• Title/Summary/Keyword: Right to light

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Localization of Sensory Neurons Innervating the Rat Intestine Using the Cholera Toxin B Subunit(CTB) and Wheat Germ Agglutinin-Horseradish Peroxidase(WGA-HRP) (표지방식을 이용한 흰 쥐 복강 내장을 지배하는 감각신경세포체와 신경섬유의 표지부위)

  • Lee, Dong-Hyup;Lee, Chang-Hyun;Lee, Moo-Sam
    • Journal of Yeungnam Medical Science
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    • v.15 no.1
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    • pp.75-96
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    • 1998
  • The local arrangement of sensory nerve cell bodies and nerve fibers in the brain stem, spinal ganglia and nodose ganglia were observed following injection of cholera toxin B subunit(CTB) and wheat germ agglutinin-horseradish peroxidase(WGA-HRP) into the rat intestine. The tracers were injected in the stomach(anterior and posterior portion), duodenum, jejunum, ileum, cecum, ascending colon or descending colon. After survival times of 48-96 hours, the rats were perfused and their brain, spinal and nodose ganglia were frozen sectioned ($40{\mu}m$). These sectiones were stained by CTB immunohistochemical and HRP histochemical staining methods and observed by dark and light microscopy. The results were as follows: 1. WGA-HRP labeled afferent terminal fields in the brain stem were seen in the stomach and cecum, and CTB labeled afferent terminal fields in the brain stem were seen in all parts of the intestine. 2. Afferent terminal fields innervating the intestine were heavily labeled bilaterally gelalinous part of nucleus of tractus solitarius(gelNTS), dorsomedial part of gelNTS, commissural part of NTS(comNTS), medial part of NTS(medNTS), wall of the fourth ventricle, ventral border of area postrema and comNTS in midline dorsal to the central canal. 3. WGA-HRP labeled sensory neurons were observed bilaterally within the spinal ganglia, and labeled sensory neurons innervating the stomach were observed in spinal ganglia $T_2-L_1$ and the most numerous in spinal ganglia $T_{8-9}$. 4. Labeled sensory neurons innervating the duodenum were observed in spinal ganglia $T_6-L_2$ and labeled cell number were fewer than the other parts of the intestines. 5. Labeled sensory neurons innervating the jejunum were observed in spinal ganglia $T_6-L_2$ and the most numerous area in the spinal ganglia were $T_{12}$ in left and $T_{13}$ in right. 6. Labeled sensory neurons innervating the ileum were observed in spinal ganglia $T_6-L_2$ and the most numerous area in the spinal ganglia were $T_{11}$ in left and $L_1$ in right. 7. Labeled sensory neurons innervating the cecum were observed in spinal ganglia $T_7-L_2$ and the most numerous area in the spinal ganglia were $T_{11}$ in left and $T_{11-12}$ in right. 8. Labeled sensory neurons innervating the ascending colon were observed in spinal ganglia $T_7-L_2$ in left, and $T_9-L_4$ in right. The most numerous area in the spinal ganglia were $T_9$ in left and $T_{11}$ in right. 9. Labeled sensory neurons innervating the descending colon were observed in spinal ganglia $T_9-L_2$ in left, and $T_6-L_2$ in right. The most numerous area in the spinal ganglia were $T_{13}$ in left and $L_1$ in right. 10. WGA-HRP labeled sensory neurons were observed bilaterally within the nodose ganglia, and the most numerous labeled sensory neurons innervating the abdominal organs were observed in the stomach. 11. The number of labeled sensory neurons within the nodose ganglia innervating small and large intestines were fewer than that of labeled sensory neurons innervating stomach These results indicated that area of sensory neurons innervated all parts of intestines were bilaterally gelatinous part of nucleus tractus solitarius(gelNTS), dorsomedial part of gelNTS, commissural part of NTS (comNTS), medial part of NTS, wall of the fourth ventricle, ventral border of area postrema and com NTS in midline dorsal to the central canal within brain stem, spinal ganglia $T_2-L_4$ and nodose ganglia. Labeled sensory neurons innervating the intestines except the stomach were observed in spinal ganglia $T_6-L_4$. The most labeled sensory neurons from the small intestine to large intestine came from middle thoracic spinal ganglia to upper lumbar spinal ganglia.

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Time Course Variation of Vitamin $C_3$ Content in Leg Skin of Broiler Chicks Exposed to Different Dose of UVB Light (자외선의 상이한 선양을 조사한 브로일러 병아리의 다리 피부중 비타민 $C_3$ 함양의 경시적 변화)

  • 장윤환;김강수;여영수;강훈석;조인호;배은경
    • Korean Journal of Poultry Science
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    • v.20 no.2
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    • pp.93-105
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    • 1993
  • This study was carried out to determine the concentrations of previtamin D$_3$(PreD$_3$), lumisterol$_3$(L3), tachystero1$_3$(73), vitamin D$_3$(VD$_3$) and provitamin D$_3$(ProD$_3$) in leg skins of broiler chicks exposed to UVB lights (maximum intensity at 297 nm) with dose of 0.204 or 0.409 mJ/$\textrm{cm}^2$(30 or 60 min irradiation) . The broiler Hubbard line day old chicks(2 dose $\times$9 elapsed time $\times$4 replica+10 control=82) were fed VD-deficient diet for 31 days in a windowless subdued light room. The skin was collected at 0, 6, 12, 18, 30, 42, 66, 90 or 138 hr after UVB irradiation. The skin lipid was extracted by 9% ethyl acetate/n-hexane, and the fraction of VD$_3$ and its analogues was purified by Sep-Pak silica cartridge. The straight phase HPLC was utilized to analyze ProD$_3$ and its products. The mole %(absolute level expressed in ng/$\textrm{cm}^2$) of PreD$_3$ in leg skin (epidermis+dermis) was 4.67%(44 ng/$\textrm{cm}^2$) or 3.97%(37 ng/$\textrm{cm}^2$) right after UVB irradiation by 0.204 or 0.409 mJ/$\textrm{cm}^2$(30 or 60 min) at 15 cm distance, respectively. It content in leg skin at 0 hr after exposure was 7.24%(12 ng/$\textrm{cm}^2$) or 0.92%(9 ng/$\textrm{cm}^2$), respectively. The increase in irradiation dose did not affect proportionally the If synthesis.73 concentration in leg skin was 0.58%(S ng/$\textrm{cm}^2$) or 0.57%(6 ng/$\textrm{cm}^2$), respectively 0 hr after irradiation. The VD$_3$ in leg skin of birds exposed to UVB light with dose of 0.204 or 0.409 mJ/$\textrm{cm}^2$ was 2.13% (21 ng/$\textrm{cm}^2$) or 0.97% (16ng/$\textrm{cm}^2$), respectively at 0 hr after exposure, 2.72%(26ng/$\textrm{cm}^2$) or 3.84%(37ng/$\textrm{cm}^2$), respectively at 6 hr, and 4.30% ((33ng/$\textrm{cm}^2$) or 6.40%(76ng/$\textrm{cm}^2$), respectively at 12 hr. The peak concentration of VD$_3$ was presented at 18 or 30 hr when 0.204 or 0.409 mJ/$\textrm{cm}^2$) was treated, respectively. It was shown that 18~30 hr were necessary for the thermal conversion of PreD$_3$ into VD$_3$ in the leg skin of broiler chicks. The ProD$_3$ contents in leg skins of negative control, 0.204 mJ/$\textrm{cm}^2$ and 0.409 mJ/$\textrm{cm}^2$ treated birds were 966, 948 and 815 ng/$\textrm{cm}^2$, respectively at right before and after UVB exposure. It was estimated that 18 or 151 ng/$\textrm{cm}^2$ of ProD$_3$ was isomerized to PreD$_3$, L$_3$, T$_3$ and VD$_3$ when exposed to 0.204 or 0.409 mJ/$\textrm{cm}^2$, respective)y. Consequently it was shown that when double dose of UVB light was applied to irradiate the chick body, more but not double synthesis of VD$_3$ and its analogues was occured in leg skin of brolier chicks.

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The Change of Nurse호s Status According to the Status of Women II -From the post medieval epoche to late modern epoche- (여성의 지위에 따른 간호사의 위상 변화 II -중세 이후부터 근대 후기까지-)

  • 최순옥
    • Journal of Korean Academy of Nursing
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    • v.29 no.1
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    • pp.139-149
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    • 1999
  • It is very important to establish precisely the historical phases of nursing. We nurses should try to acquire the central social position in the health management system in the near the future, the 21st Century. Therefore my treatise aims to orient the desirable phases of the history of nursing through the feministic survey of the history of nursing from the post medieval epoche to the modern epoche. During the time of the renaissance which gave morning light to the modern epoche, the antique Athenian thinking of sex was again revived. Athenian excluded the women from the public and autonomous regions. All the medical activity, once dominated by the women, was misfortunately regarded as superstition acted by witches. Accordingly, the nursing women were to hunted as witches. In short, in the early modern epoche, women began to be excluded from the history of medical activities. In the middle modern epoche characterized by the enlightenment movement and early capital economic system, capitalistic patriarchal system began to be formed by change in the economic system. The status of women began to be greatly dropped below by the social distinction of the private dimension of home and the Public dimension of job. The woman was deprived of even the occasion to get the official license of medicine and medical institutions were handed to the state or the powerful and rich merchants. Accordingly, nursing acted mainly in the nunnery as the total approach to the patients was destructed wholly and transformed into the means of earning the money. Therefore unprepared low class -women began to engage in nursing only for the money. From then on, nursing activity was tunneled through the dark age for 200 years. In the late modern epoche characterized by the contrast of the accumulated vast capital by industrialization and vast poverty of the peoples, feminism began to float over the surface for the acquisition of equality of men and women from England. A feminist, Nightingale insisted that the women as nurses should be responsible for the healthy life of man. She tried the professional nursing education for women. Accordingly she not only contributed to the intellectual progress of women but also inspired in women the consciousness of the professional job. She tried to realize the ideal of at-that-time-feminists by engaging in nursing all through life. She really paved the road to contemporary nursing. In the near the future, I will write to describe how the late modern epoche nursing has fallen into the dilemma through the 1st and 2nd world wars and matured capitalism and to consider contemporary nursing with the status of women. All these papers aim to give proper recognition of nursing and right orientation of the future 21st Century nursing.

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The Effects of Wearing Roller Shoes on Muscle Activity in The Lower Extremity During Walking (롤러신발과 일반신발의 착용 후 보행 시 하지근의 근전도 비교)

  • Chae, Woen-Sik;Lim, Young-Tae;Lee, Min-Hyung;Kim, Jung-Ja;Kim, Youn-Joung;Jang, Jae-Ik;Park, Woen-Kyoon;Jin, Jae-Hong
    • Korean Journal of Applied Biomechanics
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    • v.16 no.3
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    • pp.137-148
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    • 2006
  • The purpose of this study was to compare muscle activity in the lower extremity during walking wearing jogging and roller shoes. Twelve male middle school students (age: 15.0 yrs, height 173.7 cm, weight 587.7 N) who have no known musculoskeletal disorders were recruited as the subjects. Seven pairs of surface electrodes (QEMG8, Laxtha Korea, gain = 1,000, input impedance >$1012{\Omega}$, CMMR >100 dB) were attached to the right-hand side of the body to monitor the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), and medial (GM) and lateral gastrocnemius (GL) while subjects walked wearing roller and jogging shoes in random order at a speed of 1.1 m/s. An event sync unit with a bright LED light was used to synchronize the video and EMG recordings. EMG data were filtered using a 10 Hz to 350 Hz Butterworth band-passdigital filter and further normalized to the respective maximum voluntary isometric contraction EMG levels. For each trial being analyzed, five critical instants and four phases were identified from the recording. Averaged IEMG and peak IEMG were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions (p<.05). The VM, TA, BF, and GM activities during the initial double limb stance and the initial single limb stance reduced significantly when going from jogging shoe to roller shoe condition. The decrease in EMG levels in those muscles indicated that the subjects locked the ankle and knee joints in an awkward fashion to compensate for the imbalance. Muscle activity in the GM for the roller shoe condition was significantly greater than the corresponding value for the jogging shoe condition during the terminal double limb stance and the terminal single limb stance. Because the subjects tried to keep their upper body weight in front of the hip to prevent falling backward, the GM activity for the roller shoe condition increased. It seems that there are differences in muscle activity between roller shoe and jogging shoe conditions. The differences in EMG pattern may be caused primarily by the altered position of ankle, knee, and center of mass throughout the walking cycle. Future studies should examine joint kinematics during walking with roller shoes.

A Study on the Temperature Change of Green House using Aerogel (에어로젤을 사용한 시설하우스의 온도 변화에 대한 연구)

  • Yang, Ji-Ung;Lee, Eun-Suk;Ko, Joon-Young;Kim, Won-Kyung;Byun, Jae-Young;Park, Jin-Gyu;Choi, Won-Sik
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.6_2
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    • pp.1067-1074
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    • 2020
  • Green houses provide a more conditioned and warmer environment than the outside environment due to insulation. Currently used insulation materials include soft film (PVC, PE, EVA), foamed PE sheet, non-woven fabric, reflective film, and multi-layer insulation curtain, but there are many disadvantages and to compensate for this, silica aerogel insulation material with excellent warmth, light weight, and small volume Research using is in progress. In this study, the temperature change of the quadruple-structure green house and the temperature change in the dual-structure green house of soft film and silica airgel were investigated. The daytime temperature change was highest in A and A2 (soft film) at 10 to 16:00 after sunrise, but showed the lowest temperature at 17 to 18:00, which is the sunset time, showing the greatest change. The airgels of D and D2 showed the smallest change in temperature after sunrise and right after sunset. That is, it can be said that the airgel is hardly affected by external temperature. The temperature change at night was highest in D and D2 (aerogel) for both quadruple and dual structures. The temperature at night was measured higher in the quadruple structure than in the double structure. As for the ratio of the internal temperature to the external temperature for the quadruple structure and the double structure, D (aerogel) was not affected by the external temperature during the day in the quadruple structure and the double structure. D (Aerogel) seems to be able to reduce the damage caused by high temperatures in summer due to the high thermal insulation effect of the airgel, as the temperature rises above 4℃ at night. And in winter, it helps to save heating costs due to less heat emitted to the outside.

The Meaning of Parenthood and Christian Educational Care (부모 됨의 의미와 기독교 교육적 돌봄)

  • Jeung-Gwan Lee
    • Journal of Christian Education in Korea
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    • v.72
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    • pp.49-70
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    • 2022
  • The purpose of this study is to suggest a response and solution through Christian educational care to the crisis and change of the era of low birth rate faced by Korean society and the Korean church. This study proposes to find an alternative to the biblical aspect of pregnancy, childbirth, and parenthood as God's blessing for the demographic cliff and low birth rate problem that have become a reality in Korean society and churches. Being a parent in an age of low birth rate is very difficult, but on the other hand, it gives happiness and joy. Being a parent is a blessing from God, and is the most important and valuable thing in life. However, modern society emphasizes the right and necessity to choose one's own parenthood status. In the nuclear family, the decrease in the number of children, and the development of child research, parents feel more responsibility and economic burden for raising children than ever before. Therefore, it is a reality that the number of people who delay becoming parents or voluntarily do not have children is gradually increasing. To improve the perception of becoming a parent due to a decrease in responsibility for raising children, it is necessary to shed light on marriage, pregnancy, childbirth, and childrearing from a Christian educational point of view. In addition, it is necessary to understand the recognition of being a parent and the characteristics of childbirth and rearing, and to analyze past and present value changes. This study will also discuss the causes of low birthrate and try to provide Christian educational care for childcare including solving the low birthrate problem.

A study on the oral health care of pregnant women in a region (일부지역 임산부의 구강건강관리에 대한 조사연구)

  • Lee, Ka-Yean;Won, Bok-Yeon
    • Journal of Korean society of Dental Hygiene
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    • v.9 no.1
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    • pp.1-14
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    • 2009
  • The purpose of this study was to examine the oral health care aware-ness of pregnant women and their actual oral health care in an effort to provide information on how to assist pregnant women to have the right knowledge on oral health and improve their oral health care. The subjects in this study were pregnant women who used obstetrics and gynecology hospitals or participated in pregnancy/child-rearing programs in the region of P. After a self-administered survey was conducted in July and August 2008, the following findings were given: 1. As for the best case of oral health care, the largest number(77.2%) of the pregnant women investigated brushed all the teeth, gums and tongue when they did toothbrushing. The smallest number of the women(6.8%) spent three minutes or more brushing their teeth. 2. As to dental treatment experience during pregnancy by age, 27.0 percent of the age 26-30 group had ever received dental treatment during pregnancy, which was higher than the rates of the other age groups with the same experience. 3. Regarding the necessity of oral health education geared toward pregnant women, 94.1 percent of the age 26-30 group and 96.3 percent of the group of age 31 and up felt the need for that, which were significantly higher than 72.7 percent of the age 20-25 group who agreed to the necessity of that education. 4. As to connections between oral health status and oral health care, the women who were in good oral health got 6.60 on oral health care. They scored significantly higher than those who were in a moderate state of oral health and who were in bad oral health, as the latter two groups respectively got 5. There was a significant correlation between oral health state and oral health care and between oral health knowledge and oral health care. The better oral health status led to better oral health knowledge, and the better oral health knowledge was followed by better oral health care. 6. As for factors affecting oral health care, oral health knowledge had the largest impact on that, followed by age, oral health status, experience of receiving oral health education for pregnant woman, dental treatment experience during pregnancy, monthly income and stress caused by oral diseases. Given the findings of the study, oral health education should be provided in light of the special physical and mental state of pregnant women. They should be encouraged to receive possible dental treatment during pregnancy if necessary, and they should learn about how to cope with a dental disease in case of develop it.

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Clinical Presentation and Frequency of Risk Factors in Patients with Breast Carcinoma in Pakistan

  • Memon, Zahid Ali;Qurrat-ul-Ain, Qurrat-ul-Ain;Khan, Ruba;Raza, Natasha;Noor, Tooba
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7467-7472
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    • 2015
  • Background: Breast cancer is known to be one of the most prevalent cancers among women in both developing and developed countries. The incidence of breast cancer in Pakistan has increased dramatically within the last few years and is the second country after Israel in Asia to have highest proportional cases of breast cancer. However, there are limited data for breast cancer available in the literature from Pakistan. Objectives: The study was conducted to bring to light the common clinical presentation of breast cancer and to evaluate the frequency of established risk factors in breast carcinoma patients and furthermore to compare the findings between premenopausal and postmenopausal women in Pakistan. Materials and Methods: A 6 months (from July 2012 to Dec 2012) cross sectional survey was conducted in Surgical and Oncology Units of Civil Hospital, Karachi. Data were collected though a well developed questionnaire from 105 female patients diagnosed with carcinoma of breast and analyzed using SPSS version 17. Institutional ethical approval was obtained prior to data collection. Results: Out of 105 patients, 43 were premenopausal and 62 were postmenopausal, 99 being married. Mean age at diagnosis was $47.8{\pm}12.4years$. A painless lump was the most frequent symptom, notived by 77.1%(n=81). Some 55.2% (n=58) patients had a lump in the right breast and 44.8%(n=47) in the left breast. In the majority of cases, the lump was present in upper outer quadrant 41.9% (n=44). Mean period of delay from appearance of symptoms to consulting a doctor was $5.13{\pm}4.8months$, from the shortest 1 month to the longest 36 months. Long delay (> 3 months) was the most frequent figure 41.9%. Considering overall risk factors most frequent were first pregnancy after 20 years of age (41%), physical breast trauma (28.6%), lack of breast feeding(21.9%), and early menarche <11 years (19%), followed by null parity (16.2%), consumption of high fat diet (15.2%), family history of breast cancer or any other cancer in first degree relatives (9.5% and 13.3%, respectively). Some of the less common factors were late menopause >54 years (8.6%), use of oral contraceptive pills (10.5%), use of hormone replacement therapy (4.7%),smoking (4.7%) and radiation (0.96%). Significant differences (p<0.005) were observed between pre and post menopausal women regarding history of physical breast trauma, practice of breast feeding and parity. Conclusions: A painless lump was the most frequent clinical presentation noted. Overall age at first child > 20 years, physical breast trauma, lack of breast feeding, early menarche <11 were the most frequent risk factors. Physical breast trauma, lower parity, a trend for less breast feeding had more significant associations with pre-menopausal than post-menopausal onset. Increase opportunity of disease prevention can be obtained through better understanding of clinical presentation and risk factors important in the etiology of breast cancer.

The Effects of Acute Hemorrhage on Cardiopulmonary Dynamics in the Hypothermic Dog (급성사혈이 저온견의 심폐동태에 미치는 영향)

  • Lee, Jae Woon
    • Journal of Chest Surgery
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    • v.2 no.1
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    • pp.85-104
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    • 1969
  • This experiment was carried out to study the effect of rapid hemorrhage on cardiopulmonary hemodynamics of the cooled dogs. Hypothermia was induced by means of body surface cooling with ice water. Lowest esophageal temperatures ranged from 24 to 26 degree. Dogs were bled via the femoral artery into a reservoir in amount of the equivalent blood volume of 3% of body weight of the dogs. Some dogs were reinfused with the same amount of blood which they lost and others infused with 5% dextrose solution. Fourty adult mongrel dogs were divided into three groups: group I[15 dogs]; dogs were bled in normothermic state. Five dogs had no further treatment, but five dogs were reinfused with blood and five infused with 5% dextrose solution 30 minutes after bleeding. GroupII[10 dogs]; dogs were bled as group I after having been cooled. Five dogs were reinfused with blood as group I. Group III[15 dogs]; dogs were first bled and then cooled. Reinfusion procedures were the same as in group l Results were as follow: 1. The heart rate showed a slight decrease after bleeding in group I and then increased over the control level after 60 minutes. After reinfusion and infusion, the heart rate was also increased gradually and after three hours almost returned to the control level. In group II and groupIll, the heart rate decreased remarkably and after reinfusion showed a light increase but after infusion tended to decrease cotinually. 2. The stroke volume showed remarkable decrease after bleeding in group I., and recovered to control level after reinfusion and infusion,and then gradually decreased again. In group III, the stroke volume showed no remarkable change after hypothermia, and tended to decrease after reinfusion. In group III, the stroke volume decreased remarkably after bleeding and hypothermia,and clearly increased after reinfusion and infusion and then returned to control level. 3. Femoral mean pressure declined very rapidly and significantly right after bleeding and showed a remarkable prompt rise after reinfusion and infusion in group I [67% recovery]. On the other hand, it declined remarkably after hypothermia and bleeding and showed a slight rise after reinfusion and infusion in group II[46% recovery] and III [41% recovery]. 4. Venous pressure declined slightly after bleeding and tended to return to the control level after reinfusion and infusion,in group I. In group II, it did not change significantly during hypothermia but showed a slight decline after bleeding and returned toward control level after reinfusion. In group III, it declined slightly after bleeding and showed no significant change after hypothermia and rose over the control level after reinfusion and infusion. 5. Right ventricular systolic pressure decreased markedly after bleeding and then increased progressively after 30 minutes. It increased after reinfusion and infusion as well, approaching the control level in group I. In group II, it showed no significant change during hypothermia, but decreased remarkably after bleeding and then returned to near control level after reinfusion. In group III, it was decreased markedly after bleeding but did not change significantly during hypothermia and showed a slight increase after reinfusion. 6. The respiratory rate increased gradually after bleeding and decreased gradually after reinfusion but did not return to the control level, whereas it decreased near to the control level after infusion,and tended to increase in group I. In group II, it decreased significantly after hypothermia and bleeding but returned near to the control level after reinfusion. In group III, it showed a remarkable decrease after hypothermia and increased slightly after reinfusion and infusion but did not returned to the control level. In group I, the tidal volume decreased slightly after hemorrhage, and increased gradually to near the control level after 3 hours following reinfusion.

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A STUDY ON THE REMOVAL TORQUE OF TITANIUM IMPLANTS (Titanium Implant의 Removal Torque에 관한 연구)

  • Lee, June-Seok;Kim, Yung-Soo;Kim, Chang-Whe
    • The Journal of Korean Academy of Prosthodontics
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    • v.32 no.1
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    • pp.148-169
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    • 1994
  • The concept of biologic attachment of load-bearing implants has developed over the past decades as an alternative to the difficulties associated with long term implantation using mechanical fixation and bone cement. The choice of implant material is also as critical an element as site preparation or insertion procedure. The properties of implants that affect host tissue responses are not limited to chemical composition alone, but also include shape, surface characteristics, site of implantation, and mechanical interaction with host tissues. Initial mechanical interlocking prevents micromotion and may be a prerequisite for direct bone apposition. A hard tightening of screws does not necessarily mean a stronger fixation and final tightening of the fixtures is dependent on the experience of the operator. Removal torque is lower than insertion torque. The purpose of this study was to investigate differences in the removal torques at the bone-implant interface of polished and sandblasted Titanium. This experiment will give insight into important factors that must be considered when interpreting in vivo screwing forces on implants during the connection of the transmucosal abutments. We evaluated the significance of different surface textures by comparison of the withdrawal forces necessary for removal of otherwise identical rough and polished implants of Titanium and also evaluated interfacial response on the light microscopic level to implant surface. And the priority of the area of insertion on osseointegration were evaluated. 9 Titanium implants - among them, 3 were for the developmental - of either a smooth or rough surface finish were inserted in the dog mandible in the right side. 3 months later Kanon Torque Gauge was used to unscrew the implants. The results were as follows : 1. No significant difference was seen in the removal torque due to variation in surface treatment, 23 Ncm for the sandblasted and 23.33 Ncm for the polished surface (p>0.05). 2. Implants in the anterior (25 Ncm) mandible showed better resistance to unscrewing in comparison to ones in the posterior (18 Ncm) region (p<0.05). 3. Developmental fixtures (22 Ncm) had similar pullout strength to the control group (p>0.05).

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