• International Journal of Highway Engineering
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• v.7 no.2 s.24
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• pp.69-76
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• 2005

While the repeated traffic loading accumulates the damage of asphalt pavement, the damage has being healed during rest periods. And then, this healing enhances the fatigue life of asphalt pavement. A method was developed to determine the healing rate of asphalt mixture in terms of recovered dissipated creep strain energy (DCSE) per unit time, and the healing properties of four different asphalt mixtures were evaluated. The test procedure consists of repeated loading test and periodical resilient modulus tests. A normalized healing rate in terms of $DCSE/DCSE_{applied}$ was defined to evaluate the healing properties independently of the amount of damage incurred in the mixture. From the test results, it was concluded that the healing rates of asphalt mixtures were increased exponentially as the temperature was increased and more affected by the structural characteristics of mixture such as asphalt content than the binder characteristics such as the polymer modification.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.4
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• pp.258-265
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• 2020

Objectives: Despite advances in maxillofacial surgery, impaired bone healing remains a concern for surgical teams. Many studies have evaluated the effects of sildenafil and pentoxifylline on bone healing. However, their effects on healing of bone fractures have not been well investigated. This study aimed to assess the effects of the phosphodiesterase inhibitors sildenafil and pentoxifylline on healing of mandibular fractures in rats. Materials and Methods: A total of 60 rats were randomly divided into six groups of 10. Mandibular fracture was induced in all rats. After the surgical procedure, group C1 received saline, group S1 received 10 mg/kg sildenafil and group P1 received 50 mg/kg pentoxifylline. The rats were sacrificed after 1 week. Groups C4, S4, and P4 received pharmaceutical therapy as in groups C1, S1, and P1 but were sacrificed after 4 weeks. The samples then underwent histological analysis. Results: The mean rate of bone healing of mandibular fractures in groups S1 and P1 was significantly higher than in group C1 at 1 week (P<0.001). The mean rate of bone healing of mandibular fractures in group P1 was higher than in group S1 at 1 week (P=0.04). The mean rate of bone healing of mandibular fractures in groups S4 (P=0.001) and P4 (P=0.004) was significantly higher than in group C4 at 4 weeks, but no significant difference was noted in the rate of healing between groups P4 and S4 (P=0.53). Conclusion: Sildenafil and pentoxifylline can be used as adjuncts to enhance bone healing in rats.

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.262-270
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• 2016

Objectives: This study aimed to evaluate the healing rate of non-surgical endodontic treatment between C-shaped and non-C-shaped mandibular second molars. Materials and Methods: Clinical records and radiological images of patients who had undergone endodontic treatment on mandibular second molars between 2007 and 2014 were screened. The periapical index scoring system was applied to compare healing outcomes. Information about preoperative and postoperative factors as well as the demographic data of the patients was acquired and evaluated using chi-square and multinomial logistic regression tests. Results: The total healing rate was 68.4%. Healing rates for the mandibular second molar were 70.9% in C-shaped canals (n = 79) and 66.6% in non-C-shaped ones (n = 117). The difference was not statistically significant. Conclusions: The presence of a C-shaped canal in the mandibular second molar did not have a significantly negative effect on healing after treatment. Instead, proper pulpal diagnosis and final restoration were indicated as having significantly greater influence on the healing outcomes of C-shaped and non-C-shaped canals, respectively.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.383-388
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• 2021

In this study, constant head water permeability test was adopted to evaluate self-healing performance of mortars containing inorganic healing materials which consist of blast furnace slag, sodium sulfate and anhydrite. Clinker powder and sand replaced for a part of cement and fine aggregates. On constant head water permeability test for self-healing mortars, unit water flow rate of mortar specimens were measured according to crack width and healing period. As a result of evaluating the healing performance of self-healing mortar, it was confirmed that with the initial crack width of 0.3mm, the healing rate at healing period of 28 days increased by more than 30%p compared to plain mortar, greatly improving the healing performance. Furthermore, the coefficient(α) which was estimated from the relationship between crack width and unit water flow rate was used for calculating equivalent crack width. By analyzing the correlation of healing rate and equivalent crack width, the time and initial crack width attaining healing target crack width were predicted.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.577-583
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• 2022

In this study, the characteristics of self-healing mortars produced using an inorganic self-healing material consisting of ground granulated blast furnace slag, expansion agent, and anhydrite, were investigated. For three types of self-healing mortars with different amounts of the inorganic healing material, compressive strength was measured and the self-healing performance was evaluated through the constant water head permeability test. The healing rate and equivalent crack width according to crack-induced aging were used as indicies of healing performance evaluation. Considering the development of compressive strength of the self-healing mortars, the change in the healing rate with healing periods, and the economic feasibility, the optimal amount of inorganic self-healing materials was suggested as 20 % of the mass of cement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.765-773
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• 2018

The purpose of this study was to investigate the effect of Healing Beat on autonomic balance, heart rate, and anxiety in healthy adults exposed to stressors. Data were collected from 64 healthy volunteers who volunteered after responded to a recruitment announcement at D City University and analyzed using descriptive statistics, the X2-test, the t-test, and repeated measures of ANOVA. Results showed that both experimental and control general characteristics and variables were homogeneous. Significant intergroup differences were obtained for autonomic balance (F = 6.151, p <.001), heart rate (F = 5.455, p <.001), and anxiety (t = -7.633, p <.001). These results indicate Healing Beat is effective at relieving anxiety in stressful situations, and that Healing Beat can be used to relieve stress in many clinical situations or daily life when individuals are exposed to various stressors.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.397-404
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• 2021

In this study, it was reviewed that the effect of solid capsules on the quality of surface repair materials and the healing properties of long-term aging, as part of a study to utilize self-healing surface repair materials using solid capsules as repair materials. As a result of evaluation of the rheological properties of self-healing surface repair materials according to the mixing of solid capsules, plastic viscosity, yield stress, and table flow tended to decrease. In the case of compressive strength, 1MPa per 1% of the solid capsule decreased proportionally. As a result of evaluating the long-term healing properties, when 10% of solid capsules were mixed, a healing rate of 90% was shown at 28 days of healing, because the solid capsule was preserved even after 91 days of age had elapsed. after 91 days of healing, even in the case of 5% of solid capsules, a healing rate of 90% was shown.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.253-254
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• 2022

In this study, as part of a study to improve the self-healing performance of concrete, the fluidity and strength characteristics of mortar mixed into cement composites were compared and analyzed by controlling the mixing rate of BSC(Bioinspired Self-Healing capsule)

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.134-142
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• 2020

In this study, in order to evaluate the self-healing performance of cement composites the self-healing test method and the analysis method were suggested by applying constant water head permeability test, chloride migration test and repeated bending test. The method of making a cracked specimen and controlling crack width are also proposed. Constant head water permeability test can evaluate the healing performance by using the decreasing rate of water flow passing through the crack zone of a specimen. Furthermore, the equivalent crack width can be used to intuitively investigate the healing effect with healing period. The chloride migration test can evaluate the healing rate by the decreasing rate of the diffusion coefficient obtained by ASTM C 1202. Mechanical healing performance can be evaluated using ISR and IDR estimated from load vs. CMOD relationship graph obtained through the repeated bending test. Finally, the applicability of proposed self-healing evaluation methods was examined by testing mortar specimens with or without self-healing agents.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.4
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• pp.348-351
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• 2006

Purpose The purpose of this study was to evaluate the success rate of dental implant on post-traumatic region to rehabilitate missing teeth. Patients and Methods 5 patients who had been treated due to maxillofacial trauma during 2000 to 2004 at samsung medical center were selected for this study. 22 dental implants were installed to them for restoring missing teeth. The success rate of these dental implants was evaluated with criteria by T. Albrektsson. We divided installed 22 implants into 2 categories. One category consisted rough surface implants group and smooth surface implants group. And the other category consisted more healing group and less healing group. The healing time was calculated from point of trauma. Results The success rate of dental implants is 68.2% that is lower than other studies because of poor vascularity of bone bed and mechanical stress according to trauma. Rough surface implants group and More healing group showed superior success rate to others. (P < 0.05). Conclusion We found that to increase success rate, it may need rough surface implants and longer healing period.