The dissimilarities between South and North Korea have persisted in spite of the reconciliation campaign by both countries. The situation of the cleft lip & palate of North Korea was very unclear until now. The purpose of this study is to understand all the current facts of cleft lip & palate in North Korea so that we can find ways of helping North Korea in this field of medicine. The present data and analysis are extracted from North Korean textbooks. The results are as follow. 1. In North Korea, patients with CLP are treated by oral surgeons or maxillofacial surgeons. The detailed contents about the CLP are well described in the North Korean textbooks for the dental students. 2. The terminology of CLP in North Korea has changed from time to time, but the present terminology not being so different from South Korean counterpart. So there will be no particular problems in mutual communication. 3. The main classification for CLP in North Korea originated from Kernahan & Stark's classification as is with South Korea. 4. The incidence of CLP is 1 : 1,000-1,200 in North Korea, which is lower than that of South Korea. There is, however, some difference between the North and South Korean CLP in detailed statistics. 5. We found the North Korean physicians have shown much interest in pursuing the etiology and the prevention of CLP. 6. The timing of CLP operations varied a lot in North Korea. There was recommendation by few for the operation in much late age than in South Korea. 7. The classical operation techniques of cleft lip have changed. For unilateral cleft lip Tennison-Randall method was replaced by Millard I method: and for bilateral cleft lip LeMesurier method was replaced by Veau III and Tennison methods. But for cleft palate Pushback palatoplasty has been utilized consistently.

구순구개열은 악안면 영역의 선천기형 중 발생빈도가 가장 높으며 출생시부터 성장완료 시기까지 일관된 치료계획에 의한 종합적 진료체계가 필수적이다. 구순구개열의 개선을 위한 구개부 및 입숭? 조기 봉합 후의 반흔조직의 형성은 치열궁 협착 뿐 아니라 상악골 열성장에 의한 중안모의 함몰을 야기하며 이러한 상악골의 열성장 경향은 연령이 증가할수록 점진적으로 증가하는 성향을 보인다. 따라서, 성장잠재력을 이용한 조기의 악정형치료는 구순구개열 환자에서 반드시 필요하며, 적절한 치료 결과를 얻어내기 위하여 환자의 전후방 골격 형태 뿐 아니라, 성장 방향에 대한 고려가 필요하다. 그러나 혼합치열기의 악정형치료는 좋은 결과를 얻었다 하더라도 높은 재발 성향 및 잔여성장에 의한 악골관계의 변화가 예상되므로 장기간의 보정이 필수적이며 성장에 대한 지속적 평가가 이루어져야 할 것이다.

This study was performed to determine the prevalence of hypodontia and hyperdontia of permanent teeth among Korean schoolchildren, and to compare differences in the prevalence between Korea, other country, and other ethnic groups. The sample consisted of 346 girls aged 6.9～0.3 yr and 375 boys aged 6.8～0.4 yr on whom a panoramic radiograph was taken at Yeonchun-Gun community in Korea. The prevalence of congenitally missing teeth (third molars excluded) was 6.7% in boys and somewhat higher, 9.5% in girls, and 8.0% for both sexes combined. On the average, number of missing teeth per affected child was 1.9 teeth. The most commonly congenitally missing teeth were the mandibular second premolar (32.7%), followed by the mandibular incisor (28.7%), the maxillary second premolar (16.7%), and the maxillary lateral incisors (10.2%). The prevalence of supernumerary teeth was 2.1 % in boys, 1.4% in girls, and 1.8% for both sexes combined. The most common supernumerary teeth were the mesiodens (76.9%), followed by the supernumerary premolar (23.1 %). The affected male-female ratio was 1.6: 1.0. The prevalence of congenital missing teeth in this study was similar to in studies of Japanese, Danish, American and German. The frequency of hyperdontia was lower in this study than in studies of Chinese children, Japanese and American.

Midfacial retrusion is one of characteristics of cleft patients due to underdevelopment of the midface. In this case, Le Fort II advancement is indicated. But there has not been reported on intraoral approach to Le Fort II osteotomy for correction of midface, which traditional technique resulted in facial scar. To overcome the problems, Le Fort II osteotomy via only intraoral approach named 'Intraoral Le Fort IT osteotomy' was developed by Choung in 1994, this technique was applied to cleft patients. A new technique of Intraoral Le Fort IT osteotomy for correction of midface in cleft patients was successfully carried out with good results. This technique showed no noticeable relapse nor complications, which is reported.

Recents reports have demonstrated that force and direction is important during mandibular distraction osteogenesis. The purpose of this study was to evaluate the resistant force of internal pterygoid muscles and inquire into relationship between internal pte'Ygoid muscles and cephalometric parameters. Eighty four patients with class III malocclusion underwent bilateral sgittal splitting of ramus with intraoral vertico-sagittal ramal osteotomy. A spring scale were used for measuring for resistence of internal pterygoid mescles after splitting of ramus. Skeletal-dental cephalometric analysis was made following statistic package was used for correlation between resistence and cephalometric parameters. The resistant force of right internal pterygoid muscle was greater than left muscle in Korean with class III malocclusion and the force had a linear regression relationship with facial depth (distance between nasion and gonion). The results suggested that facial depth has significant correlation of the resistance of internal pterygoid muscle (p<0.05).

Midfacial hypoplasia in patients with clefts of the lip and palate is considered to be the result of congenital dysmorphogenesis. And cleft lip and palate developes facial deformity, jaw abnormality, speech problem, which is most frequent hereditary deformity in maxillofacial region. So cleft lip and palate is characterized by midface deformity which shaws maxillary anterior nasal septal deviation and deformity. Our study describes congenital correlates of midfacial hypoplasia by examining the displacement of a normal complement of parts, a triangular tissue deficiency low on the lip border on the columellar side, and a linear deficiency and displacement in the line of the bilateral cleft lip. 15 patients with bilateral cleft lip and palate were taken impression before operation, but the patient who had other abnormalities and complications were excluded. Average age is 3.4 months and they were classified into both complete, both incomplete and complete & incomplete group. The obtained results were as follows 1. There were no differences on intercanthal width and canthal width between each of the groups. 2. Both complete group had longer lateral ala length than both incomplete group, but there were no differences between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 3. Columella length was greater in both incomplete group than in both complete group, but there was no difference between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 4. Both complete group had longer ala width & ala base width than both incomplete group had. But there were no differences between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 5. There were no differences between each of the groups on upper lip length, but nose/mouth width ratio was greater in both complete group than in both incomplete group. 6. Pronasale(pm), subnasle(sn), la~rale superioris(ls), stomion(sto) points were located around the central vertical line of face but deviated to incomplete side in com. & incom. group. 7. Nasal tip protrusion was greater in both incomplete group and com. & incom. group than both complete group, but there was no difference between both incomplete group and com. & incom. group.

Alveolar cleft exists in 75% of cleft patients, In alveolar cleft patients, alar base is widening, palatal fistular formation, maxillary growth disturbance & tooth loss of adjacent area is raised, Alveolar bone grafting, especially iliac bone grafting, is a general treatment method. As operation timing, bone grafting is classified with primary, early secondary, secondary, & late secondary, Here we report cleft width, marginal bone height, bone resorption rate, grafted shape & bone densities after secondary iliac bone grafting was done in the Dept. of oral and maxillofacial surgery of chonbuk national university hospital. We compared cleft width to bone resorption rate and grafted shape. Also, alveolar bone densities of grafted and contralateral site was compared with Emago 3 package? (Oral Diagonostic System, The Netherlands), The data obtained were analyzed using Spearman's rho coefficients and sign test with SPSS for window, The results were obtained as follows. 1. As alveolar cleft width is increase, bone resorption rate is, too. This relation showed significant difference(P<.01). 2, In proximal & distal area, alvolar cleft width and bone graft contour after bone grafting had a reverse proportional difference. It was not significant difference(P>.05). 3. After 3 month, in bone density results by using Emago 3 package? with periapical standard view, occlusal view & panoramic view, differences between grafted bone and alveolar bone of contralateral site didn't show a significant difference(P>.05). Thus, differences of bone densities in the alveolar bones didn't exist.