The purpose of this study was to investigate the functional adaptation of the tongue, the hyoid bone, the digastric muscle and the upper airway and the variables predicting postoperative stability following orthognathic surgery in patients with mandibular prognathism. 18 patients were selected(8 men and 10 women) for this study, who had received orthognathic surgery. Their lateral cephalograms, those were taken preoperatively, immediate postoperatively and over 6 months follow-up, were traced and analysed. The results were as follows: 1. The downward displacement of the hyoid bone and extended head posture were recognized, right after operation. Statistically significant correlations were found between the changes of the mandibular position and the digastric muscle and the change of head posture during operation. 2. The tongue was displaced downward following the hyoid displacement postoperatively. Statistically significant correlations were found between the change of the mandibular position and the change of the distance of the tongue and hard palate, and between the change of head posture and the changes of the upper airway sizes, the digastric muscle and the hyoid position during over 6 month's follow-up. 3. The change of the distance of the tongue and hard palate was the most significant factor for prognosis during over 6 month's follow-up. 4. There were no variables before operation to predict the postoperative stability and the constriction of the upper airway.
Constriction ; Follow-Up Studies ; Head ; Humans ; Hyoid Bone* ; Male ; Orthognathic Surgery* ; Palate, Hard ; Posture ; Prognathism* ; Prognosis ; Tongue*

Nitinol wires are now widely used in the orthodontic field because of their unique shape memory effect and superelasticity. But sometimes Nitinol wires are deformed in clinical use. Fatigue load is possible cause of Nitinol deformation. To determine the effect of fatigue load to the mechanical properties of Nitinol, various fatigue cycle(1X10(4), 2X10(4), 3X10(4), 4X10(4), 5X10(4), 1X10(5)) were applied to 0.017 X 0.025 inch Nitinol. The results obtained were as follows; 1. Applied load increased as fatigue cycle increased in three point bending test. 2. Maximum tensile strength and elongation decreased as fatigue cycle increased. 3. In SEM, brittle fracture pattern was increased when fatigue cycle increased.
Fatigue* ; Memory ; Tensile Strength

The 35 patients of femur neck fracture treated with bipolar hemiarthroplasty were followed up for an average of 18 months with the range of 12 months to 5 years after bipolar hemiarthroplasty from Jan. 1986 to Dec. 1992. 1. Mean age of the patient was 68 years old(25-93) and mean hospitalization period was 55 days. 2. Associated medical problems were diabetes mellitus in 6 cases, cerebrovascular disease in 5 cases, rectal cancer in 1 case and pulmonary tuberculosis in 1 case. 3. An anterior dislocation, one of the early complication occured in 1 case, and superficial infection in 3 cases(8.5%), a deep infection, one of the late complication occured in 1 case. 4. The clinical result was focus on the functional hip assessment of bipolar hemiarthroplasty after femur neck fracture, and the functional results evaluated by Lunceford's Method were excellent in 22 cases(63%), good in 5 cases(14.3%), fair in 5 cases(14.3%), poor in 3 cases(8.6%). 5. The bipolar hemiarthroplasty was satisfactory method for the displaced femur neck fracture in the elderly patients, but to return the patient's preinjury activity level, more active postoperative rehabilitation should be required.
Aged ; Cerebrovascular Disorders ; Diabetes Mellitus ; Dislocations ; Femoral Neck Fractures ; Femur Neck ; Femur ; Hemiarthroplasty ; Hip ; Hospitalization ; Humans ; Methods ; Rectal Neoplasms ; Rehabilitation ; Tuberculosis, Pulmonary

For the purpose of investigating mesiodistal axial inclination of posterior teeth in normal occlusion group, open bite and deep bite group and investigating the correlationship between the axial inclination of posterior teeth and overbite of anterior teeth, a cephalometric study was performed on the subjects consisted of normal occlusion group(40), open bite group(71 : Angle's Class I 21, Class II, division 1 25, Class III 25) and deep bite group(64 : Angle's Class I 23, Class II, division 1 21, Class III 20). Mesiodistal axial inclination of posterior teeth to occlusal, mandibular and palatal plane were measured. The findings of this study were as follows: 1. Upper and lower posterior teeth were more mesially inclined to occlusal plane in open bite group than in deep bite group. 2. Lower posterior teeth were more mesially inclined in deep bite group than in open bite group in Angle's Class II, division 1 malocclusion but there were no significant differences in Angle's Class I and Class III malocclusion. 3. There was no significant correlationship between the axial inclination of posterior teeth to each plane and overbite of anterior teeth in open bite group. 4. There was a significant correlationship between the axial inclination of upper and lower second premolar to occlusal plane and overbite of anterior teeth in Angle's Class I, Class II, division 1 and Class III malocclusion.
Bicuspid ; Dental Occlusion ; Malocclusion ; Open Bite* ; Overbite* ; Tooth*

The effect of topical application on the number of S. mutans was tested in a group of 44 orthodontic patients (mean age, 12Y 3M). They were divided into 5 groups according to the method using NaF and SnF2. The number of S. mutans CFU were counted in stimulated saliva of each subject at baseline, and after one, two, three, and eight weeks. The following results were obtained. 1. In NaF rinsing group, and NaF topical application and NaF rinsing group, the number of S. mutans per ml saliva was not significantly changed. 2. In SnF2 topical application group, and SnF2 topical and NaF rinsing group, the number of S. mutans per ml saliva was significantly reduced. 3. After 8 weeks, there were no significant reduction of the number of S. mutans in comparison with baseline.
Fluorides* ; Humans ; Saliva ; Streptococcus mutans* ; Streptococcus*

OBJECTIVES: The aim of this study was to identify the health and environmental risk factors of air contaminants that influence environmental and respiratory diseases in Gyeongju, Pohang and Ulsan in South Korea, with a focus on volatile organic compounds (VOCs). METHODS: Samples were collected by instantaneous negative pressure by opening the injection valve in the canister at a fixed height of 1 to 1.5 m. The sample that was condensed in -150degrees C was heated to 180degrees C in sample pre-concentration trap using a 6-port switching valve and it was injected to a gas chromatography column. The injection quantity of samples was precisely controlled using an electronic flow controller equipped in the gas chromatography-mass spectrometer. RESULTS: The quantity of the VOC emissions in the industrial area was 1.5 to 2 times higher than that in the non-industrial area. With regards to the aromatic hydrocarbons, toluene was detected at the highest level of 22.01 ppb in Ulsan, and chloroform was the halogenated hydrocarbons with the highest level of 10.19 ppb in Pohang. The emission of toluene was shown to be very important, as it accounted for more than 30% of the total aromatic hydrocarbon concentration. CONCLUSIONS: It was considered that benzene in terms of the cancer-causing grade standard, toluene in terms of the emission quantity, and chloroform and styrene in terms of their grades and emission quantities should be selected for priority measurement substances.
Benzene ; Chloroform ; Chromatography, Gas ; Electronics ; Electrons ; Hot Temperature ; Hydrocarbons, Aromatic ; Hydrocarbons, Halogenated ; Republic of Korea ; Risk Factors ; Styrene ; Toluene ; Volatile Organic Compounds

PURPOSE: To evaluate the stability, activity level and clinical results of an autologous hamstring and Bone-patellar tendon-bone (BPTB) graft in an Anterior cruciate ligament (ACL) reconstruction. MATERIALS AND METHODS: Between September 1997 and January 2003, 22 patients with an ACL reconstruction with an autologous four strand hamstring tendon, and 30 patients with a BPTB autograft were enrolled in this study. At the time of the final follow-up, the patients were evaluated by stress radiographs using a Telos instrument, the Lysholm score, Tegner activity score, IKDC activity grades, and anterior kneeling pain. RESULTS: An evaluation of the anterior laxity using the Telos instrument revealed no significant difference in the hamstring and BPTB groups: side to side difference 2.6 mm in the hamstring group vs 2.3 mm in the BPTB groups (p>0.05). The Lysholm score improved from a preoperative score of 58 to a postoperative score of 88 in the hamstring groups and from 56 to 91 in the BPTB groups. The Tegner score for the hamstring groups was 2.4 preoperatively and 5.8 at the final follow up, and the Tegner score for the BPTB groups were 2.3 and 6.2 preoperatively and after the last follow-up, respectively. The Tegner score was similar in the two treatment groups (p>0.05). According to the IKDC rating system, 9% were normal and 64% were almost normal in the hamstring group. In the BPTB group, 10% were normal and 67% were almost normal. Anterior kneeling pain after a reconstruction with the hamstring tendon autograft (13%) was significantly less common than with the patellar tendon autograft (37%)(p<0.05). CONCLUSION: The hamstring autograft for an ACL reconstruction decreased the incidence of anterior kneeling pain and produced equivalent clinical results to the BPTB autograft.
Anterior Cruciate Ligament Reconstruction* ; Anterior Cruciate Ligament* ; Autografts ; Bone-Patellar Tendon-Bone Grafts* ; Follow-Up Studies* ; Humans ; Incidence ; Patellar Ligament ; Tendons ; Transplants

Purpose: This study was conducted in order to examine the usefulness of osteoconductive bone substitutes with zeta potential control (geneX® ds; Biocomposites, England) by comparing the complications and radiographic evaluation with or without geneX® ds augmentation for internal fixation with proximal femur nail antirotation (PFNA) for treatment of osteoporotic unstable intertrochanteric fractures. Materials and Methods: A retrospective study of 101 patients who underwent fixation with PFNA in osteoporotic unstable intertrochanteric fractures was conducted from December 2015 to August 2020. The radiographic evaluation and complication rates were compared between patients with geneX® ds (Group A: 41 cases) and those without geneX® ds (Group B: 60 cases). Results: In radiological valuation, the degree of blade sliding from the time immediately after surgery to one year after surgery was 1.4±1.2 mm and 5.8±2.7 mm in Group A and Group B, respectively (P<0.001). During the same time frame, a significant difference of 2.3±2.2° and 7.4±3.1° , respectively (P<0.001), in varus collapse, was observed for Group A and Group B. Conclusion Among patients fixed with PFNA for treatment of unstable intertrochanteric fractures, less blade sliding and varus collapse was observed for those with geneX® ds augmentation compared to those without it. In addition, there was no increase in the incidence of complications. The authors believe it can be regarded as a safe and effective additive for intramedullary fixation for treatment of unstable intertrochanteric fractures.

Neck fracture is a major cause of death in traffic accidents and this injury pattern occurred normally in a frontal collision or overturn process. This study investigates a case of neck fracture from a low speed collision. In this case examined, the passenger in the front seat of the car was pulled back and did not have the seat belt on. As the vehicle slipped on a frozen road surface in a downward hill and crashed into the shoulder of the road at low speed. But strangely, even though his neck is fracture there were not any collision marks on interior of the car. This study applied computer simulation to analyze this case and we found out that the upper part of the person was rotated and raised at the time of collision and his neck was fully bent by interference with roof and we also know that the seat belt did not resist the passenger who pulled back his seat.
Accidents, Traffic ; Cause of Death ; Computer Simulation ; Humans ; Neck Injuries ; Neck* ; Seat Belts ; Shoulder

In order to examine the immunoresponse of host cells to Enterococcus faecalis, this in vitro study monitored the production of Interleukin-2 (IL-2), Interleukin-4 (IL-4) and Transforming growth factor-beta1 (TGF-beta1) in human lymphocytes. Lymphocytes were activated with PHA in the presence or abscence of sonicated extracts of E. Faecalis (SEF) and further incubated for 72 hours. The level of each cytokine was measured by ELISA. Data were analyzed with Kruskal-Wallis test and Mann-Whitney U test (P < 0.05). PHA-activated group did exhibit higher level of IL-2 and IL-4 than untreated control group. The levels of expression of both cytokines were significantly decreased following the treatment of high (25 microg/ml) and medium concentration (12.5 microg/ml) of SEF (P <0 .05) than those of PHA activated group. But low concentration (5 microg/ml) of SEF showed the similar level of IL-2 and IL-4 production as those of PHA activated group. TGF-beta1 was unaffected by SEF treatment. These results suggested that E. faecalis may suppress IL-2 and IL-4 production by lymphocytes and this could be one of possible factors why E. faecalis are found frequently in the teeth with failed endodontic treatment.
Cytokines ; Enterococcus faecalis* ; Enterococcus* ; Enzyme-Linked Immunosorbent Assay ; Humans* ; Interleukin-2* ; Interleukin-4* ; Lymphocytes* ; Tooth ; Transforming Growth Factor beta1*