• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.303-315
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• 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
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• v.28 no.5 s.70
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• pp.763-774
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• 1998

The purpose of this study was to evaluate the morphology of mandibular symphysis and location of lower incisor under the influence of the craniofacial skeleton in skeletal Class III malocclusion. The sample consisted of 132 adults who have severe Class III malocclusion(prognathism group, 33 males and 33 females), and who have normal occlusion(normal group, 33 males and 33 females). They had not received any orthodontic treatment or orthognathic surgery. The lateral cephalograms were evaluated. The results were as follows : 1. Prognathism group were larger than normal group in comparison of facial skeleton (p<0.05) with the exception of ${\angle}FH-Pal$, ${\angle}SNA$. 2. In the morphology of symphysis, measurements of anteroposterior width(LaABBW, LiABBW, SW) of prognathism group were significantly less than that of normal group(p<0.001). 3. In the correlative analysis between the craniofacial skeleton and symphysis measurements of prognathism group, vertical measurements in relation with cranial base and mandibular plane showed reverse correlationship with anteroposterior width of symphysis(LiACBW, LaACBW, LiABBW, SW)(p<0.05). But, there was not distinct difference between horizontal skeletal measurements and symphysis measurements(p>0.05). 4. The probability by regression test between vertical measurements(${\angle}SN-Mn,\;{\angle}FMA,\;{\angle}Pal-Mn,\;{\angle}LFH$) and symphysis measurements(LiACBW, LiABBW, SW, ${\angle}LISA$) were very high(p<0.001).

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.601-611
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• 1996

Craniofacial growth pattern is an important diagnostic data in the course of orthodontic diagnosis and treatment planning ; it also has great influence in the establishment of occlusion as well as shaping and development of face. There have been many studies to classify different craniofacial growth patterns and attempts to predict growth patterns. This study aimed to correlate craniofacial growth pattern and symphysis morphology. 120 adult patients with age from 19 to 39 (mean age : 23.1) were chosen as subjects , using lateral cephalometric films. their anterior to posterior facial height ratios were calculated. They were divided into 3 groups - clockwise growth pattern with $56\%-62\%$(36subjects), counter-clockwise growth pattern group with $65\%$-80\%$(43subjects) and normal growth pattern group with $62\%-65\%$(41subjects). Symphysis morphology and Prominence evaluation in each subject were studied and the following conclusions were drawn : 1. In comparison of symphysis morphology between the sex groups, men showed large symphysis height and prominence. 2. Concerning the symphysis morphology, the clockwise growth pattern group showed larger height, H/D ratio and actual length but smaller depth, angle, effective length and E/A ratio compared to the counter -clockwise growth pattern group. 3. Those with smaller prominance of symphysis showed clockwise growth tendency and those with larger prominance showed counter-clockwise growth tendency.

• The korean journal of orthodontics
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• v.32 no.5 s.94
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• pp.361-373
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• 2002

The purpose of this study was to evaluate the morphological changes of olveolar bone and mandibular symphysis of lower incisor by presurgical orthodontic treatment and orthognathic surgery in skeletal class III malocclusion. The sample consisted of 30 adult class III malocclusion patients who have received bilateral sagittal split mandibular osteotomy. Lateral cephalograms were taken before treatment, after presurgical orthodontic treatment and 3 months after orthognathic surgery. Skeletal and symphyseal measurements were compared and the relationships between them were analysed. The results were as follow : 1. The labial and lingual alveolar bone height in presurgical and postsurgical group were decreased than that of pretreatment group. 2. The vertical measurements of the craniofacial skeleton showed reverse correlationship with anteroposterior width of basal alveolar bone, but IMPA showed correlatiionship (p<0.01) 3. The craniofacial skeleton and the change of symphyseal measurements(symphyseal length, symphyseal width) showed no correlationship. 4. The labial alveolar bone height showed correlationship with lingual alveolar bone height(p<0.001), and negative correlationship with lingual alveolar crestal width(p<0.01). Labial and lingual alveolar crestal width has negative correlationship (p<0.05). Mandibular symphyseal length and width has positive correlationship(p<0.01). 5. IMPA, LISA showed negative correlationship with labiolingual alveolar bone height and lingual alveolar width and positive correlationship with labial alveolar base bone width.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.119-127
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• 1997

The configuration of mandibular symphysis is likely to be dependent upon the genetic predeterminants and/or compensatory adjustments onto functional demands. The interrelation of morphological distinctives of symphysis in conjunction to the craniofacial skeleton had been scarcely anecdotal, therefore, the objective was to determine the correlation of morphological modifications between the mandibular symphysis and craniofacial complex. Lateral cephalometric headfilms of 212 subjects were employed for the conventional measurements. The proportion of chin height against chin depth length was referred as chin ratio, then, Low Symphysis (IS) and High Symphysis (HS) groups were turned out by means of the chin ratio. These samples yielded 35 in LS and 35 in HS groups. The data per capita were statistically analyzed and the following results were drawn ; 1. Overall characteristics of the craniofacial skeleton in HS group manifested hyperdivergence and LS group showed hypodivergence. 2. Gonial angle increased as chin ratio increased and was highly correlated to the chin ratio. 3. The chin ratio presented high correlation to the vertical face height, especially in terms of the chin height to anterior face height and the chin depth to posterior face height. 4. The morphological configuration of chin was hardly correlated with hyoid bone position.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.135-156
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• 1990

This study was undertaken to investigate the difference of chin morphology and mandibular form in relation to different mandibular growth direction. The subject was divided into three group i.e., control group, vertical group, and horizontal group, according to the criteria of $Bj{\ddot{o}}rk$ sum, and each group was composed of 15 females and 15 males. Medial axis analysis in addition to the routine cephalometric analysis using P.I.A.S. (personal image analysing system) was carried out to find out the differences of mandibular morphology on each group. The results were as follows: 1. The area of symphysis was larger in horizontal growth group than that of vertical growth group. 2. Protruding chin area was also larger in horizontal growth group than that of vertical growth group. 3. There was a close correlationship between protruding chin area and other form of mandible. 4. Antegonial notch depth and ramus posterior contour depth was deeper in vertical growth group than in horizontal growth group, and antegonial notch depth was more influenced by anterior part of notch than posterior part of notch. 5. Mental medial axis and incisal medial axis length, in relation to corpus medial axis length was larger in vertical growth group than in horizontal growth group.