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OBJECTIVE: This paper aims to establish a potential reference standard for the process of transition from milk to solid food in infants and preschool children in Japan, using the transitional food process (TFP) scale described by Sakashita et al. The background for variation and delay in the process are also discussed. DESIGN: A randomized sample survey covering entire Japan. SETTING: Mailing self-completion of questionnaires. SUBJECTS: Randomized sample of 14 000 children aged 0-6 y and their family from 13 prefectures in Japan, namely Hokkaido, Aomori, Iwate, Niigata, Tokyo, Saitama, Fukui, Nagano, Nagoya, Hyogo, Yamaguchi, Kagoshima, and Okinawa. METHODOLOGY: Questionnaires requesting the TFP scale and background factors were sent to 14,000 children and families. The percentile ages were calculated. An eating ability index (EAI: number of accepted foods/total number of foods) x 100) was calculated. Regression analysis by analysis of covariance (ANCOVA; SPSS, 1997) was used to determine the influence of background factors on EAI. RESULTS: From the 6747 (48.2%) effective answers received, percentile curves of the acceptability of each food on the scale were drawn, and used as initial reference standards. The 50 percentile age range of these 20 standard foods covers from 5 to 42 months after birth. The sensitive period for increasing the acceptance of foods in children was between 6 months and 2(1/2) y of age. ANCOVA regression model (R2=0.605) showed that EAI was mostly influenced by age (P=0.000), followed by feeding style (P=0.000), infant food preparation (P=0.000), information source (P=0.000), and birth order (P=0.003). The dominant cause of digestive system problems was shown to be infection, not too-hard food. It seems that breast feeding, bottle feeding with chewing-type nipples, and the manner of preparing infant foods from the family table promote the progress in acceptance. Children whose mothers followed the information given in books or magazines showed a slower progress. CONCLUSIONS: It seems appropriate to use this reference standard in the study of the transitional process from milk to solid food in infants and preschool children in Japan.

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The purpose of this study was to clarify the mechanical properties of 42 brands of nickel-titanium alloy orthodontic wires from 9 manufacturers by conducting three-point bending tests under uniform testing conditions. Manufacturers included A-Company, Hoya Medical, Lancer, Ormco, Rocky Mountain, Sankin, Tomy (GAC), TP, and 3M/Unitek. Cobalt-chrome, and titanium-molybdenum alloy wires were also tested as a reference for comparison of force levels. All reported data were recorded during the unloading process to simulate the force that a wire exerts on a tooth as it is moved into the dental arch from a position of malocclusion. The following results were obtained for the nickel-titanium wires tested. (1) Among the 0.016 inch round wires tested under a maximum deflection of 1.5 mm, the difference between the smallest (Copper nickel-titanium 35) and the largest (Aline) load values was 136 g. For the 0.016 x 0.022 inch rectangular wires tested, the difference between the smallest (Copper nickel-titanium 40) and the largest (Aline) load values was 337 g. (2) The change in load between 1.5 and 0.5 mm of deflection was examined to clarify the superelastic properties of the wires tested. For the 0.016 inch wires, 17 wire brands produced a load difference of less than 100 g, and two brands produced a difference of at least 100 g (Aline and Titanal = 100 g). For the 0.016 x 0.022 inch wires, 15 brands produced a load difference of less than 100 g, and eight brands produced a difference of over 100 g. The smallest and largest load differences were 3 g (Copper nickel-titanium 35) and 200 g (Aline). (3) The majority of the samples with a smaller load difference between deflections of 1.5 mm and 0.5 mm in the unloading process were found among super-elastic wires, while samples with a larger load difference were predominantly found among work-hardened wires. Compared with cobalt-chrome and TMA wires, nickel-titanium alloy wires exert significantly less force. However, the amount of force varies greatly from brand to brand. Consequently, when using nickel-titanium alloy wires, brands must be selected carefully by taking into consideration the severity of the malocclusion and the stage of orthodontic treatment in each case. It is the intent of this study to offer clinicians an unbiased guide for the selection of appropriate nickel-titanium alloy wires.

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The aim of this study was to investigate how the thickness of the masseter muscle relates to the maxillofacial morphology, including the thickness of alveolar process in the mandibular incisor region, and the thickness of the mandibular symphysis. The subjects consisted of 80 adult male volunteers (mean age: 23 years 8 months). The relationship between masseter muscle thickness and the maxillofacial skeleton was investigated by measuring the former by ultrasonography and the latter by roentgenographic cephalometry. The data were initially analysed using a multiple regression analysis. Thereafter, correlation coefficients were obtained by a simple regression analysis. The following results were found: 1. The thickness of the masseter muscle (mean +/- SD) was 15.8 +/- 3.0 mm in the relaxed state and 16.7 +/- 2.7 mm at maximal clenching. 2. Masseter muscle thickness was negatively correlated with the mandibular plane angle. 3. Masseter muscle thickness was positively correlated with the mandibular ramus height (Cd-Go), and the thickness of the alveolar process and that of the mandibular symphysis. It is therefore suggested that masticatory function influences the morphology of the mandible.

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We recently reported that Merkel cells in the normal palatine mucosa of adult rodents are highly polymorphic. In order to ascertain whether or not this polymorphism is also evident in the human oral mucosa, palatine mucosae from cadavers without oral diseases and perilesional palatine mucosae of patients with pleomorphic adenoma were examined by immunohistochemistry using an antibody against cytokeratin 20. Findings showed that Merkel cells in the human normal palatine mucosa were polymorphic, and a number of irregular-shaped Merkel cells (dendritic Merkel cells) with apparent cytoplasmic projections were present among typical oval to round Merkel cells. The mucosa usually contained a small number of oval to round Merkel cells residing in ectopic places such as prickle and granular cell layers. On the other hand, the slightly inflamed perilesional palatine mucosa contained an increased incidence of dendritic Merkel cells. Ectopic Merkel cells were rare in the perilesional palatine mucosa. Characteristics of dendritic Merkel cells were examined using specimens from perilesional palatine mucosae by means of immunohistochemistry and electron microscopy. It was shown that every dendritic Merkel cell and most roundish Merkel cells in the perilesional mucosa lacked innervation. Electron microscopy suggested that dendritic Merkel cells release secretory granules from the tip of the cytoplasmic process and the basal cytoplasm towards the lamina propria mucosae, in a manner resembling the case of similar cells in rodents.

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Our pervious electron microscopic studies indicated that Merkel cells (MCs) in the gerbil palatine mucosa were polymorphic, possibly reflecting different function. In order to verify and extend this evidence, the shape of and the innervation to MCs in the palatine mucosa of six different species of rodents including the Mongolian gerbil and the rat were examined by immunohistochemistry and transmission electron microscopy. Immunohistochemistry using anti-cytokeratin 20 (CK20) antibody revealed that in the gerbil palatine mucosa, approximately half of MCs were dendritic. Confocal laser scanning microscopy after double labeling with anti-cytokeratin and anti-PGP 9.5 or anti-Na+/K(+)-ATPase beta 1 subunit antibodies indicated that most of the dendritic MCs (DMCs) in these mucosae were free of innervation. Electron microscopy showed that all species of rodents examined contained abundant dendritic MCs as well as roundish (oval to round) MCs (RMCs) with typical innervation. Secretory granules of the RMCs were usually concentrated at the synaptic site, whereas those of the DMCs tended to accumulate in the tips of the cytoplasmic processes and in the cytoplasm facing the basal lamina. Some MCs showed features intermediate between those of the RMC and DMC. These results indicate that MCs in rodent palatine mucosae are consistently polymorphic, and that DMCs may represent a distinctive subset with specific, presumably including endocrine and paracrine, functions different from those of RMCs.

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It was reported that the activity of the masticatory muscles is reduced in bottle fed babies. The effects of chewing type bottle teats distributed in Japan on masticatory muscle activity were evaluated. Myoelectric activities of the masseter muscles of 12 babies bottle fed with chewing type bottle teats were recorded and analyzed by the same method as in the previous study. The electromyographic records of 12 breast fed babies and 12 babies bottle fed with regular sucking type bottle teats, which were reported in a previous study, were used as controls. The results show that the masseter muscle activity of babies bottle fed with chewing type bottle teats was similar to that of breast fed babies qualitatively as well as quantitatively. However, activity was visibly different from that of babies bottle fed with sucking type bottle teats, showing significant difference by ANOVA. These data suggest that babies who are ingesting milk from chewing type bottle teats do so with a chewing action similar to that of breast feeding, but very different from that of bottle feeding with sucking type bottle teats. The conclusion was that the chewing type bottle teat is useful for establishing masseter muscle activity.

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Our previous studies suggested that there are significant differences in the growth of the jaw and in muscle activity between breast- and bottle-fed infants. To confirm these differences quantitatively, myoelectric activities of the masseter muscles of bottle-fed babies were studied. Twelve bottle-fed babies, as well as 12 breast-fed babies as a control group, were examined electromyographically during bottle or breast feeds. The duration time of sucking bursts, interval time, cycle time, 0-to-peak amplitude, integrated amplitude of bursts, and integrated amplitude/duration time were measured and the number of bursts over 30 microV was counted. All differences of means were significant by t-test. The masseter muscle activity in bottle-fed babies is significantly reduced. Our results are contrary to previous papers in which almost the same sucking actions in both breast and bottle feeding were reported. The reason why previous researchers thought that the sucking patterns in breast- and bottle-fed babies are essentially the same is considered, and the implications of the differences for dental health are discussed.

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During the last 4 years 73 dental implants with root-coated bioglass to replace one to three teeth in the premolar and molar sites of the mandible were inserted. The bonding ratio between implant and bone was observed clinically 1 year after implantation and installation of the superior structure. This ratio measured 52.4% to 63.3%. An acoustoelectric tester was developed that advanced our skills. The emphasis was placed on a tight fit between implant and surrounding bone.

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The objectives of the present article are to confirm the bone bonding phenomenon of Bioglass (BG) developed by Hench et al., and to observe the singularity of tissue reaction to it. BG and nonreactive silica glass (SG) were implanted in the femurs of rabbits and rats. Histological examination revealed that a relatively acellular zone with little inflammation was formed on BG surface at 1 day after implantation. Neither fibrous tissue nor a distinct boundary was observed between BG and bone after 7 days. On the contrary, a moderate postoperative inflammatory reaction was observed on SG at 1 day, and fibrous tissue was observed between SG and bone after 7 days. From these findings, it was confirmed that BG bonded directly with bone. As the relatively acellular zone observed on BG surface at 1 day was replaced by bone after 7 days, the formation of this zone might play an important role in bone-bonding process. Further research should be focused on the mechanism and biological meaning of bone bonding, for this phenomenon can not be explained by the conventional pathological theory of foreign body encapsulation.

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We evaluated the treatment of left ventricular aneurysm (LVA) caused by myocardial infarction in 44 patients showing cineangiographical features of left ventricular aneurysm. Of the 44 patients, 28 were treated non-surgically (N-S) and 16 were treated surgically (S). Combined aortocoronary bypass graft (ACBG) with aneurysmectomy was performed on 10 patients. Clinical symptoms in LVA patients were angina (34%), congestive heart failure (31.8%), arrhythmia (29.5%), mitral regurgitation (9%), embolism (4%) and septal perforation (2.3%). Distribution of coronary arterial lesions were single vessel (isolated LAD) 29.5% and multiple vessel 59%. Parameters of LV performance measured at baseline in all LVA patients were: CI 3.05 +/- 0.64 L/min/m2, LVEDP 19.0 +/- 3.5 mmHg, LVEDV 200.6 +/- 25.9 ml, diast. wall stress 50.7 +/- 16.8 g/cm2, EF 0.46 +/- 0.15, LV dp/dt/p 17.8 +/- 2.1 S-1, SWI 61 +/- 24 gm/m2. LV performance after surgery showed clear decreases in LVEDP, LVEDV and wall stress (p less than 0.05, p less than 0.02 and p less than 0.02, respectively). In contrast, EF, LV dp/dt/p and SWI increased significantly (p less than 0.02, p less than 0.1 and p less than 0.01, respectively). Comparison of the results of restudy with first catheterization data in the N-S group showed decreases of EF, contractility index and LV dp/dt/p, each reaching p less than 0.1. Residual myocardial motion 1 year after the first cineangiographic study showed a significant decrease (-12.8 +/- 26.7%) in the N-S group, whereas in the S group it significantly increased to (+60.4 +/- 52.7%). A significant difference in coefficient of variation between N-S and S groups was found. Thus, it can be concluded that aneurysmectomy or concomitant myocardial revascularization with aneurysmectomy improves left ventricular diastolic performance and increases residual myocardial viability.

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Left ventricular performance, survival rate and subjective symptoms were analyzed in 243 cases of angina pectoris (147 cases of A-C bypass and 96 cases of medical treatment) and 58 cases of left ventricular aneurysm (21 cases of surgical treatment and 37 cases of medical treatment). Left ventricular performance of angina pectoris were improved in surgical group 6 months after A-C bypass with the significance of p less than 0.02-0.05. However, in the medical group, it showed unchanged or aggravated tendency during average 18 months. Similar results were obtained in the patients with left ventricular aneurysm and furthermore, aggravation of EF and Max dp/dt/p in some medically treated cases was observed. Operative death by A-C bypass was seen in 4 cases (2.7%) and 5 years cumulative survival rate was 92.6% including late death cases died during average 30.1 months in the medical group and its 5 years survival rate was 77.3%. For left ventricular aneurysm, no operative death was recognized and the 5 years cumulative survival rate was 95%. Whereas during average 32.7 months in the medical group, 8 cases died and 5 years cumulative survival rate was 78.6%. Improvement of subjective symptoms after treatment for both ischemic heart diseases was also conspicuous in the surgical group.

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