Gifu Shika Gakkai zasshi = The Journal of Gifu Dental Society最新文献

It is well known that fibronectin adheres to various oral bacteria and shows affinity to various components. Thus the existence fibronectin which is present in the salivary flow, acquired pellicle and dental plaque, was investigated in used acrylic resin dentures with a direct immunohistochemical fluorescent technique using antihuman fibronectin goat serum which was labeled with fluorescein isothiocyanate (FITC). It was found that fibronectin frequently was present on the surface of acrylic resin dentures.

The root apex values given in the manufacturers' introductions of 5 electronic measuring devices were compared with the mean values measured by each device in the following cases: a) The tip of file was at the apical constriction in the experimental tooth model. b) The tip of file was between 0 mm and -2.0 mm from the root apex in the vital teeth and the pulpless teeth. In the experimental tooth model, when the tip of file was at the apical constriction, the mean values measured by each device except EM were lower than the root apex values given in the manufacturers' introductions of each device. In the case of the vital tooth, when the tip of file was between 0 mm and -2.0 mm from the root apex, the mean values measured by EM-S II and EM were similar to the values given in the manufacturers' introductions of these devices, but not to those obtained by the other devices. Measurements of the pulpless tooth by each device revealed mean values lower than the values given in manufacturers' introductions for the root apex.

A clinico statistical and pathological study was made on 21 cases of the sialolithiasis patients who has been examined at the Department of Dentistry and Oral Surgery, Nagoya National Hospital between April, 1978 and December 1988. There were more male patients than female patients (12 males and 9 females) with a male to female ratio of 1.3:1. According to age group the majority (28.6%) were in their youngest was 17 years old, and the oldest was 72 years old. The left to right ratio was 1.4:1. The earliest visit was made 5 days after onset and the longest was 11 years. The majority was seen within one month (28.6%). The medical institution with which the patient consulted most often prior to visiting our department, was the private dentist's which accounted for 52.4% of all institutions. In the radiograph of the salivary gland tissue extracted together with the salivary calculus, slight lymphocyte cellular infiltration, moderate atrophy of the acinus and fibrous degeneration, and chronic sialitis such as ductus dilatation and others were observed.

The method of pressure force in crown cementing was examined. Continuous occlusal force was always supported by the patients' personal occlusal force in cementing crowns. We found that continuous occlusal force continuously decreased as the occlusal force increased, and the decreasing morphologies were classified into four types, 'Rapid decrease', 'Step-wise decrease', 'Intermediate decrease' and 'Gradual decrease'.

In vivo plaque formation on implant materials was studied. When different implant materials were set on the gingiva, the number of adhering viable bacteria depended on material surface properties 4 hours after setting, but not 48 hours after setting. The formation of pellicle-like thin layers and subsequent covering by lamellarly formed plaque were observed on the surfaces of all materials. Streptococcus species were predominant at the 4-hour setting time but anaerobes increased at the 48-hour setting time; this was common to all materials. The results indicate that surface properties of the implants influence early bacterial adherence, but do not influence bacterial flora or plaque maturation. The subgingival microflora at the neck of implants with clinically normal peri-implant tissues was compared with that at the neck of natural teeth. The bacterial isolates were classified based on their biochemical characteristics. For the spirochaetes, the number was counted directly under light microscopic observation. The most predominant bacterial species was Streptococcus, followed by Actinomyces, Neisseria and then Capnocytophaga at both sites. The ratio of spirochaetes in the microflora was extremely low for both the implant and natural tooth. Such a bacterial distribution pattern closely resembled the hitherto-reported distribution of bacteria existing in a healthy gingival crevicular. This suggested that the microflora in plaque at the neck of a normal implant is basically similar to that at the neck of a natural tooth. In conclusion, plaque formation on implant materials was not influenced by their surface properties in actual oral cavity.

This study concerns the effects of various prosthetic apparatus on speech perception. In this study we analyzed not only the first and second formant frequencies (as have often been studied previously) but also the third formant frequencies, and the three formant frequencies en masse. Our study demonstrated that of the six kinds of prosthetic apparatus we examined, the least effective apparatus was the L.S. type, while the most effective was the M.P. type.

Cytotoxicity of Palfiqu Bonding agent including Universal and Catalyst was examined by a cell culture study using HeLa cells. The Catalyst was cytotoxic to the cell, but Universal revealed no such cytotoxicity. This depended on time and concentration of materials immersed in culture medium.

This study was examined the relationships between the condition of dentition of lower third molar and malocclusions and shape of mandibles, and to predict eruption for third molars by their relationships. Data were obtained from 90 degrees and 60 degrees rotated cephalometlic radiographs, orthopantomographic radiographs, mandibular occlusal films and gnathostatic models of 101 males showing a complete permanent dentition anterior to the second molars and who had not had extraction lower their molars and orthodontic treatments, were selected from 147 dental students at Asahi University. they were divided into 8 groups by condition of lower third molar dentitions. Bilateral presence of lower third molar occurred in 69.3% and unilateral in 20.8% on 60 degrees rotated cephalometlic radiographs. Bilateral eruption or half eruption occurred in 24.7% and impaction in 44.6% on gnathostatic models. Coronal arch length of erupted cases was longer than that of impacted cases. A apired t-test revealed the significant difference (p less than 0.05). Over bite of impacted cases were deeper than that of erupted cases (p less than 0.05). Arch length discrepancy of presented and impacted cases were larger. There were normal occlusions in each group. Most mal-occlusions were prognathia, second to deep bite, bi-maxillary. The most frequent lower arch conditions were crowding (65%). I. M. P. A. of bilateral impacted cases were langer. Mandiblar length (Cd-Pog) of erupted cases were longer. The distance from Xi-point to the distal surface of second molar was border at 25mm for lower third molar eruption.

Dissolution and remineralization behaviors of self-setting apatite cement is organic acids and synthetic saliva and the effect of barium apatite (BaAp)on physicochemical and mechanical properties of the apatite cement were investigated. One-week solubility of several types of apatite cement was considerably smaller than that of commercially available dental cements in 1 mM of acetic, lactic and citric acids (pH4.0 at 37 degrees C). For example, the one-week solubility in citric acids was less than 4.5%. To investigate the dissolution behavior of the apatite cement in detail, two types of 45Ca labeled apatite cement were prepared. In one, the seed apatite was labeled with 45Ca(45Ca-HAp cement) and in the other the matrix apatite was labeled with 45Ca through use of 45Ca-DCPD (45Ca-DCPD cement). Solubility, estimated from the concentration of 45Ca released in 1mM of the organic acid was approximately zero for 45Ca-HAp cement, whereas the solubility of 45Ca-DCPD cement was similar to that of unlabeled cements. This suggests cat dissolution of the matrix apatite governs dissolution of the set cement. In synthetic saliva, the solution phosphate decreased with time once the set cement was introduced to the solution, whereas the solution calcium increased. The former finding suggests that some phosphate compounds precipitated in the synthetic saliva and the latter finding indicates that some portion of the set cement dissolved. The thermodynamic analysis of the solution compositions strongly suggests that remineralization is a major process and dissolution a minor one. In fact, in systhetic saliva labeled with 45Ca having a degree of supersaturation with respect to apatite comparable to rest saliva, 45Ca concentration in solution decreased once the cement pellet was introduced. This finding clearly suggests that the set apatite cement has the ability to remineralize but not to dissolve in synthetic saliva even if the degree of supersaturation with respect to apatite is relatively low. Addition of barium hydroxyapatite (BaAp) successfully bestowed clinically acceptable radio-opacity to the apatite cement. To accelerate the setting reaction which was retarded by Ba2+ released from BaAp at a lower pH during the first stage of spatulation, calcium hydroxyapatite (CaAp) was added to the cement mixture. At 20wt% of BaAp and 20wt% CaAp, the setting reaction proceeded at a neutral or weak alkaline pH, which is one of the most promising aspects of the apatite cement. The cement spaturated at L/P = 0.4 set within 10 minutes and its radio-opacity was comparable to or more than that of tooth enamel.(ABSTRACT TRUNCATED AT 400 WORDS)

The possibility of accurately estimating a tooth crown length and width from measured distance of various face points was examined by using Multiple Correlation Analysis. The multiple correlation coefficient between a tooth crown length and the face point was 0.3137 and the residual standard error was 0.820; that between a tooth crown width and the face point was 0.3917 and its standard error was 0.467, obtained by substituted sample data for multiple regression equation.