Taehan Ch'ikkwa Uisa Hyophoe chi最新文献

This study is to evaluate the effect of the arthroscopic surgery for habitual dislocation of the temporomandibular joint. Conclusively, it is believed that arthroscopic surgery for habitual dislocation of the temporomandibular joint is easier method, has fewer complications, and lower recurrence rate, when compared with the conventional temporomandibular joint surgery.

The segmented arch technique has been developed with the three primary objectives; (1) force control over active and reactive teeth, (2) reduction in the number of chair hours required to treat a case, and (3) minimization of patient cooperation. The author experienced the efficiency and superiority of the segmented arch technique through the treatment of the Korean adult patient. With the possibility of accurately measuring the forces and moments delivered to tooth during orthodontic therapy, not only is it possible to improve the quality of orthodontic tooth movement, but it is also possible to learn about the nature of optimal forces that are needed clinically. A number of mechanisms have been described for initial levelling, deep overbite correction, anterior retraction, root movement and occlusal seating.

Mucoceles are commonly occurring lesions of the oral mucous membrane and the most common lesion involving minor salivary tissue. The incidence of mucoceles is understandable since accessary salivary gland tissue is widely distributed throughout the oral mucous membrane and trauma to the mucosa, which causes their formation, occurs frequently. But only a few studies have been reported that describe its detailed features. This is a retrospective study on the salivary mucoceles in the oral mucous membrane and based on clinical chart, biopsy request and photomicroscopic finding of 112 patients treated by Dept. of Oral Surgery in Seoul National University Hospital, during the period of last 10 years. The results were as following. 1. The age range of the 112 patients was 2 to 60 years, with a peak incidence in the second decade and a gradual decline thereafter. Of the 112 patients, 49 (44%) were males and 63 (56%) were females, the male-to-female ratio being 1:1.29. 2. The majority of these lesions were located on the lower lip but occurred with lesser frequently on the buccal mucosa, floor of the mouth, tongue, retromolar region, upper lip. 3. Of the 112 patients, 107 (95%) were treated by excision and only 5 were treated by marsupialization. 18 of 112 cases had recurrence and the recurrence rate in this study was 16%. 4. Only 3 of the 112 cases revealed an epithelial lining. This incidence indicates that the mucus-extravasation by the damage of excretory duct rather than the ductal dilatation by mucus-retention may play a critical role in the production of these lesions. 5. In 81 cases (72.3%) minor salivary gland were included in the excision biopsy, specimen. Changes observed in the glandular tissue were atrophy and infiltration of chronic inflammatory cell, but the secretory function of gland was thought to be normal in most cases because the changes were mild.

Mandibular condyle fractures develop frequently and show the variable type of injury and complication. New opinions have emerged from recent investigation into condylar fractures. The author investigated 246 patients with condylar fractures who visited SNUDH from January 1980 to August, 1988, 8. with regard to clinical and treatment aspects, area and displacement of fractures, associated teeth injury and other body injury, complications. At last I have got the following results. 1. The incidence to condylar fractures in a series of 765 mandibular fractures may be as high as 32.2%. 2. The male patients are 3 times more than female patients. The highest frequency was recorded in the group 21-30 years of age. (34.1%). 3. Falls caused the greatest number of condylar fractures (45.2%) and next was in assult (25.6%), traffic accidents (22.4%). 4. Unilateral condylar fractures were present in 74.8%, giving a left: right ratio of 1.2:1. In cases of unilateral fracture, subcondylar fractures were by far the commonest (32.9%) but in cases of bilateral fracture, condylar neck fractures were by far the commonest. In children under 15 years of age, condylar neck fractures were more common but in patients over 16 years of age, subcondylar fractures were common. 5. Anteromedial fracture dislocations were by far the commonest (20.3%). In children under 15 years of age, fracture deviations were common but in patients over 16 years of age, fracture displacements were common. 6. 44.7% of patients with condylar fractures sustained the teeth injuries. Teeth fractures were by far the commonest. 7. Single condylar fractures showed a frequency of 30.5%. Of the concomitant fractures elsewhere in the mandible, symphysis fractures were by far the commonest (54.1%). 8. Associated other body injuries showed a frequency of 28.0%. Of them, head injuries were by far the commonest. 9. The mean interval from injury to treatment was 14.3 days. Of the treatment of condylar fractures, open reduction was by far the commonest (70.3%). Closed reduction comprised 19.9% and functional therapy comprised 8.5%. 10. In 67 patients with possible follow up period, the following complications were developed, two ankylosis, anterior open bite, mouth opening limitation, mouth opening deviation.

The author observed 11 patients with buccal symptoms and history of surgical intervention for maxillary sinusitis who had come to KNUH during 3 years (1986. 6-1989. 5). As a result of careful analysis of clinical, radiological and histopathological findings, the author diagnosed them as postoperative maxillary cysts. The obtained results were as follows; 1. On the 11 patients, 6 were male and 5 were female and age distribution was from 35 to 53 years. Average age of patients was 45-year-old. 2. The most frequent chief complaint was buccal symptom type and 5 patients complained in the right side and 6 in the left. 3. The initial surgery was performed by means of the Caldwell-Luc's method for maxillary sinusitis in all cases and the duration between the initial radical operation and the onset of cyst was mainly from 10 to 35 years. The average was 24 years. 4. In radiological observations, bilateral lesions were noticed in the 3 patients. And 7 lesions were found in the right side and 7 in the left among the 14 lesions in 11 patients. Generally these lesions were shown monolocular cystic radiolucency with a well-defined, smooth margin and without marginal sclerosis. 5. Histopathologically, these cysts were basically composed of pseudostratified ciliated columnar epithelium and squamous metaplasia was occasionally founded.

The purpose of this study was to obtain the basic data of mandibular movements for prosthodontic treatment including craniomandibular dysfunction. The author measured the ranges of movements of mandible in the frontal, sagittal and horizontal trajectory using Saphon VisiTrainer Model 3 (Tokyo Shizaisha Inc.) in 8 male dental students of Seoul National University with normal occlusal relationship. The author obtained the following results; 1. The mean for maximal right and left laterotrusion in the frontal trajectory were 11.55mm and 10.51mm, and did not differ significantly (P greater than 0.05). 2. The mean for maximal protrusion from centric relation occlusion in the sagittal trajectory was 12.63mm and antero-posterior distance between CRO and CO was 1.51 mm. Maximum opening could not be trajected in 3 of 8 subjects. 3. The means of right, left laterotrusion and maximum protrusion were 10.97mm, 11.14mm and 10.31mm, and did not differ significantly (P greater than 0.05).

The authors experienced the bronchial aspiration of metal crown during dental treatment. This article discussed prevention and management of this event. The following conclusions were obtained from this study. 1. The preventive measures such as pharyngeal screen must be used in insertion and removal of metal casting. 2. The patient should be informed of this event before treatment. 3. If prosthesis was disappeared in oral cavity during dental treatment, a dentist must consult the radiologist for diagnostic x-ray taking, even though patient has no symptoms suggestive of aspiration of foreign body. 4. If expulsion of a prosthesis from the airway is not occurred, consultation to the ENT for bronchoscopy should be accompanied.

This is a retrospective statistical study on zygoma fractures. This study was based on 83 cases of zygoma fractures treated surgically in Dept. of Oral and Maxillofacial Surgery, Chungnam National University Hospital from May, 1985 to Sep., 1988. Among the many items the type of fractures and surgical methods were emphasized. For convenience sake, the zygoma fracture were classified according to Knight & North's classification. The results obtained are as follows: 1. The zygoma fractures occupied 31.9% of facial bone fractures. 2. The main age group were the second decade (37.5%) and the third decade (30.0%) and the ratio of mail and femail was 5.7:1. 3. The main contributing causes of fractures was traffic accident (71.3%). 4. The zygoma fractures were classified in 6 Group. Group 1. Undisplaced fractures were 8.4%. Group 2. Only arch fractures were 9.6% Group 3. Tripod with unrotated body were 32.5% Group 4. Tripod with medially rotated body were 20.5% Group 5. Tripod with laterally rotated body were 9.6% Group 6. Complex fractures were 19.2% 5. Fixation were required in 69 cases (83.1%) after adequate reduction. 6. Fixation area the most frequently used was zygomaticofrontal suture (71.1%), and infraorbital rim (43.3%), zygomatic arch (16.9%), zygomatic buttress (6%) were followed.

The purpose of this study was to operation the efficient pit and fissure sealing among the caries preventive methods. The authors examined the shape and depth of occlusal fissure in 48 extracted molar teeth and the following conclusions were obtained. 1. The percentages on the occlusal fissure type were 58.0% in I type, 21.0% in U type, 15.0% in K type, 6.0% in V type. 2. In each type, the average mean depth of the occlusal fissure were 1.15mm in I type, 0.53mm in U type. 1.11mm in K type, 0.56mm in V type.

The purpose of the present study was to determine the mercury contents in the hair of 44 dentists and 55 hygienists as dental personnel compared with 37 male and 35 female as controls, total 171 persons in Daegu City, to compare disposable capsule with reusable capsule in their ability to suppress mercury vapour leakage during trituration and opening the capsule, and to test 4 agents (water, detergents, developer, fixer) used to suppress mercury vaporization. The results were as follows: 1. The hair mercury contents of the dental personnel (6.69 +/- 4.01 ppm) were significantly higher than those of the controls (3.03 +/- 1.62 ppm) (p less than 0.01). 2. The hair mercury contents of the hygienists (7.01 +/- 4.48 ppm) were slightly higher than those of the dentists (6.22 +/- 3.40 ppm) but not significant difference (p greater than 0.05). But hair mercury contents in the dentists and hygienists of the same period of year of exposure were 5.22 +/- 1.87 ppm, 7.01 +/- 4.48 ppm, respectively, so hair mercury contents of the hygienists were significantly higher than those of the dentists (p less than 0.05). 3. In the controls, hair mercury contents of the male (3.48 +/- 1.56 ppm) were significantly higher than those of the female (2.56 +/- 1.60 ppm) (p less than 0.05). 4. There was no correlationship between the hair mercury contents of hygienists and the period of year of exposure (r = 0.0062, p greater than 0.1) but significant correlationship in dentists (r = 0.5410, p less than 0.002). 5. Disposable capsule exhibited mercury vapour leakage during trituration and opening the capsule, 0.80 microgram, 1.97 microgram, respectively so opening the capsule was increased by 2.5 times. Reusable capsule exhibited mercury vapour leakage during trituration and opening the capsule, 0.94 microgram, 7.26 micrograms, respectively so opening the capsule was increased by 7.8 times. 6. Compared with reusable capsule, disposable capsule suppressed mercury vapour leakage during trituration and opening the capsule 1.2 times, 3.7 times, respectively. 7. Of various agents used to suppress mercury vaporization, 0.56 microgram of mercury in fixer, 0.81 microgram of mercury in developer, 0.94 microgram of mercury in detergent, 1.38 microgram of mercury in mater were released and mercury vaporization was suppressed in fixer compared with air by 12.7 times, with water by 2.5 times.