The retraction of anterior teeth could be performed more easier by inducing of skeletal anchorage system rather than by conventional method on orthodontic treatment. But, we wonder how effective the system draws well without anchorage loss and draws anterior teeth aside posteriorly, and if the system can reduce the time, in comparison with the anchorage of posterior teeth. For that reason we have studied on the subject of patients, who were required the maximum anchorage on orthodontic treatment and the cases without crowding. The subjects of the experimental group are 35 areas of 20 people who were inserted miniscrews after Mx or Mn 1st premolar extracted. Also, the subjects of the control group are 81 areas of 45 people who were not inserted miniscrews. Compared the anchorage loss of experimental group with control one, we could get the result that the anchorage loss of experimental group is 1.034+/-0.891mm and control group is 2.790+/-1.882mm(P<0.01). Compared the space closing time of experimental group with control one, we could get the result that the space closing time of experimental group is 369.40+/-110.81days and control group is 406.56+/-231.63days. But the result of comparing space closing time has no significance in statistics. We recognized that the experimental group is more faster than the control group in the canine retraction velocity from the result ; the speed of a experimental group has as much as 0.60+/-0.23mm/30days while the speed of a control group has 0.44+/-0.35mm/30days(P<0.05). So, we could convince that orthodontic miniscrew is used effectively in the cases required the maximum anchorage.
Bicuspid ; Crowding ; Humans ; 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

It is important to understand the operating mechanism and force system of fixed appliance that most effective for individual tooth movement in various orthodontic appliances. The arch wire system of fixed appliance is devided into 3 types, which is continuous arch, segmented arch and sectional arch. The last two types have longer interbracket distance and simple force operating points, so it is easy to control force system by operator. But the continuous arch has shorter interbracket distance and various bracket geometry, so it is hard to control and anaylze the force system. The purpose of this study was three dimentional force and moment analysis of continuous arch system by finite element method, which is similar situation to three dimentional elastic beam in structural engineering. Several sample form of various bracket geometry and artificial lower crowding typodont made by author were constructed, analyzed and compared each other. The results were as follows: 1. The force magnitude is linear proportional to the degree of displacement or tilting of the bracket. 2. The force magnitude is inversely non-linear proportional to the interbracket distance. 3. In three dimensional typodont model, while the force can be compared with that of the sample form in the area where adjacent bracket geometry is simple, the force is much more than the expected value in the area where adjacent bracket geometry is complex.
Crowding ; Orthodontic Appliances ; Tooth Movement

This article describes the orthodontic treatment of a 31-year-old Korean female patient with gummy smile and crowding. The patient showed excessive gingival display in both the anterior and posterior areas and a large difference in gingival heights between the anterior and posterior teeth in the maxilla. To correct the gummy smile, we elected to intrude the entire maxillary dentition instead of focusing only on the maxillary anterior teeth. Alignment and leveling were performed, and a midpalatal absolute anchorage system as well as a modified lingual arch was designed to achieve posterosuperior movement of the entire upper dentition. The active treatment period was 18 months. The gummy smile and crowding were corrected, and the results were stable at 21 months post-treatment.
Crowding ; Dentition ; Female ; Humans ; Maxilla ; Tooth

When treating borderline cases which have mild crowding, non-extraction treatment may be considered firstly. But crowding may be reappeared by relapse and it may have problems in esthetics and stability. Secondarily four first premolar extraction treatment may be considered. But this may cause dish-in face by overretracting anterior teeth. In this cases, extraction of four second premolar is preferred because this resolves crowding without aggravating profile and has good stability after treatment. So we review cases treated by four second premolar extraction which show good treatment results and stability. The patients had good profile, Class I molar relationship, mild crowding and skeletal discrepancy and their growth had almost completed.
Bicuspid* ; Crowding ; Esthetics ; Humans ; Molar ; Recurrence ; Tooth

OBJECTIVE: The purpose of this study was to evaluate the effects of malocclusion and orthodontic treatment on the self-esteem of adolescents. METHODS: The subjects were composed of 3509 female middle school students. Each subject was evaluated with Rosenberg's Self-esteem Scale to measure the level of self-esteem and also evaluated the degree of crowding and soft tissue profile. RESULTS: Results showed that protrusion of lip area had no effects on self-esteem but crowding of upper anterior teeth had significant effects. The fixed orthodontic treatment group and the removable orthodontic treatment group reported no significant difference in self-esteem from the no orthodontic treatment experience group, but the debonding group showed significantly higher Self-esteem index. CONCLUSION: The results of this study suggest that anterior teeth alignment has influence on the self-esteem of female adolescents.
Adolescent* ; Crowding ; Female ; Humans ; Lip ; Malocclusion* ; Tooth

Nonextraction camouflage treatment in mild Class III malocclusion is achieved by backward movement of the lower dentition and forward movement of the upper dentition. Many camouflage treatment modalities have been used for distal tipping and distal movement of mandibular posterior teeth. The amount of distal movement of mandibular dentition can be improved in cases of severe crowding, even without the patient's cooperation, by using miniscrews for anchorage. However, miniscrew insertion may be unsuccessful, and it may contact the adjacent root because of the distal movement of dentition. Distal tipping of mandibular dentition can be achieved using multiloop edgewise archwires and intermaxillary elastics. However, the complexity of this wire design causes discomfort to patients. Recently, a new treatment using improved superelastic NiTi wires (ISWs) and intermaxillary elastics has been introduced. ISWs can deliver orthodontic force more effectively, and their use with molar tip-back treatment has several advantages-this approach is effective, simple, and easy to use and reduces patient discomfort. The aim of this study was to report a case of camouflage treatment using ISW with tip-back and intermaxillary elastics for distal tipping of mandibular posterior dentition and to evaluate the effectiveness of this treatment in a clinical setting.
Crowding ; Dentition ; Humans ; Malocclusion ; Molar ; Tooth

The purposes of this study were to clarify the effect of tooth size and arch size upon the crowding. 175 upper casts were measured and following conclusions were made. 1. Tooth size, intermolar width, 2nd premolar width of crowded group were not significantly different from those of noncrowded groups. 2. Intercanine width, arch length of noncrowded group were significantly larger than crowded group. 3. Multiple regression equations were derived by using tooth size, arch perimeter, arch length, intermolar width.
Bicuspid ; Crowding* ; Dental Arch* ; Statistics as Topic* ; Tooth*

The purpose of this study was to evaluate the availability of computer system for the measurement of tooth size in the model analysis through the comparison of two measurements: One was to use a computer; and the other was to use vernier calipers. Twenty sets of casts were used, which showed a moderate degree of crowding and full eruption of all teeth. The mesio-distal width of 12 teeth from the left central incisor to the left first molar at each set of the casts were measured twice with vernier calipers and a computer respectively. This measurement was repeated two weeks later. First, for the reproducibility analysis, the two computer measurements were compared then the vernier calipers measurements were compared. Second, all the teeth were sepapated into the region of mesiodistal contact points and its width was measured by a micrometer to obtain standard measurements. For the accuracy analysis, these standard measurements were compared with the measurements from the dental casts using two methods. The difference between them was defined as the measurement error. To investigate the cause of measurement error, an examination was made for the presence and degree of contact point deviation on each tooth from the upper and lower occlusograms, and the mesio-distal angulation of each tooth was measured with TARG. Following results were obtained through statistical analysis. 1. In the analysis for reproducibility ; the measurements with vernier calipers showed significant differences in three out of twelve teeth while the computer measurements showed significant differences in one out of twelve teeth. 2. In the analysis for accuracy : compared with the standard measurements, the measurements with vernier calipers showed significant differences in three out of twelve teeth while the compute measurements showed significant differences in two out of twelve teeth. 3. Compared with the standard measurements. the measurements with vernier calipers were apt to be larger at the upper first molar, and smaller at the lower first molar. The computer measurements, however, were apt to be larger at both upper and lower first molars. 4. the measurements with vernier calipers showed the largest error at the lowe first molar and the degree of error was variable according to the tooth while the difference of error was small in the computer measurements. 5. In the analysis for the correlation of the degree of measurement errors with the contact point deviation index and the mesio-distal crown angulation of each tooth, the measurements with vernier calipers did not show significant correlation while th measurements with computer showed slight positive correlations. The results of this study indicate that a computer system may be useful for the measurement of tooth size in the model analysis.
Computer Systems ; Crowding ; Crowns ; Incisor ; Molar ; Tooth*

OBJECTIVE: The purpose of this study was to evaluate the effects of malocclusion on the self-esteem of female university students. METHODS: The subjects were composed of 67 female university students who showed Class I molar relation, no missing or supernumerary teeth and has had no orthodontic treatment experience. Each subject was evaluated with Rosenberg's Self-esteem Scale to measure the level of self-esteem and also evaluated the degree of anterior crowding and lip protrusion through model analysis and cephalometric soft tissue profile analysis. RESULTS: The results showed that a protrusive profile and crowding of upper anterior teeth had significant reducing effects on the level of self-esteem. The protrusion and crowding groups showed no significant differences in self-esteem between groups. CONCLUSIONS: Malocclusion had significant negative effects on the self-esteem of female university students. Further research to investigate the negative psychological influence of malocclusion and the education of lay people about this influence is necessary.
Crowding ; Female ; Humans ; Lip ; Malocclusion ; Molar ; Tooth ; Tooth, Supernumerary