No abstract available.

This study was undertaken to investigate the relation between orthodontic force magnitude and the amount of tooth movement. And more light force application for reducing root resorption. Twenty-four rats were divided into three experimental groups(A, B, C) based on force magnitude and application method. Springs of 50g force were applied to A group, spring of 100g force were applied to B group and springs of 25g force were applied to C group initially, and after 4 days springs of C group were changed to springs of 50g force. Two kinds of sentalloy(R) (GAC U.S.A) closed coil spring, 50g and 100g, were used. And we made 25g springs by heat treatment process of 50g spring. Each spring was inserted between the maxillary central incisor and the maxillary left first molar. Amounts of tooth movement were measured everyday by digital caliper(Digimatic(R) , Mitutoyo, Japan) under inhalation anesthesia for 15 days, all rats were sacrificed and histological sample were obtained with Hematoxyline-Eosin stan and Masson's trichrome stain. Following conclusion were made : 1. Group B showed the mean cumulative tooth movement of 2.19+/-0.41mm at 15th day, which was greatest among three groups, followed by group C(2.06+/-0101mm), group A(1.90+/-0.49mm) respectively. However, there was no statistically difference among three groups. 2. All groups showed general tooth movement pattern and A, B, C group finished lag phase at 9th, 8th, 7th day, but three was no statistical significance. 3. Group A, B, C showed root resorption and especially group B showed the most severe root resorption and group C showed milder root resorpting than other groups. According to the above results, large initial force with the development of a fairly widespread hyalinized zone may cause severe root resorption, so initial force should be applied lightly to reduce hyalinized area and eventually root resorption and then increased force will induce efficient tooth movement.
Anesthesia, Inhalation ; Animals ; Hot Temperature ; Hyalin ; Incisor ; Molar ; Rats* ; Root Resorption* ; Tooth Movement* ; Tooth*

Decompression ; Follow-Up Studies ; Head ; Headache ; Humans ; Incidence ; Inflammation ; Jaw ; Joints ; Mandibular Condyle ; Recurrence ; Synovial Fluid ; Temporomandibular Joint

Malocclusion

Female ; Follow-Up Studies ; Headache ; Humans ; Incidence ; Neck ; Neck Pain ; Shoulder Pain ; Temporomandibular Joint

The authors analysed the interpupillary distance and the distance between optical centers in 200 spectacles wearers. The results were as follows; 1. Among the 200 glasses wearers, the cases of hospital prescriptions were 44 persons and the cases of optical shops prescriptions were 156 persons. 2. Hyperopic glasses wearers were 26 persons and myopic glasses wearers were 174 persons. 3. The distance between optical centers was coincided to the interpupillary distance in 26 persons and discrepant in 174 persons. 4. In 115 eyes the prismatic effects were more than 0.5 prism diopter, and maximal prismatic effect was 5.78 prism diopters. 5. The evaluation of the induced horizontal phoria showed that 119 persons had the induced esophoria and 55 persons had the induced exophoria. In 58 persons induced phoria were more than 1 prism diopter. Maximal induced esophoria was 11.55 prism diopters and maximal induced exophoria was 4.30 prism diopters.
Esotropia ; Exotropia ; Eyeglasses* ; Glass ; Humans ; Prescriptions ; Strabismus

Matrix metalloproteinases (MMPs) play an important role in the normal morphogenesis, maintenance, and repair of matrix and also have important functions in pathologic conditions characterized by excessive degradation of extracellular matrix, such as rheumatoid arthritis, osteoarthritis, periodontitis and in tumor invasion and metastasis. In this study, expression of MMP-1 and -2 mRNA in retrodiscal tissue of the temporomandibular joint (TMJ) was examined and compared with magnetic resonance imaging (MRI) and surgical findings. MMP mRNAs in the retrodiscal tissue samples were detected by reverse transcription - polymerase chain reaction. TMJ internal derangement (ID) was categorized as normal disc position, disc displacement with reduction, early stage of disc displacement without reduction (DDsR) and late stage of DDsR. TMJ osteoarthrosis (OA) was classified with normal, mild and advanced OA. The amount of synovial fluid collection was divided into not detected, small, large and extremely large amount on MR T2-weighted imaging. Perforation and adhesion were examined during open surgery of the TMJ. Six out of 37 samples were excluded because of little amount of extracted total mRNA. MMP-2 mRNA was detected whole joints, and so the MMP-2 mRNA seems to be expressed normally in retrodiscal tissue. However, MMP-1 mRNA was expressed in 8 of 31 joints. Frequencies of MMP-1 mRNA expression according to the TMJ IDs, amount of synovial fluid and surgical findings made no significant difference. MMP-1 mRNA was detected more frequently in OA groups (7/16 joints, 43.8%) than in normal bony structure group (1/15,joints, 6.7%). Expression of MMP-1 mRNA in retrodiscal tissue might be related with OA of the TMJ.
Arthritis, Rheumatoid ; Collagenases ; Extracellular Matrix ; Gelatinases ; Joints ; Magnetic Resonance Imaging ; Matrix Metalloproteinase 1* ; Matrix Metalloproteinases ; Morphogenesis ; Neoplasm Metastasis ; Osteoarthritis ; Periodontitis ; Polymerase Chain Reaction ; Reverse Transcription ; RNA, Messenger* ; Synovial Fluid ; Temporomandibular Joint*

No abstract available.
Teratoma*