• 대한치과교정학회지
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• 제18권1호
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• pp.209-216
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• 1988

The purpose of this study was to verify the class I molar relationship in skeletal class II and class II molar relationship in skeletal clan I malocclusion with unilateral class II, division 1 malocclusion. The sample consisted of lateral cephalometric radiographs and upper and lower dental casts of 30 unilateral class II, division 1 malocclusion. The results of this study were as follows: 1. Skeletal class I malocclusion was $43\%$, and skeletal class II malocclusion was $57\%$ in 30 cases of unilateral class II, division 1 malocclusion. 2. In the skeletal class II with unilateral class II, division 1 malocclusion, mandibular first molar on the class I side showed more mesial migration than the opposite side. 3. In the skeletal class I with unilateral class II, division 1 malocclusion, maxillary first molar on the class II side showed more mesial migration than the opposite side. 4. Midline deviation of upper or lower dental arch was $90\%$ in 30 cases of unilateral class II, division 1 malocclusion.

• 대한치과교정학회지
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• 제20권1호
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• pp.111-122
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• 1990

To investigate the relationship of skeletal maturity among the normal occlusion group and each malocclusion groups, the author used hand and wrist X-ray of 133 Korean 13 year old boys (normal occlusion 30, Class I malocclusion 35, Class II malocclusion 35 and Class III malocclusion 33) and assessed their skeletal maturity. In this study, fourteen skeletal maturity stages were selected from; Radius, Hamate, Pisiform, Ulnar sesamoid of the metacarpophalangeal joint of the first thumb, proximal phalanges of the first, second and third finger, middle and distal phalanx of the third finger. The difference of skeletal maturity of each malocclusion groups in relative to normal occlusion group and that of each malocclusion groups were analyzed. The findings of this study can be summerized as follows: 1. Average skeletal maturity stage of each groups were MP3cap stage in normal occlusion group, H-2 stage in Class I malocclusion group, midstage between S and H-2 stage in Class II malocclusion group, MP3cap stage in Class III malocclusion group. 2. There was no significant difference in skeletal maturity of Class I malocclusion and Class III malocclusion groups in relative to normal occlusion group. 3. There was significant retardation of skeletal maturity in Class II malocclusion group in relative to normal occlusion group. 4. There was no significant difference in skeletal maturity between Class I and Class II malocclusion groups. 5. There was no significant difference in skeletal maturity between Class I and Class III malocclusion groups. 6. There was significant retardation of skeletal maturity in Class II malocclusion group in relative to Class III malocclusion group.

• 대한치과교정학회지
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• 제16권1호
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• pp.107-118
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• 1986

This study was designed to investigate the variation of mandibular pattern and cranial base and their association in the craniofacial malocclusion. The material was the 165 cephalometric radiographs taken from craniofacial malocclusion. The sample was devided into two groups by age child group aged from 10 to 13 years and adult group aged over 18 years, and each group was devided into 3 types of malocclusion; class I, Class II div. 1 and Class III malocclusion. Child group consist of 35 samples and adult group consist of 20 samples in each malocclusion type. Various angular and linear measurements on the cephalometric radiographs were recorded and statistically analyzed. The results of the study were as follows; 1. The cranial base angle was largest in Class II div. 1 malocclusion and smallest in Class III malocclusion 2. The anterior cranial base length was largest in Class II div. 1 malocclusion but posterior cranial base length did not show statistical difference. 3. The mandibular body length of Class III malocclusion was larger than those of Class I and Class II div. 1 malocclusion in the adult group but did not shown difference in the child group. The ramus height of Class III malocclusion was larger than those of Class I and Class II div. 1 malocclusion in the child and adult group, but there were no difference between Class I and Class II div. 1 malocclusion. 4. The mandibular position was showed low correlation with the cranial base angele.

• 대한치과교정학회지
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• 제14권1호
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• pp.33-37
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• 1984

The prevalence of normal occlusion and malocclusion was assessed by Angle's Classification method for 8989 school students at 7-22 years in Seoul. The occurrence of malocclusion and the need-for orthodontic treatment was 61 per cent among them. Results indicated no significant differences between the sexes for the occlusal relationships of the mandible to the maxille. The prevalence of Class I, Class II, and Class III malocclusion in all malocclusion was shown to be Class I, 45.7 per cent; Class II, 7.6 per cent; and Class III, 7.9 per cent. Class II Division 1 was observed to occur four times frequently compared to Class II Division 2 in Class II malocclusions. Class III malocclusion was shown to occur more frequently compared that of Caucasians.

• 대한치과교정학회지
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• 제18권1호
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• pp.141-154
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• 1988

This study was designed to investigate the difference between craniofacial characteristics of the normal occlusion and those of Class II Div. 1 malocclusion. The sample was divided into 2 groups, the 50 subjects of Normal occlusion, the 50 subjects of Class II Div. 1 malocclusion in both sexes. Both groups aged from 11 to 14 years. The results of this study were as follows; 1. No significant difference was observed in cranial base shape between both groups, but anterior cranial base size of Class II Div. 1 malocclusion group was larger than that of normal group. 2. No significant difference in antero-posterior position of Maxilla to cranial base was founded between both groups. 3. No difference in Mandibular shapes and Mandibular plane angles to the cranial base was observed between Class II Div. 1 malocclusion and normal occlusion, but Mandibular position in Class II Div. 1 malocclusion was posterior to that of normal group. 4. Antero-posterior relationship of Maxilla and Mandible was significant difference between both groups, but vertical relationship of those was no difference. 5. Maxillary incisor position to cranial base of Class II Div. 1 malocclusion was anteior to normal occlusion, and Maxillary posterior teeth was posterior. Mandibular incisor and mandibular posterior teeth position was no difference. 6. Upper and lower lip position to esthetic line of Class II Div. 1 malocclusion was anterior to normal occlusion.

• 대한치과교정학회지
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• 제10권1호
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• pp.45-53
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• 1980

This study was based on the study models of 32 subjects with normal occlusion, 40 with Class I malocclusion, 32 with Class II, Division 1 malocclusion and 38 with Class III malocclusion, aged 12 to 20 years (mean age 16.4 years). The purpose of present study was to define the difference between normal and malocclusion groups in maxillary dental arch and palate. On the basis of findings of this study, the following results were obtained. 1. The intermolar widths and the intercanine widths in Class II, Div. 1 malocclusion group were smaller than in normal occlusion group significantly. 2. The arch lengths measured in both Class I and Class II, Div.1 malocclusion groups were larger than in normal occlusion group. 3. The palates in Class I and Class II, Div. 1 malocclusion groups were longer and narrower than in normal occlusion, but the palates in Class III malocclusion group were shorter than in normal occlusion group significantly. 4. The palatal depths measured at level 1 in Class III malocclusion group were significantly higher than in normal occlusion and in Class II, Div. 1 group they were significantly higher than in normal occlusion at level 2 and 3. 5. The measurements of palatal areas at various levels showed no significant difference between malocclusion and normal occlusion groups. 6. The palatal indies 1 (palatal length / palatal width) measured in both Class I and Class II, Div. 1 malocclusion groups were significantly greater than in normal occlusion and the palatal indice 2 (palatal depth at level 1/palatal width) measured in all malocclusion groups are greater than in normal occlusion. 7. It was determined from findings of this study that the measurements of maxillary dental arch and palate were influenced to a considerable extent by the molar relationship.

• 대한치과교정학회지
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• 제19권3호
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• pp.67-78
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• 1989

This study was designed to investigate the difference of teeth and craniofacial complex between normal occlusion and Angle's Class II, div. 1 malocclusion in Korean children. The sample was divided into 2 groups, the 66 subjects with normal occlusion and 96 subjects with Angle's Class II, div. 1 malocclusion in both sexes. The results obtained were as follows: 1. No significant differences were observed in ant. cranial base length & cranial flexure (saddle) angle) between normal occlusion & Angle's Class II, div. 1 malocclusion group, but posterior cranial base length of Class II, div. 1 malocclusion group was larger than that of normal occlusion group. 2. No significant difference was observed in the anteroposterior position of Maxilla to cranial base between two groups, but mandibular position in Class II, Div. 1 malocclusion was posterior and interior to that of normal occlusion. 3. The length of maxilla (ANS-PSN) was larger in Class II, div. 1 malocclusion than normal occlusion. The length of mandibular body (Go-Me) was nor different between Class II, div. 1 malocclusion and normal occlusion. 4. Maxillary incisor position of Class II, div. 1 malocclusion to cranial base was more protrusive than that of normal occlusion, but there was no difference in mandibular incisor position between two groups.

• 대한치과교정학회지
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• 제10권1호
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• pp.15-27
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• 1980

This study was undertaken to compare the craniofacial morphology of Class II, Division 1 malocclusion with that of normal occlusion in children, and to investigate the incidence of various Class II, Division 1 craniofacial skeletal patterns. The subjects consist of thirty seven boys and fifty three girls with Class II, Division 1 malocclusion, and forty six boys and eighty one girls 10-15 years with normal occlusion. Measurements were recorded, tabulated and analyzed on the lateral cephalograms by the degree of SNA, SNB and ANB. The following characteristics of the Class II, Division 1 skeletal pattern were observed. 1. The anteroposterior relationship of the maxilla to the cranium in the Class II, Division 1 was very similar to that of normal occlusion. 2, Mandible of the Class II, Division 1 malocclusion was in the posterior position in relation to the cranial anatomy when compared to normal. 3. The chin point as measured by SN Pog and NS Gn showed distal positioning in relation to normal occlusion. 4. SN to mandibular plane angle was large in Class II, Division 1 malocclusion. 5. Mandibular incisor inclination was not significantly different between Class II, Division 1 malocclusion and normal occlusion, but maxillary incisors inclined and positioned labially and consequently overjet was large in Class II, Division 1 malocclusion. 6. Class II, Division 1 malocclusion was divided into four types of craniofacial skeletal pattern. The most common Class II, Division 1 pattern was found to be type C in which SN-Mand. Pl. was above mean range of normal occlusion. The next frequent pattern was found to be type A in which maxilla and mandible were within normal range of protrusion while upper incisors were severly labially inclined.

• 대한치과교정학회지
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• 제47권3호
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• pp.151-157
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• 2017

Objective: The objective of this study was to investigate the differences in masticatory efficiency among patients with different Angle's classes of malocclusion and to assess the correlation between masticatory efficiency and the occlusal contact area. Methods: The mixing ability index (MAI) was calculated for measuring masticatory efficiency of 61 adult patients according to Angle's classifications of malocclusion. The study included 25, 15, and 21 patients with Angle's Class I, II, and III malocclusions, respectively. Silicone interocclusal recording material was used to measure the occlusal contact area. Results: Both the MAI and occlusal contact area showed the highest average values in the Class I malocclusion group, followed by the Class II and Class III malocclusion groups. No significant difference was observed in the MAI values between the Class I and Class II malocclusion groups (p > 0.05), whereas a significant difference was observed between the Class I and Class III malocclusion groups (p < 0.01) and between the Class II and Class III malocclusion groups (p < 0.05). A weak positive correlation was also observed between the MAI and occlusal contact area (p < 0.01, $r^2=0.13$). Conclusions: The results of this study indicated that masticatory efficiency was the highest in patients with Angle's Class I malocclusion, followed by those with Angle's Class II and Angle's Class III malocclusions. Moreover, a weak positive correlation was observed between masticatory efficiency and the occlusal contact area.

• 대한심미치과학회지
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• 제4권1호
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• pp.23-36
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• 1995

The purpose of this artic1e is to compare soft tissue profiles between Korean adults with normal occ1usion and malocclusin and to identify the differences between them. The subjects of this cephalometric study were 40 males with normal occlusion(Group 1), 27 females with normal occlusion(Group 2), 28 adults with Angle's Class II malocclusion(Group 3) and 41 adults with Angle's Class III malocclusion(Group 4). The results of this study were as follows ; 1) People with Angle's Class II malocclusion had tendency to have more labial tipping of lower teeth than people with normal occ1usion. Through NOA angle measurement, it was determined that people with Angle's Class II malocclusion had more protruding midface than people with normal occlusion and people with Angle's Class III malocclusion had retruding midface. 2) Through Powell's esthetic triangle analysis, it was determined that people with Angle's Class II malocclusion had retruding chin and protruding nose. 3) No significant differences between people with normal occlusion and maloclusion could be identified by measuring soft tissue profile angle basis of S-NS plane. 4) There were significant differences between groups with normal occlusion and malocclusion by measuring Facial convexity angle(Significance level 99%). 5) By measuring the distance between each landmark basis of N-Pog plane, People with Angle's Class II malocclusion were identified as having more protruding midface, but there were no significant differences between people with normal occlusion and Angle's Class III malocclusion. 6) By measuring the vertical dimension of the face, it was determined that the lower facial height was higher than the upper facial height in all groups, particularly in group with Angle's Class III malocclusion. 7) By measuring the lips basis of E-line and S-line, it was determined that people with Angle's Class III malocclusion had more, protruding lower lips than people with normal occlusion, while people with normal occlusion, while people with Angle's Class II malocclusion had more protruding upper lips. By measuring the distance between the superior sulcus and inferior sulcus basis of H-line, people with Angle's Class II malocclusion had thicker upper lips than the other's.