, gender, body mass index, fracture type, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications were recorded in the two groups. The American Orthopaedic Foot and Ankle Society (AOFAS) score, ankle metatarsal flexion and dorsal extension range of motion were used to evaluate the ankle function. The patient satisfaction survey was conducted at last follow-up. RESULTS: All 34 patients were followed up 8-20 months, with a median of 13 months. The operation time and intraoperative blood loss in the improved group were significantly longer than that in the control group (P<0.05). In the improved group, no infection or poor reduction occurred, and only 1 patient had TightRope knot reaction at 6 months after operation. In the control group, there were 2 cases of poor reduction, 1 case of lower tibiofibular screw rupture, and 1 case of subcutaneous infection (cured after anti-infection treatment). There was no significant difference in the incidence of complications between the two groups (P>0.05). At last follow-up, the AOFAS score and ankle metatarsal flexion and dorsal extension range of motion of the improved group were significantly better than those of the control group (P<0.05). The satisfaction rates of patients in the improved group and the control group were 94.1% and 82.4%, respectively, showing significant difference (P<0.05). CONCLUSION TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury has sufficient fixation strength, and can achieve better effectiveness and joint function compared with traditional screw fixation.
Humans ; Ankle Joint/surgery* ; Blood Loss, Surgical ; Ligaments/surgery* ; Plastic Surgery Procedures ; Retrospective Studies ; Ankle Injuries/surgery*

OBJECTIVE: To compare the effectiveness of subtalar arthroereisis (STA) combined with modified Kidner procedure versus STA alone in the treatment of flexible flatfoot combined with painful accessory navicular bone in children. METHODS: The clinical data of 33 children with flexible flatfoot combined with painful accessory navicular bone who were admitted between August 2018 and August 2021 and met the selection criteria were retrospectively analyzed. They were divided into a combination group (17 cases, treated by STA combined with modified Kidner procedure) and a control group (16 cases, treated by STA alone) according to the surgical methods. There was no significant difference in baseline data between the two groups ( P>0.05), such as gender, age, affected side of the foot, disease duration, and preoperative visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, talus-first metatarsal angle (T1MT), talus-second metatarsal angle (T2MT), talonavicular coverage angle (TCA), talus first plantar angle (Meary angle), calcaneal inclination angle (Pitch angle), and heel valgus angle (HV). The operation time, incision length, intraoperative blood loss, number of intraoperative fluoroscopies, and perioperative complications were recorded in both groups. The anteroposterior, lateral, and calcaneal axial X-ray films for the affected feet were taken regularly, and T1MT, T2MT, TCA, Meary angle, Pitch angle, and HV were measured. The VAS score, AOFAS ankle-hindfoot score were used to evaluate pain and functional recovery before and after operation. RESULTS: Surgeries in both groups were successfully performed without surgical complication such as vascular, nerve, or tendon injuries. Less operation time, shorter incision length, less intraoperative blood loss, and fewer intraoperative fluoroscopies were found in the control group than in the combination group ( P<0.05). One case in the combination group had partial necrosis of the skin at the edge of the incision, which healed after the dressing change and infrared light therapy, and the rest of the incisions healed by first intention. All children were followed up 12-36 months, with a mean of 19.6 months. At last follow-up, VAS score and AOFAS ankle-hindfoot score significantly improved in both groups when compared with preoperative ones ( P<0.05), and the differences of these scores between before and after operation improved more significantly in the combination group than in the control group ( P<0.05). Imaging results showed that the T1MT, T2MT, TCA, Meary angle, and HV significantly improved in both groups at last follow-up when compared with preoperative ones ( P<0.05), and the Pitch angle had no significant difference when compared with preoperative one ( P>0.05). But there was no significant difference in the difference of these indicators between before and after operation between the two groups ( P>0.05). CONCLUSION Both procedures are effective in the treatment of flexible flatfoot children with painful accessory navicular bone. STA has the advantage of minimally invasive, while STA combined with modified Kidner procedure has better effectiveness.
Humans ; Child ; Flatfoot/surgery* ; Blood Loss, Surgical ; Retrospective Studies ; Treatment Outcome ; Osteotomy/methods* ; Talus ; Pain