The purpose of this study is to find the optimal reconditioning method for a debonded bracket base. In this study, metal brackets and ceramic brackets are used. There are devided into five groups by reconditioning methods (A : control(new bracket), B : heat treated, C : grinded with green stone, D : sandblasting for four seconds, E : sandblasting for eight seconds). Each reconditioned brackets were bonded and shear bond strength was measured by universal testing machine. After debonding, enamel surfaces were examined under stereoscopic microscope to determine the adhesive remnant index. The Microstructure of reconditioned bracket were examined by SEM (JSM 5200, Japan) and stereoscopic microscope (SZ-ST, Japan). 1. In metal bracket groups, sandblasting for eight seconds revealed the greatest shear bonding strength and its strength was above that of control group. 2. In ceramic bracket groups, sandblasting for eight seconds revealed the greatest shear bonding strength but its strength was below that of control group. 3. As sandblasting time was increased, shear bonding strengh of metal bracket was increased very much, but in ceramic brackets, shear bonding strength exhibited limited increase. This difference was caused by macro-mechanical retentive areas of ceramic brackets were broken for their brittle characteristics of material.
Adhesives ; Ceramics ; Dental Enamel ; Hot Temperature ; Orthodontic Brackets*

Cancer may be a disease of genes, arising from genetic damage of diverse sorts-recessive and dominant mutations, large rearrangement of DNA and gene translocation on chromosomes, all leading to distorisions of either the expression or biochemical function of genes. The search for these genetic damage in neoplastic cells now is the most important in cancer research. It has been found that the cancer relevant genes were located on the specific regions of chromosomes. To determine whether epidermal growth factor receptor(EGFR), P53 and bcr genes located in chromosomes 7, 17 and 22 are altered, we examined 12 neuroepithelial tumor with Southern blot analysis(five low grade astrocytoma, two high grade astrocytoma, two medulloblastoma, on oligodendroglioma, one ependymoma, one choroid plexus papilloma). The loss of heterozygosity(LOH) of EGFR gene was detected in two cases of medulloblastoma. The rearrangement of EGFR gene was detected in a case of ependymoma. The LOH of P53 gene was found in a case of choroid plexus papilloma and low grade astrocytoma. The rearrangement of P53 gene was founs id a case of oligodendroglioma. The LOH of bcr gene was observed in two cases of medulloblastoma and low grade astrocytoma. The rearrangement of bcr gene was observed in two cases of high grade astrocytoma. These results suggested that tumorigenesis and tumor development in the neuroepithelial tumor may invlove specific gene changes in chromosomes 7, 17 and 22.
Astrocytoma ; Blotting, Southern ; Carcinogenesis ; Choroid Plexus ; DNA ; Ependymoma ; Epidermal Growth Factor ; Genes, erbB-1 ; Genes, p53 ; Loss of Heterozygosity ; Medulloblastoma ; Neoplasms, Neuroepithelial* ; Oligodendroglioma ; Papilloma, Choroid Plexus

No abstract available.
Aneurysm ; Arteriovenous Malformations* ; Brain* ; Intracranial Aneurysm*

Severe head injury results in the suppression of cellular immunity associated with dysfunctioning of effector lymphocytes, such as helper T cells(CD4) (and cytotoxic T cells(CD8). Despite progress in the management of increased intracranial pressure following head injury, infection remains the most common complication and the primary cause of prolonged hospitalization and death. This study attempts to assess the cellular immune function following head injury according to the degree of severity, and to establish the clinically available parameters of cell mediated immune(CMI) function, which can then be used for coherent prediction of infection risk. Eighteem head injury patients without severe systemic injury, who divided into three subgroups depending on the severity of head injury, were estimated with the use of CMI multitest kit(Merieux Institute, France) to test delayed-type hypersensitivity(DTH) and enumerated the circulating lymphocyte subpopulation(pan T-cell marker CD3, helper T cell marker CD4, cytotoxic T cell marker CD8 and B-cell marker CD19) on the 1st, 7th, and 21th day of injury. Patients were monitored for evidence of infection for this period. Fourteen patients had no reaction to any antigens of the DTH skin test(anergy) and the remaining four patients had also some degree of anergy. Seven patients became infected and all of them were anergic. There were significant decrease of circulating effector T lymphocytes, both CD4-positive and CD8-positive cells, within 24 hours of injury in the mild as well as the moderate and severe head injury group. CD4-positive cells were nearly completely recovered by the 7th day of injury. CD8-positive cells had sustained significant decrease even after 3 weeks of injury. There was no significant change in pan T-cells(CD3-positive cells) and B-cells(CD19-positive cells). The results suggest that DTH skin test and effector T cell enumeration are both relatively simple and highly sensitive parameters for monitoring CMI function. Especially, anergy of DTH skin test can be used for indicator to predict risk of infection. Mild as well as moderate and severe head injuries may result in the suppression of cellular immunity associated with the dysfunctioning of effector T cell.
B-Lymphocytes ; Craniocerebral Trauma* ; Head* ; Hospitalization ; Humans ; Immunity, Cellular* ; Intracranial Pressure ; Lymphocytes ; Skin ; Skin Tests ; T-Lymphocytes

In order to determine the predisposing factors to cerebral aneurysm rupture and to examine the relationship between circadian periodicity of blood pressure change and the rupture of an aneurysm, the authors investigated activities of the patients of events as well as diurnal and seasonal variations in the onset of subarachnoid hemorrhage (SAH) in 766 consecutive patients. The authors also compared the difference of these data between patients with a history of hypertension and patients without a history of hypertension. The results showed that the onset of SAH was associated with defecation and/or urination in 12.3%, working on the jab in 11.8%, housework including washing clothes in 10.3%, sleeping in 7.4% and bathing and/or washing up in 7.2%. The incidence of the onset of SAH associated with defecation an/or urination was higher in patients with a history of hypertension than in patients without a history of hypertension(p<0.05). The diurnal variation of the onset of SAH showed two broad peak times from 6 to 10 a.m.(21.8%) and from 5 to 8 p.m.(18.3%). The seasonal variation of the onset of SAH showed the incidence to be slightly higher in winter than in any other seasons autumn and winter, the leading activities of the patients or events in the onset of SAH was defecation and/or urination and, in summer, it was job performing. We concluded that the onset of the SAH is related not only to the physiological circadian periodicity of blood pressure change but also to the activities or events which induced a sharp rising blood pressure and changing the venous and cerebrospinal fluid pressure.
Aneurysm ; Baths ; Blood Pressure ; Causality* ; Cerebrospinal Fluid Pressure ; Defecation ; Housekeeping ; Humans ; Hypertension ; Incidence ; Intracranial Aneurysm* ; Periodicity ; Rupture* ; Seasons* ; Subarachnoid Hemorrhage ; Urination

In order to evaluate the effect of the lumbar epidural steroid injection in the low back pain and/or radicular pain. We studied 66 patients who were treated and followed for an average of 8.6 months. In the initial evaluation, main pain sites were as follows: low back pain in 41 patients, buttock pain in 7 patients, and leg pain. In 18 patients. Immediate response and delayed response in the patients were studied. Immediate response within 1 day after injection revealed the following : dramatic improvement in 3.0%;some improvement in 56.1%; no improvement in 27.3%; and more aggravated in 13.6%. Delayed response after 1 month revealed the following : 15.2% continuously maintained improvement; 9.1 showed progressive improvement;36.4% experienced recurring pain; 27.3% had no improvement; and 10.6% had aggravating pain. The effect of the lumbar epidural steroid injection was not affected by the severity of pain in the initial evaluation. Better improvements were noted in patients who suffered radicular pain than those who suffered low back or buttock pain. Good prognostic factors were young age and male. Complications that the patients suffered were transient injection pain(6), edema of the face or extremity(10), transient leg weakness(5) and dural puncture(1). The number of patients who wanted to recommend this procedure to others were 22(33.3%). In conclusion, epidural steroid injection was one of the methods in the management of the patients who suffered low back pain and/or radicular pain and had no effect by any other therapies.
Buttocks ; Edema ; Humans ; Leg ; Low Back Pain* ; Male

There were 84 cases of brainstem auditory evoked potential(BAEP) and 90 cases of somatosensory evoked potential(SSEP) from the 124 cases of head injury. The studies were performed within the first three days after head injury in most cases and after ten days in emergency operative cases. The results of BAEP and SSEP studies recorded from 67 normal volunteers were used as a control group. The latency, amplitude and wave pattern of the evoked potential were examined and a peak or interpeak latency were considered abnormal when it exceeded the corresponding mean(2SD found in the control group. The wave patterns were arranged in BAEP as grade I:all waves were normal; grade II: waves I, II, III were abnormal;grade III:waves IV, V, VI were abnormal;grade IV:all waves were abnormal. In SSEP as grade I:all waves were normal;grade II:N13 wave was abnormal;grade III:N19wave was abnormal;grade IV:all waves were abnormal. The abnormal findings by percentage were:47.6% in latency of BAEP, 68.9% in latency of SSEP, 49.4% in wave pattern of BAEP and 87.8% in wave pattern of SSEP. The BAEP was superior to SSEP in correlation to clinical parameters including GCS, duration of coma, basal cisterns in initial brain CT scan and Glasgow outcome scale(GOS). As a BAEP criterion, the wave V latency and the BCT(III-V interpeak latency) and as a SSEP criterion, the central conduction time(N19-N13) were more correlated to duration of coma and GOS. The appearance of the basal cisterns on initial brain CT is significantly correlated with wave V and BCT of BAEP only. Grade I and II were reliable predictors of a good prognosis. Therefore, we concluded that BAEP and SSEP are adjunctively diagnostic tests for determining the outcome of head injuried patients.
Brain ; Brain Stem* ; Coma ; Craniocerebral Trauma* ; Diagnostic Tests, Routine ; Emergencies ; Evoked Potentials ; Head* ; Healthy Volunteers ; Humans ; Prognosis ; Tomography, X-Ray Computed

We reviewed 6 epidermoid and 3 dermoid tumors of the brain treated surgically for a period of 4 years. The favorite sites for epidermoids were the cerebellopontine angle, whereas dermoids were found in the cerebellar vermis. The average age was 44.2 years for the patients with epidermoid tumors and 24.6 years for the patients with dermoid tumors. Average duration of symptoms was much shorter in dermoids than in epidermoids. Computed tomography scans revealed hypodense lesions with irregular borders without contrast enhancement. Magnetic resonance imaging was performed on 3 patients;the tumors showed decreased signal intensity relative to the brain on T1-weighted images and increased signal intensity relative to the brain on T2-weighted studies. Five were removed totally and 4 subtotally. Aseptic meningitis and transient facial nerve palsy were causes of postoperative morbidity.
Brain ; Cerebellopontine Angle ; Dermoid Cyst* ; Facial Nerve ; Humans ; Magnetic Resonance Imaging ; Meningitis, Aseptic ; Paralysis

Five cases of chronic encapsulated intracerebral hematomas(so called "chocolate cysts") presented slowly progressive neurological deficits and hence mimicked brain tumors. The median duration of symptoms was 21 days. The first symptoms were severe headache and vomiting. At one case generalized seizure was noted. Computed tomography almost consistently demonstrated ring shaped lesions with central high density and minimal perifocal edema. Cerebral angiographic studies showed avascular mass lesions. All cases had superficial white matter lesions. Soft, well-encapsulated, organized, large intracerebral hematomas were removed surgically. Arteriovenous malformations were detected in two cases. All cases recovered completely but at one case postoperative brain swelling was noted transiently. Increasing awareness of "chocolate cyst" as a clinical and pathological entiry was necessary.
Arteriovenous Malformations ; Brain Edema ; Brain Neoplasms ; Cacao* ; Edema ; Headache ; Hematoma* ; Seizures ; Vomiting

No abstract available.
Carpal Tunnel Syndrome*