Statement of problem: One of common problems associated with dental implant is the loosening of abutment screws that retain the implants. Purpose: This study was performed to investigate the influence of abutment screw length and repeated tightening on screw loosening in dental implant. Material and method: Forty nine Hexplants (13mm length, 4.3mm diameter, Ti grade IV, Warantec. Co. Ltd. Seongnam, Korea) and cementation type abutments(straight abutment) and abutment screws (0.4mm/pitch) were divided into 7 groups, depending on abutment screw length. Each implant and abutment was tightened to 30Ncm by torque controller(MGT50, MARK-10 Inc., USA) and the removal torque values were measured during 10 consecutive closure/opening trials Results and Conclusion: The results of comparing the removal torque value are as follows: 1. There is no significant difference in the removal torque value between groups in 10 consecutive closure/opening trials(p=0.97). 2. If the fractured abutment screw is engaged in longer than 2.425 thread length, there is no significant difference in the preload between the fractured abutment screw and the new abutment screw when both are equally tightened to 30 Ncm 3. The removal torque value in the 1st trial(24.510 Ncm) was lower than that in the 2nd,3rd,4th,5th,6th,7th trials and the removal torque value in the 2nd trials(25.551 Ncm) was maximum and was decreased in following trials. The removal torque value in the 1st trial was significantly lower than that in the 2nd,3rd,4th trials and was significantly higher than that in the 8th,9th,10th trials(p<0.05). 4. In the 2nd,3rd,4th,5th,6th,7th trials, the abutment screw was mainly influenced by settling effect and the higher preload was obtained. In the 8th,9th,10th trials, the abutment screw was mainly influenced by adhesive wear and the progressively lower preload was obtained.
Adhesives ; Cementation ; Dental Implants* ; Gyeonggi-do ; Torque

About 40% of patients with diabetes mellitus develops to diabetic nephropathy, and these patients show increment of glomerular filtration rate and renal volume at early phase. 99mTc-DMSA SPECT (single photon emission computed tomography) can measure a functional renal volume because 99mTc- DMSA it is taken up by the viable proximal tubular cells located in the renal cortex. To evaluate the renal volume in early diabetic nephropathy, we compared functional renal volume between diabetic patients and control, renal transplantation donor. 99mTc-DMSA was injected intravenously and SPECT was done after 2 hours in 15 diabetic patients, 18 renal transplantation donors, and 2 patients with end stage renal disease due to chronic glomerulonephritis. In diabetic patients with creatinine clearance more than 30ml/min and proteinuria, right and left renal volume were 247+/-22ml/BSA(m2), 256+/-37ml/BSA (m2), which were greater than those of diabetic patients with normal renal function and without proteinuria, or renal transplantation donors(P<0.05). In conclusion, we measured the functional renal volume by 99mTc-DMSA SPECT. Renal volume of diabetic patients with proteinuria were larger than the volume of control group or diabetic patients with normal renal function and without proteinuria. 99mTc-DMSA SPECT was thought to be useful test a for the measurement of functioning renal volume.
Creatinine ; Diabetes Mellitus* ; Diabetic Nephropathies ; Glomerular Filtration Rate ; Glomerulonephritis ; Humans ; Kidney Failure, Chronic ; Kidney Transplantation ; Proteinuria ; Succimer ; Technetium Tc 99m Dimercaptosuccinic Acid* ; Tissue Donors ; Tomography, Emission-Computed, Single-Photon*

PURPOSE: This study aimed to analyze stress distribution and maximum von Mises stress generated in intracoronal restorations and in tooth structures of mandibular molars with various types of cavity designs and materials. MATERIALS AND METHODS: Threedimensional solid models of mandible molar such as O inlay cavity with composite and gold (OR-C, OG-C), MO inlay cavity with composite and gold (MR-C, MG-C), and minimal invasive cavity on occlusal and proximal surfaces (OR-M, MR-M) were designed. To simulate masticatory force, static axial load with total force of 200 N was applied on the tooth at 10 occlusal contact points. A finite element analysis was performed to predict stress distribution generated by occlusal loading. RESULTS: Restorations with minimal cavity design generated significantly lower values of von Mises stress (OR-M model: 26.8 MPa; MR-M model: 72.7 MPa) compared to those with conventional cavity design (341.9 MPa to 397.2 MPa). In tooth structure, magnitudes of maximum von Mises stresses were similar among models with conventional design (372.8 – 412.9 MPa) and models with minimal cavity design (361.1 – 384.4 MPa). CONCLUSION: Minimal invasive models generated smaller maximum von Mises stresses within restorations. Within the enamel, similar maximum von Mises stresses were observed for models with minimal cavity design and those with conventional design.
Bite Force ; Dental Enamel ; Finite Element Analysis ; Inlays ; Mandible ; Molar ; Tooth

The p53 oncoprotein, a product of the tumor suppressor gene encoded on the short arm of chromosome 17, has been noted in a number of human tumors as a tumor suppressor and some what has been related with cellular apoptosis. Thus, mutant p53 inhibits apoptosis. Like the mutant p53 oncoprotein, the bcl-2 oncoprotein expressed in various epithelial and nonepithelial cells plays a major role in inhibiting cellular apoptosis. To elucidate the role of bcl-2 and mutant p53 oncoprotein expression in gastric adenocarcinomas, immunohistochemical stains were carried out in 60 cases of gastric adenocarcinomas including 10 cases of early gastric cancer. We studied the expression patterns of the bcl-2 and the mutant p53 protein according to age, sex, histologic differentiation, tumor location, tumor size, lymph-node involvement, and depth of tumor invasion. The results were as follows: 1) p53 protein expression was detected in 39 of 60 cases (65%), and bcl-2 protein expression was detected in 29 of 60 cases (48%). 2) The p53 and the bcl-2 expression rates for early gastric cancer were 60% and 50%, and those for advanced gastric cancer were 66% and 40%, respectively. 3) There was no significant correlation of p53 or bcl-2 expression with sex, age, histologic differentiation, tumor location, tumor size, and lymph-node involvement; however, the expression of p53 was correlated with the depth of tumor invasion (p=0.049). Based on the present study, the expression of p53 is thought to be correlated with tumor progression and may be a useful prognostic factor in gastric adenocarcinomas.
Adenocarcinoma* ; Apoptosis ; Arm ; Chromosomes, Human, Pair 17 ; Coloring Agents ; Genes, bcl-2* ; Genes, p53* ; Genes, Tumor Suppressor ; Humans ; Immunohistochemistry ; Stomach Neoplasms

PURPOSE: This study aims to analyze the stress distribution of mandibular molar restoration supported by the implants with external hex and internal taper abutment connection design. MATERIALS AND METHODS: Models of external connection (EXHEX) and internal connection (INCON) implants, corresponding abutment/crowns, and screws were developed. Supporting edentulous mandibular bony structures were designed. All the components were assembled and a finite element analysis was performed to predict the magnitude and pattern of stresses generated by occlusal loading. A total of 120 N static force was applied both by axial (L1) and oblique (L2) direction. RESULTS: Peak von Mises stresses produced in the implants by L2 load produced 6 – 15 times greater than those by L1 load. The INCON model showed 2.2 times greater total amount of crown cusp deflection than the EXHEX model. Fastening screw in EXHEX model and upside margin of implant fixture in INCON model generated the peak von Mises stresses by oblique occlusal force. EXHEX model and INCON model showed the similar opening gap between abutment and fixture, but intimate sealing inside the contact interface was maintained in INCON model. CONCLUSION: Oblique force produced grater magnitudes of deflection and stress than those by axial force. The maximum stress area at the implant was different between the INCON and EXHEX models.
Bite Force ; Crowns ; Finite Element Analysis* ; Molar

Measurements were made of the residual level of chlorinated hydrocarbon compound and mercury compound in the tissues of wild birds and herbs in Korea from November 1974 to August 1975. Aldrin was detected in all of the wild birds analyzed. The residue levels of aldrin varied from 0.353ppm to 16.115ppm. Among the tissues analyzed, the feathers contained the highest concentration of aldrin, but chloridane could not be detected in wild birds. The pesticides detected in wild birds were (alpha+beta)-BHC gamma-BHC, delta-BHC, heptachlor, aldrin, TDE and DDT. Dieldrin was detected only in the stomach of eastern dunlin caught at the Nakdong River basin. Residue levels of mercury were measured in all wild birds analyzed. Among tissues analyzed for mercury compound concentration, here also the feathers showed the highest level. The feathers of the eastern dunlin showed a high content of mercury compound which was 76.665 ppm at the highest level. Herbs used as material for oriental remedies were contaminated by chlorinated hydrocarbons which were (alpha+beta)-BHC, gamma-BHC, dieldrin, DDT, heptachlor, TDE, aldrin and epoxide. The insect materials from Cicadae testa, Bombycis corpus, and Scolopendia were much more contaminated by pesticides than plant materials. Herbs cultivated in arable areas were also found to be more contaminated by pesticides than wild ones. Herbs, on the whole, contained lower levels of chlorinated hydrocarbons than wild birds. The incidence of pesticide residues in natural products and in wild birds, however, should be considered as a global environmental pollution problem. The present investigation could contribute as a baseline study for the monitoring of pesticide pollution, its application and dispersal, and the hazard limit for food and human health.
Animal ; Birds/metabolism* ; Human ; Hydrocarbons, Chlorinated/analysis ; Korea ; Mercury/analysis ; Pesticide Residues/analysis* ; Plants/analysis*

Mycobacterium chelonae is a rapidly growing organism that has been found in water, soil, and dust. Although it can colonize healthy persons without sequelae, it can also cause skin and soft tissue infections, pulmonary infections and other sequelaes and rarely, disseminated disease in immunocompromised patients. But, infections due to rapidly growing mycobacteria are probably markedly underdiagnosed and these organisms are capable of causing a wide spectrum of clinical disease. We experienced a case of wound infection with M. chelonae after percutaneous endoscopic gastrostomy and report with review of literatures.
Colon ; Dust ; Gastrostomy* ; Humans ; Immunocompromised Host ; Mycobacterium chelonae* ; Mycobacterium* ; Skin ; Soft Tissue Infections ; Soil ; Wound Infection* ; Wounds and Injuries*

No abstract available.
Asian Continental Ancestry Group* ; Humans

OBJECTIVE: Unilateral percutaneous vertebroplasty is a widely accepted treatment for osteoporotic vertebral compression fractures (VCFs). However, bone cement may fail to fill both hemivertebra from the single needle. We assessed the radiographic and clinical outcome of hemivertebroplasty (HVP) and evaluated the factors that affect subsequent VCFs after HVP. METHODS: Fifty two patients who underwent HVP were reviewed. VCFs were identified based on clinical and radiological findings. The patients were grouped into two groups: 1) no subsequent VCFs, 2) subsequent VCFs. We evaluated the association between age, sex, body mass index (BMI) and bone mineral density (BMD) and subsequent VCFs. We also assessed the impact of location, type and grade of fracture, endplate fracture, burst fracture, bone cement volume on subsequent VCFs. We analyzed the compression ratio, wedge angle, kyphotic angle, and visual analogue scale (VAS) score in both groups. RESULTS: There were no significant differences in age, gender, BMI, and BMD between two groups. No significant difference was also found in pre-existing VCF, location, type and grading of fracture, endplate fracture, burst fracture, amount of bone cement, and radiological findings such as compression ratio, wedge angle, and kyphotic angle between two groups. The final mean VAS scores of patients with or without subsequent VCFs were 3.11 and 4.02, respectively. CONCLUSION: No major risk factors for the subsequent VCFs after HVP were found. However, we identified adjacent fractures, refractures, and remote fractures after HVP in chronological order. Therefore, long-term follow-up is necessary to evaluate the effectiveness of HVP to osteoporotic VCFs.
Body Mass Index ; Bone Density ; Follow-Up Studies ; Fractures, Bone ; Fractures, Compression ; Humans ; Needles ; Osteoporotic Fractures ; Risk Factors ; Vertebroplasty

OBJECTIVES: Bisphenol A Di Glycidyl Ether (BADGE) is the major component in commercial liquid epoxy resins, which are manufactured by co-reacting bisphenol A with epichlorohydrin. The authors investigated the acute toxicity of BADGE. METHODS: BADGE was administered by a gavage to 8 week old SPF Sprague Dawley rats in a single dose of 0 (negative control), 0.37 (Diethylstilbesterol, DES), 1000, 2000, 4000, and 8000 mg/kg/day of BADGE. Each treatment group contained 7 rats. The general status and weight of the rats were observed for 14 days. The rats were anesthetized by ether at 14 days, and the changes in morphology, organ weight, sperm count and motility, and hormone level were measured. RESULTS: All the rats treated with BADGE had diarrhea on the 1st day. The rats administered BADGE at 1000, 2000, and 4000 mg/kg/day showed a soiled perineal region and soft stools with diarrhea until the 3rd day. The 8000 mg/kg/day BADGE rats had diarrhea for two days followed by emaciation, soiled fur, a soiled perineal region, staining around the mouth and were moribund for three to eight days. No weight gain was observed after the 1st day in the 2000, 4000, and 8000 mg/kg/day BADGE rats and after the 7th day in all the treatment groups compared with the control groups. Some treatment groups were observed to have a decrease in the weight of the heart (BADGE 1000, 2000 and 4000 mg/kg/day), liver (BADGE 1000, 2000, 4000 and 8000 mg/kg/day) and prostate (BADGE 4000 mg/kg/day) compared with control group. The weight of the liver was significantly lower in all treatment groups compared with the control group. The relative weight of the liver (BADGE 1000 and 4000 mg/kg/day) was significant lower than the control. No pathological changes were observed in the brain, liver, thyroid, heart, spleen, kidney, lung and prostate. The number of spermatid in the seminiferous tubule in the testes was lower in all treatment groups than the control. The sperm motility tended to decrease with increasing concentration but the sperm count was similar in all treatment groups. The plasma Estrogen and testosterone level were similar in the control and treatment groups. CONCLUSIONS: These results suggest that BADGE induces general, hepatic and reproductive toxicity at 1000 mg/kg/day.
Animals ; Brain ; Diarrhea ; Emaciation ; Epichlorohydrin ; Epoxy Resins ; Estrogens ; Ether* ; Heart ; Humans ; Kidney ; Liver ; Lung ; Male* ; Mouth ; Organ Size ; Plasma ; Prostate ; Rats ; Rats, Sprague-Dawley* ; Seminiferous Tubules ; Soil ; Sperm Count ; Sperm Motility ; Spermatids ; Spleen ; Testis ; Testosterone ; Thyroid Gland ; Weight Gain