• Title, Summary, Keyword: Mandible

Search Result 2,197, Processing Time 0.047 seconds

The Effect of Mandible Position on Proprioception and Range of Motion during Neck Stabilization Exercise using a Sling (슬링을 이용한 목 안정화 운동 시 아래턱 위치가 고유수용성감각과 관절가동범위에 미치는 영향)

  • Chae, Jung-Byung;Jung, Ju-Hyeon
    • PNF and Movement
    • /
    • v.16 no.1
    • /
    • pp.115-123
    • /
    • 2018
  • Purpose: The aim of this study was to investigate the effect of mandible position on proprioception and range of motion (ROM) during neck stabilization exercise using a sling in healthy adults. Methods: The subjects were randomly assigned to either a sling exercise and mandible open group (n=10) or a sling exercise and mandible closed group (n=12). The sling exercise-mandible open group and sling exercise-mandible closed group took part in an exercise program for 30min, three times per week for 4 weeks. After each training session, head repositioning accuracy (HRA) and the ROM of the cervical spine were measured. Wilcoxon's test was conducted to verify changes within each group, and the Mann-Whitney U test was performed to examine between-group differences. Results: The HRA of the cervical spine was significantly increased during left rotation and extension in the sling exercise-mandible open group. In addition, there were significant differences in both rotations and extension in the two groups. The ROM of the cervical spine increased significantly during both rotations in the sling exercise-mandible closed group. In addition, there was a significant difference in right rotation and extension in both groups. Conclusion: Cervical stabilization exercise using a sling, with the mandible closed increased proprioception and the ROM of the cervical spine.

Normal and Reconstructed Mandibular Condyle Mechanics

  • Hollister, S.J.;Feinberg, S.E.
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.7
    • /
    • pp.974-981
    • /
    • 2001
  • One approach to reconstructing a damaged mandibular condyle is to replace it with a rib graft. This procedure requires removal of the lateral pterygoid muscle. The rib graft has significantly different shape and mechanical properties than the original condyle. These three factors can be expected to alter mandible (jaw) mechanics. We used voxel-based finite element methods to analysis both normal and a simulated reconstructed mandible using data from the US NIH Visible Human Female. Results demonstrated significant differences between normal and reconstructed mandible mechanics. The reconstructed mandible displaced more than the normal mandible. Stresses in the rib graft were 3 to 4 times higher than in a normal mandibular condyle. Stresses in the rest of the mandible were also higher in the reconstructed case. Further analyses are required to determine how each of the alterations in the reconstructed mandible contributes to the difference in reconstructed mandible mechanics.

  • PDF

A ROENTGENOCEPHALOMETRIC STUDY ON THE CENTRIC OCCLUSION AND THE REST POSITION OF THE MANDIBLE IN THE NORMAL OCCLUSION (두부방사선계측사진(頭部放射線計測寫眞)에 의(依)한 정상교합자(正常咬合者)의 중심교합위(中心咬合位)와 하악안정위(下顎安靜位)에 관(關)한 연구(硏究))

  • Shin, Jai Eui
    • The korean journal of orthodontics
    • /
    • v.8 no.1
    • /
    • pp.59-71
    • /
    • 1978
  • The author compared and analysed the roentgenocephalograms of one hundred Korean adults with the normal occlusion (50 males and 50 females), which were taken on the centric occlusion and the rest position of the mandible respectively for every subject, and then researched the relations among the relaxed muscle of the mandible, lightly touched of the lips, and the position just after the swallowing of saliva, of which 38 among 50 males had the rest position of the mandible. The results are as followings: 1. The anterior facial height increases more at the rest position of the mandible than at the centric occlusion, while the posterior facial height decreases. 2. The mandible moves more backward and downward at the rest position of the mandible than at the centric occlusion. 3. The facial procumbency and the incisor tooth inclination increases more at the rest position of the mandible than the centric occlusion in terms of the facial plane. 4. There are no differences between males and females at the rest position of the mandible and the centric occlusion in the meaning of variation. 5. There are no differences among the three methods from the view of lines and angles of the roentgenocephalogram.

  • PDF

THE STUDY OF ARCH DIMENSIONAL CHANGES BEFORE AND AFTER ORTHODONTIC TREATMENT IN ANGLE CLASS I MALOCCLUSION CASES (Angle씨 I급 부정교합 환자에서 교정치료 전, 후의 악궁크기 변화에 관한 연구)

  • Jeong, Mi;Ryu, Young Kyu
    • The korean journal of orthodontics
    • /
    • v.20 no.1
    • /
    • pp.183-195
    • /
    • 1990
  • The purposes of present study were to identify possible relationships between post-treatment changes and post-retention changes. The patient's models were composed of 58 samples, and were classified non-extraction group (30 samples) and extraction group (28 samples). For each sample the first models were taken prior to the start of treatment, the second models just after the end of treatment, and the third models two years after. The results were as follows: 1. In the cases of non-extraction group, increases were in intermolar width of maxilla, interbicuspid width of maxilla and arch perimeter of mandible during treatment period, but decreases were in the same measurements during post-retention period. 2. In the cases of extraction group, decreases were in intermolar width of mandible, interbicuspid widths of maxilla and mandible, arch length of mandible, arch perimeters of maxilla and mandible during treatment period. 3. Significant decreases were in the irregularity index of both extraction and non-extraction group during treatment period. 4. There were significant differences of arch dimensional changes in intermolar widths of maxilla and mandible, interbicuspid widths of maxilla and mandible, arch lengths of maxilla and mandible, arch perimeters of maxilla and mandible between non-extraction and extraction group.

  • PDF

DYNAMIC 3-DIMENSIONAL FINITE ELEMENT ANALYSIS OF MANDIBULAR FRACTURE MECHANISM (충격하중(衝擊荷重)과 하악골(下顎骨) 골절발생(骨折發生) 기전(機轉)의 유한요소법적(有限要素法的) 연구(硏究))

  • Oh, Seung-Hwan;Kim, Yeo-Gab
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.18 no.3
    • /
    • pp.470-487
    • /
    • 1996
  • The purpose of this study was to investigate the dynamic response of the mandible to impact and provide insight into the fracture mechanism of the mandible, by 3-dimensional finite element method. The finite element model of the mandible was developed and calculated using NASTRAN/XL (MSC co. U.S.A.) and the linear dynamic transient analysis was performed according to the impulsive force direction, force type and impulse time to the mandible. At first, the load was applied on the mandibular symphysis, body, angle and subcondylar area in the horizontal mandibular plane and the computed stress-time histories at 14 locations of the mandible were obtained. Secondly, the impulsive force was directed to the symphyseal area with changing the force magnitude and impulse time, and calculated the node displacement at 8 locations of mandible. The conclusions from from this study were as follows. 1. The appearance of impulsive energy transmission was different to the direction of impulse to the mandible. 2. The impulsive stress and deformation were larger in lingual or medial side than buccal or lateral in the mandible. 3. The velocity, appearance of energy transmission and the fracture pattern in mandible were affected rather impulse time than force. 4. The horizontal impact to the one side of mandible did not have effect on the stress and displacement of contralateral mandible. From the above results, fracture pattern in symphysis can be showed as simple or comminuted, multiple or associated in body and angle and solitary in subcondyle area.

  • PDF

A Case of Mandibulectomy with Partial Preservation of Mandible in Mucoepidermoid Carcinoma Invading Mandible (하악골을 침범한 점액표피양 암종에서 하악 일부를 보전한 변형적 하악 절제술 치험 1예)

  • Hwang Joon-Sik;Lim Young-Chang;Kim Jin-Hwan;Park Il-Suk;Rho Young-Su
    • Korean Journal of Head & Neck Oncology
    • /
    • v.18 no.2
    • /
    • pp.223-226
    • /
    • 2002
  • The segmental mandibulectomy should be performed, if mandiblie invasion is suspected clinically and radiologically. And if tumor is located to mandible very closely or when microinvasion to mandible is suspected, marginal mandibulectomy is recommended. But in segmental mandibulectomy, reconstruction is difficult and cosmetic problem remains. In this case, we performed modified segmental resection of mandible, preserving the inferior margin of mandible, and maintains the continuity of the bone, in mucoepidermoid carcinoma of parapharynx, invading mandible. We reviewed the diagnosis, pathology, and treatment, and report the case with reviews of literature.

COMPARATIVE HISTOMORPHOMETRIC ANALYSIS OF MANDIBLE AND ILIAC BONE ON BONE DENSITY (하악골과 장골의 조직형태계측 비교)

  • Yoo, So-Jeong;Chung, Moon-Kyu
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.38 no.1
    • /
    • pp.12-25
    • /
    • 2000
  • To demonstrate possible influences of general bone density on the mandible, histomorphometric analysis was carried out in mandibles and iliac bones and the correlation of the two bone densities was tested. Comparison of bony density in women and men over 60 years in the mandible was carried out too. Quantitative computed tomography(QCT) was taken in cross-section of mandibles at the same site where histomorphometric analysis was peformed to evaluate the reliability of QCT. The analysis included 40 cadavers with no known diseases affecting the bones. The subjects consisted of 15 females and 25 males with a mean age of 60.3 years. Spearman correlation analysis and Wilcoxon rank sum test was performed. The results were as follows. 1. There was statistically no correlation between the mandible and iliac bone in the values of corrected cortical width(CCW), cortical porosity(POR) in cortex, and total bone volume(TBV), mean trabecular plate thickness(MTPT), mean trabecular plate density(MTPD), and mean trabecular plate separation(MTPS) in trabecular bone. 2. Comparison of women and men over 60 years, men had statistically higher bone density than women except fir POR of buccal and lingual cortex, and WTPD of alveolar trabeculae in mandible. 3. There was statistically significant correlation between TBV of trabecular bone and CT No., but not between POR and CT No. in mandible. According to the results above, there was no correlation between mandible and iliac bone density and between mandibular bony density and age. Further studies are required to support the results. A more noninvasive method to be able to measure the bone density of mandible should be developed and it is necessary to accumulate data on the normal values of bone density of mandible according to age and sex. Further study should be carried out about QCT to measure mandibular bony density using QCT.

  • PDF

Cone Beam Computed Tomography Analysis of Mandibular Anatomical Variation in a Patient with Facial Asymmetry (안면 비대칭 환자에서 Cone Beam Computed Tomography를 이용한 하악골 해부학적 변이의 분석)

  • Park, Seong-Won;Oh, Sung-Hwan;Lee, Jae-In
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.34 no.1
    • /
    • pp.34-40
    • /
    • 2012
  • Purpose: The study was performed to compare patients with anatomical variations in facial asymmetry with patients in the normal range using cone-beam computed tomography (CBCT) and to take the preoperative condition into consideration in the case of a sagittal split ramus osteotomy (SSRO). Methods: The study was conducted on 46 adult patients composed of 2 subdivided groups, an asymmetry group (n=26) and a symmetry group (n=20). The asymmetry group was divided between patients with hemimandibular hyperplasia (HH, n=8) and hemimandibular elongation (HE, n=18). Using cross-sectional computed tomography images, the thickness of cancelleous bone in the buccal area of the mandible, thickness of buccal cortex in the buccal aspect of the mandible, thickness of cancellous bone in the inferior aspect of the mandible, thickness of buccal cortex in the inferior aspect of the mandible, and cross-sectional surface area of the mandible were measured. Results: In the asymmetry group, the cross-sectional area of the mandible including the inferior alveolar nerve positioned on the affected side was significantly different from the symmetry group. Thickness of cancelleous bone in the buccal aspect of the mandible, thickness of cancelleous bone in the inferior aspect of the mandible, and cross-sectional surface area of the mandible in the affected site of hemimandibular hyperplasia was significantly smaller than in the symmetry group. Conclusion: The inferior alveolar nerve runs lower and in a more buccal direction and shows a smaller cross-sectional surface of the mandible in the hemimandibular hyperplasia patients with asymmetry.

The cephalometric study of facial types in Class II division 1 malocclusion (앵글 II급 1류 부정교합자의 안모유형에 관한 연구)

  • Jeon, Yun-Ok;Lee, Ki-Soo
    • The korean journal of orthodontics
    • /
    • v.19 no.1
    • /
    • pp.201-218
    • /
    • 1989
  • This study was focused on the distribution of different facial types of the Class II division I malocclusion groups and skeletal characteristics of the each group and those that anteropsterior relationship of the maxilla and mandible calculated from the analysis of ANB angle and Wits appraisal was quite different from each other, as well. Cephalometric headplates of 140 persons of Class II division 1 malocclusion whose mean age was 11.2 years and 69 persons of normal occlusion whose mean age was 12.2 years were utilize as materials. Measurements were recorded, tabulated and statistically analyzed employing the tracings of the lateral cephalograms, then Class II division 1 malocclusion group was divided into 9 Types according to the angle of SNA and SNB for the anteroposterior relationship of the maxilla and mandible, another 9 Types according to the FH-NPog and SN-MP for the horisontal and vertical relationship, and the other 9 Types according to the ANB and Wits appraisal for intermaxillary relationship as well, with which was based on $Mean{\pm}$ 1SD of those of normal occlusion. The result allowed the following conclusion: 1. $37.1\%$ of population demonstrated maxilla within nounal range and retrognathic mandible to the cranial base, $30\%$ for both maxilla and mandible within normal range, $20\%$ for retrognathic maxilla and mandible and $12.9\%$ of the rest were ananged in Class II division 1 maloccusion groups. 2. Retrognathic mandible and hyperdivergent face accounted for $30.7\%$, mesognathic mandible and neutrodivergent face for $29.3\%$, mesognathic mandible and hyperdivergent face for $16.4\%$, retrognathic mandible and neutrodivergent face for $13.6\%$, mesognathic mandible and hypodivergent face for $10\%$ of population were computed in Class II division 1 malocclusion groups. 3. It was suggested that skeletal Class II malocclusion might be due to anomaly in size and shape of cranial base, underdevelopment of mandible, retropositioning of mandible, underdevelopment of posterior face against anterior face, or any combination of these factors. 4. Population with underdevelopment and / or retropositioning of the mandible showed hyperdivergent tendency of facia profile. 5. The ANB angle and Wits appraisal did not coincide the severity of anteroposterior dysplasia in $35.7\%$ of Class II division 1 malocclusion group each other, and this inconsistency was suggested to be related with mandibular rotation, inclination of cranial base, and anteroposterior position of the maxilla.

  • PDF

EXPERIMENTAL STUDIES OF THE EFFECT OF TETRACYCLINE ON GROWTH OF TIBIA AND MANDIBLE IN RATS (Tetracycline이 백서의 경골 및 하악골발육에 미치는 영향에 관한 실험적 연구)

  • Lee, Mi Dae
    • The korean journal of orthodontics
    • /
    • v.5 no.1
    • /
    • pp.33-41
    • /
    • 1975
  • To study the effect of the tetracycline-HCl on the growth of the rats, the author made a daily injection of tetracycline-HCl in the amount of 40mg/kg of body weight to the lactating mother and weanling rats for 7 days. Lactating and weanling young rats were killed at a week intervals and removed tibia and mandible from soft tissues. The effect of the tetracycline on the growth of rats were analysed from the weight, the length of tibia and the size of mandible. The results were as follows: 1. Tetracycline inhibited the growth of young rats. 2. Inhibitory effects were greater ill the weanling group than the lactating group. 3. The inhibitory effect was marked just after the injection of tetracycline-HCl in body weight and after a week in mandible and tibia. 4. The inhibitory effect of growth nab continued for 2-3 weeks in body weight and 3-4 weeks in tibia and mandible. 5. In growth of mandible, the antero-posterior growth was more inhibited than the vertical.

  • PDF