-
Takeshi Matsumura, Hideto Kumagai, Hajime Aoki, Shoichi Hashizume, Yos ...
1991 Volume 35 Issue 6 Pages
1075-1081
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
This investigation dealt with objectively estimating the effect of treating denture stomatitis with a denturewash solution containing enzyme to remove
Candida. Two patients were selected for this study, one classified as type II denture stomatitis having Newton's types, and the other being type III. A denturewash solution containing enzyme to remove
Candida from the denture surface was prescribed to the patients.
Candida obtained from the denture plaque ofthe patients with denture stomatitis were incubated at 37°C for 48 hours and its colonies were counted and totaled. The capillaries of the palatal mucosa beneath the denture base were investigated under an oral biomicroscope, and the morphological changes were analyzed with the aid of an image analysis system.
The results were as follows;
1.
C. albicans was isolated numerously in each patients with denture stomatitis. The capillary density increased due to dilatation and elongation of the capillary loops.
2. As the number of
Candida colonies decreased with the use of an enzyme solution, the capillary density also decreased due to contraction and simplification of the capillary loops.
3. Even if
C. albicans were not isolated, the capillaries showed wavy, crossing, branching, and inter communication patterns. So, long term observation seemed necessary in order to heal denture stomatitis.
4. Oral biornicroscopy made it possible to examine the palatal mucosa having denture stomatitis.
View full abstract
-
Tomotaka Takeda, Keiichi Ishigami, Katsuzo Ohki
1991 Volume 35 Issue 6 Pages
1082-1092
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
It is generally known that dentures have decreased in fitness due to various reasons while used for a long period of time. In order to regain fitness, the function of such a dentute is usually restored by means of relining in clinical practice. Materials used in these cases are required not only to precisely reproduce the intraoral form and structure, but to be highly manipulative as well.
“Lightliner
®”, which is recently developed by Sankin Kogyo, Ltd. to solve various problemsof commercially-available materials, is a light-curing paste-type relining material having the following structure as its major characteristic: its monomer component is composed of multifunctional cyclophosphazene monomers having a cyclic structure as its central skeleton and having both hydrophilic and hydrophobic parts in every molecule.
In this study, we applied this material to 30 patients, and then evaluated its external appearances and function, the intraoral state, patients' satisfactoriness, and aesthetic appreciation at 3 months after relining. We obtained very satisfactory results, warranting its clinical application; namely, this relining material was clinically confirmed to be very safe in the body and highly enduring and to have no taste, odor, or amine-like smell, and every operator was fully satisfied with this material for manipulatability.
View full abstract
-
with Special Reference to the Need of Stress Relaxation Mechanism and the Influence of the Connection
Hiroko Hieda, Kimie Okimoto, Yoshihiro Terada
1991 Volume 35 Issue 6 Pages
1093-1101
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Using two-dimensional finite element method, stress analysis was made of a molar bridge with supposed 6 7 defect. Examinations were also made of the need of stress relaxation mechanism for upper structures and the influence of mechanical properties of the implant material in a free-standing position on the stress distribution in bone interfaces. The following information was obtained: The existence of the fibrous connective tissue around the implant body had no influence on the stress relaxation onto the base thereof, but acted as a stress breaker on the periphery thereof. In case of free-standing, either existence or otherwise of the stress breaker scarcely had influence on the stress distribution of the implant. In case of the connection of the implant with natural abutment tooth, stress relaxation in the presence of the stress breaker may lead to a decrease in the stress around the implant, but excess stress relaxation may do damage to natural abutment tooth, making it necessary to take countermeasures thereto.
View full abstract
-
Kuniko Nakashima, Akihito Kawasaki, Naoko Sugimura, Youko Ikematsu, Ku ...
1991 Volume 35 Issue 6 Pages
1102-1112
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
A number of clinico-statistical observation on temporomandibular arthrosis reported that the incidence was the highest in the adults in the twenties. This lead us to pinpoint to the age of twenties and observe the status of stomatognathic system to examine the way temporomandibular arthrosis had developed.
The adults concerened the study were 75 for male and 45 for female in the twenties, each of whom was questioned and tested. Sirognathograph Analysing System was used to the analysis of chewing movements. It resulted in discovering symptoms of temporomandibular arthrosis in 61.2% male and 55.6% female. Clinically, patients presented with the noise in general and the pain especially among female. The patients with symptoms of temporomandibular arthrosis had the normal maximum opening volume, the slightly increased index of DMFT, the reduced Type I pattern in the pattern classification (Kuwahara classification) of frontal projection of chewing movements. The incidence of reverse pattern, crossover pattern or both was high in male patients. Furthermore, the male patients with symptoms of temporomandibular arthrosis had the reduced maximum opening and closing velocity and occlusal phase period, while they gave the increase in the cycle, opening phase period, closing phase period and each coefficient of varia-tion.
View full abstract
-
Case of Abutment Teeth with Reduced Periodontal Supporting Tissue (Part III)-(3-Dimensional Finite Element Analysis of the Posterior Bridge Model)
Kouichi Matsuo, Kimie Okimoto, Yoshihiro Terada
1991 Volume 35 Issue 6 Pages
1113-1124
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
In order to clarify the stress distribution to the supportive tissues of abutment teeth of a fixed-bridge, the finite element method has been frequently used. However, they were actually the two-dimensional analysis of a mesio-distal section of a bridge or the projected results of the three-dimensional analysis on a mesio-distal section. We made the three-dimensional finite-element model based on the bridge of 1st molar defective case, simulating a variety of defective patterns occurring in the bone surrounding the abutment teeth. We then analyzed the stress distribution to a bucco-lingual section of the supportive tissues surrounding abutment teeth under vertical and lateral loadings. The results were obtained as follows.
1. Under vertical loading, the defective bone surrounding 2nd premolar exhibited the reduction of compressive principal stress seemingly induced by the see-saw effect at a bucco-lingual section including the distal root of 2nd molar.
2. With regard to the influence of the increased defective level of bone surrounding abutment teeth, the increase rate of the stress under lateral loading exceeded that under vertical loading.
3. A proportional relation didn't exist between the principal stress to the periodontal membrane of abutment teeth and the quantity or the surface area of residual supportive tissures.
View full abstract
-
Koji Suga, Tatsuo Namikoshi, Zenya Koyama, Takaaki Uchino, Tetsuro Tor ...
1991 Volume 35 Issue 6 Pages
1125-1132
Published: December 01, 1991
Released on J-STAGE: August 10, 2011
JOURNAL
FREE ACCESS
Using a cone-type stud attachment, the relationship between mobility of the abutment tooth and retentive force was experimentally evaluated. Changing the thickness of artificial periodontium and pressure (load) on the retainer, retentive force was electrically recorded. Retentive force (F), retentive time (T) and impulse (I), were measured on it.
The following results were obtained;
1. For the cone-type denture retainer, the retentive force was highly affected with the magnitude of the load in the abutment with thin periodontium (P=0.0123).
2. Both of retentive force (F) and Impulse (I) decreased with increase of periodontal thickness (P<0.0001).
3. Within the range of 1.5mm to 6.0mm thickness of the periodontium, the thicker the periodontium was, the lager a retention bearing index of the abutment tooth (I/F ratio) we found it became (P<0.0001).
4. It was suggested that Impulse (I) might represent a total amount of retentive force to be born by the abutment, and that I/F ratio would be available for planning the RPD, particularly in evaluating the optimal retentive force.
View full abstract
-
Kazushige Ooshio
1991 Volume 35 Issue 6 Pages
1133-1147
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
This study elucidates the parameter of masticatory muscle activities and muscle fatigues in both time and frequency demain. Furthermore the 1/f fluctuation, reported by Johnson and Musha, in muscle figures was demonstrated from the view point of a biological responsibility. The Electromyographic investigation was performed by eleven male students as the subject. Biting forces were devided into three levels as a condition of this electromyographic power spectrum time series, that was, slightly, middle and heavy figuration.
Frequency components of biting power spectra increased the low regions as the biting forces increase. Maximum biting sustainment increased the frequency regions of the spectral powers as the biting time duration increased. At the middle force of biting figures the 1/f fluctuation was represented in the power spectral curves, and the fluctuations faced with a significant difference among three stages of biting conditions. According to the 1/f fluctuation as a biological response, frequency components of the muscle activity power have to select above 100-200 Hz ranges.
View full abstract
-
Masakazu Kurachi, Hajime Ishigami, Akinobu Fujimoto, Sanae Yamada
1991 Volume 35 Issue 6 Pages
1148-1160
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
This study was made to examine if original gingival color of an individual patient in healthy condition can be presumed from the observed data on the color of his gingiva having presented pericoronal gingival redness. The subjects were 50 males (aged 23-31) whose gingivae have been identified as clinically healthy. X, y, V, Bl and f values were determined from raw data obtained by the color measurement of 4 gingival spots near the cervical regions of maxillary central and lateral incisors. Multiple regression analysis was made with x, y and V values of the healthy papillary gingiva as objective variable and with each element of the observed data (twenty-dimensional observed value vector) upon the manifestation of gingival redness, which has bi-graded according to the degree of redness (slight redness, redness), as explanatory variable.
As a result, the analysis of a bi-graded observed data series according to the degree of gingival redness was confirmed to make it possible to presume the original gingival color of the papillary part in healthy condition, suggesting the usefulness for its clinical application.
View full abstract
-
Toshihiro Ogata, Tomoji Matsuura, Yoshizo Okamoto, Takashi Horibe
1991 Volume 35 Issue 6 Pages
1161-1167
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
We experimentally produced three Ti-Ni-Pd-Sn alloys with Ti contents of 5, 10 and 90wt% and examined their properties for the use of titanium alloys as dental prosthetic materials that possess the excellent characteristics of the metal.
1. Mechanical properties of 10 and 90wt% titanium alloys such as the hardness and tensile strength were similar, and were better than those of commercial alloys, but the 5wt% alloy was softer.
2. The bonding strength to porcelain was the greatest in the 10wt% alloy, and the material is considered to be applicable also as an alloy for porcelain.
3. The amounts of Ti and Ni eluted from the alloys were markedly less than those from commercial alloys, and elution of other elements was minimal.
4. These experimental alloys are considered to be clinically useful as dental prosthetic materials.
View full abstract
-
Tomohiko Enomoto, Hiroaki Hanawa, Setsuo Arai, Satoshi Shimamoto, Tosh ...
1991 Volume 35 Issue 6 Pages
1168-1176
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
With the view of selecting test foods for the estimation of the masticatory function of denture wearers, we prepared a list of 60 items of daily food and inquired of 222 denture wearers about the above list.
The following results were obtained:
1. Effective answers were 51.4%(114 wearers).
2. Volunteers (wearers only) estimated their own dentures ‘satisfactory’, ‘take no notice’ and‘dissatisfied’ in 54.4, 27.2 and 18.4% respectively.
3. These 60 items of daily food were indicated in the order of easy masticability in Tables 1, 2, 3 and 4, which made it possible to grasp the condition of daily food intakes by denture wearers.
4. The relationship between the estimation of dentures by these volunteers themselves and the condition of these 60 items of food intakes was made clear.
5. As the above results, we selected 28 items from 60 items of food for a new table that of estimation for denture wearers ‘masticatory function’, and defined a practical use of it.
View full abstract
-
Syuichi Fukunaga, Yoshinobu Kimura, Yasuhiko Takamori, Shigemitsu Hara ...
1991 Volume 35 Issue 6 Pages
1177-1181
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Resin-hydroxyapatite material has been developed to overcome the disadvantages of hydroxyapatite. This material is composed of 75% hydroxyapatite, 15% Bis-GMA and 10% quartz reinforced filler. The purpose of this study was to examine the influence of the material and the constituents; hydroxyapatite, Bis-GMA on surrounding bone tissue histologically.
Cylindrical piece (4mm diameter×10mm length) of each material was prepared, implanted in femurs of six adult mongrel dogs. At 2, 4, 12 weeks after implantation, decalcified histologic sections were examined microscopically.
The results were as follows:
1. The resin-hydroxyapatite or hydroxyapatite at 12 weeks postoperatively showed direct contact with the surrounding bone tissue in most interface region between either material and bone tissue, while in some interface region, fibrous connective tissue existed.
2. Bis-GMA at 12 weeks postoperatively showed fibrous connective tissue free of inflammatory cells in most interface region between the material and adjacent bone tissue, while in some interface region, this material had direct contact with the bone tissue without intervening fibrous connective tissue.
Above results indicated that the resin-hydroxyapatite material was as biocompatible as hydroxyapatite, and suggested that this material would be acceptable for clinical use.
View full abstract
-
Competitive Experiment on 1 Implant to 3 Natural Teeth
Makoto Ogiso, Ceancheng Chen, Pai Tsun Kuo, Tsuneo Tabata, Yasuo Yamas ...
1991 Volume 35 Issue 6 Pages
1182-1194
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
This study compares the degree of ability of Apatite Implant to bear occlusal force of opposing natural dentition. Two pieces of Apatite 2-Piece Impant are placed into monkey's M
2and M
2, after healing from extraction. Four months later, single crowns are cemented to the Implants and the connected-3-crowns are cemented to the antagonistic M
3M
2M
1and IMIM
2M
3. Vertical dimension is raised and only the implants are in cotact with the opposing arch. One month later, the upper and lower implants and antagonistic connected-3-crowns are histologically examined.
Results: Neogenetic bone can be widely observed around the trabeculae and the compact bone which support the implants, in reaction to the excessive occlusal force. And bone remodeling has begun in some parts. There is no abnormal finding around the implants. But the upper and lower antagonistic connected-3-teeth show intrusion and tipping, and some roots are in direct contact with the alveolar wall.
From above, we concluded that the bearing ability of Apatite Implant to the occlusal force is very high.
View full abstract
-
Makoto Takenaka, Syoji Takehana, Takeshi Maruyama, Yoshinori Mukaida, ...
1991 Volume 35 Issue 6 Pages
1195-1204
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
This study was conducted to make clear the extraordinary occlusal contact. The subjects were 16 persons with nomal occlusion and 15 persons with a subjective symptom of TMJ dysfunction. These subjects were recorded intercuspal position and lateral and protrusive interocclusal record by silicone impression materials. They were measured electromyography.
1. For subjects with nomal occlusion, the contact teeth number of intercuspal position was at least 18-teeth, At lateral position these 16 persons had a tendency that canine on working side there was contact and on nonworking side no contact. When the molar on working side had the contacts, the molar on nonworking side had the contacts. At protrusive position they had bilateral incisal contacts.
2. For subjects with symptom of TMJ dysfunction, there were 3 persons that the contact teeth at intercuspal position were less than 11. At lateral position, these 15 persons had more patterns of occlusal contact than 16 subjects with nomal occlusion. And the different patterns were 11 varieties. At protrusive position, these subjects had more patterns of occlusal contact than 16 subjects.
3. In some cases there were relations among the symptons of TMJ dysfunction and the occlusal contact and electromyography.
View full abstract
-
Part 2. Intensifying the conecting rigidity by the improved methods
Yoshimasa Igarashi, Mitsuhiro Asami, Yoshimasa Yoda, Morihiro Kawata, ...
1991 Volume 35 Issue 6 Pages
1205-1213
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
In the first report of this study, we were able to point out the key to diminish the denture dynamics in the free-end saddle R. P. D.'s. That is the connecting rigidity between the abutment teeth and the retainers used. The more rigidly the retainers were connected to the abutments, the less the movements of the retainers were obtained. It was revealed that the main factor to diminish the movement of the retainer had derived from the multi-parallel guiding surface/guiding plate functions. It was advocated that the R. P. P. I.(Rest, bi-Proximal, Plate, Ibar) retainers had special function in reducing the denture mobility with their supreme connecting rigidity in contrast to any other clasp retainers.
In this present study, we tried to enhance the connecting rigidity of the R. P. P. I. retainers to the level of the Cone-Crown telescopes. Good results to the connecting rigidity was obtained by the two improved methods:
1. The precise refractory cast impression material with silicone rubber (Combisil) was effective to the well fitting parallelism of the guiding plates.
2. The cast-on, double casting method using a special material to give the separating film by oxidation was also effective in case of the noble metals.
View full abstract
-
Part 2. The Pressure Sensitivity of the Sensor
Kazuaki Tokumura, Atsushi Yamashita
1991 Volume 35 Issue 6 Pages
1214-1219
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
The purpose of this study was to investigate the accuracy for measurement of the T-Scan system experimentally as a quantitative diagnostic device for occlusion.
The following conclusion can be drawn from this study:
1. The force sensitivity decreased gradually each time the constant pressure was added in the same line on the new ‘hot sensor
®’, and reached plateau at last.
2. The results confirm that the lowest sensitivity areas exist on both sagittal and transverse axes of the sensor and that they coinside in position with the gaps between electrical conductive stripes in the sensor.
View full abstract
-
Part 1. Effect of Water Immersion Time
Hidekazu Takahashi, Mitsuhiro Murakami, Kenji Warita, Tadaharu Kawawa
1991 Volume 35 Issue 6 Pages
1220-1228
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Luting cements were widely tested according to a specification test. With specification tests, specimens are allowed to set sufficiently before testing the procedure. However, in clinical use, oral fluid easily touches the luting media before completely set. The aim of this study was to clarify the effect of water immersion time on zinc phosphate cement properties. This study tested compressive properties (compressive strength, proportional limit, and elastic modulus), solubility (P, Zn and Mg), surface hardness, and analysis of chemical components. Two different P/L ratios of zinc phosphate cement were selected; one was the same as the manufacturer's instruction and the other was a one-third powder reduced ratio of the former. Specimens were immersed immediately after setting, 2 min after setting and 60min after mixing began. The properties tested in this study improved according to the delay of water immersion time. The effect of water immersion time of the manufacturer's instruction P/L ratio was greater than that of the reduced P/L ratio. These results emphasize the importance of moistureproofing during cementation in clinical treatment.
View full abstract
-
Physical factors for penetration
Norio Mukai, Yoshiaki Hata, Kazuko Saito
1991 Volume 35 Issue 6 Pages
1229-1235
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
The penetration by bacteria through dentinal tubules was studied using a device that included portions of bovine anterior teeth. Strain of 4 genera,
Streptococcus mutans, Lactobacillus casei, Staphylococcus aureus and Eschelichia coli were used for the experiment, and effects of hydraulic pressure to the dentin surface on the rate of bactrial penetration were examined.
The MPT
50 for the tested strains was reduced in every case by elevated hydraulic pressure. Under conditions of high or low pressure,
S. mutans showed the slowest penetration among the strains tested.
From these results, it is suggested that the hydraulic pressure against the dentinal tubules have an important effect on bacterial penetration through these tubules.
View full abstract
-
Noboru Kitagawa
1991 Volume 35 Issue 6 Pages
1236-1247
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
The influence of aging and the oral condition on the control of mandibular movements in correspond response to auditory signals have been studied. The subjects were 20 dentulous young adults and 10 edentulous aged persons with complete dentures. They were asked to perform tap-tap movement of mandible in synchronization to auditory signals, which were generated at regular intervals (0.6, 1.3, 2.0, 4.0 time/sec) and given in two ways:(1), Constant signals that were repeated sixty times at a given pace; and (2), Inconstant signals that were first paced slowly and then were gradually increased to a faster pace (0.6-1.3, 1.3-2.0, 2.0-4.0 time/sec). For each sequence, the signals were generated ten times.
The following results were noted:
1. A strong relationship was observed between the synchronized time of the tooth contact with the signal and both the range and the velocity of the mouth opening/closing movement. In each subject, the range of the mouth opening decreased according to the increase in the signal pace. Also, the range and the velocity of the mouth opening/closing movement of the aged were greater than that of the young subjects at each pacing.
2. With both the constant and inconstant signals, the time that the aged took to synchronize their movements was longer than that of the young subjects.
3. In the ability to control the range and the velocity of the mouth opening/closing movement, a significant difference between the aged and the young subjects was found.
View full abstract
-
Nobuyuki Ikuta
1991 Volume 35 Issue 6 Pages
1248-1255
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Pain or fatigue is frequently observed in patients with temporomandibular disorders, which may be due to abnormal circulation. In order to clarify blood flow in masseter muscle, I examined the effects of sustained clenching on muscle blood-flow rates.
For this purpose I used an electrolytic tissue rheometer (RBF-221, Biomedical-Science Co., Japan), which employs a clearance method using electrolytically generated hydrogen gas for the measurement.
Before commencing my experiments, I obtained the proper electrolytic parameters and then proceeded to carry out measurements in a superficial area of masseter muscle before, during and after clenching, on three males. Clenching force was limited to about 30% of maximum, in terms of effective value of electromyographic activity.
Results can be summarized as follows:
1. During clenching, blood flow rates varied, relative to those obtained before clenching.
2. Immediately after clenching, measured values increased by 5.6 [ml/min/100g] on the average, relative to those obtained before clenching.
These changes were in rough correspondence with results obtained earlier by 133Xe clearance method. The amount of increase, however, was less than those cited above, probably due to the difference in length and time of data analyzing period used in electrolytic tissue rheometer, and the amount of clenching force.
View full abstract
-
Akira Saitoh
1991 Volume 35 Issue 6 Pages
1256-1266
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
The purpose of this study is to clarify interocclusal relations between opposing upper and lower molars during lateral excursions. We measured both the shape of occlusal surfaces and jaw movements in three-dimensions. Analytic parameters were as follows:(1) the direction of the movement of lower first molar, in the two lateral occlusal where the incisal point was located 0.5 and 2mm from its location in the intercuspal position (2) the area of the region on the occlusal surface of upper first molar, where the distance from its counterpart was equal to less than 0.3mm (nearest contact region) and 1.0mm (near contact region), in the intercuspal position and the two lateral positions.
Results were as follows: 1) In the 0.5mm-lateral position, no difference was recognized in the area of the nearest contact region between the working and non-working sides 2) In the 2mmlateral position, the area of the same region on the working side was nearly twice as large as that on the non-working side 3) In the 0.5mm-lateral position, the area of the nearest contact region on the non-working side was significantly correlated with the direction of the movement, but that on the working side was not.
View full abstract
-
Mutsuo Yamauchi, Shinji Onda, Eihaku Cho, Machio Shimizu, Masatoshi Iw ...
1991 Volume 35 Issue 6 Pages
1267-1273
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Linear coefficient of thermal expansion (LCTE), linear curing shrinkage (LCS), and marginal sealing of eight commercial core composite materials and one posterior composite resin were investigated in this study.
Micro filler type core composite had a largest LCTE and submicron filler type core composite had smallest LCTE. Nevertheless, exception of micro filler type, there were no remarkable differences of LCTE in composite resins tested.
Posterior composite resin had a largest LCS, following micro filler type core composite, and photo-cured type core composite had a smallest LCS.
Significant inverse correlation existed between filler content and LCTE. No significant correlation observed between filler content and LCS. However, core composites containing a large amount of filler tended to reveal a small LCS.
Micro filler type core composite, had a largest LCTE and LCS, demonstrated high degree of marginal leakage. Submicron filler or photo-cured type core composites, had small LCTE or LCS, revealed low degree of marginal leakage.
View full abstract
-
Mutsuo Yamauchi, Kohji Yamamoto, Akihiko Nigauri, Masatake Nishizawa, ...
1991 Volume 35 Issue 6 Pages
1274-1276
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Antimicrobial action of five commercially avaiable denture cleaning pastes and one tooth paste on
Streptococcus sanguis ATCC 10556,
Staphylococcus aureus 209 P,
Actinomyces viscosus ATCC 15987, Candida albicans ATCC 18804, and
Bacteroides gingivalis clinical were studied.
Tooth paste revealed antimicrobial activity on microorganims tested exception for
C. albicans. All denture cleaning pastes showed good antimicrobial activity on all microorganisms tested than tooth paste.
This result indicates that denture cleaning paste is effective for preventing of denture stomatitis when denture cleaning paste is carefully used.
View full abstract
-
Part 1. Analysis of Antero-posterior Distance of Mandibular Movement
Seiichi Nakashima, Kiyoshi Koyano, Mikio Mizuno, Tsuneo Suetsugu
1991 Volume 35 Issue 6 Pages
1277-1285
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
Few studies have been reported on the kinematic correlation between incisal and condylar paths.
We defined the parameters related to mandibular movement distance and analyzed the correlation between incisal point and condyles statistically in 20 normal subjects with Kyushu University 3-D movement analyzing system.
The parameters are as follows: the incisal parameter “I” is 3-D linear distance of incisal point during mandibular movement. The condylar parameter “C” is the curve length of condylar path and “Cs” is the antero-posterior distance of condylar path projected on the Camper's plane.
As a reault of this study, there were differences between the right and left condyle paths at the point of maximum opening and during protrusive and lateral excursive movements. In each of the above three movements, there was a high correlation between C and Cs. The Cs ratio of protrusion to maximum opening was about 50% and that of lateral excursion to maximum opening was the same. In protrusion we found a notable correlation between Cs and I. This has suggested we could estimate condylar movement from incisal movement stochastically.
View full abstract
-
Effects concerning the Loss of Occlusal and Proximal Contacts
Katsu Sato, Kazutoshi Furukawa, Jun Takebe, Akira Shiraishi, Kanji Ish ...
1991 Volume 35 Issue 6 Pages
1286-1291
Published: December 01, 1991
Released on J-STAGE: August 10, 2010
JOURNAL
FREE ACCESS
In order to examine the three dimensional displacement for those abutment teeth having lost occlusal and proximal contacts, a measuring device was designed enabling one to simultaneously record the mesiodistal, buccolingual, and axial movements. The measurements were taken during a 7 days span, and the amount along with the direction of abutment tooth displacements were studied.
The results were as follows;
1. Three dimentional displacement was observed immediately after the loss of occlusal and proximal contacts, and the amount of displacement kept increasing along with time.
2. The abutment tooth displaced towards the distal, coronal and lingual direction.
3. Compared to the buccolingual and axial directions, the mesiodistal direction showed the greatest amount of abutment tooth displacement, with the maximum displacement being 240μm.
View full abstract
