Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society最新文献

{"title":"[Effects of bite raising on fine structure of condylar cartilage in rats].","authors":"O Honzawa","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The present study was investigated the response in the early stage and the adaptability in the maturation stage of condylar cartilage, when the bite was raised at the molars so that the mandible was continuously displaced posteroinferiorly during the developmental stage. 3-week-old male SD rats were used in this study. Amount of the bite raising was approximately 1 mm at the bilateral first and second molars. The short-term (1, 2, 3 and 4 weeks) and long-term (8, 12 and 16 weeks) effects were histologically examined by electron and light microscopy. 1. On examining the short-term effects, at 2-3 weeks the thickness of the maturative and hypertrophic zones was markedly reduced, and the ratio of cartilaginous cell layer was increased in the fibrous zone and decreased in the hypertrophic zone. Light microscopy revealed a reduction of the cell count in the maturative and hypertrophic zones at 2 weeks, an irregularity of cell arrangement at 3 weeks and a cell-less layer in some areas at 4 weeks. From these findings and the anatomical structure, it is presumed that the brackets exerted a compressive force on the condylar cartilage. 2. Short-term electron microscopic observation disclosed a vacuole-like structure in the cartilaginous matrix and some vacuolation of cell at 3 weeks. This seems to suggest the inhibited growth of mandibular condylar cartilage in the short-term. 3. Throughout the long-term, the thickness and ratio of the cell layer was reduced in the maturative and hypertrophic zones and were increased in the fibrous zone. Light microscopy revealed a decrease in the cell count and poor trabecular formation in the hypertrophic zone. These seem to suggest that, under the present experimental conditions, the mandibular condylar cartilage is also affected by long-term elevation. 4. Long-term electron microscopic observation disclosed in the hypertrophic zone the cells that rather morphologically resembled cells existing in the maturative zone. Disturbance of normal calcification was also observed. These seem to indicate that the growth of mandibular condylar cartilage tended to be inhibited in long-term. The above results suggested that continuous bite raising in juvenile rats caused a compressive force to the condylar cartilage, inhibited the growth relatively fast and continued to exert its effect for a long time, though the effect is diminished with time.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"29-47"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13778587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[The pain response of the tooth caused by placement of a labial archwire].","authors":"T Sakamoto,&nbsp;N Sakamoto","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The incidence of pain and discomfort response of tooth caused by placement of a labial archwire was studied. The pain response was assessed in four degrees of pain index (score 0: no discomfort, score 1: discomfort, score 2: mild pain, score 3: severe pain). Materials consisted of 84 males and females with the permanent dentition from 10 years to 41 years. Results were as follows: 1) Of the 84 cases, 95.24 percent of them suffered from pain (mild pain: 26.19%, severe pain: 69.05%). 2) There was no significant difference in the pain response among the under 12 year old group, the 13 to 19 year old group and the over 20 year old group. 3) There was no significant difference in the pain response among the three kind of labial arch wire (0.014\", 0.012\" nickel titanium alloy wire and 0.015\" braided wire). 4) The pain response was statistically higher in the female than in the male. 5) The pain response was observed in 8.75 percent of cases immediately after placement of archwire, and 31.25 percent 2 hours later, 41.25 percent by the end of the day. In 18.75 percent the pain response was observed next day. 6) Cases were sorted into 4 groups according to their highest score. In the severe pain group, the mean value of the severe pain response was 3.57 days, that of the mild pain response was 5.74 days and that of the discomfort response was 6.26 days. In the mild pain group, the mean value of the mild pain response was 3.68 days, and that of the discomfort response was 4.46 days.(ABSTRACT TRUNCATED AT 250 WORDS)</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"59-65"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13779403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[An easily and immediately releasable intermaxillary fixation appliance for use after the correction of surgical orthognathic cases of jaw deformity or fracture].","authors":"K Tamari,&nbsp;Y Shiratsuchi,&nbsp;S Yokota","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In oral surgery, intermaxillary fixation is routinely applied after surgery in cases of surgical orthognathic correction of jaw deformity or fractures. Intermaxillary fixation requires two conflicting factors: Stiff fixation and quick release in an emergency, as in nausea and vomiting. Conventional methods of intermaxillary fixation require multiple stiff ligation after an operation, but in an emergency these ligations can not be cut quickly to free the airway. We have developed a new fixation method placing a third wire (locking bow) above the upper splint or below the lower splint. The locking bow is hooked onto the splint on the unoperated side and firmly ligated to the splint on the jaw being operated upon. The ligatures can be quickly and easily released by pulling out the locking bow. This can be done by the patient himself or another person. This article describes the principles and clinical application of the method. We have found it to be useful in clinical practice.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"811-4"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14396218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Dental arch form achieved by orthodontic treatment].","authors":"M Aoki,&nbsp;K Soma,&nbsp;F Miura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The objective of this study was to compare the dental arch forms of a control group with normal occlusion to the finished dental arch forms achieved by orthodontic treatment. The data consisted of 185 Japanese males and 275 Japanese females. These sex groups were divided into three groups, i.e., a group treated by extraction of the four first premolars, a group treated by non-extraction method and a control group consisting of individuals with normal occlusion. Findings were as follows: 1. The position of each tooth showed a normal distribution, with a small range of variation in all groups. 2. There were no significant differences in the range of tooth distribution among the three groups in each sex. However, the measurement of the male values were larger than those for the females. 3. In comparison with the other two groups, the transversed width between the same number of teeth of the extraction group had a larger width in the anterior teeth segment and a smaller width in the posterior teeth segment. The non-extraction group had a larger width in all of the teeth segment except for the second molars, than for control group. There were significant differences in all of the teeth between the males and the females. 4. As a result of a qualitative and a quantitative examinations, it was determined that the dental arch forms were almost the same among the three groups for each sex. The dental arch became progressively longer in the following successive order for the extraction group, the control group and the non-extraction group. 5. Except for the intercanine width, the dental arch forms of the Japanese group were wider and longer than that of the Caucasian North American group. In spite of the variation of the genetic background in respect to the differences of the ethnic background and sex, it was confirmed that there were no noticeable differences in the dental arch forms between the orthodontically treated groups and the non-treated group with normal occlusion.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"780-95"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14396216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[A cephalometric study on the similarity of craniofacial morphology between children and their parents].","authors":"A Suzuki,&nbsp;Y Takahama","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This study was performed to estimate genetic influences on craniofacial form and to obtain a method of analysing the characteristics in a child as well as the individual growth prediction in each child. Posteroanterior and lateral cephalographs were used to estimate the morphological similarities of craniofacial form between 150 children and their parents. Subjects consisted of 38 boys and 112 girls who were estimated to mature according to the bone maturity index (B.M.I.) on the hand radiographs and who were older than 13 years chosen from among 3,500 orthodontic patients registered at the University Hospital associated with the Faculty of Dentistry, Kyushu University. The correlation analysis in family, estimation of the sexual linkage, the multi-regression analysis and estimation of the heritability of craniofacial characters were computed. The differences in correlations were also tested between prepuberty and postpuberty craniofacial forms in another 100 children with orthodontic treatment. The results are as follows: 1. The craniofacial form of children was highly correlated with that of their parents. 2. The genetic effects of determining the craniofacial form of offspring by the father were equivalent to those by the mother, but daughters were more affected by parents than were sons. 3. The proportions of multi-regression functions ranged from 3.7 to 34.0 percent. These values are too low to predict the growth of a child. 4. The calculated heritabilities on craniofacial form were from 0.286 to 0.962, with the majority being more than 0.600. 5. The coefficients of correlation between the children and their parents increased with growth, regardless of their orthodontic treatment.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"697-719"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14398748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[The effects of dexamethasone and expansion stress on the osteoblasts in mouse calvarial suture in vitro, with special reference to incorporation of 3H-thymidine and 3H-proline].","authors":"H Nagano","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Behavior of sutures in response to expansion stress are thought to be in parallel with the response of bone to orthodontic tooth movement. To investigate this relation between psychologic stress and osteoblasts during orthodontic tooth movement, the effects of expansion stress and 10(-7) M dexamethasone on sutural osteoblasts of mouse calvaria were examined in vitro. The model consists of a tensile force applied to the mouse sagittal suture. Expansion stress induced the formation of osteoid in the sutural areas, and incorporation of 3H-thymidine and 3H-proline in sutural osteoblasts were found to be stimulated by expansion stress. Furthermore, labelling index of 3H-thymidine in the osteoblasts was also found to be stimulated. On the other hand, dexamethasone inhibited the incorporation, labelling index and matrix formation. Moreover, these induced stimulations in expansion stress were inhibited by 10(-7) M dexamethasone treatment. As described above, dexamethasone, which is a synthetic glucocorticoid, inhibited the incorporation of 3H-thymidine and 3H-proline, the labelling index of 3H-thymidine, and the matrix formation in sutural osteoblasts that were stimulated by expansion stress. Therefore, also during orthodontic tooth movement, increased secretion of glucocorticoid that is stimulated by psychologic stress may inhibit the proliferation, cell differentiation, and matrix formation of osteoblasts in periodontal ligaments.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"734-45"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14396212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Stress distribution in mandible induced by occlusal force in different horizontal mandibular positions].","authors":"T Ishida,&nbsp;K Soma,&nbsp;F Miura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The objective of this study was to investigate the stress distribution in the mandible induced by occlusal forces in a various different horizontal mandibular positions identified as neutroclusion, distoclusion, mesioclusion, and laterally shifted occlusion. A three dimensional Finite Element Method (3D-FEM) was applied to an artificial model of a simulated mandible constructed as a homogeneous, isotropic and elastic body. This model was divided into 480 elements with 785 nodes. The right and left heads of the mandibular condyles and the occlusal surfaces of the posterior teeth of the model were restrained. These restraints acted against the loading of the masticatory forces which consisted of a pair of masseter, temporal, and also the lateral and medial pterygoid muscles. The stress distributions analyzed by 3D-FEM were graphically demonstrated on a three dimensional display system. The data obtained were summarized as follows: I. Neutroclusion (1) Tensile stress appeared along the anterior border of the ramus, and compressive stress appeared along the angular portion of the ramus. (2) Compressive and tensile stress appeared on the external and the internal surfaces of the anterior portion of the mandibular body. II. Distoclusion and mesioclusion (1) As the position of the mandible was moved distally, the absolute values of the stress tended to increase on the same areas which is the external and the internal surfaces of the anterior portion of the mandibular body. (2) Compressive stress which appeared on the occlusal surfaces of the posterior teeth was very great in distoclusion. At the same time, the stress that appeared on the heads of the mandibular condyle was also great in mesioclusion. III. Right laterally shifted occlusion (1) Tensile stress appeared along the left sides of both of the left and right rami, and compressive stress appeared along the right side of both of the left and right rami. (2) A great amount of stress appeared on the left occlusal surfaces of the posterior teeth and on the left portion of the mandibular body. From these results, it was determined probably that the mandibular morphogenesis was influenced by a series of stress factors which were induced by the forces of the masticatory muscles.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"767-79"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14396215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Morphological relationship between maxillary sinus and skeletal facial type].","authors":"S Kurita,&nbsp;K Sato,&nbsp;H Fukazawa,&nbsp;H Mitani","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to investigate the variation of the morphology of maxillary sinus in relation to the skeletal facial type. The materials consisted of lateral cephalometric roentgenograms of 100 adult Japanese females. Nine features representing the form of maxillary sinus were selected and the principal component analysis was carried out to determine the characteristics of sinus morphology. The following results were obtained. The form of maxillary sinus seems to mainly influence (or be influenced by) the antero-posterior facial symptom rather than the vertical facial symptom. A case which had a large SNA angle presented a tendency to have a maxillary sinus with a larger antero-inferior portion and more upright anterior wall. The results indicate that the occlusal function may relate to the formation of the maxillary sinus.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"689-96"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14398747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Post-treatment changes of skeletal Class III morphology operated by orthognathic two-jaw surgery].","authors":"Y Omori,&nbsp;J Sugawara,&nbsp;T Soya,&nbsp;H Kawamura,&nbsp;H Mitani","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to investigate the dentofacial changes following orthognathic Two-jaw surgery in skeletal Class III patients. The materials consisted of cephalometric head films of 20 patients who had simultaneously undergone Le Fort I osteotomy and mandibular ramus osteotomy. All cases received the pre- and post-operative orthodontic treatment and had the observation periods over than one year after postoperative orthodontic treatment. The cephalometric radiographs were taken at following five stages: 1. Before preoperative orthodontic treatment, 2. Immediately before surgery, 3. After intermaxillary fixation, 4. After postoperative orthodontic treatment, and 5. Posttreatment observation period. The results were as follows: 1. The anteroposterior skeletal relapse was minimum after surgery. 2. The surgical manner of the maxillary vertical displacement did not effect the stability of the upper facial height after surgery. The lower facial height tended to decrease slightly during postoperative orthodontic treatment. 3. The upper and lower incisors showed lingual tipping during intermaxillary fixation, but the upper incisors tipped labially during retention period. In conclusions, Two-jaw surgery was considered to be quite effective for the correction of skeletal Class III malocclusions especially with the maxillary deficiency.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"720-33"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14398749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Correlations between masticatory performance in chewing gum method and occlusion as well as dento-facial morphology].","authors":"T Hirose,&nbsp;G Ito","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In order to examine the characteristics of the chewing gum masticatory test, the amount of sugar elution, the chewing time and the amount of sugar elution per second were measured in 109 young adults (93 males and 16 females), after 70 strokes of mastication. Their sex differences, differences among various occlusions, correlations with occlusal areas of the buccal teeth and correlations with roentgen cephalometrics were analyzed. 1. There was no sex difference in the amount of sugar elution. However, chewing time was shorter and the amount of sugar elution per second was higher in males than in females. 2. Compared with the normal occlusion group, the amount of sugar elution was significantly lower in the crowding and anterior cross bite groups (Inoue's classification), and in the Class III malocclusion group (Angle's classification) in males. The amount of sugar elution per second was also significantly lower in the crowding and anterior cross bite groups. However, significant differences could not be found for chewing time. 3. The amount of sugar elution per second was significantly correlated with occlusal areas in males and total samples. 4. The amount of sugar elution was significantly correlated with less than ANB and less than L 1 to MP in males, with less than L 1 to MP in total samples. The chewing time was significantly correlated with S-N, N-Me, N-ANS, S'-Ptm' in females. The amount of sugar elution per second was significantly correlated with less than SNA and less than L 1 to MP in males, and with A'-Ptm', Cd-Go, Go-Pog', Cd-Gn, less than SNA, less than L 1 to MP, less than MP-SN and gonial angle in total samples. 5. It is concluded that the chewing gum masticatory test is highly correlated with occlusion and dento-facial morphology. In particular, amount of sugar elution per second was thought to be a useful measure for masticatory performance in clinical orthodontics.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"47 4","pages":"746-56"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14396213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}