• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.2
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• pp.173-178
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• 2021

Inferior alveolar nerve (IAN) injury is usually caused by stretching or crushing of the neurovascular structures and postoperative intra-alveolar hematoma or edema after dental procedures. This results in paresthesia in the ipsilateral chin, lip (vermilion border, skin, and mucosa), and labial or buccal alveolar mucosa of the mandibular anterior teeth. However, there are no reports of sensory alterations in the teeth, especially tooth hypersensitivity, after IAN injury. I report a case in which paresthesia of the lower lip and hypersensitivity of the lower anterior teeth occurred simultaneously after the removal of the third molar that was located close to the IAN. In addition, I discuss the reasons for the different sensory changes between the tooth and chin (skin) after nerve injury from a neurophysiological point of view. Since the dental pulp and periodontal apparatus are highly innervated by the inferior alveolar sensory neurons, it seems necessary to pay attention to the changes in tooth sensitivity if IAN injury occurs during dental procedures.

• The korean journal of orthodontics
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• v.12 no.1
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• pp.27-30
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• 1982

The growth changes in position of upper and lower jaws, incisal inclination in relation to inferior cranial base have been described. Twenty five males was studied quantitavely by means of serial cephalometric reontgenogram from seven to thirteen years of age. The findings seem to warrant the following conclusions: 1. Growth change in anteroposterior relationship of upper and lower jaws to the anterior cranial base showed very little change before eleven years of age but axial inclination of incisal teeth tended to become labiaization in relation to the anterior cranial base. 2. kiter eleven years of age, there wasn't nearly labialization of incisal teeth but jaw prognathism occurred a little in relation to the anterior cranial base.

• The korean journal of orthodontics
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• v.52 no.6
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• pp.432-438
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• 2022

Objective: To compare crown-root angulations of the permanent maxillary anterior teeth in skeletal Class I, Class II, and Class III Korean malocclusion patients using cone-bean computed tomography (CBCT) images. Methods: Sixty CBCT images were collected from orthodontic patients archive based on skeletal Class I (0˚< A point-nasion-B point angle [ANB] < 4˚), Class II (ANB ≥ 4˚), and Class III (ANB ≤ 0˚) to have 20 samples in each group. Mesiodistal crown-root angulation (MDCRA) and labiolingual crown-root angulation (LLCRA) were evaluated after orientation of images. Crown-root angulations were compared among Class I, Class II, and Class III groups and among the maxillary anterior teeth in each group. Results: LLCRAs of the maxillary central incisor and the lateral incisor were significantly lower in Class III group than those in Class I group. However, those of the canine showed no significant differences among groups. MDCRAs of the maxillary anterior teeth did not significantly differ among groups either. Conclusions: Our results suggest that skeletal Class III malocclusion might affect LLCRA of the maxillary incisors, especially the central incisor.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.9 no.1
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• pp.19-23
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• 1979

A study was made primarily to investigate vertical and horizontal distortion of the image at the apical region of the dental roots in orthopantomographs. The subjects consisted of two dry skulls with radiopaque materials attached to root surface. Measuring of the width and length of each predetermined point at 23 teeth was performed in dry skulls and radiographic films. The results obtained were as follows; 1. There was overall magnification of image in the vertical dimension. And anterior portion had greater magnification rate than posterior portion, while lower anterior portion had less magnification rate than upper anterior portion. 2. There was reduction of the image in the horizontal dimension of the teeth, because of the position relation between dry skull and image layer of the orthopantomograph. 3. There was a significant difference in distortion rate between the oposite teeth. 4. Cervical portion of the tooth had more decreased rate of horizontal distortion than apical portion.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.4
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• pp.552-560
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• 2000

Purpose : The purpose of this study was to determine proper position and angulation of an implant for immediate implantation. Materials and Method : From the years 1997 to 2000. 52 Denta $scan^R$ views, 22 upper and 32 lower jaw with an average age of 43 and 40 respectively, were investigated, which comprise intact upper and lower 6 anterior teeth and premolars. On the Denta $scan^R$, the optimal placement for the immediated implantation was simulated. The measuring methods included 1) Angulation difference between tooth long axis and alveolar bone process. 2) Angulation difference of long axis between tooth and installing fixture 3) Distance between center of tooth at cervical area and center of fixture. 4) Distance from root apex to the bone limit of vital structure. One sample t-test was used for statistical analysis. Result : The results were as follows. 1) At the maxillary central incisor and lateral incisor, angulation difference of long axis between tooth and installing fixture was respectively 0.5 and 3.2 degrees with the fixture center's palatally positioned 2mm apart from tooth center. 2) At the lower anterior 6 teeth, that was about $-2.8^{\circ}\;to\;-4.6^{\circ}$ with the fixture center's lingually positioned 1mm apart from tooth center. 3) At the maxillary canine and premolar, that was respectively $11.8^{\circ}\;and \;7.2^{\circ}$ with the fixture center palatally positioned $2\sim2.4mm$ apart from tooth center. 4) At the lower premolar area, that was about $0^{\circ}\;to\;2^{\circ}$ with the fixture center's lingually positioned $0.5{\sim}1mm$ apart from tooth center. 5) Distance from root apex to the bone limit of vital structure, at the maxillary anterior and premolars. was the range of 10 to 12mm, and at the mandibular anterior teeth and the 1st premolar, that was the range of 18 to 20mm. Conclusion : The proper implant position of maxillary anterior and premolar teeth is as paralleled as or more buccally angulated than long axis of tooth with the fixture center's palatally positioned. In mandiblular anterior region, long axis of implants is lingully angulated compared with long axis of tooth and in premolar, almost parelleled with long axis of tooth and alveolar process.

• The korean journal of orthodontics
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• v.7 no.1
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• pp.23-29
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• 1977

A 23 year-old female with skeleto-dentoalveolar protrusion of maxilla, minor broken contact points between anterior teeth, and missing of lower 1st molars, has been treated with multibanded edgewise technique. After treatment of 14 months, she has gained functional overbite-overjet relationship and facial harmony due to the retraction of upper anterior teeth. Root resorption was slight. Especially, us ing the space of missed lower 1st molars instead of extracting lower premolars, expected and favorable results were obtained.

• The korean journal of orthodontics
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• v.21 no.3
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• pp.673-683
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• 1991

This research was performed to find out the adaptation patterns of maxillary and mandibular posterior teeth to the changes in relationships of vertical skeletal components, which constitute the skeletofacial complex. For this research, 61 adult malocclusion patients were chosen as subjects according to the Hellman's dental age with normally ranged FMN-A-B angle. These subjects were divided into 4 groups in maxilla and 3 groups in mandible according to mesiodistal inclinations of teeth. Following results were obtained after studying the relationships of the vertical skeletal components between each group. 1. Inspire of the fact that the FMN-A-B angle was within a normal range, the degree of mesiodistal inclinations of maxillary and mandibular posterior teeth showed differences in relation to the anteroposterior relationships of maxilla and mandible. In case where the FMN-A-B angle was large, the mesial inclinations of maxillary posterior teeth showed more increase from the posterior to the anterior, whereas in mandible it showed overall decrease. 2. The degrees of mesial inclinations of mandibular posterior teeth were increased when the angulations of lower facial height, occlusal plane angle and mandibular plane angle were greater. 3. The patterns of mesial inclinations of maxillary posterior teeth were varied according to the angulation of lower facial height. If relatively large, it showed more increase from the posterior to the anterior and it was decreased nearly consistent when the angulation was small. 4. The degrees of mesial inclinations of maxillary posterior teeth were decreased as the lower facial height, palatal plane angle, occlusal plane angle and the mandibular plane angle became greater.

• Journal of the korean academy of Pediatric Dentistry
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• v.10 no.1
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• pp.131-138
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• 1983

381 students including elementary school boys 75, girls 76 & middle school boys 115, girls 115 were examined to study the factors of dental esthetic self-evaluation: as measured by questionnaire & dental examination. The following results were obtained: 1. In the case of the girls, the more severely rotated or displaced the upper anterior teeth were, the uglier they felt themselves. 2. The students showed the tendency to answer that they were satisfied or had no feeling one way or the other even though their teeth were less straight than others. 3. Most of the students could not relate their teeth to the over-all facial appearance. 4. In the case of the elementary-school-boys, they felt themselves ugly when the overjet & overbite were excessive: in the case of the middle-school-girls, they felt themselves ugly when the rotation & displacement of the upper & lower anterior teeth were severe. 5. Angle's classification showed no statistical significancy.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.209-223
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• 2001

At intrusion of upper anterior teeth in patient with periodontal defect, the use of three-piece base arch appliance for pure intrusion is required. To investigate the change of the center of resistance and of the distal traction force according to alveolar bone height at intrusion of upper anterior teeth using this appliance, three-dimensional finite element models of upper six anterior teeth, periodontal ligament and alveolar bone were constructed. At intrusion of upper anterior teeth by three-piece base arch appliance, the following conclusions were drawn to the locations of the center of resistance according to the number of teeth, the change of distal traction force for pure intrusion and the correlation to the change of vertical, horizontal location of the center of resistance according to alveolar bone loss. 1. When the axial inclination and alveolar bone height were normal, the anteroposterior locations of center of resistance of upper anterior teeth according to the number of teeth contained were as follows : 1) In 2 anterior teeth group, the center of located in the mesial 1/3 area of lateral incisor bracket. 2) In 4 anterior teeth group. the center of resistance was located in the distal 2/3 of the distance between the bracket of lateral incisor and canine. 3) In 6 anterior teeth group, the center of resistance was located in the central area of first premolar bracket .4) As the number of teeth contained in anterior teeth group increased, the center of resistance shifted to the distal side. 2. When the alveolar bone height was normal, the anteroposterior position of the point of application of the intrusive force was the same position or a bit forward position of the center of resistance at application of distal traction force for pure intrusion. 3. When intrusion force and the point of application of the intrusive force were fixed, the changes of distal traction force for pure intrusion according to alveolar bon loss were as follows :1) Regardless of the alveolar bone loss, the distal traction force of 2, 4 anterior teeth groups were lower than that of 6 anterior teeth group. 2) As the alveolar bone loss increased, the distal traction forces of each teeth group were increased. 4. The correlations of the vertical, horizontal locations of the center of resistance according to maxillary anterior teeth groups and the alveolar bone height were as follows : 1) In 2 anterior teeth group, the horizontal position displacement to the vortical position displacement of the center of resistance according to the alveolar bone loss was the largest. As the number of teeth increased, the horizontal position displacement to the vertical position displacement of the center of resistance according to the alveolar bone loss showed a tendency to decrease. 2) As the alveolar bone loss increased, the horizontal position displacement to the vertical position displacement of the center of resistance regardless of the number of teeth was increased.

• The Journal of Korean Academy of Prosthodontics
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• v.8 no.1
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• pp.9-14
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• 1968

A total of 11,039 permanent missing teeth and their 2,696 prosthetic replaced teeth in 6,123 Korean patients were selected for this study, Analyzing the data according to age, sex, jaw and the location, following results were obtained. 1. Tooth mortality and replacement were higher in female than in male. 2. Replaced teeth were only 24 percent of missing teeth. 3. More teeth were extracted and replaced on lower jaw in young patients and on upper jaw in old patients. 4. There are no significant difference in right and left sides of both jaws in missing and replaced teeth, respectively. 5. First molar was the highest percentage in both mortality and replacement. 6. Upper tooth mortality and replacement were higher in anterior portion and lower in posterior portion.