• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.165-177
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• 1993

Upper canine is important because it protects and maintains the stability of the dental arch and also, joins the anterior with the posterior teeth. The incidence of impaction of upper canine is the second most frequent next to the third molar because it takes a long period of time to develop, and has a complicated path of eruption, and erupts lately. After the age of 10, clinical and radioglaphic examination can be used in revealing the possibility of impaction and efforts should be put to reduce the side effects. To prevent impaction, selective extraction of primary canine at the age of 8 to 9 could be considered and prolonged retention of primary canine in oral cavity should be avoided at this time. Once the impaction is iden, the first stage of the treatment is to lcocalize the lesion by radiographic examination and According to the severity, orthodontic traction or autotransplantation should be considered and comprehensive diagnosis and treatment plan of malocclusion should be established. Generally, labial impaction is due to arch length discrepancy and palatal impaction is due to malposition or morphologic pathosis of lateral incisors rather than arch length discrepancy. In surgical procedure, peridontal problems should be considered and the minimum amount of bone and soft tissue should be reduced and direct bonding method of many attachment methods should be recommended. Especially in traction of labially impacted canine, it should be guided to erupt through the keratinized zone and proper forced magnitude should be applied. The importance of periodontal condition should always be in mind following the patient education to mintain the good oral hygiene at each stage of treatment. Properly managed impacted canine can provide function and esthetic by proper diagnosis and treatment if extraction of canine is not indicated.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.2
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• pp.400-420
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• 1998

We already know that it is very difficult to obtain an "isolated field" for direct bonding during the surgical exposure of unerupted teeth. The aim of this in-vitro study is to simulate the clinical situation of forced eruption and to evaluate the tensile strengths of preligatured button with several types of contamination which can happen during the surgical exposure of unerupted teeth. Four orthodontic direct bonding systems were used. ($Ortho-One^{TM}$, $Rely-a-Bond^{(R)}$, $Ortho-Two^{TM}$, Phase $II^{(R)}$) Each material was divided into four groups(n=20) : Group 1. (Control, no contamination), Group 2. (Rinse etching agent with saline instead of water), Group 3. (Blood contamination of etched surface for 30 seconds), Group 4. (Blood contamination of primed surface for 30 seconds) 320 bovine anterior permanent teeth were divided into the above mentioned 16 groups. Enamel surface was flattened and ground under water coolant. Pre-ligatured buttons were prepared to the same form. (Cut 0.25 ligature wire 10 cm in length. Twist the ligature wire 30 times clockwise. Mark the wire 15mm and 35mm points from button. Make a loop sticking two points together and twist the loop 6 times counterclockwise.) The bonded specimens were stored at $37^{\circ}C$ saline solution for 3 days. Then the tensile strength of each sample was measured with Instron universal testing machine, crosshead speed of 0.5mm/min. The following results were obtained: 1. As compared to control groups (Group 1) of each material, Rely-a-Bond had a significantly lower mean tensile strengths than other material. (p<0.01) 2. In Group 2. of Ortho-One and Rely-a-Bond, the mean tensile strengths decreased about 7.7% and 11.1%, respectively with statistical significances. (p<0.05) 3. In Group 2. of Ortho-Two and Phase II, the mean tensile strengths did not decrease. 4. In Group 3. of Ortho-One, Rely-a-Bond, Ortho-Two, and Phase II, the mean tensile strengths decreased about 60.8%, 56.1%, 60.2%, and 46.0%, respectively with statistical significances. (p<0.01) 5. In Group 4. of Ortho-One and Rely-a-Bond, the mean tensile strengths did not decrease. 6. In Group 4. of Ortho-Two and Phase II, the mean tensile strengths were decreased about 20.95% and 22.28%, respectively with statistical significances. (p<0.01) There were formations of a hump shaped mass from bonding resin under blood contamination which disturbed direct bonding procedure. According to Reynolds, the proper bond strength for clinical manipulation should be at least 45N or about 4.5Kg.F. According to these results, it can be concluded that Ortho-One could be used during surgical exposure of unerupted teeth. In any case, blood contamination of the etched surface should be avoided, but the blood contamination of primed surface of Ortho-One may not decrease bond strength. Just 'blowing-out' is enough to remove blood from primed surface of Ortho-One. You can verify the clean surface of the primer of Ortho-One after blowing out the blood contamination.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.381-386
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• 2010

As the vertical fracture occurs at the various locations following the long axis of a root, treatment method of crown-root fractured anterior teeth is decided according to the depth. If the fracture line is close to the crown, gingivectomy, orthodontic - forced eruption or surgical extrusion of apical fragment could be done. If the line is over 1/3 length of the root, the prognosis is poor and extraction is usually undertaken. However, extraction of maxillary incisor at growing children causes many complications such as esthetic, phonetic problem and alveolar bone resorption. Therefore, preservation of tooth is the highest priority. Recently, intentional replantation with composite resin could be considered as alternative treatment of crown-root fractured anterior tooth. This report presents a patient in mixed dentition with deep vertical crown-root fracture of the maxillary permanent central incisors by trauma. Intentional replantation of the fractured teeth was performed using composite resin. After 2 years, specific clinical symptom has not been found and the patient was satisfied of esthetic result. This method suggests the new technique to preserve a tooth as an alternative to extraction, although it is technically sensitive and the reports of long-term prognosis is insufficient.