Purpose : This research evaluates the effect of the use of absorbable membrane barrier with deproteinized bovine bone (Bio-$Oss^{(R)}$, Switzerland) on bone healing in surgically created critical-sized defects in rat calvaria. Materials and Methods : Two standardized transosseous circular calvarial defects (5 mm in diameter) are made in each calvarium of 30 rats. These rats are divided into negative control group(n=15), positive control group(n=15) and two experimental groups(n=15). In the negative control group, defects are only filled with blood clots. In the positive control group, defects are filled with autogenous bone obtained from calvarium; in the experimental group 1, defects are filled with deproteinized bovine bone; and in the experimental group 2, defects are filled with deproteinized bovine bone with absorbable membrane. At the postoperative 1 week, 3 weeks. and 6 weeks, clinical. histologic and histomorphometric evaluations of the defects are performed. Results : 1. The grafted bone without membrane in the calvarial bone defect was scattered but, the grafted bone with membrane was stable. 2. $BioMesh^{(R)}$ membrane was absorbed beginning at 3 weeks, and was absorbed considerably at 6 weeks while maintaining the structural form of the membrane. 3. The use of membrane blocked soft tissue invasion. 4. In histomorphometric analysis. it showed the greatest amount of new bone formation in the positive control group. The amount of new bone formation was greater in the experimental group 2 than experimental group 1. At 6 weeks. the amount of new bone formation was greater in the positive control group than experimental group l(p<0.005). Conclusion : These results suggest that membrane increase the stability of grafted bone and protects from soft tissue invasion, and the use of the membrane may promote new bone formation in deproteinized bovine bone graft area.
While orofacial pain or various dental factors are generally considered as the primary cause of unilateral chewing tendency, there exist several studies indicating that dental factors did not affect the preferred chewing side. The aim of this study was to examine difference of occlusal scheme between the subjects with and without chewing side preference. The difference between the chewing and non-chewing sides in the unilateral chewing group was investigated as well. Computerized, T-Scan II system was used for occlusal analysis. 20 subjects for the unilateral chewing group (mean age of $25.25{\pm}2.84$ years) and 20 subjects for the bilateral chewing group (mean age of $27.00{\pm}5.07$ years) were selected by a questionnaire on presence or absence of chewing side preference and those with occlusal problem or pain and/or dysfunction of jaw were excluded. T-Scan recordings were obtained during maximum intercuspation and excursion movement. The number of contact points, relative occlusal force ratio between right and left sides, tooth sliding area and elapsed time throughout the maximum intercuspation were calculated. Elapsed time for excursion was also investigated. The results of this study shows that the unilateral chewing group had the smaller average tooth contact areas compared with those of the bilateral group (p<0.005). In the unilateral chewing group, the contact areas of non-chewing side are smaller than those of chewing side (p<0.005). The contact areas on their preferred sides were not significantly different with those of right or left side of the subjects without chewing side preference. There was no significant difference in the elapsed time during maximum intercuspation and lateral excursion, the sliding areas and relative of right-to-left occlusal force ratio between the two groups. From the results of this study, it is likely that individuals prefer chewing on the side with more contact areas for efficient chewing.
Statement of problem: There are common clinical cases in which the mandibular first and second molars are missing unilaterally. Purpose: This study was designed to compare and evaluate the magnitude and distribution of stress produced by four kinds of mandibular unilateral free-end removable partial dentures that could be applied clinically in Kennedy class II cases. Material and methods: Four unilateral free-end removable partial dentures using clasp, Konus crown, resilient attachment, and flexible resin were fabricated on the photoelastic models of the Kennedy class II cases. The vertical load of 6㎏ was applied on the central fossa of the first molar of every removable partial denture in the stress freezing furnace and the photoelastic models were frozen according to the stress freezing cycle. After these models were sliced mesio-distally to a thickness of 6mm, the photoelastic isochromatic white and black lines of the sliced specimens were examined with the transparent photoelastic experiment device and photographs were taken with a digital camera. The fringe order numbers at eight measuring points in the photograph were measured with the naked eye. Results: The maximum fringe order number of each sliced specimen and the fringe order number at the residual ridge just below the loading point were in the decreasing order of the unilateral removable partial dentures using flexible resin followed by clasp, resilient attachment, and Konus crown. The fringe order number at the root apex of the second premolar was in the decreasing order of the unilateral removable partial dentures using clasp followed by flexible resin, Konus crown, and resilient attachment. Conclusion: The removable partial denture using Konus crown showed the most equalized stress distribution to the supporting alveolar bone of abutment teeth and residual ridge under the vertical loads. The removable partial denture using flexible resin can be applied to the case that has a better state of residual ridge than abutment teeth.
Statement of problem: Restoring and replacing teeth with fixed prostheses commonly used in dental practice. Because of improper oral hygiene care and inaccurate laboratory procedure, complications of fixed prostheses were found in the mouth of patients. Although many efforts have been continually made to obtain the data of long term prognosis of fixed prostheses, it was difficult to do it. Purpose: The purpose of this study was to evaluate the clinical status of fixed prostheses. Material and methods: In order to assess the clinical status of fixed prostheses, a total of 161 individuals(aged 17-85, 99 women and 62 men with 1596 unit of fixed prostheses, and 1169 abutments) who first visited the Department of Prosthodontics, Pusan National University Hospital, between April to September, in 2007 were examined. Results and conclusion: The results of this study were as follows: 1. Length of service of fixed prostheses was $8.6{\pm}0.6$ years(mean), 10.0 years(median). 2. Location of fixed prostheses was found to have no statistically significant influence on longevity of fixed prostheses(P>.05). But, the success rate was high in posterior region and in mandible where the failure rate was high in combination(P<.05). 3. Longevity of fixed prostheses made of metal was longest(mean: $13.0{\pm}9.3$, median: 14.0), gold, precious ceramic, non-precious ceramic trailing behind(P<.05). 4. Number of units in fixed prostheses was found to have no statistically significant influence on longevity of fixed prostheses(P>.05). But, the success rate was high in Single-unit and the failure rate was high in over 3-unit(P<.05). 5. Condition of opposing dentition was found to have no statistically significant influence on longevity of fixed prostheses(P>.05). But, the success rate was high in natural dentition(P<.05). 6. Defective margin(28.2%), dental caries(23.0%), periodontal disease(19.3%), periapical disease(16.9%) were frequent complications. In 30.1% of the cases, abutment state after removing fixed prostheses was needed to be extracted.
In order to improve some problems such as contamination of undesirable mold, mycotoxin production and excessive drying on the surface of traditional meju, we developed a capsule type-meju(CM) coated with steamed black bean and Aspergillus oryzae - rice koji(0.3%, w/w) mixture to surface of traditional meju and fermented at 25$^{\circ}C$ for 14 days under 80% relative humidity. Contamination of undesirable mold on the surface of CM was not detected within 2 weeks and some genus Penicillium molds on control meju without koji were found naturally after 12 days of fermentation. The moisture content of meju was showed to be in the range of 34.7 - 29.4% being 32.7%(w/w) of mean value. Titratable acidities in CMs prepared with black bean(BCM) and soybean(SCM) were much higher than that in control meju, and BCM was similar to SCM. Free sugar content in BCM(123.98 mg%) was 10 times and 2.1 times higher than that in control meju(15.02 mg%) and SCM(59.85 mg%), respectively. Amino type nitrogen content in control meju was 147.00 mg% and its content in BCM(255.50 mg%) was 1.37 times higher than that in SCM(187.25 mg%). Total organic acid content in BCM(95.98 mg%) and SCM(1l9.98 mg%) were much higher than that in control meju(26.44 mg%), and then lactic and malic acid contents were markedly changed according to capsulation of meju. Lightness value(L) of Hunter color index was much higher in BCM than in SCM. Fatty acid composition of CM was not different as compared to control meju. Total free amino acid content in BCM(1039.70 mg%) was 4.4 times and 2.4 times higher than that in control meju(236.45 mg%) and SCM(556.07 mg%), respectively.
Cardiopulmonary bypass in children is associated with capillary leak which results in an increase in total body water after open heart surgery The purpose of these studies was to assess the cardiopulmonary effects of modified ultrafiltration after pediatric open heart surgery Study h: Twenty-six consecutive children aged 0.1 ~ 10 years(median 7 months) underwent cardiac operation inc rporating modified ultrafiltration. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at the flow rate of 100~ 15011min for 3 ~ 14 min. After modified ultrafiltration, elevation of hematocrit(28.3% $\pm$ 3.6% vs. 33.8olo $\pm$ 4.Ooloi p < 0.001), increased systolic 1)loots Pressure(66.7 $\pm$ 11.2mmHg vs. 76.2$\pm$ 11.BmmHg, p < 0.02), and decreased central venous pressure(7.8 $\pm$ 3.7mmHg vs. 6.9$\pm$ 2.gmmHg, p<0.001) were observed. Study B: Twenty-six children who underwent cardiac operation with the diagnosis of VSD under 2 years were assigned to control(n= 14) or modified ultrafiltration(n= 12). Peak inspiratory pressure checked immediately after operation was significantly lower in modified ultrafiltration group than in control group(20.0$\pm$ 2.4 cmH20 vs.22.4$\pm$ 2.3cmH20, p < 0.03). Modified ultrafiltration after cardiopillmonary bypass in children improves early homodynamics and pulmonary mechanics, and represents an excellent option for perioperative managemen of accumulation of fluid in the tissues. We will continually employ the modified ultrafiltration technique in pediatric cardiac operations.
Clinical analysis of the relation between the clinical data of chest trauma patients and bone scan results was done to investigate the sensitivity and specificity of bone scan for the diagnosis of rib or chondral fracture. Material and Method: 445 patients treated due to chest trauma in Dongguk University Kyungju Hospital from July 1998 to December 2001 were studied. Age and sex distribution, causes of chest trauma, interval from the injury to arrival at hospital, final diagnosis, relationship between the chest pain and bone scan results, relationship between local tenderness and bone scan results, and sensitivity and specificity of bone scan were studied. Result: The male was 61.6% and the female was 38.4%. Age distribution was nearly even from the twenties to the sixties. The traffic accident was the most common cause of chest injury(60.4%). Most patients(76.6%) were arrived to the hospital within 6 hours after chest trauma. Rib fracture was the most common final diagnosis(46.5 %). The relationship between the duration of chest pain and tenderness and the bone scan results were significant, and the same in the relationship between the duration of local tenderness and the bone scan results, but the latter is more significant. The sensitivity of bone scan was 99.4% and the specificity was 90.4%. Conclusion: If the patient complains the chest pain continuously and the local tenderness around the chest is continued over 3 weeks, it is good to perform the bone scan. Further study including the MRI may be helpful for more evaluation in chest trauma patients.
To investigate the role of bkdR, sigL, yplP, and des genes which were known to be involved in fatty acid synthesis and sensitive at low temperature, deletion mutants of Bacillus subtilis CU1065 and JH642 were constructed. To determine the low temperature sensitivity of these genes, we compared the growth curves of cells at $37^{\circ}C$ and $15^{\circ}C$. At $37^{\circ}C$, wild type and deletion mutants showed almost similar growth but only bkdR deletion strain at $15^{\circ}C$ showed very slow growing compared with wild type. At $15^{\circ}C$ sigL and yplP deletions were somewhat slower or similar to those of wild type strain. Double and triple mutants for bkdR, sigL, yplP deletions were constructed and grown at $20^{\circ}C$ in LB agar to investigate cold sensitive growth. Double or triple deletions including bkdR deletion showed cold sensitive growing. In order to identify more clearly cold sensitive growth, the experiments were carried out under cold shock conditions in which the temperature was lowered from $37^{\circ}C$ to $15^{\circ}C$ at the point of 0.4 optical densities at 600 nm. In these cold shock experiments, only bkdR deletion showed significantly lower growing and additional des deletion increases cold sensitivity. The bkdR activates the bkd operon, which catabolized isoleucine, valine and leucine, amino acids and produce precursors for the synthesis of branched fatty acids. At cold shock growing of bkdR deletion strain, isoleucine recovered cold sensitivity of bkdR deletion but valine did not restore cold sensitivity. Isoleucine is used as a precursor for the synthesis of anteiso-branched fatty acids. On the other hand, valine is used as a precursor for the synthesis of iso-branched fatty acids. This indicates that anteiso-branched fatty acid plays an important role at the cold shock condition.
Purpose : Development of renal scarring is associated with delayed diagnosis and treatment of urinary tract infection(UTI). This study was performed to clarify how soon treatment should be started to Inhibit renal scarring after onset of UTI and the factors associated with renal scarring in children with a first episode of febrile UTI. Methods : We retrospectively reviewed 163 patients with a first episode of febrile UTI under the age of 2 years from April 2000 to Ap,il 2004. All patients had a DMSA renal scan and voiding cystourethrogram done in the diagnostic period, 6 months after which a follow-up renal scan was done. After patients wet-e divided into 2 groups according to the duration of fever prior to start of treatment, the duration of fever after start of treatment, and total duration of fever, initial and follow-up DMSA scan findings were analyzed among the different groups. We compared the factors associated with renal scars between the groups with and without renal scars. Results : The initial DMSA renal scan identified abnormal finding in 23% of the patients who were treated $\leq$24 hr from the onset of disease and in 43% of those with fever more than 24 hr. Renal scars developed in 33% of patients who were treated $\leq$24 hr and 38% of those with fever >24 hr prior to treatment. Renal scars developed in 34% of patients with remission of fever $\leq$48 hr after treatment and ill 50% of those with fever >48 hr after treatment. The risk for renal scars was significantly higher in children who had total duration of feyer >72 hr(67%) than in those with shorter duration(19%). In children with renal scars, VUR was most highly associated with an increased risk of renal scar formation. Conclusion : Although children with a first episode of febrile UTI are treated within 24 hr after onset of the fever, renal damage cannot be prevented completely and it is mainly associated with VUR. (J Korean Soc Pediatr Nephrol 2005;9:56-63)
Purpose : Empirical antimicrobial treatment is indicated before bacteriological results are available for young children with febrile UTI to minimize renal scarring. To ensure appropriate therapy, knowledge of the prevalence of causative organisms and their susceptibility patterns to antimicrobials is mandatory. We performed a retrospective analysis investigating the local prevalence and resistance patterns of uropathogens, primarily E. coli, isolated from community-acquired UTIs. Methods : A total of 103 positive urine cultures from children with febrile UTI collected at Bundang CHA General Hospital from February 2004 to February 2005 were analyzed. Inclusion criteria were fever higher than $37.5^{\circ}C$, significant bacteriuria with single strain growth of at least 10s colony forming units/mL urine, and leukocyturia >5/HPF. Results : E. coli(89.3%) was the leading uropathogen followed by Enterococcus spp.(3.9%) Klebsiella spp.(2.9%), Citrobctcter spp.(1.9%) and Enterobacter spp.(1.9%). E. coli strains revealed a low proportion of antimicrobial susceptibility to ampicillin(AMP; 27.2%) ampicillinsulbactam(AMS; 34.8%) and trimethoprim-sulfamethoxazole(SXT; 65.2%). Susceptibility patterns to cephalosporins were as follows; cefazolin(1st generation; 91.3%), cefoxitin(2nd; 100%), ceftriaxone(3rd; 97.8%) and cefepime(4th; 97.8%). Three E. coli isolates produced ex tended - spectrum beta-lactamase(ESBL). Conclusion : Empirical treatment with AMP, AMS and SXT, which are commonly used in pediatric clinics, is not recommended for childhood UTI due to high incidence of resistance. The high level of susceptibility to cephalosporins makes these drugs reasonable alternatives. However the emergence of ESBL-producers, even though they are quite few, may have an impact on cephalosporin treatment in the future. (J Korean Soc Pediatr Nephrol 2006;10:18-26)
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