• Journal of the korean academy of Pediatric Dentistry
• /
• v.34 no.4
• /
• pp.599-612
• /
• 2007

The present study was designed to compare the morphological and structural differences of craniofacial structures among 146 children with Class I and Class III malocclusions. The results below were obtained from the study. 1. Sphenoethmoidal synchondrosis continues to grow later in Class III. 2. Anteroposterior length of the nasomaxillary complex was significantly shorter in Class III, but the height of the nasomaxillary complex was similar. 3. Mandibular length and mandibular body length were longer in Class III, but had no statistical significance. Lower anterior facial height was shorter in Class III, but had no statistical significance. 4. Dentoalveolar height was similar between Class I and Class III. 5. In Class I, anterior cranial base took part in the anteroposterior length of the nasomaxillary complex and the mandible. 6. In Class III, anterior cranial base and middle cranial base had higher correlation with the mandible with aging. These results suggest that there exist a little differences between Class I and Class III malocclusions at age $7{\sim}11$, but growth patterns are mostly similar. Therefore it is necessary to correct Class III malocclusions at an early age before skeletal differences appear.

• The korean journal of orthodontics
• /
• v.27 no.3 s.62
• /
• pp.431-444
• /
• 1997

This research was carried out to compares the treatment effects of Horizontal and Vertical type activators in Angle's Class II div. 1 maloccusion patients with mandibular retrusion dand to find out whether different treatment effects or growth pattern were observed between sexes in each study groups. The results were as follows: 1. In Horizontal activator group, forward positioning of mandible and vertical increase in anteror face as examplified by increase of LAFH and AEM were observed when pre and post-treatment datas were evaluated. 2. Males samples in Horizontal activator group showed increase in mandiular length accmpanied by posterior positioning of maxilla, wheras female samples in Horizontal activator group showed increase in mandibular body length, labial inclination of mandibular incisors and increase in lower anterior facial height .3. In vertical activator group, increase in AFH, LAFH, PFH and LPFH were observed when pre and post treatment datas were evaluated. 4. Male samples in Vertical activator group showed increase in mandibular body length and anterior and posterior facial heights, whereas females samples of Vertical activator group showed mainly increase in anterior facial height. 5. When pre and post treatment datas of Horizontal and Vertical activator groups were compared, skeletal difference were mainly observed in pretreatment datas but dental difference were observed in post treatment datas ,indicating that two actiators differ only in their effects to dental variables. 6. Difference between sexes were noted after treatment although no difference were observed between sexs in each groups before treatmentt. This indicates that inherent growth effects in each sex exerts more influence 1km appliances used for treatment.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.28 no.3
• /
• pp.369-373
• /
• 2001

The congenital missing of mandibular second premolars is among the common dental anomaly in children. When a second premolar is diagnosed as congenitally missed, we should consider many factors influencing the treatment plan such as patient's age, states of roots of 2nd primary molar, degree of crowding, skeletal growth pattern, facial profile, procumbency of the incisor and lower facial height, etc. The mineralization of the second premolars begins in the majority of cases at the age of $2\sim2\frac{1}{2}$ years, but this period varies more widely than those for other permanent teeth. Also, mandibular second premolars show the greatest variations in differentiation and calcification. For this reason, aplasia of this group of teeth cannot be diagnosed at early age and with the same degree of certainty. From the clinical studies with 2 cases and some literature review on late development of second premolars, it could be summarized as follows : 1. The 2 cases showed marked delay in the development of mandibular second premolars. 2. After the crypt formation, the speed of calcification seemed nearly normal, suggesting that the delay was due to differentiation rather than calcification. 3. When one is encountered with similar conditions, it would be desirable to consider the possibility of delayed tooth development.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.34 no.1
• /
• pp.17-25
• /
• 2012

Purpose: Recently, a three dimensional approach to hard and soft tissues of the maxillofacial area has been widely used. This study was to evaluate the reproducibility and accuracy of a stereocamera compared to actual measurement methods using a digital caliper and digitizer. Methods: The stereoscopies of 7 head dummies with different sizes and shapes were obtained using a Di3D system (Dimensional Imaging, Glasgow, UK) after marking reference points on facial areas. From the obtained stereoscopy, 10 measurements representing the width, height and depth of each of the facial sections of the dummy were measured twice using a three dimensional reverse engineering software program (RapidForm$^{TM}$ 2006, Inus, Seoul, Korea). The x, y, and z coordinates of each of the three dimensional measurements were obtained and distances between two points were calculated. All procedures were repeated twice. The actual measurement method was performed twice, directly on dummies, using a digital caliper and values were compared with the previously determined values. Results: The results were as follows. In the ANOVA analysis, there were no significant statistical differences among the three measurement methods. In the Bonferroni analysis, with adjustments applied for multiple comparisons, there was no difference between actual measurement methods using a digitizer and a digital caliper. However, there was some difference between using a stereocamera and actual measurement methods using a digitizer and a digital caliper in values of $Ex_{Rt}-Ex_{Lt}$, $En_{Rt}-En_{Lt}$, $Ala_{Rt}-Ala_{Lt}$, $Ch_{Rt}-Ch_{Lt}$, G-Pg', $Ala_{Rt}$-Prn, $Ala_{Rt}$-Prn. The mean value for technical error in measurement (TEM) in Di3D (0.98 mm) was slightly higher than for a digital caliper (0.17 mm) and a digitizer (0.30 mm). In an intraclass correlation coefficient (ICC) there were no significant differences among the three measurement methods, but the Di3D system with the stereocamera showed relatively lower reproducibility compared to actual measurement methods using a digitizer and a digital caliper. Conclusion: These results indicate that some complementary measures may be needed to improve accuracy and reproducibility in the Di3D system with stereocamera.

• Journal of Oral Medicine and Pain
• /
• v.31 no.4
• /
• pp.337-346
• /
• 2006

Aims: The present study investigated the relationship between condylar resorption and craniofacial skeleton types(especially vertical relationships), the differences of craniofacial skeleton types between with open bite group and without open bite group, and the associations of anterior disc dislocation with or without reduction to condylar resorption with MRI. Patients selection and methods: Clinical examination, magnetic resonance imaging (MRI), panorama, lateral transcranial and lateral cephalometric radiographs in 34 patients with condylar resorption were used to investigate this relationship. Results and Conclusions: Patients with the following specific facial morphologic characteristics appear to be most susceptible to condylar resorption: (1) females were predominant, (2) patients' age ranged from 12 to 50 years old with a strong predominance for 2nd and 3rd decades, (3) patients had high mandibular plane angle and high gonial angle, (4) patients had decreased vertical height of the ramus, (5) patients had generally significant antegonial notch, (6) patients had predominance of Class I occlusal relationship with or without open bite but mandible was retruded as mean ANB 5.54 degrees, (7) condylar resorption rarely occurs in lower mandibular plane angle facial types, (8) although no statistically significant difference was found, the open bite group had a tendency more hyperdivergent skeletal pattern than the non open bite group, and (9) imaging demonstrates from small resorbing condyles to idiopathic condylar resorption and TMJ articular disc dislocations. Thus, morphologic features of patients with vertical discrepancies may represent a risk factor for the development of condylar resorption.

• Journal of Yeungnam Medical Science
• /
• v.18 no.1
• /
• pp.112-122
• /
• 2001

Background: Cleft lip and palate deformity have unknown patterns of maxillofacial growth and development. The maxillofacial growth can be affected either by congenital or environmental factors such as infection and trauma. Surgical repair of cleft lip and palate may interfere the subsequent growth and development of maxillofacial region. The purpose of this study is to evaluate the characteristics of maxillofacial growth patterns in adult cleft lip and palate patients. Materials and Methods: The material for this study consisted of 17 adult male patients with cleft lip and palate. Cephalometric tracing and measurements were done by one investigator. The relationship between 17 cleft lip and palate patients and Korean norms were evaluated statistically. Results: There were statistically differences in Na. perpendicular to point A, SNA angle, effective maxillary length, maxillofacial differencial. Wit's appraisal and upper incisor to point A(p < 0.01). Pogonion to Na. perpendicular also statistically differed(p < 0.05). Other measurements didn't statistically differ. Conclusion: It was evident that in adult cleft lip and palate patients, maxilla was retruded and short. Careful cleft lip and palate repair and treatment are recommended for facilitating normal growth of maxilla.

• The korean journal of orthodontics
• /
• v.19 no.2
• /
• pp.130-143
• /
• 1989

The purpose of this study was to assess the early effect of FR III on the growing patients with anterior cross-bite. The lateral cephalograms and models were obtained from 7 patients at the time of pretreatment and correction of anterior cross-bite. The results were as follows: 1. A slight tendency of rotation toward anterosuperior direction and the growth to anterior direction were shown in maxilla. 2. There were a little change of mandibular vertical position and increase in lower facial height although some variations existed. 3. The bodily or labial tipping movement was shown in maxillary incisors. 4. The lingual tipping of mandibular incisors was shown in all cases. 5. Maxillary arch width increased while mandibular arch width usually changed a little although some variations existed. But it was difficult to summary in a word because variable responses were noted according to a wide variety of skeletal type, growth, and malocclusion.

• The korean journal of orthodontics
• /
• v.29 no.1 s.72
• /
• pp.37-49
• /
• 1999

Forty-four females with normal temporomandibular joint were compared with fifty-one females with abnormal temporomandibular joint. An orthodontic study model and lateral cephalometric radiographic were used to investigate the relationship between TMD group and non-TMD group in long face patterns. The result were followed that ; 1. There were no significant in overbite and overjet amount. 2. A mandibular 1'st molar inclination and height to the mandibualr plane were more mesial inclined in TMD groups. 3. The functional factors, which were craniocervical posture , tongue posture and hyoid bone position, were no significant.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.35 no.3
• /
• pp.523-531
• /
• 2008

Maxillary molar distalization is a treatment approach for patients with Class II malocclusions who do not require extractions and mesial movements of mandibular molars. The pendulum appliance is effective for distalization of the maxillary molars and independent of patient cooperation. This appliance can stabilize the maxillary premolars and use the palatal rugae area as an additional anchorage. However, caution is needed to control collateral effects, including increase of lower facial height, incisor protrusion and damage to the rugae area. This article reports the cases in which maxillary molar distalization achieved by pendulum appliance resolves the space problems and corrects the molar relationships.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.21 no.2
• /
• pp.149-165
• /
• 1999

The pathomechanism of obstructive sleep apnea(OSA) is not clearly elucidated. The possible mechanisms are pathologic reduction of pharyngeal muscular tonus during sleep, abnormal anatomical stenosis of nasopharyx or a combination of the above two mechanisms. It is very important to find the cause(anatomical location or pathologic dynamic change) of OSA in order to treat it. Cephalometric analysis in patients with obstructive sleep apnea is a good method for evaluating anatomical morphologic change but it cannot give any information about the dynamic changes occurring during sleep. On the contrary, nasopharyngeal endoscopy offer 3 dimensional image and information about the dynamic changes. Accordingly, these two diagnostic tools can be utilize in the diagnosis and treatment planning of OSA Cephalometric analysis of craniofacial skeletal and soft tissue morphology in 53 patients with OSA and 43 controls was performed and cephalometric analysis and nasopharygeal endoscopy were performed in 9 patients with OSA in order to come up with individualized therapy plans. Following results were obtained ; Patients with OSA showed 1. body weight gain 2. clockwise mandibular rotation 3. increased anterior lower facial height 4. inferiorly positioned hyoid bone 5. increased length of soft palate 6. decreased sagittal dimension of nasopharyx 7. increased vertical length of inferior collapsable nasopharyx 8. increased length of tongue Through cephalometric analysis and nasopharygeal endoscopy(mutually cooperative in diagnosis), 9. one can find the possible origin of OSA and make a adequate individualized therapy plan and predict accurate prognosis. Cephalometric analysis and nasopharygeal endoscopy are highly recommended as a diagnostic aid in OSA patients