Alveolar bone grows with development of tooth germs and roots; bone deposition occurs with tooth eruption. Bone tion and deposition, and when the balance between them is disrupted, decrease in components undergoes processes ofre=sorpda lern alveolar bone height or excessive bone deposition result. It has been known that repositioning of teeth through orthodontic treatment can cause alveolar bone resorption which result in decreased alveolar bone height, and there have been many studies to evaluate such effects. X-ray films that could be rephated and standardized were chosen in clinical studies, and among them, bitewmg films men used for objective evaluation of changes in alveolar bone level. Twenty subjects, 10 to 13-year- old (average 10) children with C1 I molar key, healthy oral condition, no congenital missing, no periodontal 4domnttal disease, and pre-and bitewing films, were randomly selected for comparison of alveolar bone heigh. Amounts of tooth and changes in alveolar bone heights were analyzed. The following results were obtained: 1. Amount of tooth mmaneit in canine, premolar, and molar regions, changes in tooth axis, and changes in alveolar bone heights were measured, and the mean and median values were obtained. 2. When pre-and post-orthodontic alveolar bone levels were compared, larger changes were noticed in maxilla than mandible. 3. When mesio-distally compared, larger changes were observed in the distal sides of 3D3 and 4M3, mesial sides of 4M3 and 4D3, distal sides of 4D3 and 5M3, mesial sides of 5M3 and 5D3, and distal sides of 5D3 and 6M3. 4. When the amounts of tooth movements(TX, Mand changes in tooth axis(A) were compared, 34TX, 34TY, 34A of both sides in maxilla were greater, and changes in alveolar bone level were greater than any other region.
Axis, Cervical Vertebra ; Bicuspid ; Bone Resorption ; Child ; Humans ; Male ; Mandible ; Maxilla ; Molar ; Tooth ; Tooth Eruption ; Tooth Germ ; X-Ray Film

As people are more concerned about their and medical care. there have been and increasing number of medical disputes due to increased medical demand. In order to prevent and provide solution to currently surging medical accidents and disputes related to orthodontic treatment, in July 1998, the Korean Association Of Orthodontists surveyed 2.200 members of Korean Association of orthodontists on 30 items to recognize the pattern of medical accidents and prevent them. The survey was about accident-related items including personal profiles of members and patients who have undergone medical accidents or disputes, the cause and solution to the accidents, cautions related to members orthodontic treatment, and medical recording and archival. Based on the survey result we analyzed characteristics of medical accidents and disputes in orthodontic area. It is more important to predict and prevent possible medical accidents or disputes based on current situation than to solve them after disputes occur. For this, we should not be negligent in raising treatment proficiency level based on patient-doctor trust and in obtaining new medical information. We should also provide medical environment where patients themselves can decide whether to get treatment after they are offered detailed explanation on diagnosis, treatment procedure, complication, and possible hazard. We should take caution when treating patients and pay attention to charting and maintenance, which is the most fundamental, as well. Also at the Korean Association and disputes, and actions and organizations that can help when accidents and disputes occur.
Diagnosis ; Dissent and Disputes* ; Humans ; Medical Records

Certain malocclusion are associated with specific "facial type," and it is important for the clinician to classify the common facial characteristic of each patient. Because the reaction to treatment mechanics and the stability of the denture is depended upon the analysis of the facial pattern. Basically, there are 3 district facial types or patterns under which almost all malocclusion can be classified. 1. mesofacial is the most average growth. 2. brachyfacial which is a horizontal growth pattern has a week muscle, with dental arch, deep bite. 3. dolichofacial which is a vertical growth pattern has a strong muscle, narrow dental arch, open bite. Brachyfacial pattern show a resistant to mandibular rotation during treatment can accept a more protrusive denture and are prominantly nonextraction, whereas dolichofacial patterns tend to open during treatment require a more retracted denture in order to assure post-treatment stability. Brachyfacial pattern would better treat to use extrusive force system, whereas dolichofacial pattern treat to use intrusive force system with head gear and intermaxillary elastics.
Dental Arch ; Dentures ; Head ; Humans ; Malocclusion ; Mechanics ; Open Bite ; Overbite

The committee of admitted doctors developed a questionnaire regarding medical dispute and distributed it to 1,600 members of Korean Academy of Orthodontics. The questionnaire consisted of three categories and 56 items covering basic information about the doctors and patients who had experienced medical disputes, the cause and workaround of medical accidents, and methods for taking precautions. The present survey showed a similar proportion of responders who had experienced a medical accident compared to the study in 1997. The primary reason for medical disputes was dissatisfaction with appearance. Many doctors felt that they would likely experience a medical dispute at some point. Most disputes were settled by doctors themselves, usually for an amount of less than 5 million Korean won. For some doctors, medical accidents lead to ongoing psychological problems. Responders felt that continuing education for medical dispute is very necessary. These results reveal a need for the association of orthodontists to lead advancements in education and countermeasures for preventing and managing medical accidents and disputes.
Dissent and Disputes* ; Education ; Education, Continuing ; Ethics ; Humans ; Korea* ; Medical Errors ; Methods ; Orthodontics ; Practice Management ; Surveys and Questionnaires ; Risk Management ; Socioeconomic Factors

Although the purpose of orthodontic treatment is to increase the function and esthetics of the jaws along with increasing stability, there are many side effects during the treatment itself, such as root resorption and alveolar bone resorption. Such resorption of the apical root is unpredictable, and may even proceed into the dentin layer. Once the process has begun, it is irreversible. By evaluating the effect of many oral habits, especially that of nail biting, in correlation with the root and the periodontal tissues, the appropriate biomechanics for orthodontic treatment can be taken into consideration, along with the possibility of root resorption and alveolar bone loss during orthodontic treatment, and any legal problems that might occur. Among the male and female patients of the ages 10~15 without skeletal deformity, 63 were chosen as the experiment group with known nail biting habits at time of examination, and within the same age group without nail biting habits as the control. After the orthodontic treatment, number of the experiment group was 31 and the control group was 22. The periapical radiographies of anterior teeth were taken and the assesment of the root length and alveolar bone level were taken before(T1) and after(T2) the orthodontic treatment. The results from this study were as follows : 1. Before the orthodontic treatment, average crown-to-root ratio of the experimental group showed noticeably high values in 4 maxillary incisors and mandibular right central incisor. 2. Before the orthodontic treatment, comparing the root length, maxillary and mandibular right central incisors and both mandibular incisors had a smaller value in the experimental group. 3. Before the orthodontic treatment, comparing and evaluating the alveolar bone loss measured from the cemento-enamel junction to the alveolar bone crest, some crestal bone of the experiment group showed greater loss than the control. 4. After the orthodontic treatment, there was shortening of the root length and loss of the crestal bone in both groups. 5. After the orthodontic treatment, the changes of C/R ratio and the shortening of root length were significantly high in the experimental group. 6. After the orthodontic treatment, the level of alveolar crestal bone showed greater loss in the experimental group.
Alveolar Bone Loss ; Bone Resorption ; Congenital Abnormalities ; Dentin ; Equidae ; Esthetics ; Female ; Humans ; Incisor ; Jaw ; Male ; Nail Biting* ; Root Resorption ; Tooth

The purpose of this study was to find out and evaluate discrepancies between preorthodontic prediction values and actual postorthodontic values and factors contributing to it in 45 patients(17 male, 28 female) who were diagnosed as skeletal Class III malocclusion and received presurgical orthodontic treatment and orthognathic surgery at Yonsei university dental hospital. Lateral cephalograms were analyzed at pretreatment(T1), orthodontic prediction(T2), immediately before surgery(T3) and designated the landmark as coordinates of X and Y axes. The samples were divided according to ALD, upper and lower incisor inclination(U1 to SN, IMPA), COS, extraction, the position of extracted teeth and the statistical significance was tested to find out the factors contributing to the prediction. The results were as follows : 1. Differences between preorthodontic prediction values and actual postorthodontic values(T2-T3) were statistically significant(p<0.05) in the x coordinates of U6mbc, L1x and in y coordinates of U1i, U1x, U6me, U6mbc, L6mbc 2. The accuracy of prediction is relatively higher in horizontal changes compared to vertical changes. 3. The statistical significance(p<0.05) between prediction and actual values is observed more in the landmarks of the maxilla than the mandible. 4. Differences between prediction and actual values of incisor and first molar were statistically significant(p<0.05) according to extraction vs non-extraction, extraction type, ALD in the maxilla and according to ALD, IMPA in the mandible. Discrepancies between preorthodontic prediction values and actual postorthodontic values and factors contributing to the prediction must be considered in treatment planning of Cl III surgical patients to increase the accuracy of prediction. Furthermore future investigations are needed on the prediction of vertical changes.
Humans ; Incisor ; Male ; Malocclusion ; Mandible ; Maxilla ; Molar ; Orthognathic Surgery ; Tooth

In many cases of orthodontic treatment the upper anterior teeth are retracted. Periodontal problems may arise during incisor retraction, if the amount of tooth movement and the amount of remodeling in the anterior cortical bone are not the same. Therefore in this study, to find out the relationship between the amount of tooth movement and the amount of bone remodeling during retraction of the upper anterior teeth, lateral cephalograms of 56 female patients over 18-year-old were taken before and after treatment. Among the 56 patients, two groups were divided according to the type of root movement during retraction. 26 patients mainly moved by tipping and 30 by bodily movement. The cephalograms taken before and after treatment were superimposed upon the true horizontal plane. In the Tip-Group, the horizontal bone remodeling/tooth movement ratio was 1 : 1.63, and in the Torque-Group it was 1 : 1.66. Because the amount of tooth movement and the amount of bone remodeling were not the same in both groups, in the Tip-Group the root apex moved away from the palatal cortical plate and closer to the labial cortical plate, whereas in the Torque-Group the root moved away from the labial cortical plate and closer to the palatal cortical plate. Therefore, there are limitations in the amount of incisor retraction in patients with a very thin anterior cortical plate in the maxilla, and in patients with severe skeletal discrepancies orthognathic surgery should be considered and when orthodontic camouflage treatment is the only possible method, the orthodontist must be aware of the limitations of treatment.
Adolescent ; Bone Remodeling* ; Female ; Humans ; Incisor ; Maxilla ; Orthognathic Surgery ; Tooth Movement ; Tooth*

The purpose of this study was to compare the shear bond strength obtained from ceramic and plastic brackets bonded with various light-cured adhesives and to evaluate their debonded failure sites. Plastic brackets, Transcend 6000, Signature and Starfire TMB brackets were bonded with Orthobond, Light Bond and Transbond on one hundred forty extracted human premolar teeth as manufacturer's descriptions. After thermocycling the brackets were debonded with an Instron universal testing machine and the debonded bracket base surfaces were inspected under stereoscope to evaluate the failure sites. Also the shear bond strength and failure patterns with different curing time and with two different source of light were compared. The results were as follows. 1. There were no statistically significant differences among the mean shear bond strength of Orthobond, Light Bond and Transbond in a same bracket group except Plastic bracket group(p<0.05). 2. The mean shear bond strength of each adhesive with different bracket groups showed statistically significant differences. Starfire TMB showed the highest shear bond strength among the brackets in this study, but there was no statistically significant difference with Transcend 6000 while there was statistically significant difference with Signature.(p<0.05) 3. The various bonding failure patterns were occurred among different bracket groups but most of failure sites were bracket base-adhesive interfaces. 4. There were no statistically significant differences in shear bond strength between the groups with curing time of 10 second and 20 second, and between the groups with two different sources of light as long as sufficient light intensity(above 400mW/cm2) were provided(p<0.05). According to the result, it should be considered in clinical use of ceramic bracket with light-cured adhesives that the shear strengths of ceramic brackets were influenced by the retention from of bracket base as well as the composition of bracket and there was no difference in the shear bond strength among various light-cured adhesives used in this study.
Adhesives* ; Bicuspid ; Ceramics* ; Humans ; Plastics ; Shear Strength ; Tooth

OBJECTIVE: This study was conducted to perform histomorphometric evaluations of the bone surrounding orthodontic miniscrews according to their proximity to the adjacent tooth roots in the posterior mandible of beagle dogs. METHODS: Four male beagle dogs were used for this study. Six orthodontic miniscrews were placed in the interradicular spaces in the posterior mandible of each dog (n = 24). The implanted miniscrews were classified into no loading, immediate loading, and delayed loading groups according to the loading time. At 6 weeks after screw placement, the animals were sacrificed, and tissue blocks including the miniscrews were harvested for histological examinations. After analysis of the histological sections, the miniscrews were categorized into three additional groups according to the root proximity: high root proximity, low root proximity, and safe distance groups. Differences in the bone–implant contact (BIC, %) among the root proximity groups and loading time groups were determined using statistical analyses. RESULTS: No BIC was observed within the bundle bone invaded by the miniscrew threads. Narrowing of the periodontal ligament space was observed in cases where the miniscrew threads touched the bundle bone. BIC (%) was significantly lower in the high root proximity group than in the low root proximity and safe distance groups. However, BIC (%) showed no significant differences among the loading time groups. CONCLUSIONS: Regardless of the loading time, the stability of an orthodontic miniscrew is decreased if it is in contact with the bundle bone as well as the adjacent tooth root.
Animals ; Dogs ; Humans ; Male ; Mandible ; Periodontal Ligament ; Tooth Root

A subperiosteal ganglion has been very rarely reported, since Ollier reported first one in 1864. A subperiosteal ganglion is produced by mucoid degeneration and cyst formation within the periosteum, which results in cortical erosion. The characteristic plain radiolographic appearance of irregular cortical erosion and scalloping, with reactive periosteal bone spicules, has been considered pathognomonic of subperiosteal ganglion. Magnetic resonance imaging is performed to further characterize the soft tissue component of the mass. As in our patient, the characteristic signal intensities of magnetic resonance imaging are especially useful in identifying the lesion as a ganglion and in defining the lobular nature and the anatomical extent. We report here the case of a 35-year-old female who had a sudperiosteal ganglion of the distal radius.
Adult ; Female ; Ganglion Cysts* ; Humans ; Magnetic Resonance Imaging ; Pectinidae ; Periosteum ; Radius*