• Restorative Dentistry and Endodontics
• /
• 제21권1호
• /
• pp.353-359
• /
• 1996

The purpose of this study was to investigate the concentrations of Leukotriene B4 in relation to the clinical symptom of pulpitis in human dental pulp. Pulps obtained from 3 groups of teeth: normal uniflamed teeth(N=22), asymptomatic teeth with deep caries or large restorations(N = 21) and symptomatic teeth with the clinical diagnosis of irreversible pulpitis(N = 15). Pulps were dissected from normal un inflamed teeth and extirpated from asymptomatic and symptomatic teeth during routine endodontic treatment and stored in liquid nitrogen ($-70^{\circ}C$). The levels of Leukotriene B4 in individual or pooled pulps were measured by radioimmunoassay and the mean levels of each group were compared statistically(Kruskall-Wallis oneway ANOVA test). The results were as followings : 1. In normal pulp, low levels of Leukotriene B4 were measured. 2. In pulps from asymptomatic and symptomatic teeth had significantly higher levels of Leukotriene B4 than normal pulps(p<0.01). 3. The levels of Leukotriene B4 in pulps from symptomatic teeth were significantly higher than those of pulps from asymptomatic teeth(p<0.01). These results suggest that Leukotriene B4 play a cretain role in inflammatory process of dental pulp and have a relationship with clinical symptoms of pulpitis.

• 대한치과기공학회지
• /
• 제20권1호
• /
• pp.51-60
• /
• 1998

The artificial resin teeth used for removable prosthesis have good physical properties, but they have great wear rate. The purpose of this study is to compare the wear characteristics of several artificial resin teeth, such as Myerson teeth(Myerson Crop), Trubite IPN(Dentsply), Endura Posterio(Shofu), SROrthosit(Ivoclar), Trubite Biotone(Dentsply), Five samples of each resin tooth were abraded against natural teeth, type III gold for 150,000 cycles on the wear machine. The results obtained were as follow 1. The wear rate of artificial resin teeth when opposing enamel was the lowest in Myerson teeth($8.60{\mu}m$), followed by Trubite IPN($41.30{\mu}m$), Endure poster($63.00{\mu}m$), SR-Orthosit($68.40{\mu}m$), Trubite Biotone($209.90{\mu}m$) 2. The wear rate of artificial teeth when opposting type III gold specimens was the lowest in Myerson teeth($13.50{\mu}m$) followed by Endura Posterio($14.75{\mu}m$), Trubite IPN($53.40{\mu}m$), SROrthosit($54.20{\mu}m$), Trubite Boitone($341.50{\mu}m$)

• 대한치과보철학회지
• /
• 제8권1호
• /
• pp.9-14
• /
• 1968

A total of 11,039 permanent missing teeth and their 2,696 prosthetic replaced teeth in 6,123 Korean patients were selected for this study, Analyzing the data according to age, sex, jaw and the location, following results were obtained. 1. Tooth mortality and replacement were higher in female than in male. 2. Replaced teeth were only 24 percent of missing teeth. 3. More teeth were extracted and replaced on lower jaw in young patients and on upper jaw in old patients. 4. There are no significant difference in right and left sides of both jaws in missing and replaced teeth, respectively. 5. First molar was the highest percentage in both mortality and replacement. 6. Upper tooth mortality and replacement were higher in anterior portion and lower in posterior portion.

• Imaging Science in Dentistry
• /
• 제42권1호
• /
• pp.41-45
• /
• 2012

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.

• 치과방사선
• /
• 제21권2호
• /
• pp.275-285
• /
• 1991

The clinical and radiographic features of 655 congenitally missing teeth were studied with full mouth periapical radiograms and/or pantomograms from 368 persons visited the Department of Oral Radiology, Infirmary of Dentistry, Kyung Hee University during January 1981 to December 1989. The obtained results were as follows: 1. The prevalence of congenitally missing teeth was revealed to be 8.75% in total examined persons, and there was a higher prevalence in females (9.5%) than in males (8.0%). 2. The most frequently missing teeth were mandibular second premolars (24.6%), followed by mandibular lateral incisors (21.7%), maxillary second premolars (16.2%), and maxillary lateral incisors (11.5%). 3. There was a higher prevalence in the mandible (60.3%) than in the maxilla (39.7%), and no significant differences between right (49.65%) and left (50.35%) side. 4. In number of congenitally missing teeth per person, 54.6% had one missing tooth, and 32.9% had two missing teeth. 5. In persons with one or two congenitally missing teeth, the most frequently missing tooth was mandibular lateral incisor, and the second premolar was the tooth most frequently missing in those persons with more than three congenitally missing teeth.

• 대한소아치과학회지
• /
• 제8권1호
• /
• pp.65-75
• /
• 1981

The author have studied on the pulp responses to the electric pulp stimulator (Pyo-Cure)(R) in the primary molar age from 4 to 11 of the 186 children (male 100, female 86). The total numbers of teeth used in this study were 1096. The results were as follows ; 1. The difference in responses between the teeth of the male and female was not statistically significant. 2. The difference in responses between the teeth of the right and left sides was not statistically significant. 3. The difference in responses between the teeth of the upper and lower jaws was not statistically significant. 4. The responses of the teeth in the older age is higher than its of the early age. 5. Inspite of advanced root resorption of the primary molars, except severe root resorption, the responses of the teeth was higher according to increasing the age. 6. The responses of the teeth were decreased severely in the primary molars as it becomes exfoliation time.

• 한국치위생학회지
• /
• 제10권3호
• /
• pp.441-448
• /
• 2010

Objectives : This study was conducted in order to investigate the percentage of adolescents who brush their teeth after lunch and its related factors using raw data from the Fourth Korea National Health and Nutrition Examination Survey. Methods : In order to extract adolescents to be subjected to this study, 300 adolescents between the age of 12 to 18 who are currently attending junior and senior high school were chosen out of a total of 4,594 subjects. The results from the health surveys and the oral checkup results from the medical examination conducted on these adolescents were analyzed. Results : 1. The percentage of adolescents who brush their teeth after lunch was 33.9%. 2. The percentage of the adolescents who brush their teeth after lunch differed significantly according to the gender (p<0.001), age (p<0.05), the time of their recent visit to the dentist (p<0.05), and whether they had suffered from permanent tooth caries (p<0.05). 3. The factors which affect whether the adolescents brush their teeth after lunch was their gender, the total number of the times they brush their teeth per day, and their age. Conclusions : Effective oral health education methods should be reinforced in order to increase the percentage of the adolescents who brush their teeth after lunch.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제26권1호
• /
• pp.73-79
• /
• 2000

A material of 48 patients with 60 avulsed and replanted permanent teeth were followed retrospectively in the period of 1996. 1 to 1998. 12 (mean observation period=1year 7months). The age of the patients at the time of replantation ranged from 9 to 63 years (mean=24 years). Clinical records of patients were reviewed to obtain valid data concerning the extent of injury and treatment provided. Pulpal and periodontal healing states were examined with periapical x-rays and clinical examination procedures (i.e. percussion test and mobility test) at their recall visit. Root ankylosis was found in fifty-two teeth(87%) and root resorption in twenty-four(40%). Only two of the replanted teeth(3%) showed partial regeneration of the periodontal ligament. Six teeth(10%) resulted in tooth loss, but the remaining fifty-four were clinically well functioning. Most of teeth have mild marginal bone loss accompanied by gingival retraction without pathological periodontal pockets. The incidence of root resorption was much higher in younger age group. However, it was not affected by the interval between avulsion and replantation, the condition of supporting tissues, the degree of root formation and the type of splinting, indicating that multiple factors involved in determining the prognosis of replanted teeth. Based on these findings, avulsed teeth in unfavorable conditions (i.e. long extra-alveolar periods, etc.) should be preserved if possible.

• 대한치과보철학회지
• /
• 제31권4호
• /
• pp.542-548
• /
• 1993

This study was designed to investigate the effect of missing teeth, prosthesis and malalignment on the smile. The full smile photographs of 145 Korean adults(male 114 : female 31) were taken and classified by the lip pattern, the relationship between the lip and the teeth, and the number of teeth displayed in a smile. Besides, the esthetic smile score were estimated by five dentists. Obtained data were compared and analyzed. The results obtained were as follows : 1. The esthetic level of missing teeth group and malaligned group was lower than that of the normal group. 2. The esthetic level of prosthesis group had no difference with that of the normal group. 3. The Number of teeth displayed in a smile had the most effect on the esthetic level in each experimental group.

• 대한치과의사협회지
• /
• 제11권2호
• /
• pp.131-133
• /
• 1973

A Case of a supernumerary teeth on the buccal side of upper right and left molar teeth was observed from a 21 years young Korean female. The characteristics were as follows : 1. The site of the occurrence were resemble on the right and left sides. 2. The cusps of the supernumerary tooth on the right side were resemble to the premolar, and the cusp of the left one was added by one more cusp than the normal molar tooth. 3. The supernumerary teeth were smaller than the normal teeth size. 4. The right and left teeth had only one root.