To compare several porcelains made by various manufacturers in shrinkage after firing and investigate the effect of condensation on shrinkage, specimens were prepared and the volume of each body was measured by the phase-shifting profilometry. Baseplate wax was cut by 2.5cmx2cm and cast in nonprecious metal (Verabond, U.S.A.). then any surfaces of specimens were abrased and polished on the SiC abrasing papers, preparing 120 specimens. specimens were divided into six groups according to the porcelain used, and the porcelain used in each group were as follows. Group I : Ceramco dentin porcelain Group II : Creation dentin porcelain Group III : Creation margin porcelain Group IV : Vintage margin porcelain Group V : Vita dentin porcelain Group VI : Vintage dentin porcelain Porcelain was built up on the metal plates using a small spoon and then solution matching to each porcelain was added. The six groups are subdivided into a and b. In subgroup a, only excessive solution was absorbed with tissue and in subgroup b, porcelain was condensed sufficiently. When build-up was completed, the shape was measured using the phase-shifting profilometry. After that, specimens were fired in the furnace programed for each porcelain and then their changed shape were measured again. Using the difference between the two above measurements, the ratio of shrinkage was calculated. Obtained results were as follows ; 1. Regardless of condensation, the volume of fired specimens were not different significantly between the two subgroups a and b in the same group. 2. The ratios of shrinkage were significantly higher in the groups porcelain built-up was condensed than in the groups not condensed. 3. The ratios of shrinkage were in the range of 36.81-27.19% in the groups porcelain built up was condensed and 44.52-37.54% in the other groups not condensed.
Dental Porcelain* ; Dentin ; Fires*

Singapore progressed to DORSCON Orange on 7 February 2020 when a local case with no history of travel out of Singapore was confirmed COVID-19 positive. With the impending lockdown, decision was made to move all postgraduate programs online. The objectives of this paper are to document early experiences and lessons learnt in the conversion of face-to-face to online teaching; and to conduct a literature search for tips on effective online teaching.

Snakebite is very common especially in Asia. We report a rare case of Providencia rettgeri infection following snakebite on the foot. This patient was treated with early and aggressive wound debridement, daily wound dressing during hospitalization and then skin coverage with split skin graft. No anti venom was given administered. Appropriate intravenous antibiotics were given to the patient while hospitalized and oral antibiotic were prescribed upon discharge. The outcome of this treatment was successful.
Orthopaedic

Segmental Spinal Instrumentation is effective operative procedure in unstable fracture and fracture-dislocation of the thoracolumbar spine, providing rigid spinal stability and reduces needs of external support and complications. Fifty nine patients with unstable fracture and fracture-dislocation of thoracolumbar spine were treated with Harrington rod instrumentation and sublaminar wiring(31 patients) and Luque rod instrumentation with sublaminar wiring(28 patients) in Hyun Dai Hae Seong Hospital, Ulsan, Paik Hospital, Pusan from Dec. 1983 to April 1986. We have analyzed the results of treatment about two type of S.S.I. and obtained following conclusions; l. In 59 patients, T12 level injury was 17 cases, Ll level was 25 cases and so T12 and Ll involvement were 71%. 2. By Francis Denis classification, 28 cases were burst type fracture, 20 cases were fracture-dislocation type, 6 cases were seat belt type and 5 cases were wedge compression type. 3. In Harrington rod with S.S.I., initial kyphotic angle was 22.4° and postoperative angle was 7.4° and correction rate was 66.9%; in Luque rod with S.S.I., preoperative kyphotic angle was 21.7° and postoperative angle was 6.5° and correction rate 69.6%. So there was no difference of correction rate in two type of S.S.I. 4. In Harrington rod with S.S.I., the loss of reduction was 1.2° and the loss was 7%; in Luque rod with S.S.I., the loss of reduction was 7.2° and the loss rate was 48%. So the loss of reduction of Luque rod with S.S.I. was greater than that of Harrington rod with S.S.I. 5. After removal of implants, Luque rod with S.S.I. patients have better range of motion than Harrington rod with S.S.I. patients clinically, but it needs more follow-up because of a few cases(18 cases).
Busan ; Classification ; Follow-Up Studies ; Humans ; Range of Motion, Articular ; Seat Belts ; Spine ; Surgical Procedures, Operative ; Ulsan

No abstract available.
Humans ; Statistics as Topic*

PURPOSE: To evaluate the incidence,. degree, and clinical significance of non-obstructive intrahepatic bile duct di'latation encountered on follow up CT after gastrectomy for gastric carcinoma. MATERIALS AND METHODS: We retrospectively analyzed follow-up abdominal CT of 65 patients who had undergone gastrectomy with truncal vagotomy and subtotal gastrectomy for gastric carcinoma. We classified those patients who showed intrahepatic duct dilatation into non-obstructive or obstructive groups depending on the presence or absence of the lesions obstructing the duct. We also evaluated the incidence, degree and pattern, and appearance time of non-obstructive type of duct dilatation. RESULTS: Non-obstructive and obstructive biliary dilatations were present in 8 cases(12.3%) and 9 cases(13. 8%), respectively. The degree of non-obstructive group was mild in 6 cases(75%) and moderate in 2 cases (25%) who had taken cholecystectomy during the follow up period, and patterns were proportional dilatation of the central and peripheral intrahepatic ducts. It appeared on follow up CT obtained 6 to 12 months after operation in 7 cases and 3.5 months in one case. No statistical significance was noted between the type of surgery and the incidence of non-obstructive dilatation(p>0.05). CONCLUSION: Mild dilatation of the central intrahepatic ducts without evidence of mechanical biliary obstruction can be seen on follow-up CT obtained more than 6 months after gastrectomy for gastric carcinoma, and the incidence is about 12%. We think that this finding is non-obstructive and clinical evaluation is unnecessary.
Bile Ducts, Intrahepatic ; Cholecystectomy ; Dilatation* ; Follow-Up Studies ; Gastrectomy* ; Humans ; Incidence ; Retrospective Studies ; Tomography, X-Ray Computed ; Vagotomy, Truncal

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

No abstract available.
Embryo Transfer* ; Embryonic Structures* ; Fertilization in Vitro* ; Pregnancy*

According to repeated measurements and correction procedures, the accuracy of the phase-shifting profilometry was developed. At first, after 20 final models for maxillary complete denture were duplicated, the mucosa surfaces of models were measured with the phase-shifting profilometry and each mirror view of these was calibrated. Maxillary cats were divided into 4 groups of 5 casts per each, and wax dentures with 2 sheets of baseplate wax and artificial teeth were made and then cured according to the curing method of each group. Group I ; quick curing with QC-20 acrylic resin Group II ; 9 hour curing with QC-20 acrylic resin Group III ; SR-Ivocap system Group IV ; metal base and quick curing with QC-20 acrylic resin After curing, polishing, and storing at 37degrees C n saline for 30 days, the forms of the impression surface of the dentures were measured with the phase-shifting profilometry. Then, the impression surface form of each denture was placed in the optimal position of comparison with the mirror view of the same final cast. The amount and direction of distortion of each denture was analyzed and the effects of polishing and storage in each denture were compared. The obtained results were as follows : 1. In Group I, the denture was observed as the appearance distorted in the opposite direction of the mucosa and the postero-lateral part of palatal portion of the denture was observed as the appearance separated from the mucosa. Also, the buccal flanges of the denture were observed as the appearance distorted in the direction of the mucosa. 2. In Group II, the postero-lateral part of palatal portion of the denture was observed as the appearance separated slightly from the mucosa. The bilateral buccal flanges of denture were observed as the appearance distorted severely in the direction of the mucosa. 3. In Group III, the bilateral part of the residual ridge crest portions and the buccal flanges of the denture were observed as the appearance distorted in the direction of the mucosa, and specially, the buccal flanges of the maxillary tuberosities were distorted severely. 4. In Group IV, the acrylic resin base of the buccal portion of the denture was observed as the appearance distorted in the opposite direction of the mucosa. 5. The phase-shifting profilometry, done with repeated measurements and correction procedures, was effective in comparing the amount and direction of distortion at every position after the laboratory work and the delivery of maxillary complete denture.
Animals ; Cats ; Denture, Complete ; Dentures* ; Mucous Membrane ; Tooth, Artificial

OBJECTIVES: the aim of this study was to evaluate plasmin system in placenta fiom women with normal and preeclamptic pregnancy. METHODS: The levels of urokinase-type plasminogen activator(uPA), tissue-type plasrninogen activator(tPA), uPA receptor(uPAR) and plasminogen activatar inhibitor-1(PAI-1) mRNAs were measured by Northern blotting in placenta hom sixteen women with normal (n""8) and preeclamptic (n""8) pregnancy. The levels of tPA protein and PAI-1 protein were also measured by Westerrn blotting. RESULTS: Densitometric measurements revealed no difference in the levels of uPA mRNA, uPAR mRNA, tPA protein and PAI-1 protein in placentas fiom normal and preeclamptic pregnancies. There was, however, a significant decrease in the level of 3.2 kb PAI-I mRNA in placentas from preeclamptic women compared to normal pregnant women. CONCLUSION: To the contrary of our expectation, 3.2 kb PAI-1 mRNA level was significantly lower in placenta from women with preeclampsia compared to normal pregnancy. This seems to reflect differential accumulation of PAI-1 mRNAs due to environmental intluences or decreased differentiation potential of villous trophoblasts to invasive trophoblasts in placenta from preeclamptic women compared to normal pregnant women. The mechanism that regulates plasmin system in human placenta needs further investigations.
Blotting, Northern ; Female ; Fibrinolysin* ; Humans ; Placenta* ; Plasminogen ; Plasminogen Activator Inhibitor 1 ; Plasminogen Activators ; Pre-Eclampsia ; Pregnancy* ; Pregnant Women ; RNA, Messenger ; Trophoblasts