• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.2
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• pp.201-210
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• 1990

The purpose of this study was to observe the relationship between mandibular asymmetry and Temporomandibular Disorders by means of the cephalometry using the posteroanterior cephalogram and the submentovertex cephalogram which were taken in 35 Temporomandibular Disorder patients and 35 normal persons ranged from 20S to 30S. The results were as follows: 1. The angulation which was formed by the median line with the ANS-Menton line (MAP) was greater in patients group and there was statistically significant difference. 2. The angulation which was formed to the median line with the Menton-Odontoid process tip line (MES), the difference of the distances from the center of the posterior surface of the both condyles to the most anterior point of the chin (DD), the difference of the distances from the center of the both condyles to the horizontal reference line (DE), the difference of the angulations which were formed by the both condyles axes with the horizontal reference line (DCE), the difference of the lengths of the both condyles (CL) and the difference of the widths of the both condyles (DW) were greater in patients group and there were statistically significant differences. There was reversed correlation between MAP and the difference of the distances from the 3. bilateral points of the lateral margin of the both zygomaticofrontal sutures to the at the lateral inferior margin of the both antegonial protuberances in mandible (DH). There was reversed correlation between MES and DD, DE, DCE. 5. There was correlation between MAP and MES.

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.317-325
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• 1999

In proper diagnosis of skeletal Class III malocclusion, it was important to know the pattern of three dimensional skeletal & facial disharmony. The purpose of this study was to obtain P-A cephalometric characteristics in skeletal Class III malocclusion comparing with normal occlusion. The samples were consisted of 120 subjects, divided into four groups : Male normal occlusion, Female normal occlusion, Male skeletal Class III malocclusion, Female skeletal Class III malocclusion. Posteroanterior and lateral cephalogram were taken from the subjects with a x-ray apparatus (ASHAI CX90SP, Japan) and traced on acetate paper with routine manner. The transverse and vertical values from posteroanterior cephalometry, the sagittal values from lateral cephalometry and their ratio were obtained. The results were as follows: 1. The anteroposterior discrepancy in skeletal Class III group was not due to short maxillary length(Cd-A), but to longer mandibular length(Cd-Gn) than normal occlusion group. 2. The faces of skeletal Class III group were longer than normal occlusion group. It was not due to increase of upper face height(Cg-ANS) but to increase of the lower face height(ANS-Me) especially mandibular height(Cd-Me). 3. There was no difference in the facial width values between normal occlusion group and skeletal Class III group, except upper molar width(U6-U6), lower molar width(L6-L6) and mandibular width(Ag-Ag) of female skeletal Class III group which were larger than normal occlusion group. 4. The increase of mandibular length of skeletal Class III group was reflected in the increase of lower facial height but did not have an effect on the mandibular width.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.3
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• pp.125-134
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• 2023

Objectives: The aim of the study was to quantify and compare craniofacial asymmetry in subjects with and without symptoms of temporomandibular joint disorders (TMDs). Materials and Methods: A total of 126 adult subjects were categorized into two groups (63 with a TMDs and 63 without a TMDs), based on detection of symptoms using the Temporomandibular Joint Disorder-Diagnostic Index (TMD-DI) questionnaire. Posteroanterior cephalograms of each subject were traced manually and 17 linear and angular measurements were analyzed. Craniofacial asymmetry was quantified by calculating the asymmetry index (AI) of bilateral parameters for both groups. Results: Intra- and intergroup comparisons were analyzed using independent t-test and Mann-Whitney U test, respectively, with a P<0.05 considered statistically significant. An AI for each linear and angular bilateral parameter was calculated; higher asymmetry was found in TMD-positive patients compared with TMD-negative patients. An intergroup comparison of AIs found highly significant differences for the parameters of antegonial notch to horizontal plane distance, jugular point to horizontal plane distance, antegonial notch to menton distance, antegonial notch to vertical plane distance, condylion to vertical plane distance, and angle formed by vertical plane, O point and antegonial notch. Significant deviation of the menton distance from the facial midline was also evident. Conclusion: Greater facial asymmetry was seen in the TMD-positive group compared with the TMD-negative group. The mandibular region was characterized by asymmetries of greater magnitude compared with the maxilla. Patients with facial asymmetry often require management of temporomandibular joint (TMJ) pathology to achieve a stable, functional, and esthetic result. Ignoring the TMJ during treatment or failing to provide proper management of the TMJ and performing only orthognathic surgery may result in worsening of TMJ-associated symptoms (jaw dysfunction and pain) and re-occurrence of asymmetry and malocclusion. Assessments of facial asymmetry should take into account TMJ disorders to improve diagnostic accuracy and treatment outcomes.

• Archives of Plastic Surgery
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• v.34 no.5
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• pp.635-640
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• 2007

Purpose: Mid and lower facial convexity is more common in Oriental people than in Caucasian. Bimaxillary dentoalveolar protrusion is characterized by procumbent teeth, protruding lips, acute nasolabial angle, gummy smile, receding chin, facial convexity. Especially, pure maxillary dentoalveolar protrusion is less frequent than bimaxillary dentoalveolar protrusion. Therefore, it is important to make an accurate decision for the operation throughout the history taking, cephalogram, dental cast to arrive at accurate diagnosis and surgical plan. Methods: From December 2002 to June 2004, ten patients with maxillary dentoalveolar protrusion and microgenia were corrected by maxillary anterior segmental osteotomy and advancement genioplasty. 10 patients were analyzed by preoperative and postoperative clinical photography, posteroanterior and lateral cephalograms. Results: No major complications were occurred throughout the follow-up period except one of the over-recessed, otherwise most of the patients were satisfied with the result. Conclusion: We could correct the occulusal relationship with teeth and improve lower facial profile, asthetically and functionally, by maxillary anterior segmental osteotomy and advancement genioplasty.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.4
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• pp.337-345
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• 2011

Purpose: The purpose of this study was to define the relation of the degree of menton deviation and 3-D CT (computerized tomography) measurements of the glenoid fossa and the mandible, which are considered to have an influence on menton deviation. Methods: The CT images were obtained in 60 adults and these were transmitted to a computer and reconstructed using computer software. According to the degree of the menton deviation, which was measured on the posteroanterior cephalogram, the subjects were divided into the menton deviated group (30 adults) and the symmetry group (30 adults). A total of 11 measurements that might have an effect on menton deviation were determined and these were measured in the right and left sides using the function of 3-D measurement in the computer program. The 11 measurements consist of 6 measurements in the glenoid fossa (vertical position of the glenoid fossa and articular eminence, the sagittal position of the glenoid fossa and articular eminence, the depth of the glenoid fossa, and the anterior angle of the glenoid fossa), and 5 measurements in the mandible (ramus length, frontal ramal inclination, lateral ramal inclination, body length, body height). Results: The comparison of the differences between the menton deviated and symmetry groups and correlation analysis on the degree of menton deviation were carried out. The results of comparison of the right and the left difference between the menton deviated and symmetry groups showed that the vertical position and depth of the glenoid fossa were significantly increased in the menton deviated group. Conclusion: The results of the present study show that consideration of the shape and position of the glenoid fossa is necessary for making the diagnosis and administering proper treatment in facial asymmetry patients and especially growing patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.594-606
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• 1996

This study was intended to perform the relationships between mandibualr lateral deviation in facial asymmetry patients and morphology of the cranial vault. In 30 patients(males 14, female 16) using submento-vertical cephalograms that were taken in the pre-operaticve state and posteroanterioir cephalograms that were taken in centric occlusion before, immediate and long term after surgery. 1. Mean mandibular deviation was about $-3.12^{\circ}$and mean of absolute measurement was about $2.50^{\circ}$on the submento-vertical cephalograms. 2. On the submento-vertical cephalograms, there was no significant difference between non-deviation and deviation side but it had tendency that deviation side was larger than non-deviation side on the frontal portion of cranium(Y10 to Y6) and deviation side was smaller than non-deviation on the temporal portion of cranium(Y5, Y-1 to Y-5). 3. Mean mandibular deviation was about $1.40^{\circ}$and mean of absolute measurement was about $3.95^{\circ}$on the posteroanterioir cephalograms. 4. There was statistical significance on the influence of surgical change(PT2A-PT1A) to the relapse(PTLA-PT2A)(p<0.05). The more increasing of the change, the more relapse on the posteroanterioir cephalograms. 5. There was no statistical significance on the influence of degree of mandibular deviation to morphology of the cranium on the submento-vertical cephalograms. But it had tendency that the more mandibular deviation, the larger the non-deviation side on the anterior cranium and deviation side on the posterior cranium(p>0.05). 6. There was statistical significance on the influence of the degree of mandibular deviation on the posteroanterioir cephalograms to the difference between non-deviation and deviation side. The more increasing of mandibular deviation, the larger the non-deviation side on the Y4 to Y-6(p<0.05). 7. There was no statistical significance on the influence of difference between non-deviation and deviation side to the relapse on the posteroanterioir cephalograms. But it had tendency that the more increasing of the differece between non-deviation and deviation side, the more increasing the relapse on temporal of cranium.

• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.311-321
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• 1995

This study was undertaken to investigate the distribution of the chewing side preference and variations in the maximum bite force and facial morphology according to chewing side preference since unilateral chewing may cause morphologic and functional anomalies. 50 dental students who had no signs or symptoms of masticatory system and Angle's Class I relationship in posterior segments were selected, and divided into two groups, that is, 25 in bilateral chewing group(19 male and 6 female) and 25 in unilateral chewing group(10 male and 15 female). Maximum bite force was estimated ana posteroanterior cephalogram were measured ana statistically analyzed. The results were as follows : 1. Their were more students with bilateral chewing side preference($68\%$) and unilateral chewing side group consisted of right side preference($68\%$) and left side preference($32\%$). 2. There was no significant difference in the strength of max. bite force between the right and left side in bilateral chewing group. The bite force of the chewing side nab greater in the unilateral chewing group but less in the non-chewing side compared to those of bilateral chewing group with Bo significant difference. Max. bite force of chewing side was greater than that of non-chewing side in the unilateral chewing group(Female p<0.05). Max. bite force of males was about twice in that of females in both groups(p<0.05). Max. bite force of chewing side of the unilateral chewing group was similar to that of the bilateral chewing group, but that of non-chewing side was less than that of the bilateral chewing group. 3. In comparison of the facial morphology, there was no statistically significant difference in the size between the right and left side of the bilateral chewing group and between chewing and non-chewing side of the unilateral chewing group.