• Journal of the korean academy of Pediatric Dentistry
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• v.7 no.1
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• pp.17-20
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• 1980

The purpose of this investigation was to make a comprehensive study and evaluation of the oral hygiene status by considering dental plaque index in 60 children age 7-9. The obtained results were as follows 1) Average plaque index of total mandibular teeth was higher than that of maxillary teeth. (Mandible; 2.14, Maxilla; 1.98) 2) In average plaque index per tooth surface, plaque index of facial surface was higher than that of lingual surface in maxilla and lower in mandible. 3) In mixed dentition, dental plaque occur most frequently and in greater quantity on the buccal surfaces of the maxillary permanent 1st molars and the lingual surfaces of the mandibular anterior permanent incisors.

• The korean journal of orthodontics
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• v.50 no.3
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• pp.216-226
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• 2020

Root resorption can be caused by several factors, including contact with the cortical bone. Here we report a case involving a 21-year-old female with Angle Class II, division 1 malocclusion who exhibited significant root resorption in the maxillary right central incisor after orthodontic treatment. The patient presented with significant left-sided deviation of the maxillary incisors due to lingual dislocation of the left lateral incisor and a Class II molar relationship. Cephalometric analysis demonstrated a Class I skeletal relationship (A point-nasion-B point, 2.5°) and proclined maxillary anterior teeth (upper incisor to sella-nasion plane angle, 113.4°). The primary treatment objectives were the achievement of stable occlusion with midline agreement between the maxillary and mandibular dentitions and appropriate maxillary anterior tooth axes and molar relationship. A panoramic radiograph obtained after active treatment showed significant root resorption in the maxillary right central incisor; therefore, we performed cone-beam computed tomography, which confirmed root resorption along the cortical bone around the incisive canal. The findings from this case, where different degrees of root resorption were observed despite comparable degrees of orthodontic movement in the bilateral maxillary central incisors, suggest that the incisive canal could be an inducing factor for root resorption. However, further investigation is necessary to confirm this assumption.

• The Journal of the Korean dental association
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• v.23 no.7 s.194
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• pp.625-630
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• 1985

11 years 7 months old female had a reverse object of anterior teeth and class III molar relationship. Maxillary right and left canines were erupted labially and lower left lateral incisor was congenitally missed. She was treated by rapid palatal expansion and full band technique with extraction of maxillary and mandibular second molars. The following results were obtained. 1. Maxilary arch was expanded. 2. Anterior cross-bite and crowding was corrected. 3. Molar relationship was corrected. 4. Profile was somewhat improved.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.174-182
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• 2024

In patients with multiple missing molars, wear patterns or displacement of anterior teeth, collapsed occlusal plane, and reduction in vertical dimension may occur. Particularly, in case of a few remaining teeth on one side, a removable partial denture has biomechanical disadvantage. For this reason, an implant-assisted removable partial denture with a few implant surveyed crowns can be an alternative. In this case, due to the right mandibular posterior teeth loss, the anterior teeth were severely worn and the occlusal plane was collapsed. With minimal increasing vertical dimension, oral rehabilitation was performed using a maxillary fixed prosthesis and mandibular implant-assisted removable partial denture. As a result, functional and aesthetic clinical outcomes were obtained.

• The korean journal of orthodontics
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• v.44 no.5
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• pp.236-245
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• 2014

Objective: To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction. Methods: Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with preadjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed. Results: Both groups showed full retraction of the maxillary anterior teeth by controlled tipping and space closure without altered posterior occlusion. However, the preformed C-wire group had a shorter retraction period (by 3.2 months). Furthermore, the maxillary molars in this group showed no significant mesialization, mesial tipping, or extrusion; some mesialization and mesial tipping occurred in the conventional C-wire group. Conclusions: Preformed C-wires combined with maxillary TSADs enable simultaneous leveling and space closure from the beginning of the treatment without maxillary posterior bonding. This allows for faster treatment of dentoalveolar protrusion without unwanted side effects, when compared with conventional C-wire, evidencing its clinical expediency.

• The korean journal of orthodontics
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• v.45 no.1
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• pp.38-46
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• 2015

Objective: This prospective clinical study aims to determine the differences between two treatment modalities for anterior open bite in growing patients. The treatment modalities involved the use of magnetic bite-blocks (MBBs) or rapid molar intruders (RMIs) applied with posterior bite-blocks. Methods: Fifteen consecutive patients with a mean age of 11.2 (standard deviation [SD] = 1.6) years and a mean open bite of -3.9 mm were treated with MBBs. Another 15 consecutive patients with a mean age of 10.9 (SD = 1.8) years and a mean open bite of -3.8 mm were treated with RMIs applied on bite-blocks. Cephalometric radiographs were obtained before (T1) and immediately after appliance removal (T2). The treatments lasted four months, during which the appliances were cemented to the teeth. The morphological changes were measured in each group and compared using logistic regression analysis. Results: The MBB group exhibited significantly greater decreases in SNA angle, ANB angle, overjet, and maxillary incisor angle (p < 0.05). The MBBs induced greater effects on the maxilla and maxillary dentition. The MBBs restrained maxillary forward growth and retracted the maxillary incisors more effectively than did the RMIs. Consequently, changes in the intermaxillary relationships and overjets were more distinct in the MBB group. Conclusions: The anteroposterior differences between the appliances suggest that MBBs should be preferred for the treatment of patients with Class II open bites and maxillary incisor protrusions.

• The Journal of the Korean dental association
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• v.10 no.5
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• pp.273-276
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• 1972

The original sample in this investigation included 36 children around the age of eight (mean age:8 year-lmonth) at the beginning. Study casts were obtained and measured every 6 months in two years of longitudinal study period in order to observe the changes of maxillary dental arch as well as the eruptional status of the maxillary lateral incisors. The results were as follows.: 1) The length of upper dental arch was increased gradually during the examination period. 2) The width between maxillary first molars was increased gradually during the examination period. 3) Intercanine distance in upper dental arch was increased gradually and the increment was conspicuous immediately after the eruption of maxillary lateral incisors.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.4
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• pp.313-326
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• 2007

With rising prevalency of mouth breathing children caused by developing civilization and increasing pollution, there are many maxillary transverse discrepancy patients with undergrowth of maxilla. For improving this, maxillary mid-palatal suture splitting was often performed. The purpose of this study was to analyse the stress distribution on the craniofacial suture and cranium after rapid maxillary expansion by finite element model. The boy(13Y6M) was chosen for taking computed-tomography for finite element model. Three-dimensional model of maxilla, first premolar, first molar, buccal and lingual part of rapid maxillary expansion were constructed. 1. The alveolar bone adjacent to the first molar and the first premolar that was affected directly by rapid maxillary expansion was displaced laterally approximately 4.04mm at maximum. The force decreased toward anterior region and frontal alveolar bone displaced laterally about 3.18mm. 2. A forward maximum displacement was exhibited at zygomatic process middle region. 3. At maximum, maxillary median part experienced 0.973mm downward repositioning and 0.65mm upward repositioning at lateral alveolar bone. 4. Von mises stress was observed the largest stress distribution around teeth and zygomatic buttress. 5. The largest tensile force was observed around alveolar bone of teeth, while compression force was observed at zygomatic buttress.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.297-306
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• 1991

The purpose of this study is to improve the availabilities of radiographic technics as diagnostic methods to evaluate maxillary sinus in dental clinic. For the morphologic study of maxillary sinus, 20 dry maxillas were used and intraoral standard views, orthopantomograms, and skull P-A views were taken. For measuring the vertical image magnification rates, 5 sites in maxillary molar regions of 5 dry mandibles were selected radndomly and 25 wires of the determined sizes for selected portions were attached to the sites, after then, intraoral radiograms with bisecting technic and orthopantomograms were taken. The acquired results were as follows: 1. The anterior extension of the maxillary sinus on orthopantomogram was the distal side of the canine in 45.45% of subjects, the mesial side of the canine in 27.27%, the lateral incisor in 9.09%, the mesial side of the 1st premolar in 9.09%, and the mesial side of the 2nd pre-molar in 9.09%. 2. The positional relationship between the floor of maxillary sinus and the apex of alveolar socket revealed superimposed type in 58.3% of subjects, approached type in 33.3%, and separated type in 8.4%. 3. The morphology of inferior border of maxillary sinus was simple V or U shape in edentulous stage and V or wide U shape in alveolar socket stage. 4. The vertical image length on intraoral film taken by bisecting technic was magnified by 27.23% on the average and the length on orthopantomogram by 12.35%. 5. The inferior borders of maxillary sinus coinciding with each of the areas bearing the anterior and the posterior teeth on skull P-A view were determined.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.119-128
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• 2011

In the process of assessing the children with anterior crossbite in early mixed dentition, it has frequently been detected that the stronger the skeletal pattern of the malocclusion is, the more markedly delayed the development and eruption of maxillary teeth are. If the anteroposterior characteristics of craniofacial skeleton has any relationship with dental maturation, the evaluation of dental development and eruption was thought to be able to contribute to early diagnosis of crossbite in children. This study was performed for the purpose of elucidating the relationship between dental maturation of maxillary teeth and some cephalometric values in children with anterior crossbite of maxillary undergrowth type in early mixed dentition. Among the children in Hellman dental age IIA and IIC who attended the Pediatric Dental Clinic of Pusan National University Hospital with orthodontic problems, cases with Class III malocclusion were classified and 50 cases of maxillary undergrowth type and type with normal maxilla respectively were randomly selected and studied as subjects. From their lateral cephalographs and panoramic radiographs, their anteroposterior skeletal features, the dental maturity and eruption rate were obtained of each group and data were analyzed to yield the results as follows: 1. Comparing the maturity of maxillary teeth of both groups, only the first molars of maxillary undergrowth group showed significantly slower development and eruption (p<0.05). 2. There was high correlation between maturation of maxillary 1st molar and chronological age(p<0.05). 3. Among the parameters of anteroposterior relationship of skeletal pattern in maxilla and mandible. Wits was revealed as a useful index to predict both the calcification and eruption rate of the 1st molars whereas SNA was to eruption rate(p<0.05).