• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.799-817
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• 1994

The purpose of this study was to evaluate the initial skeletal pattern and growth change of whom had responsed well to chincap therapy. 93 patients seleted for this study were in mixed dentition and treated with chincap for more than 2 years. And 54 subjects were selected from these total samples and classified into two groups by the improvement of four measurements : ANB difference, APDI, Wits appraisal, and AF-BF. One was good response group which consisted of 26 children and the other was poor response group with 19 patients. Various measures of the craniofacial structure in the initial lateral cephalograms and the annual increments were calculated and analyzed by comparing two groups with t-test. The results were as follows : 1. Good response group had more horizontal growth pattern in initial stage of treatment than poor response group, and the contributing factors of this result were anterior posterior facial height ratio, gonial angle, lower genial angle and SN-mandibular plane angle. 2. The maxilla was positioned more anteriorly in good response group. 3. The amounts of vertical growth of maxilla was smaller but the horizontal growth of maxilla was larger in good response group. 4. The mandible rotated more infero-posteriorly in good response group. 5. The good response group had more vertical growth pattern of mandibular condyle.

• The korean journal of orthodontics
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• v.21 no.3
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• pp.685-699
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• 1991

The purpose of this report is to review vertical dysplasia such as openbite or deep bite in skeletal Class III malocclusion and their treatment modality and to present two cases treated with MEAW. The results obtained were as follows A. Open bite case 1. The treatment time was 3 year 8 months. 2. Upper and lower incisors showed extrusion and especially lower anterior alveolar process showed remodelling. 3. The mesially inclined upper and lower molars were uprighted and especially lower first molars showed extrusion that means remodelling of alveolar bone. 4. Normal overbite and overjet were established. 5. Mandible showed slight clockwise rotation. 6. Maxilla showed slight downward bending of ANS part. 7. Upper lip showed downward drop and lower lip showed retraction and touch between upper and lower lip was established. 8. Tongue posture of post-treatment was more raised than pretreatment. B. Deep bite case 1. The treatment time was 1 year 8 months. 2. Upper incisors showed intrusion and labioversion and lower incisors showed slight intrusion and linguoversion. 3. The lower molars showed distal uprighting and intrusion and upper molars showed mesial movement and extrusion. 4. Normal overbite and overjet were established. 5. Maxilla did not show downward movement. 6. Mandible showed slight clockwise rotation. 7. Lower lip showed retraction and downward drop and upper lip showed downward drop.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.532-542
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• 2007

The purpose of study was to review the transition of dentition according to the evolution of man to know the background of the dental problems like hypodontia and malocclusion. Man is Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Primates, Suborder Haplorrhini, Superfamily Hominoidea, Family Hominidae, Genus Homo, Species Sapiens by taxonomy. The first hominid was Australopithecus which appeared c. 4 millions of years ago and showed bipedalism and distinct dentition. Homos began with H. habilis who appeared c. 2.5 millions of years ago and made stone tools, and then H. erectus and H. neanderthalensis appeared and disappeared until H. sapiens came. The dental formula of primitive mammalians which was I3 C1 P4 M3 changed to I2 C1 P4 M3 of primitive primates, to I2 C1 P3 M3 of Haplorrhini, and to I2 C1 P2 M3 of hominoids. That of H. sapiens is changing to I2 C1 P2 M2.The box type dentition of hominoids changed to the omega type dentition of Australopithecus, and to the parabolic type of H. sapiens. The size of teeth decreased continually, especially the canine and sexual dimorphism. The dentition moved backward and downward to the cranial crown according to the increase of the brain and decrease of the jaws. It was suggested that the change of diet to the starchy foods, food processing, and the development of cooking reduced the necessity of mastication and caused the change of dentition. The future of H. sapiens who is quite a new species in the earth histroy and is now causing the mass extinction of other species is hard to see. It seems that hypodontia and malocclusion are related to the dentition change according to the evolution of man and is likely to increase.

• The Journal of the Korean dental association
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• v.25 no.11 s.222
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• pp.1069-1077
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• 1987

Two brothers aged 15 1/6 and 12 2/3 years were diagnosed as Class I malocclusion with ectopic eruption of the upper left central incisor in the elder brother and etopic eruption in the upper right second premolar in the younger. All 4 second molars were extracted at the same time in both brothers. The treatment results were as follows. 1. In the elder brother, the third molars were fully erupted and their angulations were excellent at 3 years post-treatment. 2. In the younger brother, the lower right third molar was mesially erupted and upper third molars were still undergoing eruption at 3 years post-treatment. 3. Assessment of panex films of both brothers at aged 15 showed an earlier eruption of the third molars in the younger brother. 4. A longer post-treatment supervision of the third molars was required in the younger brother. 5. The facial probiles were enhanced and the ectopic eruptions were corrected in both brothers.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.359-372
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• 1997

This study was conducted to discern differences of craniofacial, dentoalveolar structure and model measurements between sex and between class n openbite group and non-openbite group. The sample consisted of 49 adult patients with class Il malocclusion. 24 linear measurements, 22 angular measurements and 12 ratios were selected in lateral cephalometry. Also, arch width, length, anterior crowding, average molar relation were measured or calculated in diagnostic model. The data were evaluated by t-test and multiple discriminant analysis. The results were as follows, 1. Most linear measurements, with the exception of MnBL and AUDH, were significantly larger in male(p<0.05). but, intermaxillary relations and spatial position of maxilla and mandible relative to cranial base were not different for both sex. 2. With the exception of upper and lower anterior crowding, lower arch width, upper arch length, AMR, male exhibited significantly larger measurements in model analysis (p<0.05). 3. Size differences of maxilla and mandible between openbite and non-openbite group were not significant(p>0.05). but openbite group showed significantly increased genial angle(p<0.05), FH-CoGo(p<0.01), FH-NA(p<0.01) and FH-NB, FH-NPog (p<0.05). 4. ALFH and PUDH were larger(p<0.05) in openbite group. this result served as compensation for the spatial position of mandible relative to cranial base. AUPUDH (p<0.001) and ALPLDH(p<0.05) were lower in openbite group. upper anterior crowding was the only measurement which showed difference between openbite and non-openbite group(p<0.05). 5. For the purpose of classifying adult class n openbite and non-openbite group, multiple discriminant analysis was done genial angle, ALPLDH, AUPUDH, FH-NA were included in multiple discriminant equation. 39 cases($92.86\%$) were correctly classified when applied to the sample used in this study.

• The korean journal of orthodontics
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• v.45 no.2
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• pp.59-65
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• 2015

Objective: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. Methods: A retrospective study of 34 patients (23 men, 11 women; mean age, $26.2{\pm}6.6years$) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. Results: The significant T0 to T1 mandibular changes occurred $-9.24{\pm}3.97mm$ horizontally. From T1 to T2, the mandible tended to move forward $1.22{\pm}2.02mm$, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). Conclusions: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

• The korean journal of orthodontics
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• v.40 no.6
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• pp.383-397
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• 2010

Objective: The objective of this study was to compare maxillary soft tissue changes and their relative ratios to hard tissue changes after anterior segmental osteotomy (ASO)/bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I/BSSRO in skeletal Class III malocclusion with upper lip protrusion. Methods: The study sample comprised the ASO/BSSRO group (n = 14) and the Le Fort I/BSSRO group (n = 15). The Le Fort I/BSSRO group included cases of maxillary posterior impaction only. Lateral cephalograms were taken 2 months before and 6 months after surgery. Linear and angular measurements were performed. Results: The anterior maxilla moved backward in both groups after surgery, however the amount of change was significantly larger in the ASO/BSSRO group (p < 0.01). The ratios of hard to soft tissue change were 79% (SLS to A point), 80% (LS to A point) in the ASO/BSSRO group, and 15% (SLS to A point), 68% (LS to A point) in the Le fort I/BSSRO group. In addition, there was a $3.23^{\circ}$ increase of the occlusal plane in the Le Fort I/BSSRO group. Conclusions: When two-jaw surgery is indicated in skeletal Class III patients with protrusive lips, ASO may be a treatment of choice for cases with more severe upper lip protrusion, while Le Fort I with posterior impaction may be considered if an increase of occlusal plane angle is required.

• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.247-261
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• 1995

The purpose of this study was to quantitate differences in the nature of the correction of Angle's Class II div 1 malocclusion dependent on the patient's age at the time of treatment. The sample consisted of 27 female patients in the adolescent group with a mean initial records age of 11.8 years and 25 female patients in the adult group with a mean starting age of 21.1 yrs. Lateral cephalometric head films were taken before and after orthodontic treatment with four bicuspid extraction. The results were obtained as follows. 1. None of maxillary skeletal parameters exhibited a significantly different in treatment change between adolescents and adults. But, in mandibular skeletal measurements, there were significant differences between two groups. (P<0.05) 2. Measures of vertical dimension in the adults remained unchanged during treatment, reflecting the effective absence of growth. 3. The steepness of occlusal plane in the adults changed significantly.(P<0.05) In contrast, the adolescents displayed stability of the occlusal plane. 4. According to the Johnston analysis, there was a significant difference in the total molar correction between two groups.(P<0.05) 5. According to the Johnston analysis, differential mandibular growth in the adolescents contrubuted $63\%$ of the total molar correction, with orthodontic tooth movement accounting for the remaining $37\%$. In the adults, dental movement comprised $99\%$ of the correction.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.79-89
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• 1997

One of the strenuous problems in orthodontic procedures is postretention stability and retention against relapse. Many investigative trial had been done to disclose the factors associated with relapse and effective prescription to stave off, however, the nature of these jeopardies remained obscure. The objective was to investigate the long-term stability and quantitative changes of dental arches subsequently after Class I nonextraction treatment. Study models,cephalometric headfilms of 26 samples which were taken before, after teatment and postretention were employed to measure the interdental width of corresponding buccal teeth,overbite,overjet and the inclination of incisors and molars. Statistical analysis was carried to compare each measurements across the time period, and followings were brought around. 1. The quantitative amount of relapse in overbite presented positive correlation with the amount of changes through the treatment. 2. Stability of intercanine width was so far secure in the case the expansion had been done through. 3. The amount of changes in intercanine width of the lower regardless of expansion or contraction manifested less than the upper, however, the relapse ratio got high. 4. The upper and lower incisors were likely to be labioversive, and remained stable after retention. 5. The first molars of the upper and lower were conceivably tipped back immediately after treatment and returned to the original angulation. The expansion of intermolar width stayed stable across the time scheme after treatment It was suggested that the maintenance of intercanine width of lower was pertinent to perform the postretention stabilityv and the expansion of dental arch shoed be confined within physiologic boundaries of the patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.2
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• pp.209-218
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• 2019

This study was aimed to evaluate orofacial morphologies on the cases of developmental disorders of maxillary first molars. Panoramic radiographs, lateral cephalographs, and clinical photos of 2983 children who attended the Pediatric Dental Clinic of Pusan National University Dental Hospital from 2006 to August 2017 were assessed retrospectively. 34 patients were selected whose maxillary first molars were missed or developmentally delayed unilaterally or bilaterally. Demirjian's method was used for estimating dental age, then which was compared to chronologic age of children. Parameters expressing skeletal and dentoalveolar disharmony were checked and compared with control. Additionally, occlusion relationship was evaluated. Maxillary dental age was significantly delayed compared to chronologic age. Several parameters which show skeletal open-bite tendency and skeletal class III malocclusion with maxillary retrusion were statistically significant. Anterior crossbite and edge-bite were expected in most of these cases, but compensation by occlusion and soft tissue was also verified which might mask skeletal class III tendency. Congenital missed or developmentally delayed maxillary first molars might be related with declined growth of maxilla. If developmental disorders of maxillary first molars were verified during clinical examination, careful monitoring of orofacial growth was necessary during puberty and timed orthopedic and orthodontic intervention were considered.