Osteoporosis has recently been recognized as a major health problem in the elderly population. The disorder is manifested as a loss of bone mass accompanied by structural alteration of bone and increased incidence of fracture. Mandible also may be affected. So, I evaluated panoramic views of 66 postmenopausal women for finding the possibility of useful diagnostic mandibular parmeters of osteoporosis. To know the correlationship between skeleton and mandible, the average of the bone mineral density of lumbar from 2nd to 4th by the dual energy X-ray absorptiometry(DEXA, LUNAR DPZ. USA), and age and mandibular parameters, that is, the number of residual teeth, alveolar ridge resorption ratio, panoramic mandibular index (PMI), mandibular cortical width (MCW), angular cortical thickness (ACT), ramus cortical thickness (RCT), morphology of mandibular inferior cortical (MIC) were compared. And I divided the all tested women to the osteoporotic group and non-osteoporotic group by the use of T-score-2.0, which was derived from skeletal bone mineral density (BMD). To find the correlationship of the each group with mandibular parameters, t-test and discriminant analysis were done. The results of the t-test were that all parameters were highly related with 2 groups (p<0.05). Especially ACT, MIC, age have had even higher correlationship than others (p<0.001). The results of the discriminant analysis by the use of these ACT, MIC and age were that the discriminant function was Z =-2.973+(-1.447)x(ACT)+1.131x(MIC score)+(0.052)x(age), the cutting score was 0.257 and the classification accuracy was 84.8%. Therefore I suggest that the consideration of the angular cortical thickness (ACT), the age of patient and the morphology of mandibular inferior cortical(MIC) may help find the osteoporosis.
Aged ; Alveolar Process ; Bone Density ; Classification ; Female ; Humans ; Incidence ; Mandible ; Osteoporosis ; Skeleton ; Tooth

A tender, non-healing ulcer of 3 months' duration developed on the tongue tip of a 51-year-old male with active pulmonary tuberculosis. Acid-fast bacilli were grown in the tissue and sputum cultures. The patient was anergic to PPD skin test before the treatment and IL-2 productivity was significantly decreased. Sections from the tongue tip showed ulceration, infiltration of neutrophils and tuberculoid granulornas accompanying caseation necroses in the dermis. The ulcer healed after administration of anti-tuberculosis medication for 2 months.
Dermis ; Efficiency ; Humans ; Interleukin-2 ; Male ; Middle Aged ; Necrosis ; Neutrophils ; Skin Tests ; Sputum ; Tongue* ; Tuberculosis* ; Tuberculosis, Pulmonary ; Ulcer

Sarcoidosis is a rare d:sease in Korea and its association with erythema nodosurn is even rarer. Recently we saw a patient of bihilar adenopathy, who had arthralgia and erythematous nodules of both lower legs. A skin biopsy obtained from the erythematous nodule of the lower leg showed septal panniculitis, consitent with erythema nodosum, and a biopsy from the mediastinal lymph node revealed a pathology consistent with sarcoidosis. This is the first case of Lofgrens syndrome confirmed by histology ir, Korea.
Arthralgia ; Biopsy ; Erythema ; Erythema Nodosum ; Humans ; Korea ; Leg ; Lymph Nodes ; Panniculitis ; Pathology ; Sarcoidosis ; Skin

The purpose of this study was to investigate the stress distribution of the abutment and supporting tissues according tot he slopes and types of the guiding plane of distal extension removable partial dentures. The 3-dimensional finite element method was used and the finite element models were prepared as follows. Model I : Kratochvil type guiding plane with 90degree to residual ridge Model II : Kratochvil type guiding plane with 95degree to residual ridge Model III : Kratochvil type guiding plane with 100degree to residual ridge Model IV : Krol type guiding plane with 90degree to residual ridge Distal extension partial denture which right mandibular first and second molar were lost was used and the second premolar was prepared as primary abutment with RPI type retainer. Then 150N of compressive force was applied to central fossae of the first and second molars and von Mises stress and displacement were measured. The results were as follows : 1. Model I and Model IV showed a similar stress distribution pattern and the stress was concentrated on the apex of the root of the abutment. 2. The stress was increased and concentrated on mesial side of the root of the abutment in Model II. The stress was concentrated on buccal and mesiobuccal side of the root of the abutment in Model III. 3. In Model I, the root of the abutment displaced and twisted a little in clockwise. In Model IV, the root of the abutment displaced to distolingually at apical region of the root and mesiobucally at cervical region of the root. 4. In Model II, the root of the abutment displaced to mesiolingually at apical region of the root and more displaced and twisted in counterclockwise at cervical region of the root. In Model III, the root of the abutment displaced to mesiobucally at apical region of the root and more displaced and twisted in clockwise at cervical region of the root.
Bicuspid ; Denture, Partial ; Denture, Partial, Removable* ; Molar

Although tubuloglomerular feedback (TGF) is involved in ureteral obstruction-induced increase in renal blood flow (RBF), its contribution to RBF is not well established due to the concommitant increases in prostaglandin (PG) and renal interstitial fluid pressure (Pisf), both of which affect RBF one way or the other. Since Pisf and TGF are closely affected by renal hemodynamics, RBF will respond differently to increases in ureteral pressure depending on renal hemodynamic conditions. Therefore, the purpose of the present study was to investigate how the changes in renal hemodynamics affect the response of RBF to increases in ureteral pressure. The effect of PG on RBF was assessed by comparing the effects obtained before and after indomethacin, a cyclooxygenase inhibitor. Six anesthetized dogs were prepared with flow probes and inflatable silastic occluder around the renal artery, the ureteral catheter with its free end attached to a water reservoir, and the arterial and venous catheters. RBFs were obtained at ureteral pressures of 0, 15, and 40cmH2O during the maintenance of the renal artery pressure (RAP) at the level of systemic arterial pressure, 10mmHg above and below the lower autoregulatory limit of RBF (65+/-4 mmHg) both before and after indomethacin administration (10mg/kg). In response to the ureteral pressure of 40cmH2O, RBF increased from 172+/-6 to 185+/-10ml/min when RAP's were equal to systemic arterial pressure and decreased from 162+/-10 to 120+/-9 ml/min when RAP's were 55+/-4mmHg. Indomethacin pretreatment, depending on the level of RAP either prevented an increase or augmented a decrease in RBF in response to ureteral pressure elevation. This suggests that RAP-dependent changes in susceptibility of the renal venous system to compression by increased Pisf is the main mechanism by which the changes in renal perfusion pressure modulate the response of RBF to ureteral pressure elevation.
Animals ; Arterial Pressure ; Catheters ; Dogs* ; Extracellular Fluid ; Hemodynamics ; Indomethacin ; Perfusion ; Prostaglandin-Endoperoxide Synthases ; Renal Artery ; Renal Circulation* ; Ureter* ; Ureteral Obstruction* ; Urinary Catheters ; Water

No abstract available.
Child* ; Hand* ; Humans ; Silver-Russell Syndrome*

We experience coronary artery aneurysm and coronary artery stenosis in an adult as complications of Kawasaki disease. The patient suffered from ischemic heart disease due to coronary artery aneurysm and stenosis, We carried out PTCA and stenting at stenotic coronary artery successfully. A brief review of related literature was made.
Adult* ; Aneurysm ; Angioplasty, Balloon, Coronary* ; Constriction, Pathologic ; Coronary Aneurysm* ; Coronary Stenosis* ; Coronary Vessels* ; Humans ; Mucocutaneous Lymph Node Syndrome* ; Myocardial Ischemia ; Stents

Dental restorative materials must have the physical properties to withstand wear and corrosion. Base metal alloys possess better mechanical properties and lower price than the gold alloys. For these reason such alloys have largely replaced the precious metal alloys. One aspect to consider is the release of metal substances to oral environment. The release of elements from dental alloys is a continuing concern because the elements may have the potentially harmful biological effects on local tissue. The purpose of this study was to minimize metal release on the nonprecious metal surfaces by ion bea assisted deposition(IBAD) of titanium nitride (TiN). Ni-Cr-Be alloys with and without TiN coatings were secured in an wear test machine opposing ruby ball to determine their relative resistance to wear with 100m, 200m, 300m and 400m sliding distance. And the corrosion behavior of the Ni-Cr-Be alloys with and without TiN coating and 3 dental noble alloys have been studied. Potentiodynamic curves were used to analyse the corrosion characteristics of the alloys. The measurement of the released Ni and Ci ions was conducted by analysis of the electrolyte solution with atomic absorption spectroscopy. The results were as follows : 1. The critical sliding distance that wore down TiN coating of 2.5micrometer thickness in this study condition was 300m. 2. Ion beam assisted deposition of TiN showed a good surface modification with respect to the properties of wear and corrosion resistance. 3. X-ray diffraction showed that the strongest peak of TiN(111) in the coatings. 4. The release of Ni and Cr ions from alloys measured by means of atomic absorption spectroscopy was reduced by ion beam assisted deposition of TiN.
Absorption ; Alloys* ; Corrosion ; Dental Alloys ; Gold Alloys ; Ions ; Spectrum Analysis ; Tin* ; Titanium ; X-Ray Diffraction

The success of porcelain laminate veneer depends on the bond strength between tooth structure and ceramic restoration and the design of tooth preparation. In particular, incisal coverage and incisal finish line are the two most important factors in long-term fracture resistance. Although the majority of clinicians are practicing incisal coverage and there are various opinions on the geometrical ratio between the clinical crown length of the remaining tooth structure and the length of incisal extension in porcelain laminate veneer and the optimal incisal finish lines, scientific evidence still leaves much to be desired. The purpose of this study was to determine the effects of the amounts of incisal coverage and the types of incisal finish line on th stress distribution in maxillary anterior porcelain laminate veneers under two different loading conditions. Three-dimensional finite element models of a maxillary anterior porcelain veneer with different amounts of incisal coverage ; 0, 1, 2, and 3mm and different incisal finish lines ; feathered edge, incisal bevel, reverse bevel and lingual chamfer with various amounts of lingual extension were developed. 300N force was applied at the point 0.5mm cervical of the linguoincisal edge in two loading conditions ; A) 125 degrees, B) 132 degrees. tensile and compressive stress in ceramic and shear stress in the resin cement layer wee analyzed using three-dimensional finite element method. The results were as follows : 1. The types of incisal finish line had more influence on the stress distribution in porcelain laminate veneer than the amounts of incisal coverage. 2. In case of no incisal coverage, incisal beveled laminate exhibited more evenly distributed tensile stress than feathered edged laminate. And in case of incisal coverage, reverse beveled laminate and lingual chamfered laminate with 1mm lingual extension exhibited more evenly distributed tensile stress than lingual chamfered laminates with 2 mm and 3mm lingual extension. 3. As long as the lingual chamfer goes, less tensile stress was found at the incisal edge, while much more tensile stress was found at the lingual margin area in proportion to length of lingual extension. 4. Under 125 degree load, tensile stress in porcelain laminate veneer had increased compared with that under 132 degree load and the difference exhibited by the change of the amount of tooth support was larger. 5. The types of incisal finish line and the distance from the incisal finish line to the loading point had more influence on the shear stress distribution in the resin cement layer than the amount of incisal coverage. In contrast loading condition had little influence.
Animals ; Ceramics ; Crowns ; Dental Porcelain* ; Feathers ; Finite Element Analysis* ; Resin Cements ; Tooth ; Tooth Preparation

Purpose: The purpose of this study is to use finite element analysis to predict the fatigue life of an implant system subjected to fatigue load by mastication (chewing force). The reliability and the stability of implant system can be defined in terms of the fatigue strength. Not only an implant is expensive but also it is almost impossible to correct after it is inserted. From a bio-engineering standpoint, the fatigue strength of the dental implant system must be evaluated by simulation (FEA). Material and Methods: Finite element analysis and fatigue test are performed to estimate the fatigue strength of the implant system. Mesh of implant is generated with the actual shape and size. In this paper, the fatigue strength of implant system is estimated: U-fit (T.Strong, Korea, internal type). The stress field in implant is calculated by elastic-plastic finite element analysis. The equivalent fatigue stress, considering the contact and preload stretching of a screw by torque for tightening an abutment, is obtained by means of Sine's method. To evaluate the reliability of the calculated fatigue strength, fatigue test is performed. Results: A comparison of the calculated fatigue strength with experimental data showed the validity and accuracy of the proposed method. The initiation points of the fatigue failure in the implant system exist in the region of high equivalent fatigue stress values. Conclusion: The above proposed method for fatigue life estimation can be applied to other configurations of the differently designed and improved implant. In order to prove reliability of prototype implant, fatigue test should be executed. The proposed method is economical for the prediction of fatigue life because fatigue testing, which is time consuming and precision-dependent, is not required.
Bioengineering ; Dental Implants ; Fatigue* ; Finite Element Analysis ; Korea ; Mastication ; Torque