1.Comparative Study of Panoramic Mandibular Parameters in Postmenopausal Osteoporotic women.
Cheol Hun KIM ; Sang Hun SHIN ; Dong Kyu YANG
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2000;26(5):519-526
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
2.A STUDY OF THE STRESS DISTRIBUTION OF THE ABUTMENT AND SUPPORTING TISSUES ACCORDING TO THE SLOPES AND TYPES OF GUIDING PLANES OF THE LAST ABUTMENT IN DISTAL EXTENSION REMOVABLE PARTIAL DENTURE USING THREE DIMENSIONAL FINITE ELEMENTANALYSIS METHOD.
Yang Kyo KIM ; Cheong Hee LEE ; Kwang Hun JO
The Journal of Korean Academy of Prosthodontics 1999;37(5):581-596
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
3.Tuberculosis Cutis Orificialis of the Tongue.
Kee Yang CHUNG ; Seong Hyun PARK ; Seung Hun LEE
Korean Journal of Dermatology 1987;25(6):802-805
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
4.A Case of Lofgren' s Syndrome.
Seong Gyu YANG ; Dae Hun SUH ; Kwang Hyun CHO
Korean Journal of Dermatology 1995;33(5):931-934
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
5.Mechanisms of Increase in Renal Blood Flow During Partial Ureteral Obstruction in Dogs.
Hun Mo YANG ; Young Gi MIN ; Jae Eung YOO
Korean Journal of Nephrology 1998;17(5):686-691
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
6.Bone Age Determination and Hand Radiographic Findings in Children With Russell-Silver Syndrome.
Hun Kyu LIM ; Sei Won YANG ; Hyung Ro MOON
Journal of the Korean Pediatric Society 1989;32(6):823-833
No abstract available.
Child*
;
Hand*
;
Humans
;
Silver-Russell Syndrome*
7.Percutaneous Transluminal Coronary Angioplasty for Coronary Artery Stenosis in an Adult Kawasaki Disease with Coronary Aneurysm : A Case Report and Review.
Dong Hun CHOI ; Won Heum SHIM ; Mun Heung LEE ; Shi Hun PARK ; Yang Soo JANG ; Do Yeon LEE
Korean Circulation Journal 1994;24(3):528-535
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
8.A study on the fracture strength of collarless metal-ceramic fixed partial dentures.
Jong Wook YOON ; Sung Hun KIM ; Jai Bong LEE ; Jung Suk HAN ; Jae Ho YANG
The Journal of Advanced Prosthodontics 2010;2(4):134-141
PURPOSE: The objective of this study was to evaluate fracture strength of collarless metal-ceramic FPDs according to their metal coping designs. MATERIALS AND METHODS: Four different facial margin design groups were investigated. Group A was a coping with a thin facial metal collar, group B was a collarless coping with its facial metal to the shoulder, group C was a collarless coping with its facial metal 1 mm short of the shoulder, and group D was a collarless coping with its facial metal 2 mm short of the shoulder. Fifteen 3-unit collarless metal-ceramic FPDs were fabricated in each group. Finished FPDs were cemented to PBT (Polybutylene terephthalate) dies with resin cement. The fracture strength test was carried out using universal testing machine (Instron 4465, Instron Co., Norwood MA, USA) at a cross head speed of 0.5 mm/min. Aluminum foil folded to about 1 mm of thickness was inserted between the plunger tip and the incisal edge of the pontic. Vertical load was applied until catastrophic porcelain fracture occurred. RESULTS: The greater the bulk of unsupported facial shoulder porcelain was, the lower the fracture strength became. However, there were no significant differences between experimental groups (P > .05). CONCLUSION: All groups of collarless metal-ceramic FPDs had higher fracture strength than maximum incisive biting force. Modified collarless metal-ceramic FPD can be an alternative to all-ceramic FPDs in clinical situations.
Aluminum
;
Bites and Stings
;
Collodion
;
Dental Porcelain
;
Denture, Partial, Fixed
;
Head
;
Resin Cements
;
Shoulder
9.Comparison of polymer-based temporary crown and fixed partial denture materials by diametral tensile strength.
Seung Ryong HA ; Jae Ho YANG ; Jai Bong LEE ; Jung Suk HAN ; Sung Hun KIM
The Journal of Advanced Prosthodontics 2010;2(1):14-17
PURPOSE: The purpose of this study was to investigate the diametral tensile strength of polymer-based temporary crown and fixed partial denture (FPD) materials, and the change of the diametral tensile strength with time. MATERIAL AND METHODS: One monomethacrylate-based temporary crown and FPD material (Trim) and three dimethacrylate-based ones (Protemp 3 Garant, Temphase, Luxtemp) were investigated. 20 specimens (the empty set 4 mm x 6 mm) were fabricated and randomly divided into two groups (Group I: Immediately, Group II: 1 hour) according to the measurement time after completion of mixing. Universal Testing Machine was used to load the specimens at a cross-head speed of 0.5 mm/min. The data were analyzed using one-way ANOVA, the multiple comparison Scheffe test and independent sample t test (alpha = 0.05). RESULTS: Trim showed severe permanent deformation without an obvious fracture during loading at both times. There were statistically significant differences among the dimethacrylate-based materials. The dimethacrylate-based materials presented an increase in strength from 5 minutes to 1 hour and were as follows: Protemp 3 Garant (23.16 - 37.6 MPa), Temphase (22.27 - 28.08 MPa), Luxatemp (14.46 - 20.59 MPa). Protemp 3 Garant showed the highest value. CONCLUSION: The dimethacrylate-based temporary materials tested were stronger in diametral tensile strength than the monomethacrylate-based one. The diametral tensile strength of the materials investigated increased with time.
Acrylic Resins
;
Bisphenol A-Glycidyl Methacrylate
;
Collodion
;
Composite Resins
;
Crowns
;
Denture, Partial, Fixed
;
Methacrylates
;
Polymethacrylic Acids
;
Tensile Strength
10.Phylogenic Oto-stomatognathic Connection of the Mammalian Jaw: A Novel Hypothesis for Tensor Tympani Muscle and TMD-related Otologic Symptoms.
Hun Mu YANG ; Kyung Seok HU ; Hee Jin KIM
Korean Journal of Physical Anthropology 2015;28(2):63-67
Otologic complaints, including otalgia, tinnitus, vertigo, and hearing loss, are known to be related to temporomandibular disorders (TMDs). There have been several hypotheses regarding the clinical correlation between otologic complaints and TMDs, based on clinical phenomena with corresponding symptoms, the close neurological relationship between otic and masticatory structures, and anatomical features of the tympanic cavity and jaw joint. Function of the tensor tympani muscle seems to be crucial to understanding TMD-related otologic symptoms. The tensor tympani inserts into the handle of the malleus and it modulates sound transduction in situations of excessive noise. This muscle is innervated by the trigeminal nerve, like the masticatory muscles. Voluntary eardrum movement by pathological tensor tympani contraction results in various otologic symptoms. Thus, co-contraction of the tensor tympani with the masticatory muscle could be a possible cause of TMD-related otologic symptoms. The tensor tympani is rather unrelated to the acoustic reflex, in which the stapedius is strongly involved. The tensor tympani seem to be controlled by proprioceptive information from the trigeminal sensory nucleus. The peripheral innervation pattern of the tensor tympani and masticatory muscles is also supposed to be interconnected. The middle ear structure, including the malleus, incus, and tensor tympani, of mammals had been adapted for acoustic function and lacks the masticatory role seen in non-mammalian jawed vertebrates. The tensor tympani in non-mammals is one of the masticatory muscles and plays a role in the modulation of sound transduction and mastication. After the functional differentiation of the mammalian middle ear, the nervous connection of the tensor tympani with other masticatory apparatus still remains. Through this oto-stomatognathic vestige, the tensor tympani seems to contract unnecessarily in some pathological conditions of the TMD in which the masticatory muscles contract excessively. We hypothesized that the phylogenic relationship between the tensor tympani and masticatory apparatus is a significant and logical reason for TMD-related otologic complaints.
Acoustics
;
Ear, Middle
;
Earache
;
Hearing Loss
;
Incus
;
Jaw*
;
Joints
;
Logic
;
Malleus
;
Mammals
;
Mastication
;
Masticatory Muscles
;
Noise
;
Reflex, Acoustic
;
Stapedius
;
Temporomandibular Joint Disorders
;
Tensor Tympani*
;
Tinnitus
;
Trigeminal Nerve
;
Tympanic Membrane
;
Vertebrates
;
Vertigo