• 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.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.34 no.4
• /
• pp.246-251
• /
• 2012

Purpose: The purpose of the study is to evaluate the effectiveness of anterior segmental osteotomy (ASO) in bimaxillary protrusion (BP) patients by comparison between the mandibular soft and hard tissue changes from orthodontic treatment and ASO. Methods: All 44 patients were diagnosed with BP in Kyung-Hee Medical Center. Orthodontic treatment with teeth extractions were underwent by 23 patients (Group A) and 21 patients underwent ASO (Group B). Mandibular soft and hard tissue changes were measured and evaluated, which were based on the vertical and horizontal reference line in lateral cephalometric radiographs. Statistical significance between the changes and correlation between each measurement were analyzed. Results: The amount of B point movement was lesser than that of the lower incisal tip (LIT) retraction, and LIT was tilted lingually in group A. The posterior movement discrepancy between LIT and B point was insignificant, and the inclination of lower incisor was not changed in group B. The soft tissues, including the lower lip, showed a posterior movement and reduction in the depth of mento-labial groove. According to the correlation analysis, the movement of the lower incisor was significantly related to the movement of the lower lip in group A, and the movement of the lower incisor was significantly related to that of the movement of lower lip, B point and Pog in group B. Conclusion: The orthodontic treatment in BP patients results in posterior tilting movement of the lower incisor, but ASO results in the bodily movement of the lower incisor. Consequently, ASO is more effective in BP cases because it ensures the controlled movement of the lower incisors.

• The korean journal of orthodontics
• /
• v.35 no.6 s.113
• /
• pp.451-458
• /
• 2005

Cephalometric superimposition is unable to evaluate tooth movement along the occlusal plane and the errors of photographing and superimposition of the occlusogram is also inevitable. The purpose of the present study was to evaluate the rotational movements of the maxillary posterior teeth following space closure after extraction of maxillary first premolars. using 3D dental images. In 19 adult females. analysis of rotational movements of the maxillary posterior teeth was performed between the initial and final 3D dental images superimposed on the maxillary hard palate. The results showed a diversity of rotational movements of posterior teeth. The causes of various rotational movements may be different rotation of molars in each case at the beginning of treatment. individual characters of the dental arch and tooth morphology. The results of the study indicate that accurate evaluation of rotational movements of posterior teeth following space closure after extraction of premolars using 3D dental images can be obtained through the subdivision of tooth movement during the initial aligning, space closure and finishing stages.

• The korean journal of orthodontics
• /
• v.23 no.4 s.43
• /
• pp.633-644
• /
• 1993

There has been so much controversies about the position of upper and lower jaws, and their first permanent molars in normal occlusion and Angle's class $I{\cdot}II{\cdot}III$ malocclusions. So, the purpose of this study is to compare the position of upper and lower jaws, and their first molars in normal occlusion and Angle's class $I{\cdot}II{\cdot}III$ malocclusions by lateral cephalometric analysis. The sample consisted of one hundred and twenty girls(thirty in each group) who had completed growth. The findings of this study were as follows : 1. In class I malocclusion, both maxilla and mandible were slightly posterior position than normal occlusion, but they showed harmonious relationship. 2. In class II malocclusion, the mandible was greatly retruded, and the maxilla was also slightly retruded to the cranial base as compared with normal occlusion. 3. In class III malocclusion, the maxilla was significantly retruded to the cranial base, but no significant difference was found in mandibular position as compared with normal occlusion. 4. The maxillary first molar was located at posterior position in class II malocclusion, and anterior position in class III malocclusion to the cranium, so that the rotation of mandible was influenced by that. 5. The mandibular first molar showed constant relationship to the mandible in all four groups, but different position to the cranial base in direct proportion to the mandibular position. 6. On the treatment planning of class III malocclusion, it seems to be better to promote the mandibular horizontal growth by inhibiting the vertical growth of maxillary molar area, and on the treatment planning of class III malocclusion, it seems to be better to promote the antero-inferior growth of maxilla mi to promote the mandibular vertical growth by inducing the vertical growth of maxillary molar area.

• The korean journal of orthodontics
• /
• v.25 no.4
• /
• pp.453-463
• /
• 1995

Most commonly used axis for central incisors in lateral cephalometric radiographs is the line connecting root apex and incisor edge. However, crown axis and root axis do not always coincide in cases of malocclusion patients. The angle created by these axis are called the collum angle, which should be considered in orthodontic diagnosis and treatment. In this study, 31 Class I malocclusion, 30 Class II division 1 malocclusion, 31 Class II division 2 malocclusion, and 31 Class m malocclusion patients were selected and their collum angles were measured. Correlation between these angles and malocclusions was investigated, and the correlation analysis with other parameters in cephalometrics was done. The results were as follows ; 1. The mean collum angles according to the types of malocclusions are ; $3.11^{\circ}{\pm}3.54^{\circ}$ for Class I, $1.23^{\circ}{\pm}2.41^{\circ}$ for Class II division 1, $3.77^{\circ}{\pm}4.39^{\circ}$ for Class II division 2, and $3.90^{\circ}{\pm}4.08^{\circ}$ for Class III malocclusion. 2. Statistically significant differences in collum angles were noted between Class II division 1 group and Class II division 2 and Class III group. 3. Significant correlations were found between collum angles and other parameters used in cephalometrics, namely IMPA for Class I, Wits for Class II division 1, Overbite for Class II division 2 and for ClassIII.

• The Journal of Korean Academy of Prosthodontics
• /
• v.58 no.1
• /
• pp.50-57
• /
• 2020

The loss of posterior support and the abnormal jaw relation can cause pathologic findings. If deep bite patients with multiple missing teeth, can not have the stable posterior contact, the mandible moves posteriorly, and consequently the overjet and overbite get worse. And when the mandibular irregular occlusal plane is corrected, it is easier to have the bilateral balanced occlusion with the maxilla. So the treatment goal is to give proper posetrior support and establish appropriate anterior guidance, and ultimately provide improved mastication and esthetics recovery. In this case, a 68 year old man, having deep bite without posterior support was evaluated by the vertical dimesion decision flow-chart. An available prosthetic height, anterior occlusal relation such as overjet, overbite and the esthetic part such as facial height and the cephalometric analysis are the factors to be considered.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.39 no.4
• /
• pp.357-365
• /
• 2012

There are orthodontic treatment which involves tooth movements and orthopedic treatment which involves skeletal movement. In childhood and adolescence, especially for the treatment of orthopedic treatment, the evaluation of bone maturity and growth potential is very important. The purpose of this study is to assess the developmental stage and to compare the amount of mandibular growth with cephalometric radiographs and hand-wrist radiograph in 6 to 13-year-old children with normal occlusion. The results are as follows : SMI and CVM showed a significant correlation (p < 0.05). Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of hand-wrist and Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn increased with increasing maturity of cervical vertebrae maturation. Also Ar-Go, Co-Go, N-Go, S-Gn, N-Me, Co-Gn, Go-Me, Go-Gn showed a significant correlation with each of the cervical vertebrae maturation stages and hand-wrist maturation stages (p < 0.05). These results suggested that mandibular growth had a significant correlation with cervical vertebrae maturation stages and hand-wrist maturation stages.

• The korean journal of orthodontics
• /
• v.26 no.5 s.58
• /
• pp.557-568
• /
• 1996

The purpose of this study was to analyze the growth changes of ODI and APDI with age on the three facial growth patterns. The biennial serial cephalometric radiographs of 19 male and 14 famale samples with normal occlusion during 10 years were used in this study. The samples were divided into three groups - drop type, neutral type, forward type - by the total change of the Y-axis during the periods of the study. The findings in this investigation indicated the following: 1. The mean values and standard deviations of each age group in each facial type of male and famale were obtained. 2. The difference of ODI and APDI among the 3 facial types was not significant through all observed ages(P)0.05). The size of ODI appeared large consistently in order of the drop, neutral, and forward type in both male and female through all observed ages. 3. The ODI and APDI were maintained without any charges with age during the periods of the study(p>0.05). 4. In correlation analysis between the total change of the Y-axis and 6 measurements, the AB plane angle and facial angle showed correlation in both male and female(p<0.05), the APDl in only female(p<0.001), but the ODI not appeared correlation in either male or female(p>0.05).

• The korean journal of orthodontics
• /
• v.30 no.6 s.83
• /
• pp.669-675
• /
• 2000

Excessive production of parathyroid hormone causes bony disorder such as periosteal bone resorption and bone pain due to excessive skeletal demineralization. A Class III facial deformity case with generalized root resorption presented bete was fumed out to be due to hyperparathyroidism. Clinical and cephalometric analysis revealed a straight skeletal profile with a retruded maxilla and a prognathic mandible. The x-ray findings demonstrated generalized root resorption of entire dentition to different degree. There also appeared osteoporosis like immature trabecular structure with the evidence of ground glass appearance. Serum test showed elevated 1evel of parathyroid hormone and growth hormone. Change of cranial growth by hyperparathyroidism can be dependent up(In a decreased bone apposition in viscerocranial growth site and abnormalities in cranial suture growth. It is possible to hypothesize that growth retardation of maxilla at least partially be accounted lot hyperparathyroidism. Therefore, regarding to the definite etiology of skeletal Class III and orthodontic treatment planning considering root resorption and osteoporosis, the early diagnosis for the hyperparathyroidism should be carefully carried by clinical and laboratory studies.

• The korean journal of orthodontics
• /
• v.34 no.6 s.107
• /
• pp.497-505
• /
• 2004

The purpose of this study was to evaluate the post-retention stability of the lower incisor axis in Class II division 2 malocclusions. The dental casts and lateral cephalograms from before (T1) and after (T2) orthodontic treatment and long-term post-retention (T3) in 62 Class II division 2 malocclusion cases were included in this study. After several linear and angular measurements at each time were taken, the significance in the amount of change of the lower incisor axis for each gender and extraction versus non-extraction was evaluated. The results showed that the lower incisors that inclined labially during treatment were unstable and relapsed to the original lingual position in Class II division 2 malocclusions (p<0.001). There was no significant difference between extraction and non-extraction groups for the amount of lingual relapse of the lower incisors (p>0.05). There was no significant difference between male and female groups for the axial change of the lower incisors (p>0.05). As a result of multiple regression analysis, the cephalometric measurement best predicting the lower incisor position to the A-Pog line post-retention was pre-treatment L1-Apog(mm) and pre-treatment SNGoMe$(^{\circ})$. Because of the instability of labially inclined lower incisors after orthodontic treatment, the treatment goal should be the pre-treatment incisor axial position.