A particular problem associated with osseointegrated implants is the fact that the implants lack a periodontal ligament. Thereby, marginal inflammation around an implant may cause more serious bone loss than does marginal inflammation around teeth with a periodontal ligament. In addition, osseointegrated implants are ankylosed and do not haute the same mobility as natural teeth with a periodontal ligament. Implants with a periodontal ligament would eliminate these problems. In order to explore the possibility of producing a periodontal ligament around titanium dental implants, a study of the attachment of cultured periodontal ligament cells to titanium was carried out. Periodontal ligament cells obtained from premolar teeth of individuals undergoing tooth extraction for orthodontic reasons were cultured on titanium-coated epon blocks. Sections of the blocks were cut perpendicular to the surface of the cell layer. Transmission electron microscopy of the periodntal ligament cells/titanium interface showed that there was no evidence of attachment at the cultured periodontal ligament cells titanium interface. The microfilaments, commonly located adjacent to the titanium surface, run mostly parallel to the titanium surface. The study showed that cultured periodontal ligament cells did not create an attachment structure on a titanium surface similar to that of natural teeth.
Actin Cytoskeleton ; Bicuspid ; Dental Implants ; Inflammation ; Ligaments ; Microscopy, Electron, Transmission ; Periodontal Ligament* ; Titanium* ; Tooth ; Tooth Extraction

BACKGROUND AND OBJECTIVES: One of problems for the management of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) is the difficulty of determining the affected ear using Ewald's second law. The purpose of this study is to develop the new "Bow and Lean Test (BLT)" to determine easily the affected ear of HSC-BPPV and evaluate its efficiency. MATERIALS AND METHOD: We compared the efficiency between the classical method and BLT in 26 patients with HSC-BPPV. The classical method is based on Ewald??s second law comparing the intensity of nystagmus or symptoms in head roll test. BLT is based on the direction of both "bowing nystagmus" and "leaning nystagmus" at head's bowing and leaning state on sitting position. The affected ear is the same direction of bowing nystagmus in canalolithiasis and the same direction of leaning nystagmus in cupulolithiasis. RESULTS: In 26 patents (15 canalolithiasis, 11 cupulolithiasis), 3 (11.5%) patients did not show a prominent affected ear in the classical method, and 7 (26.9%) patients showed the different affected ear between two methods. All 10 patients were successfully treated with just one trial of barbecue rotation based on the affected ear in BLT. Three patients did not show any bowing or leaning nystagmus. The side with canal paresis in all 4 patients, who showed significant canal paresis in bithermal caloric tests, was equal to the affected ear based on BLT. CONCLUSION: "Bow and Lean Test" (also called "Choung's test") is a new method which can easily determine the affected ear of HC-BPPV.
Caloric Tests ; Ear ; Head ; Humans ; Jurisprudence ; Paresis ; Semicircular Canals ; Vertigo*

BACKGROUND AND OBJECTIVES: One of problems for the management of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) is the difficulty of determining the affected ear using Ewald's second law. The purpose of this study is to develop the new "Bow and Lean Test (BLT)" to determine easily the affected ear of HSC-BPPV and evaluate its efficiency. MATERIALS AND METHOD: We compared the efficiency between the classical method and BLT in 26 patients with HSC-BPPV. The classical method is based on Ewald??s second law comparing the intensity of nystagmus or symptoms in head roll test. BLT is based on the direction of both "bowing nystagmus" and "leaning nystagmus" at head's bowing and leaning state on sitting position. The affected ear is the same direction of bowing nystagmus in canalolithiasis and the same direction of leaning nystagmus in cupulolithiasis. RESULTS: In 26 patents (15 canalolithiasis, 11 cupulolithiasis), 3 (11.5%) patients did not show a prominent affected ear in the classical method, and 7 (26.9%) patients showed the different affected ear between two methods. All 10 patients were successfully treated with just one trial of barbecue rotation based on the affected ear in BLT. Three patients did not show any bowing or leaning nystagmus. The side with canal paresis in all 4 patients, who showed significant canal paresis in bithermal caloric tests, was equal to the affected ear based on BLT. CONCLUSION: "Bow and Lean Test" (also called "Choung's test") is a new method which can easily determine the affected ear of HC-BPPV.
Caloric Tests ; Ear ; Head ; Humans ; Jurisprudence ; Paresis ; Semicircular Canals ; Vertigo*

A procedure descried by Fontan and Baudet in 1971 successfully bypassed the right ventricle in Tricuspid Atresia patients, after then many modification of the Fontan operation had been described and applied to many cyanotic complex heart patients. Forty patients with a variety of cardiac malformation underwent the Fontan operation at Seoul National University hospital (September 1978 to June 1986). The age at operation ranged 2 months to 18 years. Each number of cases according to basic cardiac anomaly was as follows; 17 in Tricuspid Atresia, 17 in Univertricular Heart, 2 in Double outlet of Right Ventricle, 2 in Transposition of the Great Arteries and 2 in Criss-cross heart. Total mortality rate after the Fontan operation was 50%. There was only one late death (>30 days). Mortality rate under 4 years of age (67%) was higher than that between 4 and 18 years of age (40%). we observed a significantly higher mortality for patients who, in the immediate postoperative period, had central venous pressure greater than 25cm H2O. 45% among survivals did not require further medication. Although mortality rate after the Fontan operation is much higher than that in the foreign literature, operative mortality will decline with the increased expirence of surgeon and the effective patients selection.
Arteries ; Central Venous Pressure ; Crisscross Heart ; Fontan Procedure* ; Heart ; Heart Ventricles ; Humans ; Mortality ; Postoperative Period ; Seoul ; Tricuspid Atresia

BACKGROUND AND OBJECTIVES: The use of intraoperative facial nerve monitoring (IOFNM) improves facial nerve outcomes in acoustic neuroma surgeries, but the role of IOFNM in middle ear and mastoid surgeries is poorly defined. This study was performed to evaluate the role of IOFNM in middle ear and mastoid surgeries and to systemize IOFNM. SUBJECTS AND METHOD :We carried out a prospective study of 83 patients who undertook middle ear and mastoid surgeries with IOFNM. We checked the facial nerve dehiscence and estimated its location and length using a surgical microscope ('surgical dehiscence'). We stimulated the facial nerve with constant current, unipolar stimulation using Nerve Integrity Monitor (NIM)-2(TM) (Xomed (TM), U.S.A.) and estimated the minimal threshold of electric current making the electromusculography of facial muscle changes. RESULTS: Thirty six (43.4%) of 83 cases showed 'surgical dehiscence' and all responded to 0.7 mA or less of electrical stimulation. The most common site of 'surgical dehiscence' was middle portion of the tympanic segment. We defined the response to electrical stimulation within 0.7 mA as 'electrical dehiscence.' 'Electrical dehiscence' was presented in 63 (75.9%) cases and 82.5% of these cases responded to stimulation of 0.4 mA or less. The mean threshold of minimal electrical stimulation was 0.28 mA for tympanic segment and 0.48 mA for mastoid segment. CONCLUSION: "Electrical dehiscence" based on responses of electrical stimulation is safer than "surgical dehiscence," which is based on microscopic observation in middle ear and mastoid surgery. Based on this study, we recommend the electrical stimulation of 0.7 mA for first screening and 0.4 mA for second exploration in defining facial nerve using intraoperative NIM-2(TM) monitoring in middle ear and mastoid surgeries.
Ear, Middle* ; Electric Stimulation ; Facial Muscles ; Facial Nerve* ; Humans ; Mass Screening ; Mastoid* ; Monitoring, Intraoperative ; Neuroma, Acoustic ; Prospective Studies

No abstract available.

BACKGROUND AND OBJECTIVES: Otitis media with effusion (OME) is one of the most common diseases in children and may be frequently related with dizziness. However, the association between OME and dizziness seems to be not clear and remains controversy. The purpose of this study was to determine the incidence of dizziness in children with long lasting OME, and to investigate the difference in vestibular functions between children with long lasting OME and the control group. MATERIALS AND METHOD: Thirty one children who had long-lasting OME over than 6 months (study group) and 28 normal hearing children without OME who were scheduled for adenotonsillectomy (control group), were given questionnaires and vestibular function tests (VFT) including electronystagmography (ENG) and rotation chair test (RCT). Statistical analysis was performed with chi-square test. RESULTS: Dizziness was found in 7 (22.6%) of 31 children in the study group and 2 (7.1%) of 28 children in the control group (p>0.05). The difference of abnormal findings in VFT between the study group and the control was not significant except visual vestibulo-ocular reflex (VVOR) in RCT. Most of the correlations in the study group, bilateral vs. unilateral OME, OME with dizziness vs. OME without dizziness, and preoperative vs. postoperative, were not significant. CONCLUSION: We did not find any evidences of significant difference of the incidence of dizziness and findings of VFT between children with long lasting OME and children without OME. However, there was a significant abnormal response in VVOR in RCT in children with long-lasting OME, suggesting the children with OME may be more dependent on the nonvestibular system including visual compensation to maintain balance.
Child* ; Compensation and Redress ; Dizziness ; Electronystagmography ; Hearing ; Humans ; Incidence ; Otitis Media with Effusion* ; Otitis Media* ; Otitis* ; Surveys and Questionnaires ; Reflex, Vestibulo-Ocular ; Vestibular Function Tests

BACKGORUND: infusion of propofol by a target-controlled infusion (TCi) system is effective in achieving conscious sedation for anxious patients presenting for dental surgery. However, there is no report of conscious sedation for mandibular fracture patients using propofol TCi. The objective of this study was to evaluate the appropriation of a conscious sedation using propofol for mandibular fracture patients. METHODS: Twenty patients with a mandibular fracture undergoing an open reduction and miniplate insertion operation were analyzed. We anesthetized patients using a propofol infusion by a TCi system (Diprifusor :Master TCi:Pilot Anesthesia is, France) with local anesthesia using lidocaine. The BiS score was evaluated continually during surgery using a microcomputer (A-2000 BiS monitor , Aspect Medical System, USA). We set the infusion machine at a target concentration 2mug/ml, and adjusted the propofol concentration for a BiS score range of 80-85. infusion rate, total dosage, duration of induction, recall of operative procedure and cooperation scores were checked. BiS, heart rate, noninvasive arterial blood pressure, and SpO2 were recorded during the operation. RESULTS: The mean BiS score was 82.95, the mean target concentration of propofol was 2.645mug/ml, the mean infusion rate was 136.3mug/kg/min, and the mean cooperation score was 2.5, the patients were cooperative. The score of amnesia was 0.2, almost patients did not recall the intraoperative event. The mean duration of stay in the recovery room was 22.2 minutes, and the most frequent side effect was pain on injecion of propofol. CONCLUSiONS: Conscious sedation with propofol TCi is an effective anesthesia method substitute for general anesthesia with quick emergence, few side effects, and safety for mandibular fracture patients.
Amnesia ; Anesthesia ; Anesthesia, General ; Anesthesia, Local ; Arterial Pressure ; Conscious Sedation* ; Heart Rate ; Humans ; Lidocaine ; Mandibular Fractures* ; Microcomputers ; Propofol* ; Recovery Room ; Surgical Procedures, Operative

No abstract available.

The purpose of this study was to evaluate the effects of DFPR on differentiation of mouse calvarial cell in vitro, to examine the possibility for periodontal regeneration. 10microgram/ml of DFPR was used as experimental concentration. osteogenic medium only was assigned as control, Experimental 1 was supplemented with 10nM dexamethasone, Experimental 2 with 10microgram/ml DFPR and Experimental 3 with 10nM dexamethasone + 10microgram/ml DFPR. cellular activity was evaluated by MTT method at 8, 12, 16 days, expression of mRNA of ALP, osteopontin, osteocalcin, collagen type-1 was detected by RT-PCR method at 4, 8, 12, 16 days of culture . extent of mineralization was observed by Von Kossa staining at 16 day of culture. The results are as follows 1)Any acceleration of differentiation was not observed at expression of differentiation marker, 2) Decrease in expression of extracelluar matrix and in bone nodule formation was observed The results suggested that DFPR have negative effect on the rate of differentiation on rat calvarial cell, decrease extracelluar matrix formation ,decrease bone nodule formation. Ongoing studies are necessary in order to determine effect of DFPR on periodontal regeneration.
Acceleration ; Animals ; Collagen ; Dexamethasone ; Methylene Chloride* ; Mice* ; Osteocalcin ; Osteopontin ; Rats ; Regeneration ; RNA, Messenger