• Conservation Science in Museum
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• v.27
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• pp.103-124
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• 2022

This study examined the properties of the materials used in the three-story pagoda at Jangha-ri, Buyeo. It was performed in order to identify the objective condition of the pagoda and establish an appropriate plan for the conservation treatment of the pagoda. According to the study, the average total magnetic susceptibility was 3.71 (10^-3 SI unit), and at least four types of granite with different origins were likely used in the production of the pagoda. The ultrasonic velocity averaged 1,519m/s, and the coefficient of weathering showed an average of grade 4. The thermal gradient between the cement (restoration materials) and original materials was identified through thermal imaging. In some areas, the cement restoration materials required replacement with new stone materials with properties similar to those of the original stone materials. Taking into account these results, a map of weathering damage was prepared and appropriate conservation treatment plans were established based on the findings of previous studies. Since the pagoda had suffered severe biological damage and discoloration, surface contaminants were removed through wet cleaning with distilled water and a brush. The exfoliated areas were reinforced on the site by mixing epoxy resin with powdered stone with the same properties as the original stone materials of the pagoda.

• The korean journal of orthodontics
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• v.35 no.4 s.111
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• pp.286-294
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• 2005

The purpose of this study was to evaluate the efficacy of an electric toothbrush, with a specially designed orthodontic brush head, compared to a manual toothbrush on the periodontal health of patients with fixed orthodontic appliances Forty patients were randomly divided into two groups. the electric and the manual toothbrush groups, 1 month after attachment of fixed orthodontic appliances. Periodontal status was measured using a plaque index, a gingival index. a bleeding index, a pocket depth and a relative attachment loss, at baseline and after 3 months. 6 months, 9 mouths. and 12 mouths. The Braun Oral-B Plak Control with Ortho OD 15-1 brush head was used as the electric toothbrush while the Butler G.U.M 124 was given as the manual toothbrush. In the manual toothbrush group, the giugival and bleeding indices showed no statistically significant differences, but the plaque index was significantly decreased (P<0.001) and pocket depth as well as relative attachment loss were significantly increased (p<0.01). In the electric toothbrush group. the bleeding index, pocket depth and relative attachment loss showed no statistically significant differences. but the plaque and gingival indices were significantly decreased (p<0.001). In the case of the plaque. giugival and bleeding indices, there were no statistically significant differences between the electric and the manual toothbrush groups. On the contrary, in the case of pocket depth and relative attachment loss, there were statistically significant differences between the electric and the manual toothbrush groups: an increase in the manual toothbrush groups unlike the electric toothbrush group which kept the same state (P<0.05) These findings suggest that an electric toothbrush is useful for orthodontic patients with fixed appliances.

• The korean journal of orthodontics
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• v.34 no.4 s.105
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• pp.363-370
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• 2004

Patients with fixed orthodontic appliances frequently have increased levels of plaque accumulation leading to the possibility of gingivitis or enamel decalcification. Although many methods may be helpful in reducing dental plaque formation, the optimal mechanical removal of plaque is the most important factor during orthodontic treatment. The purpose of this study was to evaluate the efficacy of an electric toothbrush (with a specially designed orthodontic brush head) compared to a manual toothbrush in controlling plaque and gingivitis for patients with fixed orthodontic appliances. Oral hygiene status was measured in thirty-four patients using a plaque index, a gingival index and a bleeding index, before and four weeks after the attachment of fixed orthodontic appliances. Patients were randomly divided into two groups: electric and manual toothbrush groups. Oral hygiene instruction was given according to the type of toothbrush used. The Braun Oral-B D9511 with Braun Oral-B Ortho OD 15-1 brush head was used as the electric toothbrush while the Butler G.U.M. 124 was given as the manual toothbrush. After four md eight weeks, oral hygiene status was measured again. Through a comparison between the electric and the manual toothbrush groups, the following results were obtained. 1. All oral hygiene indices showed an increasing tendency after four weeks of fixed orthodontic appliance. 2. All indices presented a decreasing tendency four and eight weeks after oral hygiene instruction. 3. In case of the gingival index and bleeding index, the decreasing tendency did not show a statistically significant difference between the electric and the manual toothbrush groups. 4. The decreasing tendency of plaque index presented a statistically significant difference between the two groups, showing that the electric toothbrush was more effective in terms of oral hygiene. These findings suggest that an electric toothbrush is useful to orthodontic patients with fixed appliances.