• 제목/요약/키워드: paired-t tests

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Accuracy of three-dimensional cephalograms generated using a biplanar imaging system

  • Park, Ha-Yeon;Lee, Jae-Seo;Cho, Jin-Hyoung;Hwang, Hyeon-Shik;Lee, Kyung-Min
    • 대한치과교정학회지
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    • 제48권5호
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    • pp.292-303
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    • 2018
  • Objective: Biplanar imaging systems allow for simultaneous acquisition of lateral and frontal cephalograms. The purpose of this study was to compare measurements recorded on three-dimensional (3D) cephalograms constructed from two-dimensional conventional radiographs and biplanar radiographs generated using a new biplanar imaging system with those recorded on cone-beam computed tomography (CBCT)-generated cephalograms in order to evaluate the accuracy of the 3D cephalograms generated using the biplanar imaging system. Methods: Three sets of lateral and frontal radiographs of 15 human dry skulls with prominent facial asymmetry were obtained using conventional radiography, the biplanar imaging system, and CBCT. To minimize errors in the construction of 3D cephalograms, fiducial markers were attached to anatomical landmarks prior to the acquisition of radiographs. Using the 3D $Ceph^{TM}$ program, 3D cephalograms were constructed from the images obtained using the biplanar imaging system (3D $ceph_{biplanar}$), conventional radiography (3D $ceph_{conv}$), and CBCT (3D $ceph_{cbct}$). A total of 34 measurements were obtained compared among the three image sets using paired t-tests and Bland-Altman plotting. Results: There were no statistically significant differences between the 3D $ceph_{biplanar}$ and 3D $ceph_{cbct}$ measurements. In addition, with the exception of one measurement, there were no significant differences between the 3D $ceph_{cbct}$ and 3D $ceph_{conv}$ measurements. However, the values obtained from 3D $ceph_{conv}$ showed larger deviations than those obtained from 3D $ceph_{biplanar}$. Conclusions: The results of this study suggest that the new biplanar imaging system enables the construction of accurate 3D cephalograms and could be a useful alternative to conventional radiography.

수중 동요 훈련이 뇌졸중 환자의 생리학적 소비지수와 보행 능력에 미치는 효과 분석 (An Analysis of Effects of Water Perturbation Exercise on Physiological Cost Index and Gait Ability in Stroke Patients)

  • 박승규;박삼헌
    • 대한통합의학회지
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    • 제4권3호
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    • pp.39-47
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    • 2016
  • PURPOSE : This study attempts to find the effects of water perturbation exercise performed on stroke patients in their physiological cost index and gait ability tests. METHOD : The subjects were 30 stroke patients, water perturbation exercise group was performed 3 day per week, for 40 minutes a day, for a period of eight weeks. The physiological cost index and gait of all subjects were assessed by using the polar, 6 Minute Walk Test (6MWT), and 10 meter Walk Test(10mWT) at pre training and post training. Paired t-test was used to analyze change before and after intervention in group. Pearson's correlation was used to analyze correlation of all variables. RESULT : Water perturbation exercise group showed increased physiological cost index. Water perturbation exercise increased gait ability, showing a significant difference. Showing the correlation between the relatively high amount between physiological cost index and 6 minutes walking test. CONCLUSION : From the result of the study, we found that water perturbation exercise was effective in improving physiological cost index and gait ability. The patient is considered to be used by itself to involve the treatment and the risk of falling from the lowered state into the treatment method for the intensive treatment of stroke patients to be useful in improving the cardiovascular system and ability to walk. Through underwater training for stroke patients in the future on the basis of this study it is considered to require additional clinical studies on the impact on daily living and quality of life of stroke patients.

수직점프 시 비탄력 테이핑이 발목 발등굽힘과 하퇴삼두근의 근활성도에 미치는 영향 (Effect of Non-elastic Taping on Ankle Dorsiflexion and Activity of the Triceps Surae Muscles While Vertical Jumping)

  • 김근수;원종혁;정도영
    • 대한물리의학회지
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    • 제11권4호
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    • pp.11-17
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    • 2016
  • PURPOSE: There are several standard interventions for managing Achilles tendinitis, including eccentric exercise and calf muscle stretches, orthoses, electrotherapy, and taping. However, no study has determined the effect of non-elastic taping on deloading the Achilles tendon while vertical jumping. Therefore, this study determined the effect of non-elastic taping on ankle dorsiflexion and the triceps surae muscle activity while vertical jumping in healthy subjects. METHODS: The study recruited 17 participants. A motion analysis system was used to measure the angle of ankle dorsiflexion and wireless surface electromyography was used to measure the soleus and gastrocnemius activities while vertical jumping. Non-elastic taping was applied on randomized leg side. All subjects performed maximal effort vertical jumps without and with non-elastic taping, with three trials for each condition. The mean peak dorsiflexion and muscle activities during the three trials were calculated and paired t-tests were used to compare the mean values without and with non-elastic taping. Significance was defined as (p<.05). RESULTS: The maximum angle of ankle dorsiflexion and activity of the gastrocnemius muscle decreased significantly when non-elastic tape was applied (p<.05), while there was no significant difference in the soleus activity between no-taping and taping (p>.05). CONCLUSION: We introduce non-elastic taping as a method to decrease maximum ankle dorsiflexion and gastrocnemius activity while vertical jumping.

유리단 국소의치의 지대치 운동에 관한 생체학적 연구 (IN VIVO STUDY ON ABUTMENT TOOTH MOVEMENT FOR DISTAL EXTENSION REMOVABLE PARTIAL DENTURES)

  • 이종엽;김광남;장익태
    • 대한치과보철학회지
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    • 제28권1호
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    • pp.43-61
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    • 1990
  • The laser reflexion method is a new technique which permits precise contactless measurement and observation of tooth mobility as well as tooth movement. The purposes of this study were to clarify the reliability of the laser reflexion method in clinical application and to measure the abutment tooth movement according to clasp design. This study was designed to determine 1) How much a bending movement of the impression plate stand affects the position of the reflexion pattern and how precise the patient bites into plate 2) Which clasp design causes greater movement of the abutment tooth. Under medium and maximum bite forces, tests were performed on central loading position which was 13mm distal to terminal abutment tooth of distal extension removable partial denture. The movement in the mesiodistal and buccolingual directions was measured. The Duncan's New Multiple-Range test was used to compare the means for the four castings under each direction-load combination; and the paired sample t-test was for medium and maximum bite forces. From this experiment, the following results were obtained. 1. The Roach clasp, the combination clasp, the RPI clasp, and the Akers clasp did not significantly differ in their effects on buccolingual movement of the abutment tooth. 2. The direction of abutment tooth movement was not significantly altered by clasp design and all abutment tooth movements were oriented distobuccally. 3. Under medium bite force, the Akers clasp caused greater distal movement of the abutment tooth than did the combination clasp and the RPI clasp. Under maximum bite force, the Akers clasp caused greater distal movement of the abutment tooth than did the RPI clasp. 4. The testing apparatus and procedures used in this study(laser reflexion method) proved to be reliable in clinical application.

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Measuring abutment convergence angles using stereovision dental image processing system

  • Yang, Hong-Seok;Park, Ji-Man;Han, Jung-Suk;Lee, Jai-Bong;Kim, Sung-Hun;Yeo, In-Sung
    • The Journal of Advanced Prosthodontics
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    • 제6권4호
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    • pp.259-265
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    • 2014
  • PURPOSE. The purpose of this study was to develop a dental image processing system using a three-dimensional (3D) camera and stereovision technology. The reliability of the system for measuring axial wall convergence angles was evaluated. MATERIALS AND METHODS. The new system predicted 3D coordinate points from 2D images and calculated distances and angles between points. Two examiners measured axial wall convergence angles for seven artificial abutments using a traditional tracing-based method (TBM) and the stereovision-based method (SVBM). Five wax abutment models of simplified abutment forms were made and axial wall convergence angles of wax models were measured by both methods. The data were statistically analyzed at the level of significance, 0.05. RESULTS. Intraclass correlation coefficients showed excellent intra-examiner and inter-examiner reliabilities for both methods. Bland-Altman plots and paired t-tests showed significant differences between measurements and true values using TBM; differences were not significant with SVBM. CONCLUSION. This study found that the SVBM reflected true angle values more accurately than a TMB and illustrated an example of 3D computer science applied to clinical dentistry.

Effectiveness of an Intervention Program on Knowledge of Oral Cancer among the Youth of Jazan, Saudi Arabia

  • Quadri, Mir Faeq Ali;Saleh, Sanaa Mahmoud;Alsanosy, Rashad;Abdelwahab, Siddig Ibrahim;Tobaigy, Faisal Mohamed;Maryoud, Mohamed;Al-Hebshi, Nezar
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권5호
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    • pp.1913-1918
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    • 2014
  • Background: The study is the first of its kind to be conducted in Saudi Arabia (KSA), aiming to analyze the effectiveness of an intervention program in improving the knowledge of oral cancer among the youth. Materials and Methods: A total of 1,051 young Saudis (57% males and 43% females with a mean age of $20.4{\pm}1.98$) were selected using multi-stage cluster sampling. Knowledge assessment was accomplished using a closed-ended questionnaire which was subjected to reliability tests. Prevalence of risk factors in relation to gender was analyzed using the chi-squared test. Effectiveness was calculated by comparing the pre- and post-intervention means, using the two-tailed paired t-test. Multiple logistic regression was employed in order to determine factors associated with awareness of risk habits, signs/symptoms and prevention of oral cancer. The significance level in this study was set at 0.05. Results: Females were seen to be more into the habit of sheesha smoking (3.3% rather than the use of other forms of risk factors. Prevalence of diverse risk factors such as cigarette smoking (20%), sheesha (15.3%), khat (27%) and shamma (9%) was seen among males. Gender and the use of modifiable risk factors among the study sample were significantly (p<0.001) associated with effectiveness of the intervention. The intervention program was highly effective (p<0.001) in improving the knowledge of oral cancer among the youth in Jazan, KSA. Multivariate analysis revealed that age and gender are the most significant factors affecting knowledge. Conclusions: The study gives a direction for further public health initiatives in this oral cancer prone region.

Accuracy of three-dimensional printing for manufacturing replica teeth

  • Lee, Keun-Young;Cho, Jin-Woo;Chang, Na-Young;Chae, Jong-Moon;Kang, Kyung-Hwa;Kim, Sang-Cheol;Cho, Jin-Hyoung
    • 대한치과교정학회지
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    • 제45권5호
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    • pp.217-225
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    • 2015
  • Objective: Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Methods: Fifty extracted molar teeth were selected as samples. They were scanned to generate high-resolution 3D surface model stereolithography files. These files were converted into physical models using two types of 3D printing technologies: Fused deposition modeling (FDM) and PolyJet technology. All replica teeth were scanned and 3D images generated. Computer software compared the replica teeth to the original teeth with linear measurements, volumetric measurements, and mean deviation measurements with best-fit alignment. Paired t-tests were used to statistically analyze the measurements. Results: Most measurements of teeth formed using FDM tended to be slightly smaller, while those of the PolyJet replicas tended to be slightly larger, than those of the extracted teeth. Mean deviation measurements with best-fit alignment of FDM and PolyJet group were 0.047 mm and 0.038 mm, respectively. Although there were statistically significant differences, they were regarded as clinically insignificant. Conclusions: This study confirms that FDM and PolyJet technologies are accurate enough to be usable in orthodontic diagnosis and treatment.

Effects of vitamin D supplementation on metabolic indices and hs-CRP levels in gestational diabetes mellitus patients: a randomized, double-blinded, placebo-controlled clinical trial

  • Yazdchi, Roya;Gargari, Bahram Pourghassem;Asghari-Jafarabadi, Mohammad;Sahhaf, Farnaz
    • Nutrition Research and Practice
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    • 제10권3호
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    • pp.328-335
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    • 2016
  • BACKGROUND/OBJECTIVES: Vitamin D plays an important role in the etiology of gestational diabetes mellitus (GDM). This study evaluated the effect of vitamin D supplementation on metabolic indices and hs-C-reactive protein (CRP) levels in GDM patients. SUBJECTS/METHODS: The study was a randomized, placebo-controlled, double-blinded clinical trial. Seventy-six pregnant women with GDM and gestational age between 24-28 weeks were assigned to receive four oral treatments consisting of 50,000 IU of vitamin $D_3$ (n = 38) or placebo (n = 38) once every 2 weeks for 2 months. Fasting blood glucose (FG), insulin, HbA1c, 25-hydroxyvitamin D, lipid profile, hs-CRP, and homeostasis model assessment-insulin resistance (HOMA-IR) were measured before and after treatment. Independent and paired t-tests were used to determine intra- and intergroup differences, respectively. ANCOVA was used to assess the effects of vitamin D supplementation on biochemical parameters. RESULTS: Compared with the placebo group, in the vitamin D group, the serum level of 25-hydroxyvitamin D increased (19.15 vs. -0.40 ng/ml; P < 0.01) and that of FG (-4.72 vs. 5.27 mg/dl; P = 0.01) as well as HbA1c (-0.18% vs. 0.17%; P = 0.02) decreased. Improvements in the lipid profiles were observed in the vitamin D group, but without statistical significance. Significant increases in concentrations of hs-CRP, FG, HbA1c, total cholesterol, and LDL cholesterol were observed in the placebo group. No significant change in fasting insulin and HOMA-IR was observed in either group. CONCLUSIONS: In GDM patients, vitamin D supplementation improved FG and HbA1c but had no significant effects on lipid profile or hs-CRP.

Effects of Deep Abdominal Muscle Strengthening Exercises on Pulmonary Function and the Ability to Balance in Stroke Patients

  • Kang, Jeong-Il;Kim, Beom-Ryong;Park, Seung-Kyu;Yang, Dae-Jung;Jeong, Dae-Keun;Kim, Je-Ho
    • The Journal of Korean Physical Therapy
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    • 제27권4호
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    • pp.258-263
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    • 2015
  • Purpose: This study investigated effects of deep abdominal muscle strengthening exercises on pulmonary function and the ability to balance in stroke patients and was conducted to propose an exercise program for improving cardiovascular function. Methods: Study subjects were 20 patients with hemiplegia due to stroke, who were divided into the deep abdominal muscle strengthening exercise group (experimental group), 10, and the control group, 10. Pulmonary function tests measured FVC and FEV1, dynamic balance ability was measured using TUG. Static and dynamic balance ability was measured using BBS. The experimental group performed exercises during a period of 6 weeks, 5 times a week for 40 minutes, whereas the control group did not participate in regular exercise. The difference before and after the exercise was compared using paired t-test, difference in exercise before and after between groups was ANCOVA and level of significance was set at ${\alpha}=0.05$. Results: The changes in FVC and FEV1 within the group showed a significant difference only in the experimental group (p<0.001) (p<0.01), between-group difference was statistically significant only in FVC and FEV1 changes in the experimental group (p<0.001). The TUG changes within the group showed a significant difference in the experimental group and control group (p<0.001) (p<0.05), while BBS changes showed a significant difference only in the experimental group. Between-group difference was statistically significant only in TUG and BBS changes in the experimental group. The experimental group showed a more effective significant difference than the control group (p<0.001). Conclusion: Can exercise involving a deep abdominal muscle strengthening program be applied in patients with stroke with difficulty in control of trunk and decreased breathing ability?

The Reliability of a Pediatric Balance Scale Based on the Raters' Clinical Work Experience and Test Experience

  • Kim, Gi-Won;Ko, Joo-Yeon;Baek, Soon-Gi
    • The Journal of Korean Physical Therapy
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    • 제22권6호
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    • pp.35-42
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    • 2010
  • Purpose: To investigate the rater reliability of a Pediatric Balance Scale (PBS) for children with cerebral palsy, and to investigate possible differences among raters according to their clinical work experience and testing experience. Methods: Study participants included 18 children with spastic cerebral palsy who could walk. They were instructed by pediatric physical therapists, two of whom had ten years of clinical work experience and two who had less than one year of experience. The children's ability to achieve physical balance was videotaped for PBS items. The raters watched the tapes and evaluated each child twice. Rater reliability was analyzed using the intraclass correlation coefficient (ICC). Differences between experienced and novice raters were analyzed using a paired t-test. The statistical significance level was set to 0.05. Results: The total PBS scores averaged 45.78~48.00 and 45.72~47.67 for first and second tests. Intra-rater reliability was very high (ICC=0.89~0.99), and the repeated measurement coincidence was high (p>0.05). Inter-rater reliability was high (ICC=0.83~0.84), but there was a bit of a difference in the coincidence (p<0.05). The experienced raters' reliability and coincidence were higher than those of the novices, and there were differences in reliance and coincidence between experienced and novice raters (p<0.05). Conclusion: Inter-rater and intra-rater reliability is very high. However, rater reliability showed defferences depending on clinical work experience and testing experience. When testing pediatric patients with the PBS, the rater's clinical experience and test experience may affect the test results.