• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.491-495
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• 1994

The ectopic eruption is defined rise to be abnormal eruption, which gives to displacement of the teeth and abnormal root resorption of adjacent teeth. The ectopic eruption of first permanent molar is approximately 2-4% of the population, most of them are in the maxilla, rarely in the mandible. In the case of the second permanent molars, most of them are found in the mandible for the reason of the arch length discrepancies and large size of the teeth. The ectopic erupted molars should be treated early in order to coordinate normal growth pattern and to obtain good occlusal support. So, this should be early diagnosed and treated. But, ectopically erupting molars are often self-corrected, hence periodic follow-up is required. The methods of the treatment are largely classified into surgical, surgical-orthodontic, and orthodontic method. Especially in orthodontic method, they are divided as follows; appliances that is positioned at the contact point for unlocking and the distal movement, fixed and removable appliance that is connected to more than one tooth, and occlusion guiding method after disking or extraction of the second deciduous molar. The report presents the good results in treating patients, whose chief complaint was ectopic eruption of mandibular permanent molars.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.4
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• pp.519-525
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• 2010

Ectopic eruption means the eruption of the tooth in an abnormal position due to multiple factors, which found most frequently in maxillary fist permanent molars, mandibular lateral incisors and maxillary permanent canines. Ectopic eruption of the maxillary first permanent molar occurs when the molar erupts with a more mesial angulation than normal, and locks itself in an atypical resorption on the distobuccal root of the second primary molar. The maxillary first permanent molar plays important roles for mastication and occlusion, so ectopically erupted maxillary first permanent molars should be relocated into proper position. Treatment options are separation by insertion of the brass wire or elastic rings, preparation of distal aspect of the maxillary second primary molar, using fixed or removable appliance with finger spring, and placement of space maintainer or space regainer after extraction of the maxillary second primary molar. We report three cases treated of ectopically erupted maxillary first permanent molar by re-setting of stainless steel crowns, placement of brass wire and using active plate. We could find out distal movement of maxillary first permanent molars into proper position and normal occlusion.

• Journal of Veterinary Clinics
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• v.35 no.4
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• pp.137-140
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• 2018

A five-month-old toy poodle was referred for treatment of bilateral mandibular fractures. Preoperative skull and dental radiographs showed rostral mandibular fractures and permanent teeth that had not yet erupted. In addition to providing stability for the healing of fractures, it is very important to focus on restoring normal occlusion. The mandibular fractures were repaired using interdental wiring in a dentate area where the deciduous canines and fourth premolars were stable and could be used to anchor the interdental fixation. In the absence of an erupted permanent mandibular first molar, the modified Risdon wiring was performed using the deciduous mandibular fourth premolars as anchor teeth. An intraoral splint was placed on the mandibular teeth using self-curing composite resin. Five months after surgery, the patient had experienced no complications, and the permanent teeth had erupted normally. In this case, which involves a small-breed puppy with deciduous dentition, treatment with a wire-reinforced interdental splint using intact deciduous fourth premolar teeth as anchor teeth can be considered as a suitable method for rostral mandibular fracture restoration.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.1
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• pp.51-59
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• 2016

The purpose of the present retrospective study was to analyze gender, age, awareness, etiology, and treatment choice in patients with failed eruption of the mandibular first molar. Radiographic material and dental records from 67 patients with 74 mandibular first molars with failed eruption treated during the years 2001-2014 were evaluated. As results, the prevalence of mandibular first molar with failed eruption was higher in males than females, and the average awareness age was 9.19 years old. The most common etiological cause was unknown, and the next most common causes were abnormal eruption pathway and odontogenic tumor in order. In this study, it is suggested that more dental education to children about the time of eruption of permanent tooth is required, and the importance of regular dental check-ups is emphasized during mixed dentition.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.2
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• pp.335-340
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• 2007

Primary teeth and the permanent successor must be understood as interdependent units, where each one of them interacts with and depends upon the other. The spread of pulpal inflammation in primary teeth to the periradicular tissues can lead to early eruption, enamel hypoplasia or hypocalcification, developmental arrest of permanent successor. Also the periapical inflammation cause permanent tooth displacement in various direction. We describe here two clinical cases of displaced permanent successor caused by periapical lesion of mandibular primary molar in children.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.337-343
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• 2020

Molar-incisor malformation (MIM) is a new type of root anomaly reported recently. The characteristics of MIM are dysplastic root formations, constriction of pulp chambers and presence of calcified matrices at the level of cementoenamel junction in permanent first molars and primary second molars. In some cases, permanent maxillary incisors are also affected. The permanent first molars of the patient in this case report were affected with MIM. Generalized pulp stones were observed in overall primary dentition. Micro-computed tomography (micro-CT) imaging and scanning electron microscope-energy dispersive X-ray spectrometer analysis were performed on the extracted mandibular first molar and maxillary primary second molar of the patient. Micro-CT images revealed the discontinuity of enamel directly connected to an accessory canal of the root.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.136-142
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• 2010

Ectopic eruption is defined as the eruption of the tooth in an abnormal position or orientation. In the molar region, ectopic eruption may cause distal root resorption and premature exfoliation of the neighbor teeth and uncontrolled space loss is followed. Prolonged partial impaction of the permanent molar may also cause undetected caries or abscess formation of the neighbor teeth. While 66% of ectopically erupting permanent molars are corrected spontaneously without treatment, the treatment is necessary for the irreversible ectopic eruption cases. The optimal treatment approach depends on a number of factors including the clinical eruption status of the molar, amount of enamel ledge and the mobility of the neighbor tooth, and the presence of pain or infection. This case report presents the results of treatment of the ectopically erupting maxillary first permanent molars and mandibular second molars using elastic separators or modified Halterman appliance with or without surgical approach.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.43-52
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• 2000

Hemifacial microsomia ( HFM ) is the second most common craniofacial abnormalies. HFM represnted a spectrum of clinical findings such as hypoplasia of the mandibular ramus and condyle, confinement of maxilla growth, external and/or middle ear defects, involvement of some cranial suture, buccal soft tissue, facial nerve, and muscles in the affected side. HFM often showed progressive facial asymmetry and occlusal plane slanting to the affected side with growth. There were several reports about asymmetry of tooth maturation, hypodontia, delayed eruption, enamel hypoplasia in HFM. Since teeth develope in close association with size and morphology of the maxillary and the mandible, it is highly likely that dental changes will be present in HFM. So the Purpose of this study was to investigate the differences of the primary and the permanent teeth dimensions in the maxillary and the mandibular dentition between the affected and the non-affected side of HFM.. The sample of this study consisted of 34 unilateral HFM Patients (18 males and 16 females, average age : 5 year 11 months old). The authors examined the mesiodistal and the faciolingual dimensions of the primary and the permanent teeth and performed statistical study by using paired t-test. The results were as follows 1. The mesiodistal dimensions of the mandibular second primary molar and the mandibular first permanent molar in the affected side of HFM were significantly smaller than those of non-affected side. But there were no significant differences in the anterior teeth and the mandibular first primary molar. It means that a gradient of severity from anterior teeth to posterior teeth was found in the mandibular dentition. 2. Although there were no significant differences in the faciolingual dimensions of the primary and the permanent teeth in the maxillary and the mandibular dentition between the affected and non-affected side of HFM, there were general trend of compensatory increase in faciolingual dimension of the mandibular primary and the permanent teeth in the affected side Therefore these results showed that HFM might affect on the abnormality of tooth dimension, especially the most posterior teeth, in the affected side of the mandible.

• The korean journal of orthodontics
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• v.21 no.2 s.34
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• pp.341-351
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• 1991

Dental maturity is one of the index of physiological maturity indicators. To investigate the relationship between dental maturity and chronological age, the author took the orthopantomograms of 984 students, aged 7 through 17 years, having normal occlusion. The orthopantomograms were examined and calcification degree of each tooth on the left side was rated according to the method described by Demirjian. On the basis of findings of this study, the following results were obtained. 1. The root completion periods of mandibular permanent teeth were as follows; Central Incisor M $8.32{\pm}1.03\;years$ F $7.96{\pm}1.04\;years$ Lateral Incisor M $9.40{\pm}1.30\;years$ F $9.01{\pm}0.90\;years$ Canine M $12.81{\pm}1.24\;years$ F $11.42{\pm}0.94\;years$ 1st Premolar M $12.76{\pm}1.74\;years$ F $12.19{\pm}1.33\;years$ 2nd Premolar M $13.31{\pm}1.88\;years$ F $12.88{\pm}1.49\;years$ 1st Molar M $9.60{\pm}1.69\;years$ F $9.30{\pm}1.16\;years$ 2nd Molar M $14.38{\pm}1.73\;years$ F $13.96{\pm}1.63\;years$ 2. Sexual differences in same age group at given calcification stage were not significant statistically. 3. The developmental order in mandibular permanent teeth was as follows; a) central incisor, b) lateral incisor, c) 1st molar, d) canine and 1st premolar, e) 2nd premolar, f) 2nd molar.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.314-320
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• 2013

With a prevalence rate of 0.01%, the presence of eruption disturbances of mandibular first molar has rarely been in populations. Eruption disturbances of permanent molars have been usually manifested as impaction, primary retention, and secondary retention. The treatments of eruption disturbances are carried out by: periodic observation; surgical exposure; forced eruption after surgical exposure; forced eruption with luxation; surgical repositioning; and extraction. This case report show successfully erupted mandibular first molars by various treatment methods on five patients diagnosed with impaction, primary retention, and secondary retention, respectively. Eruption disturbances of the mandibular first molar can be properly diagnosed with impaction, primary retention, and secondary retention by clinical and radiographic examination at normal eruption time of the mandibular first molar. The treatment should be done synthetically, considering eruption state of affected tooth, the relationship between the affected tooth and the adjacent or opposite tooth, the patient's age, treatment compliance, and economic state.