Shinichi Negishi

Splenic adherent cells, stimulated in vitro, induce the reactive formation of lymphoid follicles and germinal centres in draining lymph nodes after subcutaneous transfusion into syngeneic mice

The reactive formation of lymphoid follicles and germinal centres in lymph nodes, induced by subcutaneous transfer of in vitro activated splenic adherent cells into syngeneic mice, were studied. Adherent cells were obtained by incubating spleen cell suspensions for 24 h and activated by incubating for 1 h in the medium containing keyhole limpet haemocyanin (KLH) absorbed onto alumina. Some of the treated adherent cells were irradiated with 10 Gy x‐rays, while others were either not stimulated or were stimulated with alumina‐KLH but killed by repeated freezing and thawing. Examination of adherent cell smears immunostained with antibodies against, F4/80, Mac‐1, Mac‐2 and NLDC‐145 indicated that many adherent cells displayed macrophage markers but few displayed the interdigitating cell marker. Animals transfused with KLH‐treated adherent cells with or without irradiation showed a marked increase in the number of lymphoid follicles and germinal centres in draining lymph nodes, whereas those transfused with adherent cells which had not been KLH‐treated or which had been killed after KLH treatment displayed no significant change in the number of follicles. These results were interpreted as indicating that following transfusion, antigen‐activated adherent macrophages migrated into the draining lymph nodes and induced the reactive formation of lymphoid follicles and germinal centres outside preexisting follicles.

A discussion of masticatory force mechanics on the median palatine suture of children: Analysis involving a 3-dimensional finite element technique

A statistical analysis covering the past 10 years was carried out using new outpatients since 2001 in the Clinic of Orthodontics of Meikai University Hospital. The materials used in this study were obtained from 2739 patients who sought orthodontic treatment in our clinic. We recorded the monthly number of patients, genders, and chronological and dental ages at the initial visit, along with their addresses, patient referrals, chief complaints, public insurance coverage, and types of malocclusion. Female patients exceeded male patients by 1.9-fold. The most common average age range of the patients’ initial visits were 19–29 years, followed by 7–9 and 10–12. The rate of adult patients was 37.0%, and the most common Hellman’s dental age was IV A. A total of 77.4% of patients lived in an area of less than 20 km, and the largest number lived in Sakado city, where our hospital is located. We found that 66.4% of patients were referred from other hospitals and clinics. Most of these patients were referred from general private dental clinics (47.0%)or other clinics in our hospital (41.5%). The most common chief complaint was crowding, followed by mandibular protrusion and/or crossbite and maxillary protrusion. The rate of public insurance coverage was 20.3%, and patients with jaw deformities totaled 13.1%. Angle Classes I, II, and III were 29.2%, 42.2%, and 27.8%, respectively, showing that Class II patients totaled the highest rate. All these findings demonstrate how our clinics are based on the community’s dental health. An increased number of adult patients indicated the variety of patient characteristics.

Growth change of dental arch form in mixed dentition

To examine the potential dynamic influence of right and left imbalanced occlusal force on the cranial and facial bones, we prepared a 3-dimensional finite element model with a total of 126,534 nodes and 623,852 elements, which comprised 4 aspects including individual cranial sutures, facial bones, and cranial bones excluding mandibular bones, teeth, and periodontal ligament, according to cranial CT images taken from an adult dried skull. By using this model, we then performed 3-dimensional finite element analysis under the following 2 loading conditions: normal occlusion with right and left equality; and unilateral crossbite where the right side was normal but the left side showed crossbite, that is, where right and left imbalanced occlusal force was evident. In the normal occlusion model, a right and left symmetric stress distribution was observed around the key ridge surroundings as well as in the region covering the maxillary frontal aspect to the buccal bone. In the unilateral crossbite model as well, stress distribution was observed in both right-and left-sided key ridge surroundings as well as in the region toward the maxillary frontal aspect. When the right and left aspects were compared, however, the stress distribution was considerably biased, showing a different pattern of distribution. DOI: 10.1016/j.odw.2010.11.004

Relationship between molar occlusion and masticatory movement in lateral deviation of the mandible

Introduction: The relationship between molar occlusion and chewing patterns was examined in subjects with laterally deviated mandibles. Methods: Twenty‐three patients with mandibular deviation from the midline (4 mm or more) and skeletal Class I (0° ≤ANB ≤4°) were divided into 2 groups: normal bite and crossbite. The chewing pattern was classified as normal, reversed, or crossover. Results: The normal bite group had a normal chewing pattern on the affected side 100% of the time and a reversed chewing pattern on the affected and unaffected sides 0% and 7.2% of the time, respectively. Additionally, the normal bite group showed no evidence of a crossover chewing pattern and also had significantly less axial inclination of the mandibular teeth on the affected side compared with the crossbite group; lingual inclination was also evident. The crossbite group had a normal chewing pattern on the affected and unaffected sides 0% and 55.6% of the time, respectively, and reversed and crossover chewing patterns on the affected side 55.6% and 44.4% of the time, respectively. Conclusions: A normal chewing pattern tends to result in lingual axial inclination of the mandibular molars on the affected side, as well as a more consistent chewing pattern. HighlightsChewing was classified into 3 patterns: normal, reversed, and crossover.Subjects with normal bite had a normal chewing pattern.Compared with the crossbite group, the normal bite group had less axial inclination of mandibular teeth on the affected side.Subjects with normal bite had lingually inclined molars on the affected side.Normal chewing pattern may cause lingual inclination on the affected side and more consistent chewing patterns.

Relationship between developmental change in mandibular dentition and maxillary dentition, and also in the palate

The purpose of this study was to investigate the features of dentofacial morphology and occlusion in patients who had experienced orthognathic surgery to treat mandibular protrusion. A questionnaire survey was performed in 2006 at the department of orthodontics in 29 dental schools and 2 private orthodontic practices. The subjects (n = 1,482) were patients who had been diagnosed as dentofacial deformities in the past 5 years. Those with mandibular protrusions (mandibular protrusion group n = 1,072) were divided into the following three categories: surgical, borderline, and orthodontic camouflage, and dentofacial features were examined by cephalograms and dental casts. Patients who had had a skeletal Class I malocclusion were served as a control group. The most common dentofacial deformity was a mandibular protrusion. Surgical cases had severe mandibular protrusion, lingually inclined mandibular incisors, molar Class III relationship, and mandibular deviation compared with borderline cases. In the multiple-logistic regression analysis comparing the mandibular protrusion group and control group, the following factors showed a large odds ratio, i.e. IMPA, U1 to FH, Wits appraisal, overjet, overbite, anteroposterior molar relationship, and mandibular dental midline deviation. OurresultssuggestedthatANB,Witsappraisal,andoverjetcould be useful indexes in diagnoses of mandibular protrusion. Moreover, not only these anteroposterior factors, but also vertical (overbite)andhorizontal (mandibulardeviation) factorsaffected the decision-making process for the application of orthognathic surgery. However, further investigations, including nonsurgical Class III cases, are required for presenting definite criteria of borderline cases to treat with orthognathic surgery.