The effect of guided flapless implant procedure on heat generation from implant drilling / 대한치과보철학회지

PURPOSE: The aim of this study was to evaluate the heat generation in bone in vitro during the guided flapless drilling procedure and the effect of drilling methods on the heat generation. MATERIALS AND METHODS: A model that has missing the first and second mandibular molars bilaterally was used. In group A, classical flap implant surgery was performed. In group B, flapless implant surgery using surgical guide was performed. In group C, flapless implant surgery using surgical guide without up-and-down pumping motion was performed. Temperature was measured with k-type thermocouple and a real-time digital thermometer. The thermocouples were placed at 0.5 mm away from the osteotomy area at the depths of 3 mm and 6 mm. The measured values were evaluated with independent t-test. RESULTS: The mean temperature generated was 27.2degrees C (SD +/- 2.1degrees C) and 27.5degrees C (SD +/- 2.3degrees C) for groups A and B, respectively. These differences were not statistically significant. In group C, the mean temperature was 37.0degrees C (SD +/- 3.4degrees C). There were statistically significant differences between groups B and C with respect to the mean temperature. CONCLUSION: These findings suggest that guided flapless drilling with up-and-down pumping motion may not significantly increase the bone temperature.

The Pre-test for Development of Insole which Maintains Constant Temperature in Shoe

OBJECTIVE: To investigate the change in plantar skin temperature in normal subjects wearing five different kinds of insoles. METHOD: Twenty normal subjects were chosen and were made to walk on a treadmill for five 30-minute sessions wearing the same shoes, and wearing five different kinds of insoles (four types were endothermic insoles, but one type was a normal insole) respectively. Subjects sat on a chair for 10 minutes before and after walking. The plantar skin temperature was recorded on 4 sites (from channel 1 to 4) on each left insole. The plantar skin temperature was recorded every 10 seconds for a total of 50 minutes, with T-type Thermocouple(R). RESULTS: There were no statistical differences in the change of plantar skin temperature for each insole before, during and after walking. No statistical differences in subjective thermal sense and Borg Rating on perceived exertion scale for each insole before, during and after walking. Time in peak plantar temperature was 25.9~28.3 minutes (after subjects starts walking), wearing normal insole. CONCLUSION: There was no statistical difference in the change of plantar skin temperature for the five different kinds of insoles However, we found this method to be effective in examining plantar skin temperature during walking.

Analysis of temperature rise on the surface of buchanan plugger using thermocouple / 대한치과보존학회지

This study was performed to evaluate the actual temperature rise on the surface of Buchanan plugger using thermocouple. The heat carrier system 'System B Heatsource' (Model 1005, Analytic Technologies, Redmond, WA, USA) and the Buchanan pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200degrees C on digital display and the power level on it was set to 10. Five thermocouples were placed in direct contact with the surface of each size of Buchanan's pluggers at 1 mm increments from the tip to the 4 mm length of shank. The heat control spring was touched for 5 seconds, and the temperature rise on the surface of the pluggers were measured at 1 sec intervals for more than 5 seconds with an accuracy of 0.01 using Data Logger. The data were statistically analyzed by one-way ANOVA. The results were as follows. 1. The position at which the temperature peaked was approximately at 1~2 mm far from the tip of Buchanan plugger (p<0.01). 2. The peak temperature was 215.25+/-2.28degrees C in F plugger, 185.94+/-2.19degrees C in FM plugger, 169.51+/-9.12degrees C in M plugger, and 160.79+/-1.27degrees C in ML plugger and the peak temperature was highest in F plugger and followed by, in descending order, FM plugger, M plugger. ML plugger showed the lowest peak temperature (p<0.01). 3. The temperature on the pluggers was decreased with the increase of touching time. This results suggest that the actual temperature on the surface of the pluggers does not correlate well with the temperature set on digital display. Heat concentrates around the tip. The larger plugger reveals lower temperature rise relatively.

Analysis of temperature rise on the root surface during continuous wave of condensation technique / 대한치과보존학회지

This study was conducted to evaluate the temperature rise on the root surface while the root canal is being obturated using continuous wave of condensation technique. Maxillary central incisor was prepared for repeated canal obturation. Ten thermocouples (Omega Engineering Inc., Stanford, USA) were placed at 1 mm increment from the anatomical root apex. The real temperature of Buchanan plugger was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan and the root surface temperature was recorded during obturation at 150degrees C, 200degrees C, 250degrees C and 300degrees C temperature settings of System B HeatSource (Model 1005, Analytic technologies, Redmond, WA, USA). After completion of the temperature recording, the dentinal-cementum thickness at each sites was measured. The data were analyzed using one-way ANOVA followed by Scheffe' s test and linear regression test. The results were as follows. 1. When the temperature was set at 150degrees C, 200degrees C, 250degrees C and 300degrees C on the digital display of System B HeatSource, the real temperature of the plugger at the 1mm point from the tip revealed 130.82+/-2.96degrees C, 158.00+/-5.26degrees C, 215.92+/-6.91degrees C and 249.88+/-3.65degrees C respectively. 2. The position of 8 mm from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.01). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was 2.37+/-0.09degrees C at 150degrees C setting, 3.11+/-0.12degrees C at 200degrees C setting, 3.93+/-0.09degrees C at 250degrees C setting and 5.69+/-0.15degrees C at 300degrees C setting respectively. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at 150degrees C, 200degrees C, 250degrees C and 300degrees C temperature settings on digital temperature display of System B HeatSource.

A Study On The Temperature Changes Of Bone Tissues During Implant Site Preparation / 대한치과보철학회지

The purpose of this study is to examine the possibility of thermal injury to bone tissues during an implant site preparation under the same condition as a typical clinical practice of Branemark implant system.All the burs for Branemark implant system were studied except the round bur.The experiments involved 880 drilling cases:50 cases for each of the 5 steps of NP, 5 steps of RP,and 7 steps of WP,all including srew tap,and 30 cases of 2mm twist drill. For precision drilling,a precision handpiece restraining system was developed(Eungyong Machinery Co.,Korea).The system kept the drill parallel to the drilling path and allowed horizontal adjustment of the drill with as little as 1 mu m increment.The thermocouple insertion hole.that is 0.9mm in diameter and 8mm in depth,was prepared 0.2mm away from the tapping bur,the last drilling step.The temperatures due to countersink,pilot drill,and other drills were measured at the surface of the bone,at the depths of 4mm and 8mm respectively. Countersink drilling temperature was measured by attaching the tip of a thermocouple at the rim of the countersink.To assure temperature measurement at the desired depths,''bent-thermocouples'' with their tips of 4 and 8mm bent at 120 were used.The profiles of temperature variation were recorded continuously at one second interval using a thermometer with memory function (Fluke Co.,U.S.A.)and 0.7mm thermocouples (Omega Co.,U.S.A.). To simulate typical clinical conditions,35mm square samples of bovine scapular bone were utilized.The samples were approximately 20mm thick with the cortical thickness on the drilling side ranging from 1 to 2mm.A sample was placed in a container of saline solution so that its lower half is submerged into the solution and the upper half exposed to the room air,which averaged 24.9 degrees C.The temperature of the saline solution was maintained at 36.5 degrees C using an electric heater (J.O Tech Co.,Korea).This experimental condition was similar to that ofa patient's opened mouth. The study revealed that a 2mm twist drill required greatest attention.As a guide drill, a twist drill is required to bore through a '' virgin bone,''rather than merely enlarging an already drilled hole as is the case with other drills.This typically generates greater amount of heat.Furthermore,one tends to apply a greater pressure to overcome drilling difficulty, thus producing even greater amount heat. 150 experiments were conducted for 2mm twist drill.For 140 cases,drill pressure of 750g was sufficient,and 10 cases required additional 500 or 100g of drilling pressure.In case of the former,3 of the 140 cases produced the temperature greater than 47 degrees C,the threshold temperature of degeneration of bone tissue (1983.Eriksson et al.5))which is also the reference temperature in this study.In each of the 10 cases requiring extra pressure,the temperature exceeded the reference temperature.More significantly,a surge of heat was observed in each of these cases.This observations led to addtional 20 drilling experiments on dense bones.For 10 of these cases,the pressure of 1,250g was applied.For the other 10,1,750g were applied.In each of these cases,it was also observed that the temperature rose abruptly far above the thresh-old temperature of 47 degrees C,sometimes even to 70 or 80 degrees C.It was also observed that the increased drilling pressure influenced the shortening of drilling time more than the rise of drilling temperature.This suggests the desirability of clinically reconsidering application of extra pressures to prevent possible injury to bone tissues. An analysis of these two extra pressure groups of 1,250g and 1,750g revealed that the t-statistics for reduced amount of drilling time due to extra pressure and increased peak temperature due to the same were 10.80 and 2.08 respectively suggesting that drilling time was more influenced than temperature. All the subsequent drillings after the drilling with a 2mm twist drill did not produce excessive heat, i.e.the heat generation is at the same or below the body temperature level. Some of screw tap,pilot,and countersink showed negative correlation coefficients between the generated heat and the drilling time,indicating the more the drilling time,the lower the temperature. The study also revealed that the drilling time was increased as a function of frequency of the use of the drill.Under the drilling pressure of 750g, it was revealed that the drilling time for an old twist drill that has already drilled 40 times was 4.5 times longer than a new drill. The measurement was taken for the first 10 drilings of a new drill and 10 drillings of an old drill that has already been used for 40 drillings. ''Test Statistics''of small samples t-test was 3.49,confirming that the used twist drills require longer drilling time than new ones.On the other hand,it was revealed that there was no significant difference in drilling temperature between the new drill and the old twist drill. Finally,the following conclusions were reached from this study: 1.Used drilling bur causes almost no change in drilling temperature but increase in drilling time through 50 drillings under the manufacturer-recommended cooling conditions and the drilling pressure of 750g. 2.The heat that is generated through drilling mattered only in the case of 2mm twist drills,the first drill to be used in bone drilling process;for all the other drills there is no significant problem. 3.If the drilling pressure is increased when a 2mm twist drill reaches a dense bone, the temperature rises abruptly even under the manufacturer-recommended cooling conditions. 4.Drilling heat was the highest at the final moment of the drilling process.

Development of a Device Equipped with a Thermocouple for Measuring Nasal Airflow

BACKGROUND AND OBJECTIVES: To measure nasal cavity function as an airway, rhinomanometry and acoustic rhinometry are currently being used in clinical settings. However, these methods are not helpful for continuously measuring the aerodynamic status of both nasal cavities simultaneously. Therefore, a new instrument to evaluate the nasal flow is required. MATERIALS AND METHODS: To measure the airflow of bilateral nasal cavity simultaneously, two thermocouples are held in the headset, with the tips of thermocouples positioned below nostrils. The thermocouples are connected to the analog-digital converter and the digitized data is transferred to a notebook computer, in which a graphical programming language software is installed. Eighteen adults were recruited for this study who had no structural abnormality in their nasal cavities. For every subject, measurements from acoustic rhinometry, the thermocouple device, and rhinomanometry were taken in succession. The data from the thermocouple device was compared with those taken from the acoustic rhinometry and rhinomanometry. RESULTS: A negative correlation was noted between the minimum cross-sectional area by acoustic rhinometry and the inspiratory slope by thermocouple. No correlation was noted between the results for rhinomanometry and the thermocouple device. CONCLUSION: The thermocouple device has some advantages over other devices for its non-invasive, continuous, and real-time measurements and its ability to measure bilateral nasal cavity simultaneously.

Percutaneous Cordotomy Using Thermocouple Electrodes / 대한마취과학회지

Effective noninvasive modalities such as radiotherapy and pharmacologic treatments have become highly developed in the treatment of intractable cancer pain. Although epidural narcotics have been considered particularly useful, limitations still remain in their effectiveness for some patients. Surgical therapy can be a useful alternative to these treatments. Cordotomy is one of the most effective surgical treatments. The first percutaneous cordotomy was attempted by Mullan and his associates in 1963. Rosomoff and his associates modified the procedure using radiofrequency two years later. Cordotomy was widely used by the late 1960's but due to its limited effectiveness and serious complications it was abandoned until 1980 when a new electrode was developed by Levin. A thermocouple cordotomy electrode such as the Levin electrode allows monitoring of impedance and tissue temperature. A radiofrequency lesion can be made by increasing the current directly to the desired temperature rather than by gradual heating with the usual incremental increases in lesion current and time. With the use of this electrode, consistent clinical effects are assured and operating time is reduced. The chances of boiling or charring are also minimized. Since this electrode was developed, cordotomy has received renewed attention virtually everywhere except in Korea. Five terminal cancer patients in whom conservative treatments had failed were treated by cordotomy using the three types of thermocouple electrodes: the levin cordotomy electrode; the TCE thermocouple electrode, and the Kanpolat CT electrode. Due to the small number of patients, a comparison of the effectiveness of these three types could not be made. Although complete pain relief was not achieved in every case, dosages of narcotics could be reduced as a result of this procedure. There were no serious complications except a transient paralysis of the ipsilateral arm in one case and headaches in four cases.

The Design of the control system of radiating therapeutic instrument / 医疗卫生装备

The control system of radiating therapeutic instrument, powerful and reliable, is designed with the new chips of P89LPC669 and MAX669. Its hardware organization, system function and software framework are introduced in this paper.