• The Journal of the Korean dental association
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• v.11 no.2
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• pp.134-138
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• 1973

The author measured and analyzed the condyle path inclinations of 25 normal Korean adults roentgeno-cephalometrically and following conclusions were obtained. In protrusive movement of mandible, the angle of condyle pation inclination in relation to 1) occlusal plane is 19.86±8.25, 2) Frankfort Horizontal plane is 28.32±8.56, 3) Camper line is 12.22±4.06, 4) Nasion-sella line is 36.80±8.54.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.2
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• pp.219-225
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• 1990

Panoramic radiography is convenient in clinic and visualizes those areas which other technique do not give. But the technique has limitation of image distortion which results from the relationship of the ramus to the focal trough and from the direction of the central ray. This study is, using 7 dry skulls, to determine the effect of rotation of patient's head on reducing those distortion and determine the magnification ratio of images of mandibular condyle in rotated patient head position. The obtained results were as follows: 1. Generally, in panoramic radiography the anterolateral portion of the mandibular condyle was best to be visualized. 2. There are no significant difference between the image readability of anteromedial portion and that of anterocentral portion of the mandibular condyle. 3. Anterolateral portion of the mandibular condyle was better visualized in rotated head position by 20 degree or horizontal condylar inclination than in conventional position or in rotated head position by 10 degree. 4. The magnification ratio of the anteroposterior diameter in the image of mandibular condyle was least in the rotated head position by horizontal inclination of the mandibular condyle and was largest by 20 degree.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.111-118
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• 2003

I measured the movement range on the hinge articulator and the movement range in an oral. And then I studied to analyze the gap. I got wax records by the movement on the hinge articulator, the movement in an oral and the movement on the hand articulating. I measured the distance of the cusp tips that are close to the mesial direction and the distal direction, the buccal direction and the lingual direction then I compared gaps. As I saw results on data, I knew that the hinge articulator represented the range of mandibular movement restrictively. I could find the decisive contradiction that the sliding movement finished on the hinge articulator although it did not finish in an oral. If the sliding movement does not reappear exactly, it brings a fatal failure to the dental prosthesis. In addition it is impossible that the hinge articulator restores the movement in an oral because the lateral condyle inclination and the horizontal condyle inclination are fixed previously. Therefore dental prosthesisses were made by the hinge articulator, they will interfere with a mastication. I have obtained the following results; 1. The distance of sliding movement on the hinge articulator showed shorter than the distance of sliding movement in oral. This means the increase of cusp inclination of the dental prosthesis that was made on the hinge articulator. Therefore, when the lateral movement occurs in oral, there is a possibility to become the premature as the increase of cusp inclination. 2. The results that were impressed records in oral and impressed records on the hand articulating have many congruities. I think that the simple crown etc. that were made by the hand articulating method except the long span bridge and the free end case that can not measure the vertical dimension exactly can represent similarly the mandibular movement. 3. If we want to represent the mandibular movement similarly, we have to use the articulator that can adjust the horizontal condyle inclination and the lateral condyle inclination at least.

• Journal of Technologic Dentistry
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• v.28 no.1
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• pp.53-59
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• 2006

The movement range on the semi adjustable articulator and the movement range in an oral were measured. And then I studied to analyze the gap. I got wax records by the movement on the semi adjustable articulator, the movement in an oral. I measured the distance of the cusp tips that are close to the mesial direction and the distal direction, the buccal direction and the lingual direction then I compared gaps. As I saw results on data, I knew that the semi adjustable articulator represented the range of mandibular movement restrictively. I could find the decisive contradiction that the sliding movement finished on the semi adjustable articulator although it did not finish in an oral. When the sliding movement does not reappear exactly, it brings a fatal failure to the dental prosthesis. In addition it is impossible that the semi adjustable articulator restores the movement in an oral because the lateral condyle inclination and the horizontal condyle inclination are appeared to be straight. Therefore dental prosthesisses were made by the semi adjustable articulator, they will interfere with a mastication. I have obtained the following results; 1. The distance of sliding movement on the semi adjustable articulator showed shorter than the distance of sliding movement in oral. This means the increase of cusp inclination of the dental prosthesis that was made on the semi adjustable articulator. Therefore, when the lateral movement occurs in oral, there is a possibility to become the premature as the increase of cusp inclination. 2. The difference in the range of movement is considered as the gap that is made because the movement only can be occurred as straight in the semi adjustable articulator. 3. When the dental technician understand mandibular movement and articulator deficiencies, they can attain proficiency in use of the articulator and reduce the gap.

• Imaging Science in Dentistry
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• v.46 no.2
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• pp.127-131
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• 2016

Purpose: This study was performed to compare the condylar position in patients with temporomandibular joint disorders (TMDs) and a normal group by using cone-beam computed tomography (CBCT). Materials and Methods: In the TMD group, 25 patients (5 men and 20 women) were randomly selected among the ones suffering from TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The control group consisted of 25 patients (8 men and 17 women) with normal temporomandibular joints (TMJs) who were referred to the radiology department in order to undergo CBCT scanning for implant treatment in the posterior maxilla. Linear measurements from the superior, anterior, and posterior joint spaces between the condyle and glenoid fossa were made through defined landmarks in the sagittal view. The inclination of articular eminence was also determined. Results: The mean anterior joint space was 2.3 mm in the normal group and 2.8 mm in the TMD group, respectively. The results showed that there was a significant correlation between the superior and posterior joint spaces in both the normal and TMD groups, but it was only in the TMD group that the correlation coefficient among the dimensions of anterior and superior spaces was significant. There was a significant correlation between the inclination of articular eminence and the size of the superior and posterior spaces in the normal group. Conclusion: The average dimension of the anterior joint space was different between the two groups. CBCT could be considered a useful diagnostic imaging modality for TMD patients.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.18 no.1
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• pp.167-176
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• 1988

This study was designed to evaluate the morphology of the temporomandibular joint components and dentofacial characteristics of patients with clicking and painful temporomadibular joint. The materials consisted of 80 conventional pantomographs in normal an symptomatic individuals aged 18-23 and divided into 2 groups by symptom of temporomandibular joint. The results were as follows; 1. In morphologic analysis of condylar head, type Ⅰ (anterior, posterior smooth curve) was most dominant in both group(58.75%, 55.0%) and asymmetrical condylar shape was predominant in symptomatic group (18 cases, 45%). 2. In symptomatic group, the condylar width were slightly lesser and the ratio of condylar height to height of condyle-ramus were larger than those of normal group. 3. Vertical overlap of central incisor of symptomatic group was slightly larger than that of normal group. There was significant differences between each group in mandibular midline deviation. 4. The symptomatic group tended to steep mandibular plane angle and the degree of condylar path and condylar axis of normal group were larger than those of symptomatic group. 5. The condylar width was inversely correlated with inclination of condylar path and inclination of condylar path was correlated with condylar axis in both groups.

• The korean journal of orthodontics
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• v.43 no.4
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• pp.168-177
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• 2013

Objective: In this study, we aimed to examine the relationship between chin deviation and the positional and morphological features of the mandible and to determine the factors that contributed to chin deviation in individuals with a unilateral cleft lip and palate (UCLP). Methods: Cone-beam computed tomography (CBCT) images of 28 adults with UCLP were analyzed in this study. Segmented three-dimensional temporomandibular fossa and mandible images were reconstructed, and angular, linear, and volumetric parameters were measured. Results: For all 28 individuals, the chin was found to deviate to the cleft side by 1.59 mm. Moreover, among these 28 individuals, only 7 showed distinct (more than 4 mm) chin deviation, which was toward the cleft side. Compared to the non-cleft side, the mandibular body length, frontal ramal inclination, and vertical position of the condyle were lower and inclination of the temporomandibular fossa was steeper on the cleft side. Furthermore, the differences in inclination of the temporomandibular fossa, mandibular body length, ramus length, and condylar volume ratio (non-deviated/deviated) were positively correlated with chin deviation. Conclusions: UCLP individuals show mild chin deviation to the cleft side. Statistical differences were noted in the parameters that represented positional and morphological asymmetries of the mandible and temporomandibular fossa; however, these differences were too small to indicate clinical significance.

• The korean journal of orthodontics
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• v.47 no.5
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• pp.277-288
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• 2017

Objective: Treating Class II subdivision malocclusion with asymmetry has been a challenge for orthodontists because of the complicated characteristics of asymmetry. This study aimed to explore the characteristics of dental and skeletal asymmetry in Class II subdivision malocclusion, and to assess the relationship between the condyle-glenoid fossa and first molar. Methods: Cone-beam computed tomographic images of 32 patients with Class II subdivision malocclusion were three-dimensionally reconstructed using the Mimics software. Forty-five anatomic landmarks on the reconstructed structures were selected and 27 linear and angular measurements were performed. Paired-samples t-tests were used to compare the average differences between the Class I and Class II sides; Pearson correlation coefficient (r) was used for analyzing the linear association. Results: The faciolingual crown angulation of the mandibular first molar (p < 0.05), sagittal position of the maxillary and mandibular first molars (p < 0.01), condylar head height (p < 0.01), condylar process height (p < 0.05), and angle of the posterior wall of the articular tubercle and coronal position of the glenoid fossa (p < 0.01) were significantly different between the two sides. The morphology and position of the condyle-glenoid fossa significantly correlated with the three-dimensional changes in the first molar. Conclusions: Asymmetry in the sagittal position of the maxillary and mandibular first molars between the two sides and significant lingual inclination of the mandibular first molar on the Class II side were the dental characteristics of Class II subdivision malocclusion. Condylar morphology and glenoid fossa position asymmetries were the major components of skeletal asymmetry and were well correlated with the three-dimensional position of the first molar.

• The korean journal of orthodontics
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• v.24 no.2
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• pp.275-294
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• 1994

The occlusal interference during adolescent period makes some effects on growth and development and morphological changes. And so, if we could predict the the timing and results of orthodontic treatment who have occlusal interference during adolescent period, it may be helpful for diagnosis and treatment planning of orthodontic treatment. For about those, the purpose of this study was to evaluate the effects of the posterolateral displacement by the metal casting crown with inclined pathway on the mandibular condyle and morphologic changes of mandible in the rat. The experimental animals were thirty six Sprague-Dawley male rats of 8 weeks old. Eight of them was used as control group, and experimental group 1 ( continuous appliance wearing group ) was composed of sixteen and experimental group 2 ( appliance removal group after worn the appliances during 3 months ) was composed of remaining twelve. The animals of experimental grouop 1 were sacrificed after 1, 2, 3, 6 months from beginning of the experiment and experimental group 2 were sacrificed 1, 2, 3 months after removal of the appliance from worn the appliance during 3 months. Both of mandible and temporomandibular joint were observed histologically and radiologically. The results were as follows : 1. In experimental group 1, the mandibular length and lower posterior height were decreased with experimental period, while the lower anterior height was increased, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were profound as compared with control group. 2. In experimental group 1, both of the thickness of the condylar cartilage were thinned in the posterosuperior region, and this phenomenon was more prominent on right than left in 3-Mo experimental period and both sides were marked thinned in 6-Mo experimental period. 3. In experimental group 2, the lower anterior height was low and lower posterior height was high as compared with experimental group 1, and the curvature of lower incisors and lingual inclination of anterior alveolar bone were recovered to control group. 4. In experimental group 2, both of the thickness of the condylar cartilage were thickened in the posterosuperior region, and this phenomenon was more prominent with experimental period. 5. In experimental group 2, the mandibular length was short, lower anterior height was hight, the curvature of lower incisors were profound, and in histologically, both of the thickness of the condylar cartilage were thickened in the posterosuperior region as compared with control group. As shown above, the occlusal interfemce affected the condylar cartilage, curvature of lower incisor, inclination of anterior alveolar bone, mandibular length, and anterior and posterior height. When the interference was removed, significant recover was found in condylar cartilage, mandibular length, and posterior height. Although no significance was found, other items of measurement showed trends for recovery.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.153-159
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• 2013

Purpose: Nowadays, checkbite methods and a digital sensor are used to analyze the movement of mandible. However, there are no study comparing two methods. Therefore, this study has compared measuring the condylar inclination methods by using the new ARCUSdigma 2 system and the checkbite method. Materials and methods: Young 20 adults without any orthodontic treatment experiences, missing teeth, and restorations with the change of occlusal plane were tested. Angles of condylar path were measured 3 times each, based on Camper's line, by using two methods. KaVo PROTAR Evo 7 semi-adjustable articulator was used and the data were statistically analyzed. Results: 1. The anterior sagittal condylar inclination by ARCUSdigma 2 system were measured as $26.97^{\circ}({\pm}7.38^{\circ})$ on the left side and $29.80^{\circ}({\pm}8.19^{\circ})$ on the right side. The lateral condylar inclination were measured as $5.75^{\circ}({\pm}3.47^{\circ})$ on the left side and $8.10^{\circ}({\pm}4.98^{\circ})$ on the right side. 2. The anterior sagittal condylar inclination by checkbite method were measured as $25.20^{\circ}({\pm}6.53^{\circ})$ on the left side and $28.18^{\circ}({\pm}7.38^{\circ})$ on the right side. The lateral condylar inclination were measured as $10.97^{\circ}({\pm}5.63^{\circ})$ on the left side and $12.03^{\circ}({\pm}5.22^{\circ})$ on the right side. There was no statistically significant difference between male and female (P>.05). 3. The lateral condylar inclinations of ARCUSdigma 2 were statistically significantly smaller than that of checkbite method (P<.05). Conclusion: In Both of 2 methods, there was no statistically significant difference between male and female (P>.05). However, the lateral condylar inclinations of ARCUSdigma 2 were statistically significantly smaller than that of checkbite method (P<.05).