• The korean journal of orthodontics
• /
• v.17 no.2
• /
• pp.299-310
• /
• 1987

The purpose of this study was to examine soft tissue and hardtissue changes following orthognathic surgery in patients with mandibular prognathism lateral cephalometric films were obtained immediate before surgery, 48 hours following surgery, and 6 months following surgery. 18 patients were selected (10 men, and 6 women) for this study, who had received orthognathic surgery. Statistical analysis for the each time interval differences were performed with the SPSS package The results were as follows, *In the cases of mandibular sagittal split osteotomy 1 LI point was moved backward (average 7.55mm) 48 hours following surgery. 6 months later, it was returned forward (average 1.1mm) Relapse rate was 14.6% 2 Pog was moved backward (average 8.3mm) 48 hours following surgery The ratio of horizontal change of soft tissue to hard tissue at pog is 0.95 1 *In the cases of maxillary Le-Fort I osteotomy & mandibular sagittal split osteotomy. 3. A point was moved forward (average 3.31mm) 48 hours following surgery. 6 months later, it was returned backward (average 0.31) Relapse rate was 9 4% 4 6 months later, the ratio of facial convexity angle change of soft tissue to hard tissue is 0.63 1.

• The korean journal of orthodontics
• /
• v.17 no.2
• /
• pp.199-213
• /
• 1987

Upon analyzing the literature, it becomes apparent that norms for orthodontic diagnosis were from normal occlusion with pleasing face, and that the form and size of craniofacial skeleton were different between racial or ethnic groups. Therefore, this study was intended to establish Korean adult norms be useful for diagnosing the cases and to compare those to other ethnic or racial groups. Lateral cephalometric radiographs were taken of ninety-one Korean adults with normal occlusion showing pleasing face consisted in forty-three males and forty-eight females. The subjects ranged in age from seventeen to twenty-six years. The tracings involved measurements that were analyzed with a digitizer. The findings of this study can be summarized as follows, 1. Norms of Korean adult males, females, and combined sexes were established. 2 It was found that in the form and shape of craniofacial skeleton, there were no significant differences between males and females, but in the size males were larger than females 3. There were a great variation between ethnic or racial groups in the measurements of craniofacial skeleton 4 The size of Korean cranial base was smaller than the American Caucasian. 5 The maxilla and mandible of Korean were less protruded than those of the other ethnic groups 6 The dental pattern of Korean were more proclined than that of the American Caucasian and less protruded than that of the American Negro and the North Indian.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.15 no.2
• /
• pp.123-128
• /
• 1993

For the purpose of studying postsurgical stability of mandibular prognathism, 18 patients(8 men and 10 women) were selected who underwent sagittal split ramus osteotomy and lateral cephalograms taken preoperatively, immediate postoperatively, and over 6-month follow-up were traced and analysed. The following results were obtained. 1. Average magnitude of setback vas 11.0mm, and aberage relapse was 3.0mm, so the rate of relapse was 27%. 2. Magnitude of mandibular setback contributed to relapse. 3. The patients of less than 10mm setback showed average 10% of relapse rate, and it was of little clinical significance. 4. Proper detachment of pterygomasseteric sling prevention of clockwise rotation of proximal segment and rigid fixation are recommended for the better postoperative stability.

• The korean journal of orthodontics
• /
• v.20 no.1
• /
• pp.197-207
• /
• 1990

This comparative study was undertaken to investigate the position of the hyoid bone in unilateral cleft lip and palate individuals. The materials for this study consisted of 35 subjects with surgically repaired unilateral cleft lip and palate (25 males, 10 females) and 40 subjects with normal facial morphology (20 males, 20 females). Cephalometric measurements of unilateral cleft and palate individuals were compared with those of non-cleft individuals. The conclusions of this study were obtained as follows: 1. To the anterior cranial base, the hyoid bone in unilateral cleft lip and palate individuals was located downward as compared with non-cleft individuals. 2. To the mandible, the hyoid bone in unilateral cleft lip and palate individuals was located backward as compared with non-cleft individuals. 3. The distance between the dorsum of the tongue and the inferior border of the hard palate in unilateral cleft lip and palate individuals was longer than that in non-cleft individuals. 4. Unilateral cleft lip and palate individuals showed no significant difference in the distance between the hyoid bone and the dorum of the tongue as compared with non-cleft individuals.

• The korean journal of orthodontics
• /
• v.24 no.3 s.46
• /
• pp.521-534
• /
• 1994

The purpose of this study was to compare the differences in measurements between cephalometric radiographs and digigraphs of Dolphin Imaging System. 26 Korean adult male and 24 adult female with normal occlusion were selected. For each subject lateral cephalogram was taken. Digitizing with Digigraph Work Station of Dolphin in System. was performed as well. 50 tracings and 50 digigraphs were analyzed with Yonsei, Ricketts, Burstone analyses. The comparable measurements between tracing group and digigraph group were statistically analyzed. The results were as follows: 1. 13 of 64 comparable measurements did not show any statistically significant difference (P>0.05) between tracing group and digigraph group. 2. Three of the measurements with FH plane as a reference plane did not show any statistically insignificant difference. All measurement with SN plane as a reference plane showed statistically significant difference(p<0.05). 3. The measurements which showhed no statistically significant difference were mostly short distance linear measurements while most of the angular measurements showed statistically significant difference(p<0.05).

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.27 no.3
• /
• pp.267-275
• /
• 2005

Obstructive sleep apnea syndrome (OSAS) is characterized by sleep-induced obstruction of the upper airway that results in cessation of airflow. Obstruction can occur at a number of points in the airway, but frequently in the oropharynx. A diagnostic evaluation includes cephalometry, computed tomography, magnetic resonance imaging, acoustic reflection technique, polysomnography and fibroptic endoscopy. Cephalometric measurements of the patients with obstructive sleep apnea have revealed that posterior airway anatomy has strong relations with the symptoms of them. A lateral cephalogram is routinely obtained in the radiologic evaluation of sleep apnea patients. The purpose of this study is to provide a the lateral cephalometric korean norms for the diagnosis and treatment of the patients with obstructive sleep apnea by analyzing the abnormal occlusion of Korean adults.

• The korean journal of orthodontics
• /
• v.19 no.1 s.27
• /
• pp.77-93
• /
• 1989

The purpose of the present study were to disclose whether the depth of the mandibular antegonial notch can be used as an indicator of mandibular growth potential. The patients composed of 76 samples and were classified following 3 groups, based on the depth of mandibular antegonial notch : Deep notch group (more than 3mm), Neutral notch group (1-3mm), Shallow notch group (less than 1mm). For each case, the first lateral cephalograms were taken prior to the start of treatment and the second films 3-4 years after. The results were as follows; 1. Deep notch group had a shorter corpus, less ramus height and greater genial angle than did Shallow notch group. 2. Deep notch group had a more retrusive mandibular position than Shallow notch group. 3. Deep notch group had longer total anterior facial height and longer anterior lower facial height group. 4. Deep notch group grow vertical clockwise growth pattern, while Shallow notch group grow horizontal counterclockwise growth pattern. 5. Deep notch group had less mandibular growth than Shallow notch group during observation period.

• The korean journal of orthodontics
• /
• v.19 no.1 s.27
• /
• pp.219-243
• /
• 1989

The purpose of this study was to evaluate the effects of the chincap therapy on the craniofacial structure in persons with skeletal Class III malocclusion. The patients selected for this study were treated with extra-oral chincap therapy only. Both control and treatment samples were obtained from Seoul National University Hospital where these longitudinal data were gathered. 55 treated patients and 14 control patients were studied. The mean ages at the 1st evaluation was 8 years 3 months in the treatment sample and 9 years 4 months in the control sample. The duration of chincap therapy was variable but averaged 2 years of treatment. Post-treatment observation procedeeded for 1 year 2 months. Active treatment and post treatment effects were evaluated. The results were as follows: 1. Neither significant restraint nor acceleration of growth was found in the cranial base and maxilla during treatment. 2. A distal rotation of the mandibular complex was seen. 3. Some amount of restraint of growth was found in mandibular body length, ramus height, mandibular length during treatment. 4. The genial angle was reduced. 5. After removal of the chin-cap, forward displacement of the mandible took place.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.27 no.2
• /
• pp.157-161
• /
• 2001

The purpose of this study cephalometrically evaluated changes in the posterior airway space for patients with obstructive sleep apnea syndrome(OSAS) before and after surgical advancement of the maxilla and mandible. The change in calculated airway resistance was correlated with the respiratory disturbance index(RDI). Twenty cephalometric radiographs were traced before and after surgery to determine the posterior airway area and calculate resistance. Polysomnograms of each patient were obtained before and after surgery. All patients had a decrease in calculated airflow resistance in the airway. The mean amount of resistance was 865.15 before surgery, decreasing to 192.65 after surgery (p<0.01). Eighty-five percent of the patients experienced improvement in their RDI. Reduction in the RDI appears to be due to an increase in the posterior airway space and decrease in flow resistance.

• The korean journal of orthodontics
• /
• v.17 no.1
• /
• pp.23-32
• /
• 1987

There are variations in regional cranial and facial balance as a normal developmental process and regional imbalances often tend to compensate each other to provide functional equilibrium. This study was designed to analyse the patterns of morphologic harmony and inharmony inherent in normal occlusion and malocclusion. The subjects consisted of 92 individuals with normal occlusion and 60 Class III malocclusion patients. Their lateral cephalograms were traced and analysed using the counterpart analysis described by Enlow. The normal occlusion group was divided into Normal Types A and B according to the relative positions of Points A and B. The following conclusions were reached: 1 The normal occlusion consisted of $28.3\%$ of Normal Type A and $69.6\%$ of Normal Type B. 2. The Normal Type A and B differed from each other in the morphology of the cranial base, the mandibular ramus and corpus, and the functional occlusal plane. The Normal Type B showed considerable mandibular protrusion effect in the effective dimension and alignment of the above factors. 3. Most normal individuals showed some degree of disharmony among morphologic factors but the deviations were relatively small. 4. The Normal Type B was less balanced than the Normal Type A. 5. More regional imbalances were involved in Class III malocclusion and the imbalances were more severe.