PURPOSE: Fabrication of zirconia restorations with ideal mechanical properties in a short period is a great challenge for clinicians. The purpose of the study was to investigate the effect of heating rate on the mechanical and microstructural properties of monolithic zirconia. MATERIALS AND METHODS: Forty monolithic zirconia specimens were prepared from presintered monolithic zirconia blanks. All specimens were then assigned to 4 groups according to heating rate as Control, Group 15℃, Group 20℃, and Group 40℃. All groups were sintered according to heating rates with the sintering temperature of 1500℃, a holding time of 90 minutes and natural cooling. The phase composition was examined by XRD analysis, three-point bending test was conducted to examine the flexural strength, and Weibull analysis was conducted to determine weibull modulus and characteristic strength. Average grain sizes were determined by SEM analysis. One-way ANOVA test was performed at a significance level of 0.05. RESULTS: Only tetragonal phase characteristic peaks were determined on the surface of analyzed specimens. Differences among the average grain sizes of the groups were not statistically significant. The results of the three-point bending test revealed no significant differences among the flexural strength of the groups (P>.05). Weibull modulus of groups was ranging from 3.50 to 4.74. The highest and the lowest characteristic strength values were obtained in Group 20℃ and Control Group, respectively. CONCLUSION: Heating rate has no significant effect on the flexural strength of monolithic zirconia. Monolithic zirconia restorations can be produced in shorter sintering periods without affecting the flexural strength by modifying the heating rate.
Heating ; Hot Temperature

To evaluate the temperature distribution according to the size of the electrode and the thickness of the phantom using 8MHz radiofrequency capacitive heating device, various sized electrodes and phantoms were used in combination. The radii of the electrodes are 10, 15, 20, 25, 30 and 35cm. When the thickness of the phantom was 25cm or 30cm, homogenous heating was achieved by using the electrode which diameter was equal to or greater than the thickness of the phantom. When the thickness of the phantom was 20cm or less. Homogenous heating was not achieved by the larger diameter of the electorode. When the sizes of paired electrodes were not equal, the smaller electrode side was preferentially heated.
Electrodes ; Fever* ; Heating ; Hot Temperature

The purpose of this study was to investigate setting and thermal expansion of dental soldering investments. In order to compare expansion rates and to investigate the effect of water/powder ratio on expansion, setting and thermal expansion of four dental soldering investments were measured under three different water/powder ratio conditions: standard, 20% decreased and 20% increased. Setting expansion of investments was measured by use of dialgauge method. Each measurement was started two minutes later from the beginning of spatulation and recorded every one minute for one hour. Thermal expansion of cylindrical test specimens, 10mm diameter, 50mm length, was recorded in a Thermodilatometer at heating rate of 10degrees C per minute from 25degrees C to 700degrees C. The results of this study were obtained as follows: 1. Setting expansion rates under the standard water/power ratio condition were 0.198% in Speed-E, 0.090% in Deguvest, 0.080% in CM and Hi-temp. Setting expansion of Speed-E was significantly different from those of CM, Deguvest and Hi-temp, and setting expansion of Deguvest was significantly different from those of CM and Hi-temp(p<.05). 2. Under the decreased water/powder ratio condition, there was significant increase in setting expansion of 4 dental soldering investments(p<.05). 3. There were no significant differences in setting expansions of investments except Hi-temp between standard and increased water/powder ratio condition(p<.05). 4. Thermal expansion rates under the standard water/powder ratio condition were 1.923% in Deguvest, 1.629% in Speed-E, 1.619% in Hi-temp and 1.580% in CM. No significant difference in thermal expansions under the standard water/powder ratio condition existed only between Speed-E and Hi-temp(p<.05). 5. Under the decreased water/powder ratio condition, there was significant increase in thermal expansion of CM and Deguvest but decrease in thermal expansion of Speed-E(p<.05). 6. Under the increased water/powder ratio condition, there was significant decrease in thermal expansion of CM, Deguvest and Speed-E but decrease in thermal expansion of Hi-temp(p<.05).
Dental Soldering* ; Heating ; Hot Temperature ; Investments*

The renewed interest in the use of hyperthermia in cancer therapy is based on radiobiological And clinical evidence indicating that there may be significant thereapeutic advantages with the use of hyperthermia alone or combined with irradiation plus heat. Authors performed the experiment using the chemically induced mammary carcinoma of rats to observe the difference in temperature changes between tumor and normal tissue during heat, and to compare the response of the tumors to radiation alone and to radiation plus hyperthermia. The results were as follows 1. Temperature of tumors was significantly higher than in the normal tissue during heating and the difference was about 1.5degree C. 2. TCD50 in radiation alone and hyperthermia immediately following radiation was 1,282 rad and 795 rad, respectively and TER value was 1.81.
Animals ; Fever* ; Heating ; Hot Temperature ; Rats*

BACKGROUND: Currently available warming devices are often heavy and cumbersome, requiring development of more portable, user friendly, high efficiency fluid and blood warmer. The intravenous fluid heating capabilities of a new, heat-plate print circuit board (PCB) based warmer at various low flow rates were tested. METHODS: Model Joyother BM-1(R) was investigated for normal saline (0.9% NaCl) and colloid at various infusion rates (60-6000 ml/hr). Final temperatures were measured by electronic thermometer after passing through the warmer. Effective warming was defined as a fluid temperature > or = 32degrees C. Ambient temperature was maintained at 22-25degrees C. Degree of heating capability and temperature decrease were compared and correlated between different flow rates. RESULTS: The device warmed the room temperature crystalloid and colloid efficiently. Its warming capability was continuously improved as the flow rates increased in all tested flow rates, reaching maximum 41degrees C. After the warming, the temperature decrease showed high negative correlation with the flow rates. The extent of cooling was less in colloid. No overheating was noted at sudden brake. CONCLUSIONS: Joyother BM-1(R) heated crystalloid and colloid sufficiently and safely enough for clinical application (exit temperature > or = 35degrees C) at various flow rates. The warming capacity and the length of the intravenous tube infusion system determined the efficiency of the warmer. Further study is warranted for the efficiency of warming for the blood and its element changes.
Colloids ; Heating ; Hot Temperature ; Hypothermia ; Thermometers

The purpose of this study was to develop and test the validity of standardized Korean nomenclature of the International Classification for Nursing Practice (ICNP), developed by the International Council of Nursing (ICN). The four phases of the study were: (1) Two professors and 15 graduate students translated who were taking a nursing intervention course, translated nursing phenomena and nursing action of the ICNP into Korean; (2) 12 nurses with various clinical backgrounds reviewed the nomenclature taking into consideration of the definition, and contents for each Korean nursing terminology, and the Delphi method was used to determine the best appropriate nomenclature for each terminology; (3) 20 academic and clinical experts in nursing were given a questionnaire to rate the validity of each Korean nomenclature using a 5 point Likert scale ranging from very inappropriate to very appropriate; (4) five members of the Korean Nurses Association Research Committee reviewed the survey results and determined the most appropriate Korean nomenclature for each nursing phenomena and activity of the ICNP. Most nomenclature of the ICNP had a score of more than 4.0, but four nursing phenomena had a score between 3.5 and 4.0: Unilateral neglect(3.86), Care Giver strain (3.86), Health denial(3.86), Health Adjustment (3.86) and draining(2.63) . In nursing activity 726 items, except for twelve items, had a score of over 4.0: Drainage(2.63) Weaning(3.13), Caring(3.75), Cold Wrapping(3.63), distraction Technique(3.57), drawing(3.88), Establishing Report with(3.5), Heating Wrapping(3.5), Manipulating(3.75), Performing(3.88), Reading material(3.75) and Restricting(3.75).
Caregivers ; Classification ; Heating ; Hot Temperature ; Humans ; Nursing

In capacitive heating device, which considered efficient for deep heating, parallel arrangement of the electrodes is a serious limiting factor in heating for eccentrically located lesions because it causes overheating of the exposed ipsilateral skin surface, the heating pattern is also frequently inappropriate, arid the arrangement tends to be unstable due to the patient's gravity. Therefore we attempted an angular arrangement of the electordes to achieve more homogenous and efficient heating for such lesions. In phantom study, both the thermal profile and thermogram established the heating pattern in this unusual angular arrangement of the electrodes at 60degree, 90degree and 120degree angles, respectively. An angular arrangement was also clinically applied to 3 patients. The patients' tolerance was good without significant complication and the thermal distribution was satisfactory. In conclusion, this unusual arrangement of electrodes appears to be promising in the clinical application to the eccentrically located lesions.
Electrodes* ; Gravitation ; Heating* ; Hot Temperature* ; Humans ; Skin

The purpose of this study is to evaluate the flow ability of the thermoplasticized Gutta Percha in different temperatures. Four Gutta Percha products were classified by its hardness (soft, medium, and hard) and were experimented by the Rheometer (Melt flow indexer MFI-10, DAVENPORT, England) measuring apparatus, in (23 ± 2) ℃, and in a relative humidity of (50 ± 5) %, following the guidelines of ISO 1133-1:2011. The heating temperature ranged from 108℃, 160℃ to 200℃, and the load at 2.16 kg and 3.8 kg. The Gutta Percha was cut in 5 mm to be suitable for the rheometer pressurization process. After the experiment was conducted with a preheating time of 5 minutes, a cutting time of 5–240 seconds, and a sample of 10 grams, the Gutta Percha did not show any changes in fluidity for 108℃, 160℃, but showed a change in its flow ability in 200℃. Also, the Gutta Percha did not show any changes in its fluidity when it was pressurized by 2.16 and 3.8 kilograms. Therefore, this experiment shows that the heating temperature and the cut-off time showed a significance while measuring the melt flow rate.
Gutta-Percha ; Hardness ; Heating ; Hot Temperature ; Humidity

To make up for the shortcomings of traditional mild moxibustion, according to the principle and technical operation characteristics of traditional mild moxibustion, combined with temperature control technology, a novel infrared mild moxibustion device is developed, which is capable of real-time accurate temperature control. This novel infrares mild moxibustion device is composed of a host computer and an infrared radiation head. The host computer includes four modules: power supply, human-computer interaction interface, micro control unit (MCU) and drive circuit. The infrared radiation head mainly includes an infrared heater and a temperature sensor. This novel infrared mild moxibustion device is easy to operate. The electrothermal heating tablet can generate infrared radiation of 3 000-13 000 nm. After the temperature of the infrared heater is stabilized, the range of temperature change is ±0.50 ℃, realizing the goal of precise temperature control. In addition, it can operate moxibustion treatment at multiple acupoints at the same time, which is conducive to the dose-effect evaluation of mild moxibustion.
Humans ; Moxibustion ; Acupuncture Points ; Temperature ; Heating

In view of the limitations of the high operational difficulty, safety hazards and adverse reactions of traditional fire needle, and unclear treatment parameters of existing electric fire needles, a new digital electric fire needle instrument was designed and developed in this study. This instrument is a gun type structure, consisting of a gun body, a power supply interface on the gun body, a display unit and a drive unit, a heating unit, a cooling unit, a positioning unit, and a needle inserting unit in the gun body. This instrument can digitally realize the regulation of parameters such as fire needle inserting temperature, depth and speed, and it has the advantageous features of intelligent needle burning, precise positioning, and safe and easy operation. This instrument meets the needs of more patients, medical professionals and scientific researchers, and is conducive to promoting the development of fire needle acupuncture therapy.
Humans ; Needles ; Heating ; Research Personnel ; Temperature