1.STRESS OF DENTAL IMPLANT ABUTMENT SCREW BY THE TIGHTENING TORQUE.
Won Joo LEE ; Ju Hwan LIM ; In Ho CHO
The Journal of Korean Academy of Prosthodontics 1998;36(5):721-737
Abutment screw loosening of implant restorations is a common problem in the treatment of dental implant. The purpose of this study was to calculate stress and preload from the elongation measurements and to determine maximum tightening torque without plastic deformation of the screw. The length of each gold alloy UCLA screw was measured after tightening to the manufacturer's recommended torque of 32 N-cm. Similarily, titanium UCLA screws were measured after tightening to the manufacturer's recommended torque of 20 N-cm. Loosening torque was also measured after tightening to 32 N-cm torque for gold alloy abutment screws and 20 N-cm for titanium abutment screws. The results were as follows ; 1. There was a regressive relationship between screw elongation and tightening torque (gold alloy : r2 = 0.987, titanium : r2 = 0.978), and the mean preload calculated from elongation measurements was 501.11 +/- 26.85 N (gold alloy) and 399.43 +/- 7.61 N (titanium). 2. Stress calculated for the gold alloy and titanium screws at maximum recommended tightening torque was less than 60% of their respective yield strengths and within the elastic range. Maximum tightening torque without plastic deformation was 61 N-cm(gold alloy) and 39 N-cm(titanium). 3. For titanium screws, there was a significant difference between loosening after trial 1 and loosening after trials 2 to 5 (p<0.05). No statistically significant difference was seen in mean loosening torques between the first and subsequent trials for gold alloy screws.
Alloys
;
Dental Implants*
;
Plastics
;
Titanium
;
Torque*
2.Creutzfeldt-Jakob Disease: Histopathologic, Electron Microscopic and Immunohistochemical Studies of 2 Cases.
Duck Hwan KIM ; Yeon Lim SUH ; Duck Ryul NA ; Won Kyu JOO ; Yong Sun KIM
Korean Journal of Pathology 1996;30(9):830-838
Creutzfeldt-Jakob disease(CJD) is characterized clinically by rapidly progressive dementia with pyramidal, extrapyramidal, and cerebellar symptoms and signs, and histologically by spongiform change, neuronal loss and reactive gliosis. We have experienced 2 cases of CJD. Case 1 was a 36-year-old male who had suffered from myoclonus and cerebellar symptoms including sluggish speech, gait and balance disturbance. Case 2 was a 70-year-old female who had showed cognitive dysfunction, ataxic gait and disturbance of extraocular movement. Both patients, underwent brain biopsy. Case 1 revealed marked cortical atrophy, 2mm in thickness, with neuronal loss and astrocytic proliferation extending into white matter. The spongiform change, made up of many small, usually rounded or oval, vacuoles was noted mainly in the neuropil. Case 2 revealed remarkable spongiform change throughout the cortex and cytoplasmic vacuoles compressing the nuclei of neuronal cells were numerous. Neuronal loss and gliosis were also found without considerable change in the white matter. On double immunostaining against GFAP and PrP(Prion Protein), there was a weak positive reaction for PrP in the perinuclear cytoplasm in case 1, and a strongly positive reaction in case 2. The electron microscopic examination showed numerous membrane-bound vacuoles in neuropil and perikarya of neurons. The majority of the vacuoles were multiseptated by thin membranous structures. They demonstrated curled, or disrupted membrane, that had foldings and protrusions into the vacuolar clear spaces. There were neither identifiable virus-like particles nor amyloid deposition.
Female
;
Male
;
Humans
3.A Case of Kasabach-Merritt Syndrome with Disseminated Intravascular Coagulopathy Treated with Interferon alfa-2a.
Seok Gang YUN ; Pan Joo LIM ; Seong Hwan BAN ; Dong Hwan LEE
Journal of the Korean Society of Neonatology 2000;7(1):72-75
We have recently encountered a case of Kasabach-Merritt syndrome which was characterized by hemangioma, thrombocytopenia, and Disseminated Intravascular Coagulation. The baby was delivered at 35 weeks gestation. A large hemangioma covered right forearm. He received interferon alfa-2a for 120 days after 20 day steroid treatment failure. Blood platelet count increased to acceptable range (>20,000/mm3) after 8weeks of interferon alfa-2alpha treatment and the size of hemangioma decreased.
Disseminated Intravascular Coagulation
;
Forearm
;
Hemangioma
;
Interferons*
;
Kasabach-Merritt Syndrome*
;
Platelet Count
;
Pregnancy
;
Thrombocytopenia
;
Treatment Failure
4.Inspection of Blood Collection Center with Small Number of Unit Collection.
Hwan Sub LIM ; Chae Seung LIM ; Young Joo CHA ; Yoon Young CHOI ; Young Ae LIM ; Jang Soo SUH
Korean Journal of Blood Transfusion 2009;20(3):195-200
BACKGROUND: Transfusion is a choice of treatment and should be used in order to maintain patients' lives and health. In order to supply safe blood, the quality improvements of hospital blood collection centers should be periodically monitored. To establish systematic surveillance of blood management system, we would like to suggest proper program. METHODS: Twenty-nine hospital small scale blood centers, collects less than 100 units of blood collection per year, were evaluated. Qualified were selected among blood bank specialists who were eligible to simultaneously perform inspections and consultations, and who had attended inspectors' workshop. RESULTS: Among twenty-five blood collection centers, four blood collection centers were closed prior to inspections. Among them, two blood collection centers were evaluated as inadequate. Among adequate centers, some questionnaires were evaluated as "not applicable" mainly for reasons pertaining to personnel and facilities, such as blood component preparation rooms and/or center administrators. CONCLUSION: A checklist for an inspection program should be reviewed continuously. Additionally, detailed guidelines for inspection should be standardized prior to commencing of subsequent year's inspection program. Finally, guidelines for inspection should be established for every questionnaire.
Blood Banks
;
Checklist
;
Quality Improvement
;
Referral and Consultation
;
Specialization
;
Surveys and Questionnaires
5.The Range of Ocular Torsion in Mass Screening.
Journal of the Korean Ophthalmological Society 2005;46(10):1684-1689
PURPOSE: To determine the range of cyclotorsion in the mass screening of patients by studying the spatial relationship between the optic disc and the fovea. METHODS: We examined the horizontal and vertical distances from the center of the optic disc to the fovea using the fundus photographs of 249 subjects (498 eyes) without a past history of strabismus through mass screening and then calculated the optic disc-foveal angle. We studied the differences in all the measured parameters between the right and left eyes and between men and women. RESULTS: The horizontal distance from the center of the optic disc to the fovea was 2.59+/-0.26 DD (disc diameter) in the right eye and 2.58+/-0.27 DD in the left eye. The mean horizontal distance was 2.59+/-0.26 DD. The vertical distance from the center of the optic disc to the fovea was 0.28+/-0.14 DD in the right eye and 0.30+/-0.13 DD in the left eye. The mean vertical distance was 0.29+/-0.14 DD. The calculated disc-foveal angle was 6.26+/-2.98 degrees in the right eye and 6.69+/-2.84 degrees in the left eye (mean, 6.50+/-2.92 degrees). There were no significant differences between the right and left eyes or between males and females. The 95% range of the location of the fovea was from 0.01 DD to 0.57 DD inferior to the optic disc center. CONCLUSIONS: We concluded that the clinical location of the fovea, as measured in the mass screening, extends from the center of the optic disc to the lower edge of the optic disc.
Female
;
Humans
;
Male
;
Mass Screening*
;
Strabismus
6.Changes of Higher Order Aberration Analyzed by Continuous Measurement after Phacoemulsification.
Hyung Bin LIM ; Jong Joo LEE ; Si Hwan CHOI
Journal of the Korean Ophthalmological Society 2015;56(1):25-32
PURPOSE: To analyze the changes of higher order aberration (HOA) measured serially by KR-1W(R) wavefront at every second for 10 seconds between, before, and after phacoemulsification and to evaluate the relationships between HOA and the ocular surface indicators (Schirmer test, tear break-up time, superficial punctate keratitis). METHODS: Corneal HOA was measured in 47 eyes of 30 patients pre- and postoperatively at 2, 4, 6, and 8 weeks by KR-1W(R) using the continuous measurement mode. The patients were divided into 2 groups according to their Schirmer test (above 10 mm or under 10 mm), tear break-up time (above 5 seconds or less than 5 seconds), and superficial punctate keratitis (any keratitis, none) for analysis of relationships between HOA and ocular surface indicators, and we also analyzed the correlation coefficient. RESULTS: Short-term follow up after phacoemulsification revealed that corneal HOA rapidly increased at 2 weeks and recovered to the preoperative level 8 weeks after surgery. Corneal HOA values showed increasing tendency depending on time at preop and 8 weeks after phacoemulsification, and the differences were statistically significant (preop: p < 0.001, 8 weeks: p = 0.027). There were no significant differences of HOA between the 2 groups divided according to their ocular surface indicators, and there were no significant correlations between HOA and ocular surface indicators at any time point. CONCLUSIONS: The HOA of the cornea was restored to its preoperative values at 8 weeks after surgery. Preoperative ocular surface indicators are not significantly influenced on postoperative corneal HOA. The surgical factors are more significant in postoperative corneal HOA than preoperative ocular surface indicators.
Cornea
;
Follow-Up Studies
;
Humans
;
Keratitis
;
Phacoemulsification*
;
Tears
7.Clinical Characteristics of the Patients Referred to Ophthalmic Clinic for Medical Disability Evaluation.
Hyun Jin KIM ; Hyun Joo LEE ; Key Hwan LIM
Journal of the Korean Ophthalmological Society 2008;49(5):819-824
PURPOSE: To investigate the clinical characteristics and disability rates of patients seeking expert consultation for legal reasons because of ophthalmologic symptoms. METHODS: We analyzed the gender, age, reason for consultation, and result of consultation, among other factors, by retrospectively examining the medical files of 89 patients from January 1999 to December 2004. RESULTS: Out of 89 patients, men constituted 76.4% and patients in their forties constituted 23.0%. The most common reason for consultation was a traffic accident (64.0%), followed by a medical lawsuit (11.2%). Forty-nine patients (55.1%) were diagnosed with a disability, while 30 patients (33.7%) were not. Diagnostic decisions for the other 10 patients (11.2%) were deferred. Optic atrophy was the most frequent cause for deteriorating visual acuity in patients, accounting for 19 cases, and diplopia caused by orbital wall fracture was also prevalent (9 patients). Among the resulting types of damage, brain damage was the most frequent, while the percentage of patients with an impairment in the visual system was approximately 29.0% among the patients diagnosed with a disability. CONCLUSIONS: Our results will be helpful in elucidating the clinical characteristics of patients referred to the ophthalmic clinic for consultation because of legal concerns.
Accidents, Traffic
;
Accounting
;
Brain
;
Diplopia
;
Disability Evaluation
;
Humans
;
Male
;
Optic Atrophy
;
Orbit
;
Retrospective Studies
;
Visual Acuity
8.A study on the vertical augmentation of the alveolar ridge by distraction osteogenesis in dogs.
Joo Ho LEE ; Ju Hwan LIM ; In Ho CHO
The Journal of Korean Academy of Prosthodontics 2007;45(1):107-118
STATEMENT OF PROBLEM: Implant-type distractor uses a removable distraction device that has an appearance similar to that of a dental implant and utilizes many of the same techniques for placement as are used for dental implants. MATERIAL AND METHOD: In this study, 48 implant type titanium distractors were inserted into the osteotomized alveolar bone of 12 beagle dogs. After a 7-day latency period, the alveolar bone was augmented by 5mm vertically at a rate of 1.0 mm/day. The dogs were sacrificed after 4weeks, 8weeks and 12 weeks for radiographic, histologic, and histomorphometric analysis. RESULTS: Copper equivalent value showed significant difference between 4 weeks and the other weeks(8, 12 weeks)(p<0.05). But there was no significant difference between maxillary and mandibular groups. In the bone to metal contact analysis, there was a significant difference between 4 weeks and 12 weeks(p<0.05). On the contrary, there was no significant difference between maxilla and mandible. The bone area showed significantly higher values in 12 weeks compared to 4 weeks(p<0.05). Histologically mineralization began at the host bone margins. At 12 weeks, increasing accumulation of Ca++ element was confirmed. CONCLUSION: From the results above, the new bone formation was increased according to consolidation period. Especially there was significant difference between 4 weeks and 12 weeks(p<0.05). Implant type distractors used in this study to augment vertical ridge defect may prove to be a clinically useful treatment option in selected cases.
Alveolar Process*
;
Animals
;
Copper
;
Dental Implants
;
Dogs*
;
Latency Period (Psychology)
;
Mandible
;
Maxilla
;
Osteogenesis
;
Osteogenesis, Distraction*
;
Titanium
9.Multiple Primary Colorectal Cancer.
Yong Seok LIM ; Seok Hwan LEE ; Sung Wha HONG ; Choong YOON ; Hoong Zae JOO ; Kee Hyung LEE
Journal of the Korean Society of Coloproctology 1998;14(1):27-34
To assess the clinico-pathological characteristics of patients with multiple primary colorectal cancer, 458 patients who underwent curative surgery and being followed-up at our institution between Jan. 1987 and Dec. 1993 were evaluated in this study. The median follow-up period was 42 months. Synchronous cancer was defined as distinct lesions separated by a distance of greater than 4cm with the invasion of the tumor below the muscularis mucosa at the time of diagnosis or within 6 months after initial treatment, and metachronous cancer was defined as the development of colon cancers more than 6 months after the initial treatment without evidence of the recurrence or metastases from primary tumor. There were 29 cases of multiple primary colorectal cancer(6.3%). Eighteen cases(3.9%) of them were synchronous, 11 cases(2.4%) were metachronous cancers. Seven cases(1.5%) were related to 5 hereditary non-polyposis colorectal cancer(HNPCC) families. During the follow-up period, 11 patients(2.4%) developed cancers in other organs. Adenomatous polyps were identified 14 cases of 29 patients with multiple primary colorectal cancers(48.3%), compared to 43 cases(10%) in 429 patients with solitary colorectal cancer(p<0.01). After initial curative surgery, there were 8 recurrences in 29 patients with multiple primary colorectal cancers(23.6%), compared to 100 recurrences in 429 patients with solitary primary colorectal cancer(23.3%)(p>0.05). In aspect of family history, there was close-relationship with this regarding in the group of multiple primary colorectal cancers. However, authors were unable to make analysis this regarding in the group of solitary primaries because of lack of the information. Conclusively, authors guess the frequent association of the adenomatous polyps in multiple primary colorectal cancers as the evidence of the adenoma-carcinoma sequence. In addition, authors emphasized the importance of the total colonoscopic examinations in pre-and post-operation in order to make diagnosis of the multiple primary colorectal cancers and paying attention as to the family history of colorectal cancer patients because we have good therapeutic results after operation of early stage in synchronous cancers and co-existent adenomatous polyps.
Adenomatous Polyps
;
Colonic Neoplasms
;
Colorectal Neoplasms*
;
Diagnosis
;
Follow-Up Studies
;
Humans
;
Mucous Membrane
;
Neoplasm Metastasis
;
Recurrence
10.Second Primary Cancer after Diagnosis and Treatment of Cervical Cancer.
Myong Cheol LIM ; Young Joo WON ; Jiwon LIM ; Yeon Joo KIM ; Sang Soo SEO ; Sokbom KANG ; Eun Sook LEE ; Jae Hwan OH ; Joo Young KIM ; Sang Yoon PARK
Cancer Research and Treatment 2016;48(2):641-649
PURPOSE: This study was conducted to investigate the incidence and survival outcomes of second primary cancers after the diagnosis of cervical cancer. MATERIALS AND METHODS: Data from the Korea Central Cancer Registry between 1993 and 2010 were reviewed and analyzed. Standardized incidence ratios (SIRs) of second primary cancers among women with cervical cancer were analyzed. Kaplan-Meier survival curves were constructed for cervical cancer patients with or without a second primary cancer. RESULTS: Among 72,805 women with cervical cancer, 2,678 (3.68%) developed a second primary cancer within a mean follow-up period of 7.34 years. The overall SIR for a second cancer was 1.08 (95% confidence interval, 1.04 to 1.12). The most frequent sites of second primary cancers were the vagina, bone and joints, vulva, anus, bladder, lung and bronchus, corpus uteri, and esophagus. However, the incidence rates of four second primary cancers (breast, rectum, liver, and brain) were decreased. The 5-year and 10-year overall survival rates were 78.3% and 72.7% in all women with cervical cancer, and for women with a second primary cancer, these rates were 83.2% and 65.5% from the onset of cervical cancer and 54.9% and 46.7% from the onset of the second primary cancer, respectively. CONCLUSION: The incidence rates of second primary cancers were increased in women with cervical cancer compared to the general population, with the exception of four decreasing cancers. The 10-year overall survival rates were decreased in cervical cancer patients with a second primary cancer.
Anal Canal
;
Bronchi
;
Cervix Uteri
;
Diagnosis*
;
Esophagus
;
Female
;
Follow-Up Studies
;
Humans
;
Incidence
;
Joints
;
Kaplan-Meier Estimate
;
Korea
;
Liver
;
Lung
;
Neoplasms, Second Primary*
;
Rectum
;
Survival Rate
;
Urinary Bladder
;
Uterine Cervical Neoplasms*
;
Uterus
;
Vagina
;
Vulva