• The korean journal of orthodontics
• /
• v.27 no.3 s.62
• /
• pp.473-479
• /
• 1997

This author tried to find if the size of the frontal sinus can be used as a diagnostic aid to predict the manldibular growth pattern in growing Patients in lateral cephalogram utilizing the fact the the frontal sinus completes its growth in earlier stage but the mandible continues to grow until later. At this study, the 228 samples were divided into 3 groups as skeletal Class I, II, III malocclusions and three indicies(ANB, APDI, Wits) were measured which indicate the mandibular body length and the antero-posterior relationship of maxilla and mandible to evaluate their relations with frontal sinus. And results were obtained as followings 1. The size of frontal sinus is highly related to ANB, APDI, Wits and mandilar body length.(p<0.001) 2. the size of the frontal sinus of the Cl III malocclusion group was on the lateral cephalogram larger than Cl I and Cl II group.

• The korean journal of orthodontics
• /
• v.25 no.5 s.52
• /
• pp.567-575
• /
• 1995

The purpose of this study was to investigate the effect of the partial glossectomy on the mandibular growth of growing rats. Thirty one Sprague-Dawley rats four weeks old were divided into two groupes : the first group served as the control and the second group was partially excised in the tongue of the rats. The experimental animals were sacrificed at 4 and 8 weeks after partial glossectomy. The changes of the rat mandibular growth following partial glossectomy were observed biometrically from dry bone specimens. The findings were as follows : 1. Partial glossectomy of growing rat produced inhibitory effects on the growth of the mandible and did not change the original shape of the mandible. 2. Among the factors affecting mandibular growth, the presence of the proper tongue size was essential. 3. Partial glossectomy of the growing rats could not change general growth of the rats whole bodies.

• The korean journal of orthodontics
• /
• v.27 no.3 s.62
• /
• pp.481-492
• /
• 1997

In order to investigate the possibility of using a cervical vertebral maturation indicator as a mandibular growth indicator, the relationship of cervical vertebral maturation and mandibular & body height growth changes was assessed in biennial serial lateral cephalometric radiographs of eighteen korean male and fourteen korean female while they were 8.5 to 18.5 years old. The following results were obtained. 1. It was a reliable method to evaluate skeletal maturation by using cervical vertebrae. 2. In general, cervical vertebral maturation stages of females were higher than those of males at the same age and there were significant differences in statistics at the age of 10.5, 14.5. 3. The age of a female at the same cervical vertebral maturation stage were earlier than that of a male. 4. In the case of males, significant Ar-Gn increases were found between stage 3 and 4,5; Ar-Go increases between stage 4 and 5. 5. In the case of females, significant S-Gn and Ar-Gn increases were (end between stage 3 and 4. 6. Significant body height increases were found between stage 3 and 4 in both sexes. 7. The peak velocity of body height and mandibular length was observed between cervical vertebral maturation stage 3 and 4 in both sexes. 8. The relationship between mandibular & body height changes and specific maturation stage of cervical vertebra was found, therfore using a cervical vertebral maturation indicator as mandibular growth indicator is quite within realms of possibility.

• The korean journal of orthodontics
• /
• v.20 no.3 s.32
• /
• pp.463-498
• /
• 1990

전기적 자극에 의한 골성장기전의 개념을 이용하여 임상적 효율성을 증진시키기 위한 연구는 현재 교정학을 비롯한 치과영역에서 활발히 진행되고 있는 분야 중의 하나이다. 전기적 자극의 여러 형태 중의 하나인 전자기장과 하악의 기능적 전방 이동을 유도하는 악기능교정장치가 백서의 하악과두 성장에 미치는 영향을 구명하기 위하여 본 연구를 시행하였다. 생후 4주된 Sprague Dawley계 백서 48마리를 대조군 12마리, 실험군 36마리로 나누고, 실험군은 다시 전자기장을 가한 군, 하악골 전방이동 장치를 장착시킨 군, 전자기장과 하악골 전방이동 장치를 병용시킨 군으로 분류하여 각각 12마리씩 실험동물을 배정하였다. 각 군의 실험동물은 15 HZ의 특수 전자기장이나 하악전방이동 자치가 하루10시간씩 작용되도록 특별히 제작한 실험장치 속에 넣어 1주간, 4주간씩 사육하여 희생시킨 후 하악골을 분리하고 연조직을 박리한 후 $10\%$ formalin에 보관하였다. 하악골 길이를 측정하기 위해 0.05mm까지 계측 가능한 캘리퍼를 이용하여 하악과두의 후연에서 이공까지의 거리를 계측하였고, 하악과두를 절제하여 0.5M EDTA에 탈회시켜 파라핀 포매를 하였다. 표본의 절단방향은 시상평면에 평행하게 하여 $6{\mu}m$두께로 연속절단 하였으며, 그 중 중심의 3절편을 취하여 통법에 의한 H-E 중염색을 시행하였다. 하악골 계측과 H-E 중염색 표본을 통한 조직학적 관찰을 통해 다음과 같은 결론을 얻었다. 1. 4주군에서 전자기장만에 노출된 실험군은 대조군에 비해 하악골 길이가 유익성 있게 증가되었다. 2. 전자기장과 하악골 전방이동 장치를 병용한 실험군은 하악골 전방이동장치만을 사용한 실험군에 비하여 하악골 길이가 증가되었다. 3. 전자기장에 노출된 실험군은 전구 연골아세포(prechondroblast)의 증식, 비대연골 세포층의 세포간질 및 연골내 골화층의 석회화가 모두 증가되었다. 4. 본 실험에 사용한 15 HZ전자기장의 주요작용부위는 백서의 하악과두 성장지역 중 연골내 골화의 석회화 지역이며, 또한 이는 하악골 전방이동 장치와 병용시 하악과두 성장을 촉진시킬 수 있음이 관찰되었다.

• The korean journal of orthodontics
• /
• v.29 no.3 s.74
• /
• pp.303-315
• /
• 1999

The aim of this study was to evaluate the morphology of the mandibular symphysis and anterior alveolar and skeletal relationship under the influence of the rotational growth pattern of mandible in skeletal Class III malocclusion. A total of U untreated adult subjects were divided into two groups-forward rotational growth pattern group, backward rotational growth pattern group-according to the suggestion of Skieller et al.. The antero-posterior position, vertical relationship, mandibular symphysis and anterior alveolar and skeletal relationship were assessed on lateral cephalometric radiographs. Mandibular symphysis and anterior alveolar and skeletal relationship in each subject were studied and the following conclusions were drawn : 1. Concerning the antero-posterior position, forward rotational growth pattern group showed significantly larger SNA, SNB. Conceming the vertical relationship, all measurements showed statistically significant differences. 2. Forward rotatioal growth pattern group showed significantly larger IMPA, MnAD, backward rotational growth pattern group showed significantly larger MxABH. 3. There was no statistically significant difference in symphysis ratio to mandibular plane between forward and backward rotational growth pattern group. 4. In the correlative analysis of rotational growth pattern of mandible and mandibular symphysis, anterior alveolar and skeletal relationship, statistically significant correlations in overbite, IMPA, MnAD, symphysis width were showed.

• The korean journal of orthodontics
• /
• v.27 no.1
• /
• pp.105-117
• /
• 1997

This investigation examined the effect of lateral shift of mandible from functional occlusal interference on the growth of mandible and the growth pattern of mandible shown after the removal of occlusal interference. The followings were performed with the results below : the changes in mandible and condylar cartilage were studied in the experimental group with upper right, lower left incisors cut for 2 and 4 weeks- an 4-week-old rats and the experimental group which had cut for 4 weeks and suspended for 2 weeks. 1. In the 2-week experimental group, the left mandibular length, condylar length, mandibular height and condylar area seemed smaller than those on the right and the normal group ; the right mandibular length and condylar area were smaller than the normal group. 2. In the 4-week experimental group, left condylar area was smaller than the right, but due to the quick changes in adaptability of left mandible, right and left mandibular lengths were similar. compared with the normal group, however, mandibular length and condylar area still remained small. 3. In the 6-week experimental group, the left and the right appeared similar with the mandibular length remaining still shorter than the normal group. 4. In the sagittal plane, the proliferation of the cartilage layers of the left condylar cartilage of the 2-week group appeared to have general repression compared with the right and the normal group. The right side also showed repressed growth compared with the normal group. In the 4 and 6-week groups, however, it was similar to the normal group. 5. In condylar cartilage volume, no significant difference was noted in the comparisions of left and right of the experimental group, nor in the comparison of the same sides of experimental wand normal groups. Based on the above, in case of contralateral incisal cutting in rats, it was observed that the growth of mandible and condyle of the cutting side was repressed, at the same time, the quick adaptability led to similar changes of growth in left and right mandibles. But judging from the similar phenomena throughout the whole experimental period in the changes of condylar cartilage volume in the experimental, right and left, and normal groups, the general overall growth of condylar cartilage was found unrepressed. It was also recognized that the growth of condylar cartilage can take in various directions.

• The korean journal of orthodontics
• /
• v.31 no.1 s.84
• /
• pp.39-50
• /
• 2001

In proceeding with orthodontic treatment, the prediction for the shape, growth rate and growth direction of mandible plays a major role to set up the treatment plan and determine its period and prognosis. Various approaches being made so far have shown that the linear and angular measurement using lateral cephalograms are relatively accurate to estimate them. This study was purposed to find the shape of mandible more clearly by preventing the overlap of the Condyle head area which appears in lateral cephalogram, and to estimate its growth rate by comparing the growth quantity and ratio via lateral area measurement. This experimental was performed against 40 patients total, of which Class I of 14, Class II of 9 and Class III of 17 consist. Wide open lateral cephalograms of 40 patients were taken over average period of 4 Year 3 Months, then the linear and angular measurements were carried out with 11 itemized lists. Autocad Rl4 application program was utilized to draw their appearance, measure and compare their lateral area. As a result of study, conclusions were made as follows; 1. Mandibular body length (gonion-menton) tended to increase in order of CIII, CI and CII, and Mandibular body length of CIII group had a tendency to grow twice faster than that of CII group. 2. In lateral items such as Go-Me, A-Cd, B-Cp, E-F and G-H, CIII showed a significant increase on the year-average quantity and rate of the growth, and especially apparent difference was observed in CIII group rather than CII group. 3. For the 4 Year 3 Months period, the year-average growth quantity of lateral area of the mandible was $1.0cm^2$ for Class I, $0.8cm^2$ for Class II and $1.4cm^2$ for Class III, which corresponds to $11.9\%,\;11.8\%\;and\;20.3\%$ of growth ratio respectively. Thus, growth ratio almost 2 times more than other groups was observed in group CIII while growth ratio between group CI and CII has little difference. 4. Considering the results as above, it can be proposed that the difference in size of the mandible between groups is caused by the difference in the growth rate and growth quantity of the mandible, which generated in the middle of growth, rather than the difference in size of congenital Jaw-bone.

• The korean journal of orthodontics
• /
• v.28 no.2 s.67
• /
• pp.189-201
• /
• 1998

The purpose of this study was to evaluate the characteristics of craniofacial skeleton on orthognathic surgical cases with skeletal Class III malocclusion. For this study, 74 students at the dental college of Chosun University volunteered as a normal occlusion group. They had well-balanced faces and good occlusions with acceptable Class I molar relationship. They had not received orthodontic treatment and had no signs or symptoms of temporomandibular joint dysfunction. 45 malocclusion patients enrolled for orthognathic surgical treatment with skeletal Class III malocclusion at the Department of Orthodontics, College of Dentistry, Chosun University. On the basis of this study. the results of this study were as follows: 1. Skeletal Class III malocclusion was largely due to the overgrowth of mandible in man and the undergrowth of maxilla in woman. 2. The mandible was antero-inferiorly overgrown by large MP-HP angle and large genial angle in orthognathic surgical cases with skeletal Class III malocclusion. And also, upper incisors were severely labioversioned, but on the other hand lower incisors were linguoversioned. 3. In female, lower-third facial height was characteristically shortened in comparison with middle-third facial height and also, lower facial throat angle was small in male.

• The Journal of the Korean dental association
• /
• v.47 no.10
• /
• pp.628-636
• /
• 2009

낭은 상피세포로 싸여있는 병적인 공간으로 내부가 액체나 반액체로 채워져 있다. 악골에서 낭은 다른 골 부위에서보다 더 흔하게 발생하는데 이는 대부분의 낭이 치아 형성 후에 악골에 남아있는 치성잔류물로부터 발생하는 경우가 많기 때문이다. 구강악안면부에서 발생하는 낭은 연조직에서 발생할 수도 있지만 대부분 골내에서 발생하고, 법랑질 상피나 치배와 관련해 악골내에 발생하는 치낭성이다. 치낭성은 WHO분류에서 발생근원에 따라 크게 염증성과 발육성 기원의 두 가지 군으로 분류되고, 발육성 낭은 치성과 비치성으로 세분할 수 있다. 악골에 발생하는 낭은 대부분이 치낭성이며 가장 흔한 악골 낭종은 치근단낭으로 염증성이고, 발육성인 함치성낭과 치성각화낭도 다음으로 발생률이 높은 편이다. 소아환자에서 함치성낭과 치성각화낭의 발병률이 성인보다 더 높았다. 비치성낭 중에서 비구개관낭이 가장 많이 발생하며, 연조직에서 발생하는 낭과 상피세포 경계가 없는 낭성 병소인 가성낭(pseudocyst)은 드물게 관찰된다. WHO에서 치성각화낭과 서회화치성낭은 파괴적 성장을 하고 재발 경향이 높으므로 양성 낭성 종양으로 재분류하고 있다.

• The korean journal of orthodontics
• /
• v.33 no.4 s.99
• /
• pp.247-257
• /
• 2003

Various methods have been used on patients with skeletal Class II division 1 malocclusion. The activator, Frankel appliance, headgear, Herbst appliance, and Twin-block appliance are some examples. The ideal treatment effect using these appliances would be to inhibit horizontal and vertical growth of the maxilla while promoting mandibular growth and obtaining optimum dentition. The Teuscher appliance has a simultaneous combined headgear effect with maxillary growth inhibition and an activator effect with mandibular growth promotion. The purpose of this study was to examine how well these effects were clinically obtained and the results are as follows. 1. The forward growth of the maxilla was effectively inhibited. 2. The downward-forward growth of the maxillary dentoalveolar complex was inhibited. 3. Growth promotion of the mandible was not observed. 4. The overjet, overbite, molar key were effectively improved. 5. The protruded upper lip and facial profile were unproved.