• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.486-490
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• 1994

Maxillary first molar is the key in normal occlusion. Mesial drifting of maxillary first molar result form early loss of second deciduous molar. Mesial drifted maxillary first molar was treated by headgear, Hawley appliance with screw, brasswire, etc. But, these appliance should be necessary for patients cooperation. Recently, several appliance for molar distalizing without patients cooperation has been introduced. We are reporting in this paper about distalizing of mesial drifted maxillary first molar because of early loss of deciduous second molar by open coil jig. Distalization of molar by open coil jig is predictable, rapid, painless method without mecesscity of patient cooperation.

• The korean journal of orthodontics
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• v.45 no.4
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• pp.171-179
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• 2015

Objective: To compare dentoalveolar and skeletal changes produced by the pendulum appliance (PA) and the distal screw appliance (DS) in Class II patients. Methods: Forty-three patients (19 men, 24 women) with Class II malocclusion were retrospectively selected for the study. Twenty-four patients (mean age, $12.2{\pm}1.5years$) were treated with the PA, and 19 patients (mean age, $11.3{\pm}1.9years$) were treated with the DS. The mean distalization time was 7 months for the PA group and 9 months for the DS group. Lateral cephalograms were obtained at T1, before treatment, and at T2, the end of distalization. A Mann-Whitney U test was used for statistical comparisons of the two groups between T1 and T2. Results: PA and DS were equally effective in distalizing maxillary molars (4.7 mm and 4.2 mm, respectively) between T1 and T2; however, the maxillary first molars showed less distal tipping in the DS group than in the PA group ($3.2^{\circ}$ vs. $9.0^{\circ}$, respectively). Moreover, significant premolar anchorage loss (2.7 mm) and incisor proclination ($5.0^{\circ}$) were noted in the PA group, whereas premolar distal movement (1.9 mm) and no significant changes at the incisor ($0.1^{\circ}$) were observed in the DS group. No significant sagittal or vertical skeletal changes were detected between the two groups during the distalization phase. Conclusions: PA and DS seem to be equally effective in distalizing maxillary molars; however, greater distal molar tipping and premolar anchorage loss can be expected using PA.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.543-548
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• 1997

The first permanent molar takes important place in the occlusion. Malposition of the lower first molar is frequently due to mesial migration, which is occurred by early exfoliation of the second deciduous molar or proximal caries of deciduous teeth. Above things happen without any consideration of space maintainer, prompt measures for space regaining have to be started. Especially in the case with early loss of the second deciduous molar, it has been said that there is no suitable appliance for maintaining the space before the eruption of the permanent first molar. In distalizing the upper first molar, headgears have been routinely used, which its result was definitely depended on cooperation of the patients. Nowadays, appliances such as pendulum appliances, K-loop, magnets, which can be used without cooperation of the patients, are introduced. Jones Jig, one of the molar distalizing appliances, was used on the patients who visited department of pediatric dentistry in Seoul National University Dental Hospital complaining of no eruption space for the lower second bicuspid. Either removable splint or lingal arch was used as the anchorage. Jones Jig was favorably used in the lower molar, where vestibule is shallow, and this is a case report on the satisfactory result thereof.

• The korean journal of orthodontics
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• v.46 no.2
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• pp.96-103
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• 2016

Objective: To compare the transverse dental changes induced by the palatally applied Frog appliance and buccally applied Karad's integrated distalizing system (KIDS). Methods: We evaluated the pre- and post distalization orthodontic models of 39 patients, including 19 treated using the Frog appliance, which is palatally positioned (Frog group), and 20 treated using KIDS, which is buccally positioned (KIDS group). Changes in intermolar and interpremolar distances and the amount of maxillary premolar and molar rotation were evaluated on model photocopies. Wilcoxon and Mann-Whitney U tests were used for statistical evaluations. A p-value of < 0.05 was considered statistically significant. Results: Significant distopalatal rotation of premolars and distobuccal rotation of molars were observed in Frog group (p < 0.05), while significant distopalatal rotation of molars (p < 0.05), with no significant changes in premolars, was observed in KIDS group. The amount of second premolar and first molar rotation was significantly different between the two groups (p < 0.05 and p < 0.001, respectively). Furthermore, expansion in the region of the first molars and second premolars was significantly greater in KIDS group than in Frog group (p < 0.001 for both). Conclusions: Our results suggest that the type and amount of first molar rotation and expansion vary with the design of the distalization appliance used.

• The korean journal of orthodontics
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• v.45 no.1
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• pp.20-28
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• 2015

Objective: The purpose of this study was to observe stress distribution and displacement patterns of the entire maxillary arch with regard to distalizing force vectors applied from interdental miniscrews. Methods: A standard three-dimensional finite element model was constructed to simulate the maxillary teeth, periodontal ligament, and alveolar process. The displacement of each tooth was calculated on x, y, and z axes, and the von Mises stress distribution was visualized using color-coded scales. Results: A single distalizing force at the archwire level induced lingual inclination of the anterior segment, and slight intrusive distal tipping of the posterior segment. In contrast, force at the high level of the retraction hook resulted in lingual root movement of the anterior segment, and extrusive distal translation of the posterior segment. As the force application point was located posteriorly along the archwire, the likelihood of extrusive lingual inclination of the anterior segment increased, and the vertical component of the force led to intrusion and buccal tipping of the posterior segment. Rotation of the occlusal plane was dependent on the relationship between the line of force and the possible center of resistance of the entire arch. Conclusions: Displacement of the entire arch may be dictated by a direct relationship between the center of resistance of the whole arch and the line of action generated between the miniscrews and force application points at the archwire, which makes the total arch movement highly predictable.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.464-474
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• 2009

To distalize the maxillary molars, the traditional techniques such as extra-oral traction, Wilson distalizing arches, removable spring appliances and Schwarz plate-type appliances have been used. But, these need considerable patient cooperation. For minimal patient compliance, many practitioners use the pendulum appliances. Several clinical studies demonstrated pendulum is effective molar distalization appliance in the growing patient(using the premolars and the palate as anchorage). But unfortunately, maxillary anterior teeth also shift mesially as the molar moves distally. As a result anchorage loss is occurred. To overcome these disadvantages, we used bone-supported pendulum, combined the conventional pendulum with Skeletal Anchorage System(SAS). The miniscrew was implanted in the anterior paramedian region of the median palatal suture, which has comparatively sufficient bone thickness and is low risk to damage on the dental follicles. We report three cases, using bone-supported pendulum for the maxillary molar distalization in children. After treatment, we find out anchorage stability, minimal unfavorable anterior tooth movement and sufficient molar distalization.

• The korean journal of orthodontics
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• v.43 no.2
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• pp.101-109
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• 2013

Objective: To evaluate the efficiency of the Frog appliance (FA) alone or in combination with headgear for distalizing the maxillary molars. Methods: Fifty patients (25 males and 25 females) aged 12.6 - 16.7 years who received treatment for Class II malocclusion at the Orthodontic Clinic of Al-Baath University were selected for this study and randomly divided into 2 equal groups. Maxillary molar distalization was achieved using the FA alone (group 1) or a combination of the FA with high-pull headgear worn at night (group 2). Lateral cephalograms were obtained before and after treatment. Results: The maxillary molars moved distally by 5.51 and 5.93 mm in groups 1 and 2, respectively. Distal movements were associated with axial tipping by $4.96^{\circ}$ and $1.25^{\circ}$, and with loss of anchorage by mesial movement of the second maxillary premolars by 2.70 and 0.90 mm in groups 1 and 2, respectively. The combined use of the FA and nighttime high-pull headgear decreased the distalization time and improved the ratio of maxillary molar distalization movement relative to the overall opening space between the first maxillary molars and second premolars. Conclusions: The FA can effectively distalize the maxillary molars, this distalization associates with some unfavorable changes. Nighttime use of high-pull headgear combined with the FA can reduce these unfavorable changes and improve treatment outcomes.

• The korean journal of orthodontics
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• v.46 no.1
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• pp.55-61
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• 2016

Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.4
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• pp.771-775
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• 1997

Ectopic eruption is defined as abnormal eruption and results in malpositioned teeth and abnormal root resorption of adjacent teeth. Ectopic eruption, first reported by Chapman, occurs in 3% of the population and that mostly in the maxilla. Etiologic factors include narrow maxilla, large maxillary teeth, retarded calcification of the first molar, inclined eruption path of the first molar and retruded position of the maxilla. Impaction of the second molar is rare and occurs mostly in the mandible. Major causes are large teeth and insufficient arch length. Halterman has devised a method of distalizing a ectopically erupting first molar by cementing a band on the second deciduous molar with a hook soldered and a button bonded to the occlusal surface of the first permanent molar. Ectopically erupted posterior teeth should be treated early to maintain normal development of the dentition, harmony of facial growth and occlusal support, a failure to do so could result in severe malocclusion, periodontal damage and continued root resorption of the adjacent teeth. Early detection and treatment is thus vital. The author is submitting this report as he has obtained favorable results in treating a patient who came to the SNUDH Dept. of Pediatric Dentistry complaining of the first molar by using a modified Halterman appliance.

• The korean journal of orthodontics
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• v.34 no.3 s.104
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• pp.269-277
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• 2004

A modified removable appliance for molar distalization called C-activator was used in a 10-year old male patient with a Class II anterior deep bite malocclusion with upper arch discrepancy. The treatment plan involved correcting the Class ll relationship, distalizing both upper first molars, and regaining space for the erupting canines. The C-activator, which was used for 6 months, consisted of a labial framework formed from .036-in stainless steel wire and an acrylic monobloc. Both the closed helices of the labial framework were compressed for reactivation during the C-activator treatment period. C-activator mechanics simultaneously achieved distalization of the upper first molars into their proper positions and repositioning of the mandible. After 21 months of treatment, the correct oberbite and overjet was obtained and contributed to an Improvement in facial balance. The treatment results were stable 6 months after debonding. Fabrication and placement of the new appliance and clinical procedures are detailed, and the treatment sequence and results of this case are presented as follows.