• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.4
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• pp.301-308
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• 2007

Purpose: This study was performed to compare and evaluate the effect of recipient site depths and diameters of the drills on the primary stability of implant in pig's ribs. Materials and methods: An intact pig's rib larger than 8 mm in width and 20 mm in height; RBM(resorbable blasting media) surface blasted ${\phi}3.75mm$ and 8.0 mm long USII Osstem Implants (Osstem Co., Korea) were used. To measure the primary stability, $Periotest^{(R)}$ (Simens AG, Germany) and $Osstell^{TM}$ (Model 6 Resonance Frequency Analyser: Integration Diagnostics Ltd., Sweden) were used. They were divided into 6 groups according to its recipient site formation method: D3H3, D3H5, D3H7, D3.3H3, D3.3H5, D3.3H7. Each group had, as indicated, 10 implants placed, and total 60 implants were used. The mean value was obtained by 4-time measurements each on mesial, distal, buccal, and lingual side perpendicular to the long axis of the implant using $Periotest^{(R)}$ and $Osstell^{TM}$. For statistical analysis one-way ANOVA was used to compare the mean value of each group, and the correlation between placement depths and the primary stability, and that of measuring instruments was analyzed using SPSS 12.0. Results: The primary stability of the implants increased as the placement depths increased (p<0.05), and showed a proportional relationship (p<0.01). The primary stability increased when the diameter of the recipient site was smaller than that of the implant but with no statistical significance. There was a strong correlation between $Osstell^{TM}$ and $Periotest^{(R)}$ (p<0.01). Conclusion: These results suggest that increasing the placement depth of implants enhances the primary stability of implant.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.279-289
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• 1995

This study was designed 1) to develop a hypertensive animal model in which the blood pressures (BPs) of symmetric regions (right and left upper extremities) are significantly different and 2) to test the effect of BP per se on the contractility and endothelium-dependent relaxation of vascular smooth muscle. Rabbits were anesthetized with sodium pentobarbital and ventilated with room air via animal respirator. The transverse aorta was exposed through the left second intercostal space and the lumen of the aorta was narrowed partially by ligation using 3-0 silk and a probe at a point between the origins of the brachiocephalic trunk and the left subclavian artery. Four to eight weeks postoperatively, BPs were measured in the carotid artery as the high BP area (proximal to coactation site) and in the femoral artery as the low BP area (distal to coarctation site). In the animal model, pressure-overload hypertension was developed and the BP of the right subclavian artery was higher than that of the left subclavian artery. The concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II were measured. The right and left subclavian arteries and their branches were used for isometric tension recording in organ baths and their responsiveness to phenylephrine, serotonin, acetylcholine, and sodium nitroprusside were examined. The BPs of carotid and femoral artery in control animals were $116{\pm} 12/75{\pm}9\;mmHg (mean ${\pm}SEM$) and $130{\pm}16/68{\pm}9\;mmHg$ respectively, while those of carotid and femoral artery in the hypetensive animals were $172{\pm}6/111{\pm}10\;mmHg$ and 136{\pm} 4/100 {\pm}9\;mmHg$ respectively. There were no significant differences in the concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II between controls and the animal models. No significant differences were found in the vascular sensitivities to phenylephrine and serotonin between the high pressure-exposed vessels and the low pressure-exposed vessels. However, the endothelium-dependent relaxation to acetylcholine and nitroprusside-induced relaxation showed significant differences between the high pressure-exposed and the low pressure-exposed subclavian arteries. From the above results, we suggest that the contractility of vascular smooth muscle is unchanged by the elevated pressure per se. However, the endothelium-dependent relaxation to acetylcholine and the nitroprusside-induced relaxation are attenuated by pressure.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.6
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• pp.928-939
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• 2003

A study was carried out to determine the effect of de-hulling on apparent and true ileal amino acids digestibility of soybean meals for growing pigs. Twenty barrows (Duroc${\times}$Large white${\times}$Longer white) were fitted with a simple T-cannula at the distal ilium. Digestibility of 20 experimental diets was determined, nine of them were de-hulled soybean meal diets, and nine of them were regular soybean meal diets and two low protein casein diets for determination of endogenous amino acid correction for true digestibility determination. A TEX>$5<{\times}5<$ Latin Squares Design was adopted in this trail. The results showed that de-hulling increased apparent ileal digestibility of isoleucine, threonine, aspartic, tyrosine and indispensable and dispensable amino acid (p<0.05) in soybean meals. Furthermore, dehulling is also increased apparent digestibility of arginine, leucine, lysine, phenylalanine, alanine, glutamic acid, serine and gross amino acids (p<0.01). However, there were no significant differences found for histidine, methionine, tryptophan, cystine and glycine (p>0.05). Similar responses were found for true ileal digestibility. In three dehulled and non-dehulled pairs soybean meals from the same respective sources, de-hulling increased apparent digestibility of lysine, methionine, threonine and cystine 1.42%, 2.06%, 2.18% and 1.40% respectively. True digestibility of lysine, methionine, threonine and cystine was increased 1.65%, 1.94%, 2.30% and 1.82% respectively. A prediction equation for true ileal amino acid digestibility (including lysine and arginine) was established by multivariate linear regression. The independent variables included relevant amino acid, organic matter, crude protein, ether extract and nitrogen free extract. The coefficient R2 values of lysine and agrinine were 0.596 and 0.531 respectively. According to the crude protein content, a prediction equation for lysine and arginine content in soybean meal was also established by single linear regression. The coefficient $R^2$ values of lysine and agrinine were 0.636 and 0.636 respectively.

• The korean journal of orthodontics
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• v.14 no.2
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• pp.203-215
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• 1984

This experiment was performed to explore the effect of electric currents and orthodontic forces on bone $PGE_2$ content and orthodontic tooth movement on cats. Stainless steel electrodes were connected a power pack consisting of five miniature batteries, a transistor, and a resistor. The current $(10{\pm}2{\mu}A)$ was provided by a constant source encased in a palatal acrylic plate. In first experiment, the cathode was placed mesial to the right maxillary canine tooth and the anode was positioned distal to the tooth, Sham electrodes were placed new the left cuspid, to serve as control. Nine cats were divided into three groups evenly. Groups of three animals were treated with electric currents only-for 1, 3 and 7 days, respectively. In second experiment, electric currents and the orthodontic forces of about 80 gm were applied to the right maxillary canine, and the orthodontic forces only were applied to the left maxillary canine. 3 groups of three cats each were treated in this experiment-for 1, 3 and 7 days, respectively. Alveolar bone samples were obtained from sites of tension and compression as well as from contralateral sites. Bone samples were extracted by homogenization in $40\%$ ethanal. The supernatant partitioned twice with 2 volumes of petroleum ether to remove neutral lipids and the aqueous supernatant partitioned in ethyl acetate. After drying the solvent, $PGE_2$ was measured by radioimmunoassay technique. The obtained results were as follows. 1. Teeth treated with combined force and electricity moved faster than those treated with force alone. 2. Alveolar bone $PGE_2$ content of electric stimulation was increased at both electrodes. 3. Alveolar bone $PGE_2$ content of mechanical stimulation at compression sites was gradually increased at all time period. At tension site, $PGE_2$ content increased after 1 day of mechanical stimulation remained elevated at all time period. 4. Alveolar bone $PGE_2$ content of compression sites was increased more than that of tension sites from mechanical stimulation as well as electrical stimulation.

• Journal of Periodontal and Implant Science
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• v.27 no.2
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• pp.363-377
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• 1997

The main goal of periodontal therapy is the regeneration of periodontal tissue which has been lost due to destructive periodontal diseases. Although conventional forms of periodontal therapy show sound clinical results, the healing results in long junctional epithelium. There have been numerous materials and surgical techniques developed for new attachment and bone regeneration. Bone grafts can be catagorized into: autografts, allografts, xenografts and bone substitutes. Synthetic bone substitute materials include hydroxyapatite, tricalcium phosphate, calcium carbonate, and Plaster of Paris. Calcium sulfate has found its use in dental practice for the last 30 years. Recent animal studies suggest that periodontal regeneration in 3 wall intrabony defect may be enhanced by the presence of calcium sulfate. And it is well known that 2 wall & 1 wall defect have less osteogenic potential, So we need to study the effect of calcium sulfate in 1 wall intrabony defect in dogs. The present study evaluates the effects of calcium sulfate on the epithelial migration, alveolar bone regeneration and cementum formation in intrabony defects of dogs. Four millimeter-deep one-wall intrabony defects were surgically created in the mesial aspect of anterior teeth and mesial & distal aspects of premolars. The test group received calcium sulfate grafts with a flap procedure. The control underwent flap procedure only. Histologic analysis following 8 weeks of healing revealed the following results: 1. The lengths of junctional epithelium were: 2.52mm in the control, and 1.89mm in the test group. There was no statistical significance between the two groups. 2. Alveolar bone formation were: 0.61mm in the control, and 1.88mm in the test group. There was a statistically significant difference between the two groups (p<0.05). 3. Cementum formations were: l.lmm in the control, and 2.46mm in the test group. There was a statistically significant difference between the two groups (p<0.05). 4. The length of CT adhesion were: O.97mm in the control, and 0.17mm in the test group. There was no statistically significant differences between the two groups These results suggest that the use of calcium sulfate in intrabony defects has little effect on junctional epithelium migration, but has significant effects on new bone and new cementum formations.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.847-854
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• 2015

The objective of this study was to determine the effects of graded inclusions of wheat bran (0%, 9.65%, 48.25% wheat bran) and two growth stages (from 32.5 to 47.2 kg and 59.4 to 78.7 kg, respectively) on the apparent ileal digestibility (AID), apparent total tract digestibility (ATTD) and hindgut fermentation of nutrients and energy in growing pigs. Six light pigs (initial body weight [BW] $32.5{\pm}2.1kg$) and six heavy pigs (initial BW $59.4{\pm}3.2kg$) were surgically prepared with a T-cannula in the distal ileum. A difference method was used to calculate the nutrient and energy digestibility of wheat bran by means of comparison with a basal diet consisting of corn-soybean meal (0% wheat bran). Two additional diets were formulated by replacing 9.65% and 48.25% wheat bran by the basal diet, respectively. Each group of pigs was allotted to a $6{\times}3$ Youden square design, and pigs were fed to three experimental diets during three 11-d periods. Hindgut fermentation values were calculated as the differences between ATTD and AID values. For the wheat bran diets, the AID and ATTD of dry matter (DM), ash, organic matter (OM), carbohydrates (CHO), gross energy (GE), and digestible energy (DE) decreased with increasing inclusion levels of wheat bran (p<0.05). While only AID of CHO and ATTD of DM, ash, OM, CHO, GE, and DE content differed (p<0.05) when considering the BW effect. For the wheat bran ingredient, there was a wider variation effect (p<0.01) on the nutrient and energy digestibility of wheat bran in 9.65% inclusion level due to the coefficient of variation (CV) of the nutrient and energy digestibility being higher at 9.65% compared to 48.25% inclusion level of wheat bran. Digestible energy content of wheat bran at 48.25% inclusion level (4.8 and 6.7 MJ/kg of DM, respectively) fermented by hindgut was significantly higher (p<0.05) than that in 9.65% wheat bran inclusion level (2.56 and 2.12 MJ/kg of DM, respectively), which was also affected (p<0.05) by two growth stages. This increase in hindgut fermentation caused the difference in ileal DE (p<0.05) to disappear at total tract level. All in all, increasing wheat bran levels in diets negatively influences the digestibility of some nutrients in pigs, while it positively affects the DE fermentation in the hindgut.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.355-372
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• 2002

The purpose of this study was to evaluate the effect of multiaxial lower extremity orthosis on correction of genu valgum. 20 volunteers among people visited department of Rehabilitation Medicine, chungnam national university hospital, who had been diagnosed as genu valgum without other musculoskeletal problems were included. 10 individuals(mean age: 9.gyrs) who had been taken multiaxial lower extremity orthosis at least 12month were included in experimental group and the other 10 individuals(mean age: 11.7yrs) refused taking this orthosis in the control group. We measured the Q-angle & femorotibial angle using plain roentgenogram images at visiting day and repeat same test after 1year follow up. Multiaxial lower extremity orthosis consist of proximal horizontal bar with both thigh cuff, central vertical bar and distal horizontal bar with both shoes. we narrowed inter-shoes distance from start to 6th month and inter-thigh cuff distance together with above correction for next 6month in the frontal plane and from 10th month, dorsiflexed both shoes in sagittal plane. Also, we rotate the both shoes externally and retract the proximal vertical bar every month. This orthosis have to be taken at least 4 hours during sleep. The result were as follows 1. There were no statistical significant difference in each parameter between the right and left Q-angle before multiaxial lower extremity orthosis. 2. The left Q angle reduced $-11^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 3. The right Q angle reduced $-13^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 4. There were no statistical significant difference in each parameter between the right and left femorotibial angle before multiaxial lower extremity orthosis. 5. The left femorotibial angle reduced $-10.1^{\circ}$ between 1st day and after lyear follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 6. The right femorotibial angle reduced $-11.2^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001).

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1491-1496
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• 2009

Stroke is usually associated with the cerebral blood flow of the central nervous system. However, studies concerning the effects of neurologic sysmptoms induced from stroke on the peripheral blood flow has not taken place sufficiently. To ascertain the feasibility of a blood flow meter adopting to use doppler ultrasonogrphy, under the prospect that hemiparesis induced from stroke may have effect on the peripheral blood flow, the peripheral blood flow velocity was observed. The control group made up of healthy people without any factors capable of effecting the peripheral blood flow velocity, and patient group which consist of hemiparetic people induced from stroke, were recruited. Volumes of recruitment are 21 persons in the patient group, and 29 persons in the control group, but the final numbers of people are 17 and 21 respectively because of the inconsistancy in the method of the test. The non-invasive method of Doppler effect of Ultrasound was used to measure the blood flow velocity. The blood flow velocity in the peripheral part of left and right fourth fingers:dorsal branches of proper palmar digital artery to dorsum of distal phalanges, was measured in the control group and patient group through Doppler Ultrasound. In comparison of the control group and the patient group, the systolic blood flow velocity from the peripheral part of the upper extremity was lower in the patient group than that of the control group. According to such results, it is concluded that hemiparesis induces the reduction of the peripheral blood flow velocity in the systolic phase.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.3
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• pp.176-182
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• 2020

Purpose: To evaluate the effects of load direction, number of implants, and alignment of implant position on stress distribution in implant, prosthesis, and bone tissue. Materials and Methods: Four 3D models were made to simulate posterior mandible bone block: two implants and 3-unit fixed dental prosthesis (FDP) with a pontic in the center (model M1), two implants and 3-unit FDP with a cantilever pontic at one end (model M2), FDP supported by three implants with straight line placement (model M3) and FDP supported by three implants with staggered implant configuration (model M4). The applied force was 120 N axially or 120 N obliquely. Results: Peak von Mises stresses caused by oblique occlusal force were 3.4 to 5.1 times higher in the implant and 3.5 to 8.3 times higher in the alveolar bone than those stresses caused by axial occlusal force. In model M2, the connector area of the distal cantilever in the prosthesis generated the highest von Mises stresses among all models. With the design of a large number of implants, low stresses were generated. When three implants were placed, there were no significant differences in the magnitude of stress between staggered arrangement and straight arrangement. Conclusion: The effect of staggering alignment on implant stress was negligible. However, the number of implants had a significant effect on stress magnitude.

• The Korean Journal of Physiology
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• v.22 no.1
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• pp.13-29
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• 1988

In order to elucidate the regulatory mechanism of intracellular calcium ion concentrations, contractions or contractures induced by $Na^{+}-removal$, calcium-application or ouabain-treatment as an index of $Na^+/Ca^{2+}$ exchange activity were studied in atrial muscle or vascular smooth muscle (aorta and renal artery) of the rabbit. The magnitude of low sodium contractures in atrial trabeculae increased with sigmoid shape when external sodium concentrations were reduced to sodium-free condition, whereas that of calcium contracture intensified in a parabolic pattern when external calcium concentrations were elevated to 8 mM. $Na^{+}-removal$ contractures were induced in a duration-dependent manner to $K^{+}-free$ exposure and same findings were observed with ouabain treatment. $Na^{+}-free$ contractures were not affected by verapamil treatment, but stimulated by $100{\mu}M\;Mn^{2+}$ and inhibited by high concentrations of $Mn^{2+}\;(2{\sim}8mM)$ in a dose-dependent manner. Ryanodine which is known to suppress the release of calcium from internal store abolished spontaneous twitch contractions induced by $K^{+}-free$ solution, but had no effect on the development $Na^{+}-free$ contractures. Na-free contractures were not always induced in vascular smooth muscle preparations. Contractures by $O\;mM\;Na^+$ were usually seen in aorta, but not often in renal artery.$50\;mM\;K^+$, noradrenaline (NA) and angiotensin II (AII) always evoked very large contraction in all preparations of vascular smooth muscle. Contractures developed by $O\;mM\;Na^+$ were not sensitive to verapamil treatment as in atrial trabeculae, but were abolished by $100{\mu}M\;Mn^{2+}$. In contrast to $Na^{+}-free$ contractures, $Mn^{2+}(100{\mu}M)$ had no effect on the contractures induced by NA or 50 mM$K^+$. Caffeine in the concentration of 10 mM evoked transient contracture in the distal renal artery. The rate of spontaneous relaxation in caffeine contracture was dependent upon the concentrations of external sodium, and had double component of relaxation when the rate of relaxation was plotted in the semilogarithmic scale of relative tension versus time. Especially late components of relaxation had more direct relation to $Na^+$ concentrations. It could be concluded that $Na^+/Ca^{2+}$ exchange mechanism in the heart has a large capacity, inhibited by $Mn^{2+}$ but not by verapamil and ryanodine, while $Na^+/Ca^{2+}$ exchange system in vascular smooth muscle has a very low capacity especially in small artery, inhibited by low concentration of $Mn^{2+}\;(100{\mu}M)$ but not affected by verapamil and ryanodine.