PURPOSE: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of TiO2 blasting implant surface. MATERIALS AND METHODS: Ten TiO2 blasting implant were used in this experiment. One implant was control group, and nine TiO2 blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. RESULTS: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the TiO2 blasting implant surface in SEM study while 180 mJ/pulse group altered the TiO2 blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. CONCLUSION: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.
Freezing ; Microscopy, Electron, Scanning

No abstract available.
Carcinoma, Mucoepidermoid*

BACKGROUND AND OBJECTIVES: Protein kinase C (PKC) is known to be related with development of various cells. In the heart, each isoform reacts differentially against agonists and the reaction changes during development. In this study, the roles of PKC isoforms (alpha, beta, gamma, delta, epsilon, zeta) were investigated through the localization of mRNA expression in the developing rat heart with in situ hybridization histochemistry. MATERIALS AND METHOD: The mRNA expression pattern of PKC isoforms (alpha, beta, gamma, delta, epsilon, zeta) was investigated with in situ hybridization histochemistry in developing and adult rat hearts. Whole body parasagittal sections were used for embryonal day 14 (E14), E16, E18 and heart sections were used for just born (P0), postnatal day 7 (P7), P14, P21 and adult rat. RESULTS: The expression of PKC alpha was found from E14, peaked at P7, and gradually decreased to adult level. The expression of PKC beta was observed from P14, peaked at P21, and decreased to adult level. The expression of PKC delta in the heart was observed from E14, peaked at P0, and abruptly disappeared at P14. The expression of PKC epsilon was observed from E14, peaked at P0, after that gradually decreased and disappeared at adult rat heart. The expression of PKC gamma and zeta was not found from any stage of developing rat heart. CONCLUSION: From these results, it is suspected that each PKC isoform may be differentially related with development of heart. The strong expression of PKC alpha, delta, epsilon around perinatal period, rapidly developing stage, suggests that PKC alpha, delta, epsilon may be related with rapid development of rat heart. And the late postnatal expression of PKC beta suggests that PKC beta may be related with maturation of rat heart.
Adult ; Animals ; Heart* ; Humans ; In Situ Hybridization ; Protein Isoforms ; Protein Kinase C* ; Protein Kinase C-epsilon ; Protein Kinases* ; Rats* ; RNA, Messenger*

A prospective study had been performed in infants with hydronephrosis due to ureteropelvic junction stenosis to determine adequate management plan. Forty infants (47 renal units) were selected for the study during the period from January 1995 to July 1997 in the Department of Pediatrics, Asan Medical Center. They were diagnosed prenatally or early postnatally (<3 months of age) on the basis of renal ultrasonography and techotium-99m-mercap- toacetyltriglycerine (MAG3) scan. The antero-poste- rior pelvic diameter (APPD) was measured from serial renal ultrasonography and relative renal function and clearance half time (T1/2) were calculated from serial MAG3 scan. Those who had accompanying other urogenital anomalies or vesicoureteral reflux were excluded in this study. Follow-up tests (ultrasonography and MAG3 scan) and surgical corrections, if necessary, were performed according to the predetermined algorithrn. The male to female ratio was 3: 1. Hydronephrosis was involved the left side in 24 renal units, the right side in 9 renal units, and the bilateral sides in 14 renal units. All the hydronephrotic renal units were divided into 2 groups; Group A (19 renal units) those had taken surgical correction, and group B (28 renal units) those revealed spontaneous improvement without surgical correction. The mean follow-up duration was 7.2+/-6.3 months in group A and 14.1+/-12.6 months in group B. The mean APPD in the first postnatal renal ultrasonography was 19.4+6.8 mm in group A and 10.0+/-3.0mm in group B and this was statistically significant (P<0.01). The rela- tive renal function of group A in the first MAG3 scan was under 35% in 7 renal units and over 35M in 12 renal units. In group B, the relative renal function was over 35% in the all 28 renal units. Tl/2 in the first MAG3 scan was longer than 20 minutes in the all 19 renal units in group A. In group B, Tl/2 was shorter than 10 minutes in 15 renal units, between 10 minutes and 20 minutes in 6 renal units, and longer than 20 rninutes in 7 renal units. The mean APPD of the 7 renal units in group B of which Tl/2 was longer than 20 minutes was 12.62.6mm and that of group A was 19.4+/-6.8mrn and this was statistically significant (P<0.01). In conclusion, the renal ultrasonography and MAG3 scan can be used effectively to determine the degree of the stenosis of the ureteropelvic junction in hydronephosis during infancy. When the babies are diagnosed with hydronephrosis due to ureteropelvic junction stenosis in the early infantile period, serial renal ultrasonography and MAG3 scan play an important role in the decision of the management.
Chungcheongnam-do ; Constriction, Pathologic ; Female ; Follow-Up Studies ; Humans ; Hydronephrosis* ; Infant ; Male ; Pediatrics ; Ultrasonography* ; Vesico-Ureteral Reflux

OBJECTIVES: REM sleep behavior disorder (RBD) has received little attention in epidemiologic studies. This study aimed to determine the prevalence of probable REM sleep behavior disorder (pRBD) in the elderly population and its clinical features. METHODS: A random sample of 1,588 was selected from a roster of 14,050 elderly population living in Osan city. The subjects were asked to fill out the REM sleep behavior disorder screening questionnaire (RBDSQ). Subjects whose score were 5 or higher on RBDSQ underwent a diagnostic phase of person-to-person assessment by experts in RBD. RESULTS: Among 1,588 subjects, 886 elderly subjects participated in the screening phase and 123 subjects were assessed in the diagnostic phase. Eleven subjects were diagnosed as having pRBD, so prevalence was 1.5% (95% CI=0.70-2.30%). The frequency of depression and cognitive decline was significantly increased in patients with pRBD compared to subjects without pRBD, and there was no difference in sleep disturbances between two groups. CONCLUSIONS: Probable REM sleep behavior disorder is not rare in the elderly but frequently under-recognized. More attention should be paid to evaluation and treatment of RBD.
Aged ; Depression ; Epidemiologic Studies ; Humans ; Mass Screening ; Prevalence ; Surveys and Questionnaires ; REM Sleep Behavior Disorder ; Sleep, REM

PURPOSE: The purpose of this study was to evaluate exophytically vertical bone formation in the mandibular premolar area of beagle dogs by the concept of guided bone regeneration with a titanium reinforced e-PTFE membrane combined with human demineralized freeze-dried bone. MATERIALS AND METHODS: Four one-year old beagle dogs were divided into control and experimental group. All mandibular premolars were extracted and surgical vertical defects of 5 mm in height were created in the extracted sockets. At 8 weeks after the extraction, TR e-PTFE membrane sized with 8 mm in length, 5 mm in width, and 4 mm in height was placed on the decorticated mandible, fixed with metal pins and covered with full-thickness flap and assigned as control group. In experimental group, decorticated mandibule was treated with TR e-PTFE membrane and human demineralized freeze-dried bone. The animals were sacrificed at 16 weeks after the regenerative surgery, and new bone formation was assessed by histomorphometric as well as statistical analysis. RESULTS: Average of new bone formation was 38% in the control group, whereas was 25% in the experimental group (p<0.05). Average of connective tissue formation was 42% in the experimental group, whereas was 30% in the control group (p<0.05). The lamellar bone formation with haversian canals was observed in the both groups. In the experimental group, the particles of human demineralized freeze-dried bone were observed after 16 weeks and complete resorption of graft was not observed. CONCLUSION: On the basis of these findings, we conclude that titanium reinforced e-PTFE membrane may be used alone for vertical guided bone regeneration, but demineralized freeze-dried bone has no additional effect on vertical guided bone regeneration.
Animals ; Bicuspid ; Bone Regeneration ; Connective Tissue ; Dogs ; Haversian System ; Humans ; Mandible ; Membranes ; Osteogenesis ; Titanium ; Transplantation, Heterologous ; Transplants

The present study was performed to evaluate the effect of tetracycline-HCl on the change of implant surface microstructure according to application time. Implant with pure titanium machined surface, GBA surface and RBM surface were utilized. Implant surface was rubbed with 50mg/ml tetracycline-HCl solution for 1/2min. 1min. 1 1/2min. 2min. and 2 1/2min. respectively in the test group. Then, specimens were processed for scanning electron microscopic observation. The results of this study were as follow. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two group. 2. In GBA surfaces, control group exhibit many porous depression, and each depression were divided by strict border. Experimental group applied with tetracycline-HCl for 2min. were similar with control group. But when applied for 2 1/2min. surface alteration and border breakdown started, resulting enlargement of the porous depression. 3. In RBM surface, control group exhibit rough, uneven surface with crater-like depression can be found. The surface alteration started when tetracycline-HCl was applied for 30sec. resulting breakdown of the crater-like depression. Depression became larger as applying time increased.
Depression ; Titanium

The purpose of this study was to evaluate the effects of toothpaste containing hydroxyapatite for patients who complained dental hypersensitivity. Before baseline of application of toothpaste with hydroxyapatite, tooth brushing instruction was done respectively and the several indices were measured at baseline, 2, 4, 8 weeks. Clinical indices were estimated, and responses to cold, compressive air, tactile stimulus were evaluated with verbal rating score. Relief effects and visual analogue scale were also evaluated. The results of this study were as follows 1. The occurrence rate of hypersensitivity in upper jaw was higher than that of lower jaws, and molar area showed more hypersensitivity than premolar and incisor area. Buccal site was hypersensitive followed by interproximal and lingual site. 2. Plaque index, gingival index and probing depth reduction were gradually improved after Tooth Brushing Instruction and using toothpaste. 3. Subjects showed most sensitive response to cold stimuli than compressive air and tactile stimuli. 4. The relief effect was increased during using tooth paste and complete relief was increased especially at 8 weeks. 5. Visual analogue scale was increased. In conclusion, it was confirmed that toothpaste containing microcrystalline hydroxyapatite have the relief effect of tooth hypersensitivity. During 8 weeks, stimulus responses were decreased and hypersensitivity relief effect was increased.

The purpose of this study was to evaluate the effects of toothpaste containing hydroxyapatite for patients who complained dental hypersensitivity. Before baseline of application of toothpaste with hydroxyapatite, tooth brushing instruction was done respectively and the several indices were measured at baseline, 2, 4, 8 weeks. Clinical indices were estimated, and responses to cold, compressive air, tactile stimulus were evaluated with verbal rating score. Relief effects and visual analogue scale were also evaluated. The results of this study were as follows 1. The occurrence rate of hypersensitivity in upper jaw was higher than that of lower jaws, and molar area showed more hypersensitivity than premolar and incisor area. Buccal site was hypersensitive followed by interproximal and lingual site. 2. Plaque index, gingival index and probing depth reduction were gradually improved after Tooth Brushing Instruction and using toothpaste. 3. Subjects showed most sensitive response to cold stimuli than compressive air and tactile stimuli. 4. The relief effect was increased during using tooth paste and complete relief was increased especially at 8 weeks. 5. Visual analogue scale was increased. In conclusion, it was confirmed that toothpaste containing microcrystalline hydroxyapatite have the relief effect of tooth hypersensitivity. During 8 weeks, stimulus responses were decreased and hypersensitivity relief effect was increased.

PURPOSE: Visual internal urethrotomy is a standard therapy for incomplete urethral stricture, and may also be a reasonable initial treatment for a short complete urethral stricture. The success rate and final results of the repeated internal urethrotomy were retrospectively assessed to figure out the appropriate indication for visual internal urethrotomy as an initial treatment for incomplete pendulous and bulbous urethral stricture; according to the stricture free month. MATERIALS AND METHODS: Between January 1990 and December 1999, an internal urethrotomy was primarily performed on 166 patients with urethral strictures. The exclusion criteria were complete urethral and posterior urethral stricture. Retrograde urethrography was performed under fluoroscopic control. When the stricture recurred, the urethrotomy was repeated as the primary procedure. RESULTS: With regard to the time to recurrence, the success rate of the group of stricture recurrence at 6 months was significantly lower than that of the stricture free group at 6 months. CONCLUSIONS: With regard to the stricture site and length, the stricture free month might be considered as an important predictor of the outcome of a repeated internal urethrotomy, and visual internal urethrotomy might be considered as an initial treatment method for incomplete urethral stricture under the following conditions; a bulbous stricture, a stricture length under 20mm, and stricture free at 6 months.
Constriction, Pathologic ; Endoscopy ; Humans ; Recurrence ; Reoperation ; Retrospective Studies ; Urethral Stricture*