• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.339-349
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• 1999

The dental structure substituted by restorative materials may produce discomfort resulting from hot or cold stimuli. To investigate the effects of this stimuli on the human teeth, thermal analysis was carried out by calculation of general heat conduction equation in a modeled tooth using numerical method. The method has been applied to axisymmetric and two-dimensional model, analyzing the effects of constant temperature $4^{\circ}C\;and\;60^{\circ}C$. That thermal shock was provided for 2 seconds and 4 seconds, respectively and recovered to normal condition of $20^{\circ}C$ until 10 seconds. The thermal behavior of tooth covered with a crown of gold or stainless steel was compared with that of tooth without crown. At the same time, the effects of restorative materials(amalgam, gold and zinc oxide-eugenol(ZOE)) on the temperature of PDJ(pulpo-dentinal junction) has been studied. The geometry used for thermal analysis so far has been limited to two-dimensional as well as axisymmetric tooth models. But the general restorative tooth forms a cross shaped cavity which is no longer two-dimensional and axisymmetric. Therefore, in this study, the three-dimensional model was developed to investigate the effect of shape and size of cavity. This three-dimensional model might be used for further research to investigate the effects of restorative materials and cavity design on the thermal behavior of the real shaped tooth. The results were as follows; 1. When cold temperature of $4^{\circ}C$ was applied to the surface of the restored teeth with amalgam for 2 seconds and recovered to ambient temperature of $20^{\circ}C$, the PDJ temperature decreased rapidly to $29^{\circ}C$ until 3 seconds and reached to $25^{\circ}C$ after 9 seconds. This temperature decreased rather slowly with stainless steel crown, but kept similar temperature within $1^{\circ}C$ differences. Using the gold as a restorative material, the PDJ temperature decreased very fast due to the high thermal conductivity and reached near to $25^{\circ}C$ but the temperature after 9 seconds was similar to that in the teeth without crown. The effects of coldness could be attenuated with the ZOE situated under the cavity. The low thermal conductivity caused a delay in temperature decrease and keeps $4^{\circ}C$ higher than the temperature of other conditions after 9 seconds. 2. The elapse time of cold stimuli was increased also until 4 seconds and recovered to $20^{\circ}C$ after 4 seconds to 9 seconds. The temperature after 9 seconds was about $2-3^{\circ}C$ lower than the temperature of 2 seconds stimuli, but in case of gold restoration, the high thermal conductivity of gold caused the minimum temperature of $21^{\circ}C$ after 5 seconds and got warm to $23^{\circ}C$ after 9 seconds. 3. The effects of hot stimuli was also investigated with the temperature of $60^{\circ}C$. For 2 seconds stimuli, the temperature increased to $40^{\circ}C$ from the initial temperature of $35^{\circ}C$ after 3 seconds of stimuli and decreased to $30^{\circ}C$ after 9 seconds in the teeth without crown. This temperature was sensitive to surface temperature in the teeth with gold restoration. It increased rapidly to $41^{\circ}C$ from the initial temperature of $35^{\circ}C$ after 2 seconds and decreased to $28^{\circ}C$ after 9 seconds, which showed $13^{\circ}C$ temperature variations for 9 seconds upon the surface temperature. This temperature variations were only in the range of $5^{\circ}C$ by using ZOE in the bottom of cavity and showed maximum temperature of $37^{\circ}C$ after 3 seconds of stimuli.

• YAKHAK HOEJI
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• v.59 no.2
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• pp.70-76
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• 2015

A Softgel is an oral dosage form for medicine similar to capsules and softgel dosage form offers several advantages over other oral dosage forms, such as delivering a liquid matrix designed to solubilize and improve the oral bioavailability of a poorly soluble compound as a unit dose solid dosage form, delivering low and ultra-low doses of a compound. This study aimed to qualify a proprietary vegetable soft capsule which contains modified starch and carrageenan as capsule shell components compare to the conventional gelatin softgel. Four kinds of samples were prepared with vegetable and gelatin capsule shell, respectively. Morphology of capsule shell, mechanical strength of capsule, and hygroscopic properties were studied for comparing the quality attributes of softgel. Short-term stability against heat and moisture was also investigated in this study. Vegetable capsule shell showed better mechanical strength, physical stability and disintegration time for temperature and humidity than those of conventional gelatin capsule shell with four different filling materials used frequently as soft capsule form. Conclusively, this vegetable capsule shell polymer system can replace easily gelatin-shell systems and additionally allows encapsulation of lipid fills at high temperatures that are semisolid or solid-like at room temperature.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.365-376
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• 1999

The importance of finishing and polishing the restoration has been described by several authors. The final step provides for improved metallurgical properties, better marginal adaptation, reduced plaque accumulation. Unfortunately, finishing of the restorations can produce damage from temperature rises at the pulpal wall. The aim of this study was to determine the changes in temperature can be occurred during the use of finishing and polishing instruments under a variety of conditions. ; with or without a water coolant, intermittent or continuous operation, high or low rotation speed, remaining dentin thickness and various restorative materials. Class V preparations were cut on extracted molars and restored with composite resin(Z 100), resin-modified glass ionomer cements(Dyract, Fuji II LC), and amalgam. Finishing was done with aluminum oxide coated disc($Sof-lex^{(R)}$ polishing disc, 3M, USA). The following results were obtained. 1. The rise of temperature during polishing of amalgam restorations was the highest among the all experimental groups except polishing with water coolant(P<0.05). However, there were no statistical differences in temperature rises between Z 100, Dyract and Fuji II LC(P>0.05). 2. The intrapulpal temperature was greatly influenced by the applied time, and intermittent polishing was showed significantly lower temperature rises than continuous polishing(P<0.01). 3. The intrapulpal temperature was increased according to the application of polishing regard less of using water coolant. However, polishing with water coolant showed significantly lower temperature in the pulp than not used water coolant(P<0.01).

• Journal of Oral Medicine and Pain
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• v.26 no.3
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• pp.243-252
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• 2001

본 연구에서는 구강 내 공기 중 설태 제거 전후의 휘발성 황화합물 농도를 gas chromatography를 이용하여 비교 분석하였다. 피검자로는 서울대학교 치과병원 구취클리닉에 내원한 환자 중에서 치주 건강 상태가 양호하며 구취를 호소하는 환자 18 명(평균연령 31.4세; 남자 8명, 여자 10명)을 대상으로 하였으며 구취를 측정하기 전에 모든 피검자들은 실험 전날 취침 전부터 실험 당일 실험시작 전까지 음식 섭취나 양치질 등의 모든 구강 활동을 금지하였다. 구취 시료는 채취 전에 피검자로 하여금 3분간 입을 다물게 한 후 입을 약 2cm정도 벌린 상태에서 시행하였으며 시료 채취 후 설태를 제거하였다. 설태 제거 후에 구강 내 공기를 다시 채취한 후 gas chromatography를 통하여 휘발성 황화합물의 각 성분별 농도를 분석하였다. 분석과정에서는 과거에 휘발성 황화합물의 검출 시 사용되어진 sampling loop와 isothermal run condition 대신 좀더 효율적인 직접표본주입방법과 oven temperature programmed analysis를 시행하였다. 1. 전체 휘발성 황화합물은 Hydrogen sulfide (59.96%), Methyl mercaptan (25.08%), Dimethyl sulfide (14.96%)로 구성되었다. 이 중 Hydrogen sulfide는 전체 휘발성 황화합물중 약 60%를 차지하여 치주상태가 양호한 구취환자에서의 주요한 구취 구 성 성분이었다. 2. 설태 제거 후 전체 휘발성 황화합물의 농도감소는 제거 전에 비하여 41.71%로 유의 하게 감소하였다(p<0.01). 3. 설태 제거 후에 Hydrogen sulfide의 농도감소는 43.62% (p<0.01), Methyl mercaptan 의 농도감소는 38.88% (p<0.05), 그리고 Dimethyl sulfide의 농도감소는 30.21% (p<0.01)로 각각 유의하게 감소하였다. 4. 전체 휘발성 황화합물의 구성비율은 설태 제거 전후에 유의한 차이가 없었다 (p>0.05).

• The Korean Journal of Health Service Management
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• v.6 no.1
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• pp.15-25
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• 2012

The purpose of this study is to examine relations among the subjective oral symptoms, masticatory performance and life quality of aged people residing in some regions of a large city, ultimately providing basic information needed to develop and implement programs oral health project and oral health education programs for the oral health promotion of those people. For the above purpose, this researcher conducted a questionnaire survey of people aged 65 or over from July 14th to 30th, 2011. Among the copies of the questionnaire distributed to the subjects, 318 were recollected. Out the recollected forms, 18 which were deemed as in appropriately filled in were excluded, and the remaining 300 were finally analyzed. The results are as follows. Subjective oral symptoms and masticatory performance have correlation(p<0.001) with aged people's life quality. Factors of influencing life quality were indicated to be gender(p=0.046), age(p=0.008), appearance of living together(<0.001), masticatory performance(p<0.001), and temperature reaction(p=0.018). This study has limitation because of being information that was obtained just with questionnaire survey on subjective oral symptoms. It is considered that there is a need of surveying along with objective data on oral symptoms hereafter.

• Journal of Convergence for Information Technology
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• v.9 no.5
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• pp.190-200
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• 2019

This study aimed to investigate the associations between subjective oral health status and OHIP-14 among Chinese residents. A survey was conducted on the Chinese residing in Busan. As a result of analyses on the collected data with SPSS 25.0 the OHIP-14 was significantly different depending on the subjective oral health status including mastication discomfort experience, toothache experience, oral temperature sensitive response experience, gingival bleeding and disease experience, dry mouth experience and halitosis experience. The major variables were all positively correlated. Among the factors of subjective oral health status affecting the oral health-related quality of life, the influences of mastication (p<0.001) and halitosis (p<0.05) were significant. There is a need for a medical support system that can provide practically oral health policies and support Korean language for foreigners.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.153-154
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• 2002

Salmonella typhi Ty21a is an attenuated strain of S. typhimurium and used for oral typhoid vaccine. In an attempt to increase the stability of Ty21a manufacturing typhoid vaccine, the stability of freeze-dried Ty21a including additives at various temperature conditions was studied. In order to investigate the freeze-drying rate of Ty21a according to various absorbance, Ty21a was lyophilized by using 8% sucrose as a stabilizer. (omitted)

• Journal of Oral Medicine and Pain
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• v.7 no.1
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• pp.77-85
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• 1982

Identification of blood group from dental hard tissue for the purpose of individual identification of a highly burned corpse would play a significant role in a practical legal medicine. The author conducted a study of blood group with teeth left stading at a high temperature by the method of elution test. The following results were obtained. 1. The blood identifcation from heated dental hard tissue proved to be possible. 2. In cases of heat-treated theeth at $100^{\circ}C$ for 120 minutes, at $150^{\circ}C$ for 120 minutes and at $200^{\circ}C$ for 45 minutes for A.B.O(H) blood group, the identification of blood group was possible. 3. In case of heat-treated teeth, thermostability of blood group was found to be $150^{\circ}C$. 4. The adequate surface area for the detection of blood group was 40-80 meshes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.2
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• pp.109-115
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• 2015

Odontoma is the most common odontogenic benign tumor, and the treatment of choice is generally surgical removal. After excision, bone grafts may be necessary depending on the need for further treatment, or the size and location of the odontoma. Although the osteogenic capacity of a demineralized tooth was verified as early as 1967 by Urist and many other investigators, the cumbersome procedure, including a long demineralization time, may be less than comfortable for clinicians. A modified ultrasonic technology, with periodic negative pressure and temperature control, facilitated rapid and aseptic preparation of demineralized teeth for bone grafts. This approach reduces the demineralization time dramatically (${\leq}80$ minutes), so that the graft material can be prepared chairside on the same day as the extraction. The purpose of this article is to describe two cases of large compound odonotomas used as graft material prepared chairside for enucleation-induced bony defects. These two clinical cases showed favorable wound healing without complications, and good bony support for future dental implants or orthodontic treatment. Finally, this report will suggest the possibility of recycling the benign pathologic hard tissue as an alternative treatment option for conventional bone grafts in clinics.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.89-96
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• 1999

CJ-50002 is an oral vaccine against V.vulnificus infection composed of whole cell lysate of V. vulnificus. The general pharmacological properties of CJ-50002 were evaluated in various animals and in vitro system. CJ-50002 at oral doses of 0.2, 2 and 20 mg/kg had no effect on general behavior in mice, chromo- and electro-convulsions in mice, writhing syndrome induced by acetic acid in mice, body temperature in rats, charcoal meal propulsion in mice and urine and electrolytes excretion in rats. However, oral administration of CJ-50002 at dose of 20 mg/kg prolonged the hexobarbital-inuced sleeping inducing time in mice. In anesthetized dogs, CJ-50002 showed no effect on blood pressure, heart rate and ECG but decreased the respiratory rate and femoral blood flow at dose of 20 mg/kg. p.o. CJ-50002 had no effect on the contractile response of the isolated guinea pig ileum to various spasmogen at concentrations of 0.2, 2 and 20 $\mu\textrm{g}$/ml, respectively. Since these pharmacological effects of CJ-500o2 were observed at dose much greater than those in clinical use (approximately 0.16 mg/kg, p.o.), it is likely that this vaccine may be relatively free of undesirable effects in clinical practice.