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市江 雅芳, 半田 康延
1995 年 39 巻 6 号 p.
965-970
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
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第2報レジン部の厚さを9mm一定および9から3mm移行型とした金属床義歯の重合
林 純子, 堀江 康夫, 金子 和幸, 刑部 仁三, 廣瀬 英晴, 西山 實
1995 年 39 巻 6 号 p.
971-979
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
An experiment was carried out to investigate the application of microwaves to resin polymerization of metallic dentures. The relationship between the irradiation output, irradiation time and the polymerization state (surface hardness, internal porosities), and internal temperature of the cured resin was evaluated when the resin thickness was uniform (9 mm) and not (9 to 3 mm). At an irradiation output of 500 W, there was no irradiation time range in which properly cured resin was obtained from all specimens. At an output of 200 W, there was an irradiation time range in which properly cured resin was obtained from all specimens. This was 0.5 minutes (5.5-6.0 minutes) with a uniform resin thickness of 9 mm and 1.5 minutes (6.0-7.5 minutes) with an uneven resin thickness of 9 to 3 mm.
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藤田 優子, 荊木 理恵子, 居相 暢之, 小河 弘枝, 中南 匡史, 桑原 俊也, 高島 史男, 丸山 剛郎
1995 年 39 巻 6 号 p.
980-983
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
Chewing is closely related to occlusion, and occlusion of a specific tooth affects segmental chewing. Therefore, analysis of chewing is supposed to have diagnostic value for assessing occlusion. However, the difference in segmental chewing among various teeth is unclear. Comparison in segmental chewing between before restoration and after restoration was performed in 55 patients who were treated by a single premolar or molar restoration.
The results are summarized as follows:
1. Chewing pattern and chewing speed pattern
1) Premolar restoration had little effect on chewing.
2) First molar restoration revealed a tendency to improve chewing, and second molar restoration demonstrated a tendency to worsen it.
2. Chewing rhythm
Molar restoration showed a tendency to shorten the duration of the occlusal phase.
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シクロホスファゼンモノマーを配合したレジンの硬さおよび耐摩耗性の検討
石上 恵一, 武田 友孝, 大木 研一, 福士 賢治, 大木 一三
1995 年 39 巻 6 号 p.
984-988
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
Self-curing resin for tooth crowns is widely used in clinical practice. It has been applied to temporary restoration for reconstruction of occlusion, resin splint in splint therapy, which is a method for temporomandibular disorder, and formation on the occlusal plane to maintain and restore the occlusal relation of the plate denture.
However, since the durability of self-curing resin is lower than other dental materials, it is inadequate to maintain and keep stability of the occlusal relation, vertical dimension, durability against attrition and resistance to abrasion due to mechanical friction.
Properties is needed. To improve the hardness and abrasion resistance, cyclophosphazene monomer was combined with 4 commercially available self-curing resin monomers and physical properties were compared.
1. Hardness increased as the amount of the cyclophosphazene monomer was increased.
2. Abrasion resistance improved as the amount of the cyclophosphazene monomer was increased.
3. These results show that the combination of the cyclophosphazene monomer with commercially available self-curing resin monomers improves hardness and abrasion resistance.
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小川 隆広, 古谷野 潔, 築山 能大, 末次 恒夫
1995 年 39 巻 6 号 p.
989-994
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this study was to analyze the mechanism of the disclusion of balancing-side teeth during mandibular lateral movement. Clinical examination was performed, and 59 normal young adults were divided into two groups, disclusion group and non-disclusion group. Lateral movements were measured with the six-degrees of freedom mandibular movement analyzing system, and the cuspla inclination was evaluated on the balancing-side second molars using a 3-dimensional digitizer.
In the frontal plane, the inclination of the working-side canine path was significantly smaller in the non-disclusion group than in the disclusion group, whereas there was no significant difference between the groups in the inclination of the balancing-side condylar path. There was significant difference in the cuspal inclination between the groups ; the cuspal inclination in the non-disclusion group was greater than that in the disclusion group. The results of this study suggest that the inclination of the anterior guidance plays an important role in the occurrence of the balancing-side disclusion during lateral movement, in comparison with the inclination of the posterior guidance, as well as in the occurrence of the posterior disclusion during protrusive movements.
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3次元再構築法の利用
川畑 直嗣, 小野 秀樹, 大塚 昭彦, 福永 知美, 鎌下 祐次, 西 恭宏, 長岡 英一
1995 年 39 巻 6 号 p.
995-1003
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
It is important to diagnose the maxillomandibular relation for the arrangement of artificial posterior teeth. In this study, a new method of diagnosis was developed. The contours of edentulous casts and three ball bearings and their impressions on the occlusion rims were measured by a noncontact type shape-measurement system. Using the measuring data of the casts which were interpolated by spline curves and the tentative plane of occlusion, anatomical alveolar crests were calculated. On frontal sections, the angle between the tentative plane of occlusion and the interalveolar ridge lines were calculated.
The results of analysis, including anatomical alveolar crests of upper and lower casts and interalveolar ridge lines, were displayed on the CRT of a personal computer in occlusal, lateral and front views. As a result, it was suggested that this method was useful in the diagnosis of the maxillomandibular relation to edentulous casts.
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第3報軟質裏装材の粘性が床下組織の応力分布に及ぼす影響
河野 文昭, 永尾 寛, 岡 謙次, 友竹 偉則, 今 政幸, 浅岡 憲三, 松本 直之
1995 年 39 巻 6 号 p.
1004-1009
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
Many soft denture liners have been used to improve comfort of the denture for the patient and to reduce the residual ridge resorption in the clinic. However, the ideal properties of soft denture liner have not been clarified. The purpose of this study was to predict the effect of the viscosity of the soft denture liner on the stress distribution in the supporting structures by using Viscoelastic finite element analysis.
The stresses in the supporting structures became higher as the viscosity of the soft denture liners decreased. When soft denture liners having low viscosity were added to the denture base, higher stresses were observed in the soft tissue and bone. The highest stress was observed in the slope of the buccal side of the residual alveolar bone.
These results indicate that the viscosity of the soft denture liners is an important factor to determine the stress distribution in the supporting structures under the denture during use.
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第5報鋳造条件の違いが鋳造性および陶材焼付強度に及ぼす影響について
清野 豊, 酒井 敏博, 芝 樺彦
1995 年 39 巻 6 号 p.
1010-1017
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
An experimental Co-Cr alloy containing 2% titanium with an additional 0.5% ziruconium was prepared and the castability and bond strength to dental porcelain for castings obtained under various casting conditions were evaluated and/or compared with Dentitan.
The results were as follows:
1. When the vacuum was decreased, internal defects of castings obtained with the experimental alloy were remarkably observed, however, these defects were smaller than those of castings obtained with Dentitan.
2. The experimental alloy showed excellent castability of # 26 sheet wax under all casting conditions.
On the other hand, castability of # 28 sheet wax indicated that casting efficiency was decreased under a lower vacuum condition.
3. In this study, castability of the experimental alloy was equal or superior to that of Dentitan.
4. When casting at 0.7 bar, both the experimental alloy and Dentitan indicated maximum bond strength in this study.
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佐久間 栄
1995 年 39 巻 6 号 p.
1018-1026
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
In order to investigate the effect of the lingual inclination of the tooth used as a posterior abutment tooth of a bridge, the pressure occurring at the surface of the alveolar wall was measured around a mesially or lingually inclined tooth used as an abutment tooth of a bridge in a model.
The results were as follows:
1. The pressure at the side to which the abutment tooth was inclined became greater as the tooth was inclined more steeply, and the pressure was greater around the lingually inclined tooth than around the mesially inclined one.
2. When the abutment tooth was inclined lingually, the pressure on the side to which the abutment tooth was inclined became lesser as the loading point was moved buccally on its occlusal surface from the point coincident with the inclined tooth axis to the point coincident with the vertical axis through the rotating center of the tooth.
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第2報筋活動について
篠ケ谷 龍哉, 田中 泰弘, 袖山 亜紀, 松元 誠
1995 年 39 巻 6 号 p.
1027-1035
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
Electromyographic (EMG) activity was measured in the masseter muscle (Mm), anterior temporalis (Ta) and posterior temporalis muscle (Tp) during maximal voluntary clenching (MVC) and recording occlusal contacts by black silicon method (RBS) on 12 normal subjects with sound dentitions. Intercuspal position (IP), lateral position which was horizontally apart 1 mm from IP (LP-1) and canine's edge to edge lateral position (LP-E) were fabricated using LED mandibular tracking device; MVC was performed at IP and LP-E on all subjects; and RBS was at IP, LP-1 and LP-E on 9 subjects.
Total muscle activity during RBS was about 10% of that during MVC at both IP and LP, but individual variation of EMG pattern exists. Ta and Tp showed significantly greater activity on the working side than the balancing side, while Mm showed no clear difference between the sides during both MVC and RBS at LP. The working side Ta showed significantly less activity during RBS than MVC at LP and was greatly affected by the clenching level, but while the balancing side Tp remained unchanged, activity was hardly affected.
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住吉 圭太, 小川 隆広, 古谷野 潔, 築山 能大, 末次 恒夫
1995 年 39 巻 6 号 p.
1036-1042
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this study was to find the stability of the masticatory movement path in normal subjects. Masticatory movements were measured on 56 normal young adults. The stability of the movement path was calculated as standard deviations of incisal, molar and condylar points at every 10% vertical level on each trajectory.
Incisal and molar points:
1. The stability of anteroposterior component was higher than that of lateral component. The stability of anteroposterior and lateral components was high near the intercuspal position, and became lower as the gape increased.
2. The stability of the closing path (CP) was higher than that of the opening path (OP) at the level of 10-50%. However, the relationship between them was inverted at the level of 70-90%.
3. The anteroposterior stability of the working side molar was higher than that of the incisal and non-working side molar points near the intercuspal range.
Condylar points:
1. The stability of lateral component was higher than that of vertical component, and it changed little as the condylar translation increased. However, the stability of lateral component became lower as the condylar transition increased.
2. There was no significant difference in the stability of anteroposterior and lateral components between OP and CP.
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蛭間 崇善
1995 年 39 巻 6 号 p.
1043-1052
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this study was to compare the measurement accuracy of the condylar position on reformatted sagittal CT with that on sagittal tomography (TG). The CTs were reformatted from the 1 mm thickness/interval coronal scan. The TGs were performed with hypocycloidal motion. Impressions of the joint space were taken in order to estimate the actual dimensions. The errors, differences between the values from the impressions and the values from CTs and TGs, were calculated and analyzed by ANOVA. The results were as follows:
1. The mean measurement error of the condylar position on the CT was 0.1 mm. No statistically significant differences were observed among the CTs reformatted from the coronal scan obtained with the Xray beam projecting at 90°, 80° and 70°C to the F-H plane.
2. The measurement error on the TGs with a mean value of 0.3 mm was larger than that of the CTs. However, one of the 6 TMJs caused a great measurement error on the TG with a mean value of 0.9 mm while the measurement of the other 5 TMJs showed a smaller mean error of 0.1 mm.
These findings suggest that the anatomic morphology of TMJs influence the measurement accuracy on the TGs.
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木村 公一
1995 年 39 巻 6 号 p.
1053-1063
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The establishment of an objective diagnostic method for occlusal splint therapy was attempted by using the pressure pain threshold (PPT) measuring system.
PPT was recorded as the signal on each side at two sites of the temporal muscle and four of the masseter.
The PPT measuring system consisted of a grip switch and an indentation sensor. The sensor was placed on the skin over the involved muscle. When the pressure became painful, the patient released the switch. The highest signal at the time of switch off was recorded as the PPT. This pressure was measured for 340 normal subjects between 15 and 77 years of age and nine CMD patients before and after occlusal splint therapy.
PPT in each the CMD patient before treatment were not within the normal range. However, each PPT after treatment was within the normal range.
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松尾 浩一, 沖本 公繪, 寺田 善博
1995 年 39 巻 6 号 p.
1064-1068
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The effect of occlusal factors, especially balancing contact in stomatognathic dysfunction, was studied by statistical analysis. Then, in order to study the relationship between the canine contact and the molar contact on working side during lateral movement, the subjects were divided into three groups.
U test was used to analyze statistical difference in the incidence of TMJ symptoms between the groups. The results were as follows:
1. The molar contact on the working side may have unfavorable effects on TMJ functions.
2. The tooth contact on the balancing side, excluding the molar, may suppress the effecst due to the molar contact on the working side on TMJ functions.
3. As to the incidence of TMJ symptoms, the group, in which tooth contact includes bilateral canine teeth but excludes the molar, was significantly lower than that in the other groups.
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山賀 保, 薦田 安伸, 糸坂 直志, 野首 孝祠
1995 年 39 巻 6 号 p.
1069-1073
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
A total of 125 people, aged from 38 to 86 years, were examined for exposed root surfaces, root surface caries and caries activity of dental plaque.
Denture wearers and non-wearers were examined in this study. The following results were obtained:
1. The percentages of exposed root surfaces increased in people up to ages 60 to 70. The percentages of root surface caries showed a tendency to be higher in elderly people, especially in their 60's, 70's and 80's.
Caries activity was especially higher in the 80's group. 2. Denture wearers had more exposed root surfaces (p<0.05), and were a little more likely to have root surface caries than non-wearers. Caries activity of denture wearers was nearly the same as that of nonwearers.
3. Teeth with low caries activity did not have root surface caries. The higher the caries activity became, the higher the percentages of root surface caries became. These results indicate that dental plaque related to root surface caries according to caries activity test.
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小久保 裕司, 小林 和弘, 坪田 有史, 岩並 恵一, 石原 正隆, 福島 俊士
1995 年 39 巻 6 号 p.
1074-1081
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The effect of eugenol-containing cements on the bond strength of three composite core resins to dentin were examined both before and after thermocycling.
The following results were obtained.
1. Dentin surfaces after removing eugenol-containing and eugenol-free cements with dental excavator were free of other cements by examining with the naked eye, however, from SEM observation a little cement remained on its surface.
2. The remaining cements on the dentin surface influenced the bond strength of three composite core resins to dentin differently.
3. Clearfil DC Core demonstrated the highest bond strength both before and after thermocycling. This means that Clearfil DC Core is little influenced by eugenol.
4. Core Max II demonstrated comparatively high bond strength before thermocycling, however, after thermocycling it decreased significantly.
5. The bond strength of Clearfil Photo Core was effected by some eugenol-containing cements both before and after thermocycling.
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岩堀 正俊, 澤田 尚昌, 下村 卓也, 谷口 正芳, 山内 六男, 長澤 亨
1995 年 39 巻 6 号 p.
1082-1088
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
A basic and clinical study was undertaken for the assessment of the clinical applicability of silver-added glass ionomer cement as a core material for the construction of abutment. Four kinds of sliver-added glass ionomer cements and one kind of glass ionomer-type base cement were used in the experiments.
Result of elemental analyzing by EPMA, a metal particle combined was 2 kinds of solid silver and amalgam alloy. No differences were found in knoop hardness, compressive strength and surface roughness by the types of cement. The radiopacity of silver-added glass ionomer cement was higher than that of glass ionomer-type base cement. Also no differences were found in the characteristics of cutting with a diamond point. The result of the questionnaire about cutting feeling of silver-added glass ionomer cements was better cut feeling than that of glass ionomer-type base cement.
When silver-added glass ionomer cement was applied to the construction of abutments for vital teeth, the dental pulp did not respond to the cement. When it was cut and hardened, excess cutting did not occur, and the same cutting feeling as when using natural teeth was obtained.
These findings suggest that silver-added glass ionomer cement is a clinically applicable core material for the construction of vital abutments.
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阿部 泰彦, 松浦 尚志, 岡本 耕造, 小村 育弘, 三分一 福展, 上重 守克, 赤川 安正, 内田 眞志
1995 年 39 巻 6 号 p.
1089-1093
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this in vitro study was to evaluate the antimicrobial effects of tissue conditioners containing an antibiotic ceramic, silver-zeolite (ZM)(Zeomic
® AJ 10N, Shinagawa Fuel Co., Nagoya, Japan). Five commercially available tissue conditioners were selected and specimens with ZM (2 wt%) was prepared. Tissue conditioners without ZM and plastic plate were used as a positive control and a negative control respectively.
Staphylococcus aureus FDA 209 P,
Pseudomonas aeruginosa KM 338 and
Candida albicans IFO 1385 were selected as test bacteria. Bacterial suspension (approximately 10
6 cells) was poured onto the materials (plate-shaped, 10×10×5mm) and they were incubated at 37°C for 0, 24 and 48 hours. Then the number of viable bacteria in the suspension was counted as colony forming unit (CFU). These procedures were also carried out for the materials stored in artificial saliva for 1 week. No CFU of
S. aureus, P. aeruginosa and
C. albicans was detected on all ZM containing materials. Only
S. aureus and
C. albicans could form no colony on the positive control materials. Storage in artificial saliva showed no influence on antibiotic effects of these materials. These results indicate that ZM containing tissue conditioners have antimicrobial effects against not only
S. aureus and
C. albicans but also
P. aeruginosa and these effects may persist in saliva.
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動的適合試験材を用いた生理的人工歯排列基準
大久保 力廣, 志和 誠俊, 鈴木 恭典, 花谷 重守, 宮田 孝義, 水野 行博
1995 年 39 巻 6 号 p.
1094-1105
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The proper relation of the muscle pressure surface form and surrounding tissue is of great importance. Physiological arrangement of artificial teeth using the trial fitness material and Remolding is a new technique to form the functional contour of the denture.
In this study, five edentulous patients with different ridge resorption were selected, the extent of tongue space, comfort and function of the complete dentures constructed by the Remolding technique (R-denture) and conventional method (C-denture) were compared.
The results were as follows:
1. The tongue space of physiological teeth arrangement was significantly larger than that of posterior teeth which were set on the interalveolar ridge line.
2. Three of 5 patients evaluated a definite superiority of chewing, speech, stability and inferiority of food accumulation with the R-denture.
3. In selecting a set of dentures for regular use, all 5 patients preferred R-denture.
4. The masticatory movements of R-denture was better balanced than that of C-denture in chewing rhythm.
5. It is suggested from tomographic diagnosis that the triangle area drawn from the maxillary residual ridge crest and mandibular supporting bone is suitable criterion for the arrangement of artificial posterior teeth.
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柿本 和俊, 小正 裕, 権田 悦通
1995 年 39 巻 6 号 p.
1106-1112
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
A clinical examination device for complete denture construction was developed, and its use was investigated. The device was found to be effective for recording and examining the relation between artificial teeth and the alveolar ridge. Additionally, it was confirmed to be possible to make the occlusal rim and to arrange artificial teeth in accordance with the location of the incisive papilla and alveolar ridge. This device also allows fabrication of the base of the model parallel to the occlusal plane.
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咬頭嵌合位における咬合接触部位の検出率について
山口 泰彦, 久恒 泰宏, 木村 朋義, 小松 孝雪, 内山 洋一
1995 年 39 巻 6 号 p.
1113-1120
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this study was to verify whether the examination by using “Dental Prescale®”(Fuji Photo Film Co., Ltd.) could detect the occlusal contacts correctly. Five normal male subjects were instructed to bite black silicone (Bite-Checker®, GC Co., Ltd.) and Dental Prescale®(30 H, R-type) in the intercuspal position at the three levels of clenching force. The ratios of the number of occlusal contacts detected by using Dental Prescale, in comparison with the number of that evaluated by silicone-black method, were calculated and analyzed.
The results were as follows:
1. The rates of occlusal contacts detected by Dental Prescale were 80.9±9.1% at the clenching level of 20% MVC (maximum voluntary contraction), 88.0±6.1% at 40% MVC and 95.5±4.6% at 60% MVC. The rates were significantly increased as the clenching force level became higher.
2. In posterior teeth, the rates of occlusal contacts detected by Dental Prescale were more than that in anterior teeth.
These results lead to the conclusion that medium or higher clenching force is necessary for the examination of occlusal contacts by using Dental Prescale. This examination is more reliable in posterior teeth (especially in molars) than that in anterior teeth, where we sould take care not to fail to notice the occlusal contacts.
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厚みによる色調の影響について
宮島 和臣, 島田 和基, 小見山 信, 高見澤 太郎, 大森 実, 龍 美登世, 桟 淑行, 五十嵐 孝義
1995 年 39 巻 6 号 p.
1121-1131
発行日: 1995/12/01
公開日: 2010/11/26
ジャーナル
フリー
As the first step in analysis of the color tone of IPS EMPRESS, change in color tone of the EMPRESS sample using an ingot material for stain, OI, alone was examined in relation to varying thickness, and the color blocking effect of EMPRESS on the abutment was determined.
1. Among parameters of color tone, L* was highest at a thickness of 0.5mm, showing a decline as the sample became thicker. No marked changes were found in a* or b* although there was a slight tendency of b* toward change in a negative direction.
2. The background color was not blocked sufficiently by EMPRESS, although the brightness difference tended to decrease as the thickness of the sample increased.
3. With regard to the influence of the abutment on the color tone of the EMPRESS sample, the color difference in severely discolored cases became small as the thickness of the sample decreased, although blockage of the background color remained insufficient. When used with reinforing metal materials, Au and Pd, the color difference was small, less than 2.0, as along as the EMPRESS sample was 1.2 mm or more in thickness.
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咀嚼運動計測点としての有効性
熊谷 宏, 平野 恭吉, 水口 俊介, 関田 俊明, 鈴木 哲也, 小林 賢一, 長尾 正憲
1995 年 39 巻 6 号 p.
1132-1141
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
The purpose of this study was to evaluate suitability of the soft tissue on the chin as a reference point in measuring masticatory movements. The movements of the chin and a lower incisor during mastication were measured simultaneously using a real-time measuring system for three-dimensional movements of soft tissues (3-D Auto Tracking System).
The results were as follows
1. Computer-based analysis was developed to divide the whole-chewing period into single stroke and determine the beginning of the opening, closing, occluding phase.
2. The chin movements were 1/60 sec slower than lower incisor movements at the beginning of the opening phase.
3. The chin movements were 1/60 sec faster than lower incisor movements at the beginning of the occluding phase.
The results obtained in this study indicate that the soft tissue on the chin was suitable as a reference point in measuring masticatory movements.
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平野 恭吉
1995 年 39 巻 6 号 p.
1142-1153
発行日: 1995/12/01
公開日: 2010/08/10
ジャーナル
フリー
Lips and cheeks play an important role in masticatory functions. The purpose of this study was to analyze the lip movements of the dentulous subjects with the mandibular movements during mastication using 3-D Auto Tracking System. The subjects were 28 males and 22 females, and 8 types of test-foods (chewing gum, caramel, gummy-jelly, peanuts, cookie, carrot, two sizes of boiled fish paste) were used. The measuring point of the lips was placed on the mouth corner and that of mandibular movements was placed on the surface of the chin.
The length of the trace on each chewing cycle was evaluated as the index of the lip's activity. One sequence of mastication was divided into three (first, middle and last) stages. Time dependent changes of the lip's activity were evaluated statistically.
The results were as follows:
1. During tapping, the mouth corner moved to-and-fro between the rest position and the maximum opening position.
2. On the chewing side, the mouth corner was tear drop shaped, and on the non-chewing side, shuttled simply.
3. The lip's activity during mastication depended on the physical property of the test food.
4. As the mastication proceeded, the ratio of the lip's activity to the mandibular movements increased in all test foods except for gum.
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