Radiographic and clinical outcomes of muenster and sugar tong splints for distal radius fractures: a comparative study.

BACKGROUND: Non-operative management is typically indicated for extra-articular distal radius fractures. Conservative treatments such as Sugar tong splints (STs) and Muenster splints (MUs) are commonly used. However, there is limited research and outcome data comparing the two splint types. Therefore, this study aimed to investigate and compare the radiographic and clinical outcomes of treatment using STs and MUs. METHODS: In this retrospective comparative study, we aimed to evaluate and compare the radiographic and clinical outcomes of STs and MUs for the treatment of distal radius fractures. The study included 64 patients who underwent closed reduction (CR) in the emergency room and were treated with either STs or MUs splints (STs group: n = 38, MUs group: n = 26). Initial X-rays, post-CR X-rays, and last outpatient follow-up X-rays were evaluated. Radial height (RH), ulnar variance (UV), radial inclination (RI), and volar tilt (VT) were measured by a blinded investigator. The Quick DASH form was applied to measure patients' satisfaction after treatments. RESULTS: There were no significant differences in baseline characteristics, initial radiographic measurements, or radiographic measurements immediately after CR between the two groups. However, the overall radiological values deteriorated to some degree in both groups compared to the post-CR images. Furthermore, using a paired test, the STs group showed significant differences in RH and RI, and the MUs group showed significant differences in RH and UV between the last follow-up and post-CR images. CONCLUSIONS: The study concluded that there was no difference in clinical outcomes between the two splint types. However, both STs and MUs groups showed reduced radiographic parameters, and the MUs group showed a significant reduction of RH and UV in the treatment of distal radius fractures. LEVEL OF EVIDENCE: Level IV; Retrospective Comparison; Treatment Study.

Accuracy of zirconia crown manufactured using stereolithography and digital light processing.

OBJECTIVES: The aim of this study is to evaluate the accuracy of zirconia crowns fabricated using stereolithography (SLA) and digital light processing (DLP) and to compare their accuracy with those fabricated using the subtractive manufacturing (SM) method. METHODS: A typodont model with a prepared maxillary first molar was scanned, and the anatomical contour crown was designed using dental computer-aided-design (CAD) software. The designed file in standard tessellation language (STL) format was used to fabricate 10 crowns per group. The crowns were manufactured using a dental milling machine (Datron D5; MLC group), SLA (CERAMAKER 900; SLAC group), and DLP (ZIPRO; DLPC group) printers. The fabricated crowns were scanned using a dental laboratory scanner and saved in three parts: the external, intaglio, and marginal surfaces. For accuracy assessment, these parts were superimposed to the reference file. Root mean square (RMS) values were evaluated using three-dimensional analysis software (Geomagic Control X). Statistical significance was evaluated using a nonparametric Kruskal-Wallis test (α = 0.05) and a post-hoc Mann-Whitney U test with Bonferroni correction (α = 0.016). RESULTS: Trueness evaluation revealed the lowest RMS value in all areas in the MLC group, followed by that in the DLPC group. The precision evaluation revealed the lowest RMS value in all areas in the MLC group. Statistically significant differences were observed among the groups in the external, intaglio, and marginal surface (P < 0.05). CONCLUSIONS: Although the restorations fabricated using SM revealed higher accuracy, the crowns manufactured using SLA and DLP methods were considered clinically acceptable. CLINICAL SIGNIFICANCE: In the production of zirconia crowns, subtractive manufacturing continues to demonstrate significantly higher accuracy compared to additive manufacturing. However, crowns fabricated using the additive manufacturing method also demonstrated high accuracy.

Intraoperative assessment of hindfoot alignment using C-arm fluoroscopy.

BACKGROUND: Hindfoot malalignment can cause various foot and ankle problems. For better surgical performance and correction of hindfoot malalignments, reliable intraoperative determination of hindfoot alignment is essential. However, there is no standard method for the intraoperative assessment of hindfoot alignment. We devised an intraoperative modified Méary posteroanterior (IOPPA) view to assess intraoperative hindfoot alignment. This study aimed to compare this intraoperative method with other radiographic hindfoot alignment measurements. METHODS: Thirty-seven patients (47 feet) with various foot and ankle conditions scheduled to undergo surgery were prospectively recruited. Before surgery, the Saltzman, long axial, and modified Méary views were taken in a controlled and standardized fashion. IOPPA views were obtained under simulated weight bearing conditions using C-arm fluoroscopy in the operating room before surgery. The relationship between the IOPPA view and the three radiographic hindfoot alignments was evaluated using Pearson's correlation. RESULTS: The mean hindfoot alignment angle was varus 3.50° (CI, varus 1.91 to 5.08) on the Saltzman view, varus 2.00° (CI, varus 0.60 to 3.39) on the long axial view, varus 0.13° (CI, valgus 1.41 to varus 1.67) on the modified Méary view, and varus 1.32° (CI, valgus 0.02 to varus 2.65) on IOPPA view. The IOPPA view and the three other hindfoot alignment views were found to be significantly correlated (r = 0.60 for the Saltzman view, r = 0.50 for the long axial view, r = 0.71 for the modified Méary view, P < .05). The intraobserver ICC (Intraclass Correlation Coefficient) value was 0.974 and interobserver ICC (Intraclass Correlation Coefficient) value was 0.988 for the IOPPA view (P < .001). CONCLUSION: There was a statistically significant correlation between the IOPPA view and the other three hindfoot alignment views. We also found that interobserver and intraobserver ICC values were excellent. This study proposes that the IOPPA view can be used as a reliable intraoperative assessment tool for hindfoot alignment. LEVEL OF EVIDENCE: Prospective study.

Factors affecting satisfaction in patients with a rotator cuff retear: CT arthrography-based study.

PURPOSE: The relationship between retear that may occur after rotator cuff repair and patient satisfaction is not well established. This study aimed to determine whether the types and size of the retear evaluated by computed tomography arthrography (CTA) influenced patient satisfaction. We also analyzed the patient factors that could affect patient satisfaction. PATIENTS AND METHODS: A total of 50 patients who were diagnosed with rotator cuff retear after undergoing arthroscopic rotator cuff repair were included in this study. All the patients were dichotomously classified into the satisfactory or dissatisfactory groups according to the patients' self-classifications. CTA was used to assess the attachment status of the footprint, detect retear on the medial side of the footprint of the repaired cuff, and determine the retear size. Demographic factors, including sex, age, occupation, dominant upper extremity, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation status, and functional shoulder score, were investigated. RESULTS: Thirty-nine patients were classified into the satisfactory group and 11 patients were classified into the dissatisfactory group. There were no differences in age, sex, occupation, dominant hand, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation, and duration of follow-up between the two groups. However, the postoperative American Shoulder and Elbow Surgeon (ASES) score (P < 0.01), visual analog scale (VAS) pain level (P < 0.01), anteroposterior (AP) length (P < 0.01), and area of the retear site (P < 0.01) were significantly different. CONCLUSION: The AP length and area of the retear site estimated using CTA were confirmed as the significant risk factors for dissatisfaction. However, the type of repaired rotator cuff judged by the attachment status of the footprint did not correlate with patient satisfaction. In addition, the postoperative VAS pain scale and ASES score was correlated with patient satisfaction.

Clinical and radiological results of early pin removal in pediatric radial neck fractures treated with stepwise percutaneous leverage technique.

OBJECTIVE: The aim of this study was to compare radiological and clinical results between early (≤3 weeks) and late (>3 weeks) removal of pins in patients treated with the stepwise percutaneous leverage technique for radial neck fractures. METHODS: 37 patients (aged 3-15) who underwent fixation with stepwise percutaneous leverage technique for Judet class III and class IV radial neck fractures between 2003 and 2019 were included in this retrospective study. Patients were divided into two groups according to the time of pin removal; 19 had early pin removal (≤3 weeks) and 18 had late pin removal (>3 weeks). The patients' radiological results were graded using the Metaizeau classification and their clinical results were evaluated by measuring their range of motion (ROM) and Mayo elbow performance scores (MEPS) at postoperative follow-ups. Statistical tests, including the Mann-Whitney U and Chi-square tests, were performed to compare the demographic factors and outcomes. RESULTS: The mean time of removal of pins for all patients was 21 (10-43) days. The mean time for early and late removal was 15.1 (10-21) and 27.6 (22-43) days, respectively. There was no statistically significant difference between groups radiologically according to the Metaizeau classification (P = .723). Furthermore, no statistically significant difference was found in the ROM (extension/flexion: P = .620, pronation/supination: P = .578) or MEPS (P = .695) between groups. CONCLUSION: This study has shown us that early removal of pins in patients with pediatric radial neck fractures treated with stepwise percutaneous leverage technique demonstrated good radiological and clinical results comparable to late pin removal. Level of Evidince: Level IV, Therapeutic Study.

Complications and outcomes of operative treatment for acute perilunate injuries: a systematic review.

We systematically reviewed the incidence of complications and outcomes of different surgical methods for acute perilunate injury in the MEDLINE, Scopus, Embase and Cochrane Library databases. Forty-three articles with 880 patients were included. The most common complications were arthritis (30%), carpal instability (15%), avascular necrosis of the lunate (12%), complex regional pain syndrome (11%), and nonunion or avascular necrosis of the scaphoid (9%). In the meta-analysis, the mean scapholunate gap was 1.7 mm in the closed surgery group and 2.3 mm in the open surgery group, which was a statistically significant difference. The mean flexion-extension arc of the wrist and modified Mayo wrist score were better in the closed surgery group than in the open surgery group. However, these findings may relate to different cohorts in terms of injury severity. Therefore, the causal relationship between closed surgery and better outcomes may be uncertain as less severe subluxations are more likely to be treated closed.

Trueness of stereolithography ZrO2 crowns with different build directions.

This study aims to measure the trueness of zirconia crowns with different build directions of materials fabricated using the stereolithography (SLA) method. The anatomic contour crown of prepped maxillary right first molar was designed using CAD software to obtain the standard tessellation language (STL) file. Two different build directions were set for the crowns using Materialize Magics software. One group was built with a margin base platform, while the other group was built in the direction opposite to the occlusal surface base platform. The 20 crown-shaped parts were printed. The STL files of scanned printing zirconia crowns were superimposed each segment by the 3D analysis software. The two groups were statistically analyzed using t-tests. Significant differences were found in the marginal and internal discrepancies between the groups. The build direction had a significant influence on the accuracy of the zirconia crown. The results indicate the most effective build direction for manufacturing SLA 3D-printed crowns.

Analysis of management efficacy in patients with heavy menstrual bleeding associated with antithrombotic therapy / 中华妇产科杂志

Objective: To evaluate different methods' efficacy of controlling acute bleeding and managing long-term menstruation in patients with heavy menstrual bleeding (HMB) associated with antithrombotic therapy. Methods: The clinical data of 22 cases with HMB associated with antithrombotic therapy admitted to Peking University People's Hospital from January 2010 to August 2022 were analyzed, aged 39 years old (26-46 years). Changes in menstrual volume, hemoglobin (Hb), and quality of life were collected after control of acute bleeding and long-term menstrual management. Menstrual volume was assessed by pictorial blood assessment chart (PBAC), and quality of life was assessed by menorrhagia multi-attribute scale (MMAS). Results: (1) Treatment of acute bleeding: of the 22 cases with HMB associated with antithrombotic therapy, 16 cases were treated in our hospital and 6 in other hospital for emergency bleeding; of the 16 cases treated in our hospital, 3 underwent emergency intrauterine Foley catheter balloon compression due to severe bleeding (Hb decreased by 20 to 40 g/L within 12 hours). Of the 22 cases with antithrombotic therapy-related HMB, 15 (including 2 cases with severe bleeding) underwent emergency aspiration or endometrial resection, and intraoperative placement of levonorgestrel-releasing intrauterine system (LNG-IUS) followed by a significant reduction in bleeding volume; 3 cases had controlled acute bleeding after rivaroxaban dose reduction and continued observation; 2 cases were given gonadotropin-releasing hormone agonists to control acute bleeding in other hospital, of which 1 case was temporarily treated with periodic blood transfusion, and the other one patient underwent total hysterectomy; and 2 cases had temporary amenorrhea with oral mifepristone after intrauterine balloon compression or oral norethindrone. (2) Long-term menstrual management: of the 22 cases with antithrombotic therapy-related HMB, 15 had LNG-IUS placement and 12 had LNG-IUS placement for 6 months, and menstrual volume was significantly reduced [PBAC scores were 365.0 (272.5-460.0) vs 25.0 (12.5-37.5), respectively; Z=4.593, P<0.001], Hb was significantly increased [91.5 g/L (71.8-108.2 g/L) vs 128.5 g/L (121.2-142.5 g/L); Z=4.695, P<0.001], and quality of life was significantly improved [MMAS scores were 415.0 (327.5-472.5) vs 580.0 (570.0-580.0), respectively; Z=-3.062, P=0.002] before placement compared with 6 months after placement. Three rivaroxaban dose reduction patients' PBAC scores decreased by 20 to 35 but remained >100, and perceived quality of life did not change significantly. Two cases with temporary amenorrhea treated with oral mifepristone felt significantly improved quality of life, and the MMAS scores increased by 220 and 180, respectively. Conclusion: Intrauterine Foley catheter balloon compression, aspiration or endometrial ablation could be used to control acute bleeding in patients with antithrombotic therapy-related HMB, and LNG-IUS for long-term management could reduce menstrual volume, increase hemoglobin, and improve the quality of life of patients.

Protective Effect and Mechanism of Kuntai Capsule on Angiotensin II -Induced Hypertension in Ovariectomized Rats / 中国结合医学杂志

OBJECTIVE@#To explore the protective effect and mechanism of Kuntai (KT) Capsule on angiotensin II (Ang II)-induced hypertension in ovariectomized (OVX) rats.@*METHODS@#Fifty-four rats were randomly divided into 6 groups according to a random number table, 9 in each group: control, OVX sham+Ang II, OVX, OVX+Ang II, OVX+Ang II +E2, and OVX+Ang II +KT. OVX rats model was constructed by retroperitoneal bilateral ovariectomy. After 4 weeks of pretreatment with KT Capsule [0.8 g/(kg·d) and 17- β -estradiol (E2, 1.2 mg/(kg·d)] respectively, Ang II was injected into a micro-osmotic pump with a syringe to establish a hypertensive rat model. Blood pressure of rat tail artery was measured in a wake state of rats using a non-invasive sphygmomanometer. Blood pressure changes were compared between the intervention groups (OVX+Ang II +KT, OVX+Ang II +E2) and the negative control group (OVX+Ang II). Serum malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were detected respectively. The expressions of oxidative stress-related protein superoxide dismutase2 (SOD2) and anti-thioredoxin (TRX), autophagy marker protein [beclin1, light chain (LC) 3 II/I ratio and autophagy canonical pathway protein phosphatidylinositol 3-kinase (PI3K)/serine/threonine kinase (AKT)-mammalian target of rapamycin (mTOR)] were evaluated by Western blotting.@*RESULTS@#Compared with the OVX+Ang II group, the systolic blood pressure of OVX+Ang II +KT group was significantly lowered (P<0.05) but not the diastolic blood pressure. Besides, SOD2 and TRX protein levels in mycardial tissues were significantly reduced in the OVX+Ang II +KT group compared with the OVX+Ang II group (P<0.05). Oxidative stress serum markers MDA and SOD were down- and up-regulated in the OVX+Ang II +KT group, respectively (P<0.05). Compared with OVX+Ang II group, the levels of cardiac proteins beclin-1 and LC3II/LC3 I in OVX+Ang II +KT group were also up-regulated (P<0.05), and the expression levels of p-PI3K, p-AKT and mTOR protein were down-regulated (P<0.05).@*CONCLUSION@#KT could protect blood pressure of Ang II-induced OVX rats by inhibiting oxidative stress and up-regulating protective autophagy.

Effect of Different Software Programs on the Accuracy of Dental Scanner Using Three-Dimensional Analysis.

This in vitro study aimed to evaluate the 3D analysis for complete arch, half arch, and tooth preparation region by using four analysis software programs. The CAD reference model (CRM; N = 1 per region) and CAD test models (CTMs; N = 20 per software) of complete arch, half arch, and tooth preparation were obtained by using scanners. For both CRM and CTMs, mesh data other than the same area were deleted. For 3D analysis, four analysis software programs (Geomagic control X, GOM Inspect, Cloudcompare, and Materialise 3-matic) were used in the alignment of CRM and CTMs as well as in the 3D comparison. Root mean square (RMS) was regarded as the result of the 3D comparison. One-way analysis of variance and Tukey honestly significant difference tests were performed for statistical comparison of four analysis software programs (α = 0.05). In half-arch and tooth preparation region, the four analysis software programs showed a significant difference in RMS values (p < 0.001), but in complete-arch region, no significant difference was found among the four software programs (p = 0.139). As the area of the virtual cast for 3D analysis becomes smaller, variable results are obtained depending on the software program used, and the difference in results among software programs are not considered in the 3D analysis for complete-arch region.

The Trans-omics Landscape of COVID-19

System-wide molecular characteristics of COVID-19, especially in those patients without comorbidities, have not been fully investigated. We compared extensive molecular profiles of blood samples from 231 COVID-19 patients, ranging from asymptomatic to critically ill, importantly excluding those with any comorbidities. Amongst the major findings, asymptomatic patients were characterized by highly activated anti-virus interferon, T/natural killer (NK) cell activation, and transcriptional upregulation of inflammatory cytokine mRNAs. However, given very abundant RNA binding proteins (RBPs), these cytokine mRNAs could be effectively destabilized hence preserving normal cytokine levels. In contrast, in critically ill patients, cytokine storm due to RBPs inhibition and tryptophan metabolites accumulation contributed to T/NK cell dysfunction. A machine-learning model was constructed which accurately stratified the COVID-19 severities based on their multi-omics features. Overall, our analysis provides insights into COVID-19 pathogenesis and identifies targets for intervening in treatment.

Correlation between patient-reported outcome measures and Single Assessment Numerical Evaluation score in patients treated with a volar locking plate for a distal radial fracture.

AIMS: The aim of this study was to compare patient-reported outcome measures (PROMs) and the Single Assessment Numerical Evaluation (SANE) score in patients treated with a volar locking plate for a distal radial fracture. METHODS: This study was a retrospective review of a prospective database of 155 patients who underwent internal fixation with a volar locking plate for a distal radial fracture between August 2014 and April 2017. Data which were collected included postoperative PROMs (Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) and Patient-Rated Wrist Evaluation (PRWE)), and SANE scores at one month (n = 153), two months (n = 155), three months (n = 144), six months (n = 128), and one year (n = 73) after operation. Patients with incomplete data were excluded from this study. Correlation and agreement between PROMs and SANE scores were evaluated. Subgroup analyses were carried out to identify correlations according to variables such as age, the length of follow-up, and subcategories of the PRWE score. RESULTS: The Pearson correlation coefficient (r) between PROMs and SANE scores was -0.76 (p < 0.001) for DASH and -0.72 (p < 0.001) for PRWE, respectively. Limits of agreement between PROMs and '100-SANE' scores were met for at least 93% of the data points. In subgroup analysis, there were significant negative correlations between PROMs and SANE scores for all age groups and for follow-up of more than six months. The correlation coefficient between PRWE subcategories and SANE score was -0.67 (p < 0.001) for PRWE pain score and -0.69 (p < 0.001) for PRWE function score, respectively. CONCLUSION: We found a significant correlation between postoperative SANE and PROMs in patients treated with a volar locking plate for a distal radial fracture. The SANE score is thus a reliable indicator of outcome for patients who undergo surgical treatment for a radial fracture. Cite this article: Bone Joint J 2020;102-B(6):744-748.

Comparison of clinical fit of three-unit zirconia fixed prostheses fabricated using chairside and labside CAD/CAM systems.

The purpose of this study was to assess the clinical fit provided by EZIS system, the newly commercialized chairside CAD/CAM system. Prostheses were fabricated with the chairside CAD/CAM system (CS) and labside CAD/CAM system (LS) and marginal, axial, and occlusal fit of the prostheses were compared and analyzed by using replica technique. CS group presented significantly lower fit in all the three fits compared to LS group. Differences in marginal fit, axial fit, and occlusal fit were 12.57 µm (P < 0.001), 3.32 µm (P < 0.05), and 17.20 µm (P < 0.05), respectively. Newly commercialized EZIS system yielded clinically feasible fit; however, further researches covering its biomechanical, physiological, stability aspects are required to promote active clinical use.

Displacement of Customized Abutments Designed on a Working Cast and in the Oral Cavity: A Comparative In Vivo Study.

PURPOSE: To compare abutment displacement between the virtual, customized abutment that was designed on a cast and the customized abutment prepared in the oral cavity. MATERIALS AND METHODS: Eleven patients were selected for a single posterior implant prosthetic treatment. The impression was obtained using the closed tray impression method with a vinyl polysiloxane material using a custom tray. The standard tessellation language files of the customized abutment that was designed using the computer-aided design system and acquired with an intraoral scanner in the oral cavity were superimposed and analyzed for distance and angle displacement using the three-dimensional inspection analysis program (Geomagic Control X). In the statistical analysis, distance and angle displacement values were analyzed with the Kruskal-Wallis H test (α = 0.05), and a post hoc comparison was performed using the Mann-Whitney U-test and Bonferroni correction method. RESULTS: The mean distance and angle displacement of the 15 customized abutments were 89.52 ± 66.86 µm and 0.83 ± 1.21°, respectively. There were significant differences in distance displacement (p < 0.001), and angle displacement (p < 0.001) among the 15 customized abutments, and there were no significant differences in angle displacement along the 4 directions (p = 0.735). CONCLUSIONS: The displacement values of the customized abutments evaluated in the oral cavity differed significantly from patient to patient.

Prognostic factors of acute ankle sprain: Need for ultrasonography to predict prognosis.

BACKGROUND: Ankle sprains are one of the most common musculoskeletal injuries. To guide management decisions, a clear insight into the relevant subgroups of patients with a potentially better or worse prognosis is important. This study aimed to evaluate injury severity, using ultrasonography (US), as a prognostic factor of acute ankle sprain and other possible factors including age, sex, body mass index (BMI), level of job activity, and level of sports activity. MATERIALS AND METHODS: We retrospectively reviewed 28 patients with acute ankle sprain who reported at initial examination with an acutely twisted ankle. All patients had received a standard physical examination, radiography and standard ultrasound, to diagnose specific ligament injuries and their ankle sprain had been treated using standard conservative management. Various data including age, sex, BMI, level of sports activity, level of daily job activity, and final functional score (Foot and Ankle Outcome Scores, FAOS) were obtained. Mean comparison and correlations were used to assess risk factors. Risk factors associated with functional outcomes were evaluated using a multiple linear regression test. RESULTS: At final follow-up as 1 year after injury, FAOS differed significantly for injury severity, age, and BMI. There were no significant differences in sex, job activity, and exercise levels. The factor most affecting FAOS for both pain (FAOS-Pain) and symptoms (FAOS-Sx) was the number of completely torn ligaments. Age was the most important factor affecting the FAOS-Daily Living Activity (ADL). BMI was the most important factor for sports activity level (FAOS-Sports). Age and the number of completely torn ligaments were both important to FAOS-Sports and quality of life (FAOS-QOL). CONCLUSION: The severity of injury, defined using US, was a prognostic factor for long-term outcome following acute ankle sprain. Therefore, US imaging of acute ankle ligament injury may be important to predict prognosis of acute ankle sprain.

Seroprevalence of and Identification of Risk Factors in China / 生物医学与环境科学（英文）

Serum samples were tested for IgG antibodies using indirect immunofluorescence assays. We then analyzed associated risk factors. Serum samples were considered positive when reactive at a dilution of more than 1:320. Differences between groups and risk factors associated with exposure were statistically analyzed using Chi-square tests and the generalized linear model. 122 of 1,260 samples (9.68%) were positive for infection. The infection rate ranged from 0% to 30.43% and differed significantly among age groups ( < 0.01); infection rate in the 50-59 years group was significantly higher than that in other age groups. The seroprevalence of varied significantly among sites within the four provinces, and the infection rate of field workers was significantly higher than that of urban workers.

Comparison of Tightening Screw Accuracy of Electronic Torque Drivers.

PURPOSE: To compare the tightening torque accuracy of three electronic torque drivers. MATERIALS AND METHODS: Three electronic torque drivers were assessed using two measurement methods-pure output torque (POT) and clinical output torque (COT). For both methods, assessments were performed at set torques of 10, 20, 30, and 40 Ncm, 10 times for each setting, with each driver tested. Appropriate statistical analysis was performed according to data distribution (ie, normal vs non-normal) (α = .05). RESULTS: POT was significantly higher than COT at a set torque of 30 Ncm (P < .001). CONCLUSION: In fastening an implant screw at 30 Ncm, the operator should also consider the output torque generated in the electronic torque driver.

Prediction of the learning curves of 2 dental CAD software programs.

STATEMENT OF PROBLEM: Dental clinical procedures are being replaced by digital workflows. Therefore, the time necessary to learn dental computer-aided design (CAD) software to achieve a change in the digital workflow should be evaluated. PURPOSE: The purpose of this study was to predict the learning curve according to the type of dental CAD software with the Wright model and to determine the rate of improvement in the learner's working time with iterative learning. MATERIAL AND METHODS: A total of 40 participants with various degrees of experience with dental computer-aided design and computer-aided manufacturing (CAD-CAM) systems were recruited. The 4 specified steps of a custom abutment design were performed with 3DSystem CAD software (Daesung) and exocad DentalCAD (exocad GmbH) software and were repeated 3 times in stages. The times were analyzed with repeated-measures 1-factor and 2-factor analyses. The learning time for 300 design iterations was estimated by applying the Wright model formula, and the 300-repetition times were analyzed with the Mann-Whitney U test (α=.05). RESULTS: exocad had a longer mean learning time than the 3DSystem. The overall change with repeated learning was significantly different (P<.001), and all differences were found in the first to third iterations. Software-dependent differences were also observed (P=.005). The Mann-Whitney U test also revealed a significant difference between the 2 software programs (P=.015), but no significant difference was found after the 56th iteration (57th iteration: P=.051). CONCLUSIONS: As the time reduction patterns for iterative learning differ depending on the type of CAD software, the learning curves may differ according to the type of software. As the operator's skill increased through iterative learning, the differences in learning times between the software programs gradually disappeared.

Evaluating usability of and satisfaction with two types of dental CAD software

PURPOSE: This study evaluated the usability of and satisfaction with two types of computer-aided design (CAD) software among users who had experience with dental implant CAD software and those who did not. MATERIALS AND METHODS: Dental technicians (n = 20) who had previous experience with dental implant CAD Software and students from the College of Dentistry (n = 12) who had never designed implant custom abutments were asked to evaluate two types of CAD Software, Exocad and Deltanine. In addition, the participants were asked to fill out a structured questionnaire (Section 1: Entering basic information and retrieving files; Section 2: Setting conditions before abutment design; Section 3: Setting abutment design; and Section 4: Overall satisfaction). For the statistical analysis of the collected data, Mann-Whitney U test was used (α = .05). RESULTS: The ease of design and satisfaction with the implant CAD Software, evaluated with respect to 21 statements divided into four Stages, were significantly higher for Exocad in both groups for Secion 1. For Sections 2 and 3, participants with experience evaluated Deltanine to be significantly better. For Section 4, both groups evaluated Exocad Software to be better. CONCLUSION: Overall, the Exocad Software was evaluated as having better usability and offering greater satisfaction. However, in terms of performance in the core of the design process, i.e. Sections 2 and 3, Deltanine was rated higher by the experienced users. Thus, if the user interface design parts are supplemented, Deltanine CAD Software could be put to a wider use in clinics.

Humerus Shaft Fractures Occurring in Fly Fishing Boat Riding: Injury Scene Analysis / 대한스포츠의학회지

PURPOSE: The aim of this study was to analyze an injury scene during fly fish boat riding (FBR).METHODS: We conducted survey on 12 patients who had humerus shaft fractures during FBR between 2011 and 2016 at three university-based emergency rooms. Individual information, injury mechanism, classification of humerus shaft fracture, and combined injury were recorded from medical document and telephone interview.RESULTS: The injury happened when the kite was turned over and fall into the water in 10 patients (82%); the kite was turned over in the air in one patient (9%), and a leash between kite and boat was broken in one patient (9%). All patients showed 12-B1 or 12-B3 type distal humerus shaft fracture. And there were combined contralateral distal humeral shaft fractures in two patients, vertebral compression fracture in one patient, and radial nerve injury in four patients.CONCLUSION: Riding position and injury mechanism such as turning over may affect distal humerus shaft fractures with butterfly fragment during FBR.