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

{"title":"[The effects on upper first molars by the face-bow construction. Consideration of utilizing the strain gauge method and the computer method of structural analysis].","authors":"R Nakamura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The present study was undertaken for the purpose of detecting the influence on upper first molars by the dynamic behavior originated in face-bow construction. Tests were made at occipital pull and cervical pull face-bows utilizing strain gauge method and the computer method of structural analysis. As for the occipital pull face-bow, a short outer-bow 35 mm frontward of a tube was bent 30 degrees upward and be pulled in that direction. As for the cervical pull face-bow, a medium outer-bow flash to tube, parallel to the inner-bow was pulled from 20 degrees downward. These two types of face-bows were divided into 4 types, those with loops at the back end (WL) and to those without loops (NL). In the strain gauge method, the force and moment to tubes was measured and compared with the values obtained from theoretical analysis. And in the structural analysis, the data of deflection was compared with each other. Those results indicated that 1. face-bow shows a different force to the molars and a different phase of deflection, according to the difference of it's force concentrative section. 2. the larger the deflection, the larger the deviation of forces on molars from theoretical values. 3. the way of setting loops against the direction of pull alters the phase of deflection of face-bow and the force on molars. 4. existance of loops at inner-bow affects as follows: (1) Reduction of moment of each type of face-bow. (2) Reduction of vertical force at occipital pull face-bow and it's increase at cervical pull face-bow. (3) Resistance for deflection of face-bows in the case of tractive force for closing loops.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 2","pages":"246-66"},"PeriodicalIF":0.0,"publicationDate":"1989-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13774272","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":"[Hyoid bone position and airway accompanied with influence of head posture].","authors":"M Nagai,&nbsp;A Kudo,&nbsp;I Matsuno,&nbsp;M Yokoyama,&nbsp;J Manabe,&nbsp;S Hasegawa,&nbsp;S Nakamura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The position of hyoid bone has been analyzed using roentgenogram. But, due to the great variability with the change of head posture, the position could not be determined correctly. In the present study, we investigated the influence of head posture to the position of hyoid bone. Subjects consisted of 32 Japanese males, those mean age was 25.8 years. Lateral cephalograms had been taken for each subjects at 5 different head posture. The findings were as follows. 1. Superimposed on SN plane, hyoid bone moved along the line of menton to 4th cervical vertebrae (C4) with the change of head posture. The hyoid bone moved in parallel with the line of 3rd cervical vertebrae (C3) to C4 (cervical plane). In spite of these movements, RH kept an uniform ratio. 2. The distances between sella turcica and hyoid bone and between C3 and hyoid bone, and the angle between menton, porion and hyoid bone, were at constant value. 3. Some measurements included the distance between hyoid bone and menton and the angle between nasion, sella turcica, hyoid bone showed very high correlation with the change of head posture. 4. EpPW1 (the width of airway) and the distance from C4 to hyoid bone showed almost the same change. It means the position of hyoid bone has a great influence on airway.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 2","pages":"214-25"},"PeriodicalIF":0.0,"publicationDate":"1989-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13774269","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 morphological variation of the spheno-occipital complex to the formation of skeletal facial pattern].","authors":"T Saito","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was first to classify the morphological type of spheno-occipital complex and second to verify the relationship between the type of spheno-occipital complex and skeletal facial pattern. Materials used in this study were latelal cephalograms of 341 Japanese female adults. None of the subjects underwent any orthodontic therapy. Data were evaluated by multivariate analysis. The following results were obtained. 1. By the cluster analysis, the spheno-occipital complex was classified into three types, namely Thick type, Average type, and Slender type. 2. By the principal component analysis, it was shown that the classification was made by the factor of the inclination of posterior cranial base as the first component and the factor of the projection of sphenoidal rostrum as the second component. The Thick type group had less inclined posterior cranial base and more projected sphenoidal rostrum. 3. There was little relationship between mandibular pattern and the spheno-occipital complex. 4. The principal component analysis of the skeletal facial pattern showed that the Thick type group showed skeletal Cl. III tendency and the Slender type group showed skeletal Cl. II tendency, but there was no significant relationship between the vertical skeletal facial pattern and the spheno-occipital complex. In conclusion, the spheno-occipital complex was divided into three type groups according to the inclination of posterior cranial base and the projection of sphenoidal rostrum. It was concluded that the spheno-occipital complex has a close relationship to the skeletal facial pattern and contributes to the facial formation.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 2","pages":"226-45"},"PeriodicalIF":0.0,"publicationDate":"1989-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13774270","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":"[Enhancement of enamel crystallinity with gel method during orthodontic treatment. The 1st report: Application of electron probe X-ray microanalyser].","authors":"A Kameda,&nbsp;T Endo,&nbsp;M Yoshida,&nbsp;N Amano,&nbsp;K Oka,&nbsp;K Nagai,&nbsp;S Yasui","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This paper is to review the gel method of strengthening tooth enamel substance around bonded brackets and morphological observations and elemental analyses of the chopped cross section of the three below-mentioned groups were carried out by electron probe X-ray microanalyser (EPMA) for a relative review. Group I: bracket-bonded extracted tooth enamel in application of the silica-hydro gel method. Group II: bracket-bonded extracted tooth enamel in application of the gelatin gel method. Group III: bracket-bonded extracted tooth enamel in application of neither method. The results obtained were as follows: 1) As a result of making morphological observations through secondary electron image and back scattered electron image, the adhesive condition of the brackets and the state of the chopped cross sections were favorable and these combined observation proved effective as a supplementary method of elemental analysis. 2) Through qualitative analyses, Ca, P, F, O, Na, Mg and Cl were recognized as content elements on the experimental side (the non-bracket side) as well as on the control side (the bracket side) from group I through III. 3) In making ultrahigh-speed wide-area surface analyses (elemental concentration map), the incorporation of F was recognized from enamel cuticle to approximately 200 microns in group I and to 50-100 microns in group II, and the distribution of Ca was totally consistent, and P showed the slight downward trend from enamel cuticle to dentoenamel junction. 4) The incorporation of F was acknowledged to be until 150-200 microns on the experimental side of group I and to be until 80 microns on the experimental side of group II by line analyses. 5) As regards F on the experimental and the control side in group I as well as in group II through a quantitative analysis, the experimental side clearly revealed a high concentration of F and acknowledged 1% level to be a significant distinction. From the foregoing results through the electron probe X-ray microanalyser, strengthening tooth enamel substance in vitro by application of the gel method proved to be effective, and the silica-hydro gel method was indicated to be superior to the gelatin gel method.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 2","pages":"193-204"},"PeriodicalIF":0.0,"publicationDate":"1989-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13841017","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 relationship between the movement of molars and the transmitted mechanism of orthodontic forces in extraoral anchorage (2)].","authors":"K Kobayashi,&nbsp;H Arai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The relationship between the movement of molars and the transmission of orthodontic forces were especially studied about the upward pull of the outer bow in extraoral anchorage. Molar movements were theoretically analyzed from horizontal pull to upward angle of 40 degree. The transmission mechanism of the orthodontic force was studied from horizontal pull to 40 degree upward angle on each 5 degree with the holography experiment on a human dry skull. 1. Horizontal pull of the outer bow resulted in distal movement of the molar. The long axis of the molar was tipped distally. The dentofacial cranium transformed to the lower and backward direction. 2. When the outer bow was inclined at an upward angle of about 18 degree, the molar moved bodily to the distal and superior direction. But the dentofacial cranium transformed a little to the lower and backward direction. 3. When the outer bow was inclined from 25 to 30 degree upward angle, the molar rotated to the clockwise direction, and the dentofacial cranium rotated to the counter clockwise. The bending deformation was not observed on the dentofacial cranium. 4. The dentofacial cranium was compressed in the pull direction from 25 to 30 degree upward angle. These directions were clinically interpreted as inhibition of the downward and forward growth of the maxillary bone.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 2","pages":"205-13"},"PeriodicalIF":0.0,"publicationDate":"1989-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13775924","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":"[High construction bite activator treatment of anterior crossbite in mixed dentition].","authors":"M Masunaga,&nbsp;H Tanaka,&nbsp;T Nakago","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We reported two cases of functional Class III malocclusion with a skeletal tendency in mixed dentition, treated by applying an activator with a high construction bite beyond the freeway space. A high construction bite, approximately 8 to 10 mm between upper and lower incisor edges was employed. By increasing the vertical separation of the construction bite to a specific range, the high construction bite intensified the activation of the myotatic reflex in the muscles of mastication as well the passive tension in the stretched perioral muscles through the viscoelastic properties. (Furthermore, the tension which was generated passively from the stretched perioral soft tissues, such as tendon and skin, would join the force). In these two cases, we could efficiently use the active and passive tension of the muscles by using an activator of this type, and gain the effective orthodontic force clinically.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"66-78"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13779404","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":"[Relationship between an inclination of mandibular plane and a morphology of symphysis].","authors":"R Tanaka,&nbsp;H Suzuki,&nbsp;H Maeda,&nbsp;K Kobayashi","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In order to investigate the relationship between inclination of mandibular plane and morphology of symphysis, 225 adult subjects' cephalograms were measured. Measurements of the mandibular and facial morphology were: SN-MP, gonial angle, SNA, SNB, SNP, ramus angle, SN-GN, L1 to MP, U1 to L1 angle, overbite, and overjet. Measurements of the symphysis were: thickness of symphysis, length of symphysis, height of symphysis, grade of mental protrusion, inclination of symphysis, curve of symphysis, and sectional area of symphysis. From these measurements, the inclination of mandibular plane and morphology of symphysis were compared. Then the following results were found: 1. There is negative correlation between mandibular plane angle (SN-MP angle) and thickness of symphysis at point B. There is more negative correlation between mandibular plane angle and thickness of symphysis at the apex. 2. There are no correlations between mandibular plane angle and thickness of symphysis at the base. 3. There is positive correlation between mandibular plane angle and height of symphysis. There is positive correlation between mandibular plane angle and length of symphysis. 4. There is positive correlation between mandibular plane angle and grade of mental protrusion. 5. There is a slightly positive correlation between mandibular plane angle and inclination of symphysis. There is a slightly positive correlation between mandibular plane angle and curve of symphysis. 6. There are no correlations between mandibular plane angle and sectional area of symphysis (bone volume of symphysis).</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"7-20"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13779405","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 morphological study of the cranial base and dentofacial structure of Japanese with Angle Class II, div. 1 malocclusion--as compared with American white with Angle Class II, div. 1 malocclusion].","authors":"K Ishizuka,&nbsp;T Yamazaki,&nbsp;K Inoue,&nbsp;K Kouchi,&nbsp;B Ou,&nbsp;S Namura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to clarify the morphological differences of Angle class II, div. 1 malocclusion between Japanese and American Caucasians by comparing their cranial base and dentofacial morphology. Materials were lateral cephalograms of 61 Japanese (30 males: mean age 12y3m and 31 females: mean age 12y10m) and 67 American Caucasians (27 males: mean age 13y6m and 40 females: mean age 13y) with Angle class II, div. 1 permanent dentition. Results were as follows: 1. The anterior cranial base length in Japanese with Angle class II, div. 1 malocclusion was significantly shorter than that of American Caucasians. 2. The maxillary length in Japanese with Angle class II, div. 1 malocclusion was significantly shorter than that of American Caucasians. 3. Less than SNA, less than SNB and less than ANB showed no significant difference between Japanese and American Caucasians with Angle class II, div. 1 malocclusion. 4. The whole mandibular length in Angle class II, div. 1 malocclusion of Japanese males and American males showed no significant difference. But the mandibular body length of Angle class II, div. 1 malocclusion in Japanese females was significantly shorter than that of American ones. 5. No significant difference was observed in gonial angle when the two groups were studied. 6. As compared with American Caucasians, the backward rotation of the mandible was evidently observed in Japanese with Angle class II, div. 1 malocclusion.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13778585","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":"[Postoperative evaluation of mandibular prognathism corrected by sagittal splitting osteotomy].","authors":"K Fukui,&nbsp;T Takdokoro,&nbsp;T Himuro,&nbsp;T Yamaguchi,&nbsp;T Ohno","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study is to examine short-term postoperative stability of mandibular prognathism subjected to the surgical-orthodontic treatment. Eight skeletal Class III patients (7 females and 1 male) corrected by sagittal splitting ramus osteotomy after preoperative orthodontic treatment. The stable occlusions at six months after the orthognathic surgery were evaluated. Cephalometric radiographs and cephalometric laminagraphs were used as materials. The results were as follows: 1) Surgical changes: Pogonion was repositioned by 9.8 mm in an average. Overjet was increased of 9.1 mm in an average. Condyles were displaced antero-inferiorly in 3 cases. 2) Changes during intermaxillary fixation: Antero-superior rotation of the proximal segments were found. Region of chin moved inferiorly. Upper and lower incisors were inclined lingually. Variation of lower incisor inclination was larged. Condyle was displaced. 3) Changes from immediately before the release of intermaxillary fixation to the first month thereafter: Anterior-displacement of pogonion and antero-superior rotation of the proximal segment were found. Upper and lower incisors were inclined labially and lingually, respectively. Overjet was decreased. 4) Changes from the 1st to the 6th month after the release of intermaxillary fixation: Antero-superior rotation of the proximal segment and anterior displacement of pogonion were found to a slight extent. Upper incisor presented labial inclination and condyle tended to return to its preoperative position. The above results revealed that the aspect of relapse presented different changes between intermaxillary fixation period and after the release thereof. It was suggested to be ascribable to the setting up of the posterior margin of the distal segment in a position susceptible to the influence of soft tissues at skeletal fixation and to the extension of medial pterygoid muscle adherent to the distal segment. Therefore, appropriate retention of Class III elastics after the release there of were judged to be useful as countermeasures against relapse. In order to obtain postoperative stability, appropriate positioning of the proximal segment and countermeasures to the stress of medial pterygoid muscle during operation remain to be required further.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"48-58"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13778588","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":"[Longitudinal study on average craniofacial growth of skeletal C1. III girls in late adolescent period. Possibility of early orthognathic surgery].","authors":"K Sato,&nbsp;J Sugawara,&nbsp;H Mitani","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The growth increments of Skeletal C1. III face during late adolescent period were investigated to estimate the possibility of earlier application of orthognathic surgery. Twenty C1. III Japanese girls, all requiring orthognathic surgery were investigated. Twenty C1. I girls were used as the control. The materials used in this study were lateral cephalometric X rays which were longitudinally taken at the age of 14 and 17 years respectively. Results were as follows: 1. The mean increments of maxilla and mandible showed no significant difference between C1. III and C1. I after the pubertal growth peak. 2. Ossification stage of the 3rd middle phalanx and the radium could be used as the maturity indicators for mandibular growth. Those were more reliable than the appearance timing of the menarche. Results are considered to be useful information for determining the timing of orthognathic surgery for Skeletal C1. III cases.</p>","PeriodicalId":76235,"journal":{"name":"Nihon Kyosei Shika Gakkai zasshi = The journal of Japan Orthodontic Society","volume":"48 1","pages":"21-8"},"PeriodicalIF":0.0,"publicationDate":"1989-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13778586","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}