Collective changes caused by orthodontic tooth movement evaluated in a specific treatment modality could give suggestive information on the specific treatment strategy. The aim of this study was to investigate retrospectively the characteristics of the orthodontic tooth movement during surgical-orthodontic treatment in order to provide an effective presurgical orthodontic treatment planning for the maxillary premolar extraction modality in the skeletal Class III malocclusion patient. Pre- and posttreatment dental casts of skeletal Class III malocclusion patients with nonextraction (N=24) and the maxillary premolar extraction (N=31) were collected. The angulation and inclination measuring gauge (Invisitech Co. Seoul, Korea) was used to evaluate the orthodontic tooth movement. The changes in the maxillary and mandibular dental arch widths were also measured from the canines to the second molars. As a result, more palatal inclination change in the maxillary dentition was found with the premolar extraction modality than with the nonextraction modality. Linear regression analysis showed that the inter-arch width coordination was mainly due to the inclination changes of maxillary posterior teeth. We conclude that the indications and proper treatment planning for surgical-orthodontic treatment in skeletal Class III malocclusion with maxillary premolar extraction could depend partly on the magnitude of the transverse inter-arch coordination especially in the maxillary dentition.
Bicuspid* ; Dental Arch ; Dentition ; Humans ; Linear Models ; Malocclusion ; Molar ; Retrospective Studies ; Seoul ; Tooth ; Tooth Movement

Surgical-orthodontic treatment is an increasingly more common dental procedure whose unique psycho-social or psychological feature has not been fairly quantified objectively. Since the treatment of a surgical-orthodontic (or orthodontic) patient is part science and part art, a subjective recognition of a patient about his or her own treatment may be more important than technical success during and after treatment. Therefore, the knowledge of the patient's underlying psychological status could be useful in the prediction of patient's response to surgical-orthodontic (or orthodontic) treatment. The purpose of this study was to investigate and evaluate the psychological difference between conventional orthodontic patient and surgical-orthodontic patient by using locus of control (LOC) examination. Locus of control scale has been proven to be extremely useful in the prediction of a variety of human behaviors. Two types of locus of control data (I-score, Internal locus of control score; E-score, External locus of control score) were obtained for 42 surgical-orthodontic patients and randomly selected 42 conventional orthodontic patients (as a control group) matched for age and gender. No statistically significant difference was observed in the scale of internal and external locus of control between the groups of surgical-orthodontic patients and conventional orthodontic patients. However, in the group of surgical-orthodontic patients, males showed lower E-score (external locus of control score, higher internal locus of control tendency) than females. The results of this study suggested that the psychological background of surgical-orthodontic patients, in contrast with that of cosmetic surgery patients, has a similar disposition with that of orthodontic patients.
Female ; Humans ; Internal-External Control* ; Male ; Surgery, Plastic

The purpose of this study was to investigate the stress distribution and tooth displacement at the initial phase produced by 5 types of molar uprighting springs using finite element method. The three dimensional finite element model of lower dentition, bone and springs was composed of 5803 elements and 2071 nodes. The results were as follows: 1. In case of helical spring and root spring, intrusion of lower canine and first premolar were observed and distal tipping, translation and extrusion of lower second molar were observed. 2. In case of T-loop, modified T-loop and box loop, intrusion and distal translation of lower second premolar were observed, and the largest crown distal tipping and translation of lower second molar were observed in T-loop and the smallest were observed in box loop. 3. In case of T-loop with cinch-back, crown distal tipping and translation of lower second molar were decreased, but extrusion was also decreased. 4. With increase of activation in T-loop, mesial translation and crown distal tipping of lower second molar were increased and edentulous space was closing, but distal translation of second premolar was also increased. 5. With increase of tip-back bend in T--loop, distal tipping and translation of lower second molar were increased, but extrusion was also increased more largely.
Bicuspid ; Crowns ; Dentition ; Finite Element Analysis* ; Molar* ; Tooth

During diagnostic process of the orthodontic patients, it is not unusual to find canine impaction. Generally, the chief complaint of the patients is crowding or antetior crossbite which is not related with canine impaction, but sometimes they complainted delayed eruption of the canine or deviation of the adjacent teeth caused by canine impaction. Orthodondists have to make the proper treatment plan according to final treatment goals. On the following cases, two patients were diagnosed as a malocclusion with canine impaction, and were treated by different accesses, one by extraction, and the other by non-extraction each.
Crowding ; Humans ; Malocclusion ; Tooth

The purpose of this study was to evaluate the indications of bionator in Class II division 1 malocclusion. The 48 subjects were classified into good result group(groupl) and poor result group(group2) in reference to posttreatment molar relation, posttreatment overbite and overjet, posttreatment profile, and relapse. Pretreatment lateral cephalograms were calculated and evaluated by t-test and stepwise discrminant analysis. The results were as follows; 1. In jaw bone relationship, ANB, facial convexity angle, AB to facial plane angle were significantly different between two treatment groups. In denture pattern, Ll to facial plane, Ll to A-Pog, FMIA, and Ul to facial plane were significantly different and in soft tissue profile, protuberance of lower lip and upper lip were significantly different between two treatment groups. 2. The results in according to discriminant analysis stated that Ll to facial plane, ANB, FMIA and protuberance of lower lip help prediction of treatment result of bionator. 3. 3 major influential variables were obtained by stepwise discriminant analysis - Ll to facial plane, articular angle and ANB difference. And Fisher discriminant function was made by these three major variables.
Activator Appliances* ; Dentures ; Jaw ; Lip ; Malocclusion* ; Molar ; Overbite ; Recurrence

The porpuse of this in vito study was to evaluate the effects of different acid etching times on the enamel srface morphology, shear bond strength and debinding failure mode of orthodontic attachment. Ninety six extracted human mandibular premolars were divided into eight groups of twelve teeth. The buccal surfaces were etched with 37% phosphoric acid 5, 10, 15, 30, 45, 60, 90 and 120 seconds, respectively. Two teeth from each group were used for scanning electron mocroscope examination. On the etched buccal aurfaces of remaining teeth, orthodontic attachments(lingual buttons) were bonded with light cured orthodontic adhesive. Twenty four hours after bonding, a Instron universal testing machine was used to determine shear bond strength of orhtodontic attachment to enamel. After debonding, bases of orthodontic attachments and enamel surfaces were examined under stereoscopic microscope to determine failure mode. Statistical analysis of the data was carried out with one way ANOVA and Duncan';s multiple range test. The results were as follows : 1. There was no statistically significant difference in shear bond strengths between the various etching times(p<0.05). 2. The failure modes of orthodontic attachments had some differences. In 5, 10 and 15 seconds etching groups, the percentage of adhesive/ enamel interface failure was higher than that of adhesive/attachment interface failure. On the contrary, 30, 45, 60, 90 and 120 seconds etching groups, the recults were reersed. 3. The etching parerns of enmel surfaces had a great variation. So, we could not find any correlation between etching pattern and bond strength. 4. The findings in this study indicate that in vito reduction of the etching time to 5 seconds maintains clinically acceptable bond strength. However, further study is required to determine the cause of failure mode in 5, 10 and 15 seconds groups.
Bicuspid ; Dental Cements ; Dental Enamel* ; Humans ; Tooth

The purpose of this study was to evaluate changes in mandibular movement patterns after orthognathic surgery in skeletal Class III patients. The sample consisted of 20 Class III malocclusion patients(9 males, 11 females). Just before and after(2-7months) surgery, maximum opening & closing movement, mandibi3 ar border movement on sagittal, frontal and horizontal planes were recorded using Sirognathograph & BioPak EGN. On each record, 21 items were measured and statistically analyzed. The results were as follows 1. Angle of protrusive movement on sagittal plane showed greatest change after surgery. Also, as the incisal guidance was established by surgery, straight path of protrusive movement became curved line. 2. Maximum opening distance and maximum antero-posterior distance on maximum opening & closing movement, maximum opening distance on sagittal plane, angle of left lateral excursion on frontal plane were statistically significant after snrgery(p<0.01). 3. Maximum width of lateral excursion on frontal plane, distane of right lateral excursion and angle of maximum left lateral excursion on horizontal plane were statistiraily significant after surgery(p<0.05). 4. Maximum opening distance and maximum antero-posterior distance on maximum opening & closing movement showed significant differences according to post-surgical time(p<0.05). More recovery of range of movement occured in 5-7month group than in 2-3month group. 5. As the occlusal interferences were removed by orthognathic surgery, irregular opening & closing path became smooth curve.
Humans ; Male ; Malocclusion ; Orthognathic Surgery*

The purpose of this study was to evaluate treatment effects of bionator in Class II division 1 malocclusion by FEM(Finite Element Method). The 73 subjects were classified into good result group and poor result group in reference to posttreatment molar relation, posttreatment overbite and overjet, posttreatment profile, and relapse. Pretreatment and posttreatment lateral cephalograms were taken and FEM was performed. The results were as follow; 1. There was no statistical significance in treatment changes between the sexes, and between the treatment result groups. 2. Treatment changes were not significantly different among the age groups. 3. The effect of treatment period groups on skeletal and dentoalveolar changes were analyzed using ANOVA. Body of maxilla, upper incisor, anterior face, ramus, upper anterior face, lower anterior face and treatment effect were correlated with the treatment period, but correlation coefficients were low. 4. The results of present investigation confirm that Class II bionator can assist in the correction of Class II division 1 malocclusion, mainly due to dentoalveolar changes. 5. There is significant difference in skeletal and dentoalveolar pattern between good result group and poor result group. In poor result group, maxilla was relatively downward and backward rotated, mandible was relatively backward rotated, upper incisor was in relatively lingual position, lower incisor was in relatively labial position.
Activator Appliances* ; Humans ; Incisor ; Malocclusion* ; Mandible ; Maxilla ; Molar ; Overbite ; Recurrence

The chin is one of the factors which express human character, and appropriately protruding chin is very important to harmonious profile. the purpose of genioplasty is to reshape the chin and improve the facial esthetics which is one of the purposes of orthodontic treatment. It can be classified as augmentation genioplasty which enlarge the chin vertico-horizontally and reduction genioplasty which smallen it. The examples to apply this procedure are as follows. 1. advancement of retruded chin 2. reduction of chin prominence 3. control of chin vertical dimension 4. correction of asymmetry
Chin* ; Congenital Abnormalities* ; Esthetics ; Genioplasty* ; Humans ; Malocclusion* ; Vertical Dimension

The purpose of this study was to evaluate the diagnostic value of SONOPAK* in internal derangement of TMJ by comparing the spectral analysis data of TMJ sounds recorded by SONOPAK with the results of MRI. From the patients who came to Department of Orthodontics, Seoul National University Dental Hospital for treatment of malocclusion, eighteen adult patients (five males and thirteen females) with TMD symptoms were selected. After joint sounds were checked by a pediatric stethoscope, they were recorded and analyzed by the SONOPAK. The spectral analysis of the SONOPAK provided SONOPAK INTERPRETATION data about the stage of internal derangement, which were compared with the results of MRI. Among the patients whose disc positions were diagnosed as 'normal' by MRI, there were no false positive diagnosis by the SONOPAK INTERPRETATION. But in the cases of anterior disc displacements(reducible and/or nonreducible), most of SONOPAK INTERPRETATION data did not coincide with MRI results. In conclusion, it is not adequate to try to differentiate reducible and non-reducible anterior disc displacements on the basis of joint sounds. And it is recommended not to determine the stage of internal derangement according to the nature of sounds. We suggest that the diagnostic value of the SONOPAK will be enhanced when clinicians combine some other informations such as clinical signs/symptoms and other supplementary diagnostic tools), and that more data be incoporated into the SONOPAK INTERPRETATION software.
Adult ; Diagnosis ; Humans ; Joints ; Magnetic Resonance Imaging ; Male ; Malocclusion ; Orthodontics ; Seoul ; Stethoscopes ; Temporomandibular Joint*