Although numerous reports have dealt with the detection of Candida in the oral cavity of adults, few have investigated the presence of Candida in children. Candida albicans is thought to be the pathogenic bacteria for oral candidiasis, particularly in children. Oral candidiasis may appear in healthy children when a general drop in resistance is experienced. This report examined the presence of Candida in the oral cavity of children between 3-and 15-years-old (55 boys ; 45 girls). The following results were obtained :
1. The greatest concentration of Candida was found at the dorsum of the tongue.
2. The presence of Candida alone was difficult to determine using Stomasta^®.
3. The incidence of Candida was closely related to changes in the oral environmental caused by factors such as eruption of permanent teeth, unstable occlusion, and inadequate oral hygiene.
4. The data suggested some kind of relationship between increases in Candida and gingivitis.
5. Even with the placement of intraoral retainers, increases in Candida could be suppressed by properly cleaning the retainer and maintaining the oral environment in healthy condition.

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Blood is currently used as the specimen for hepatitis antibody tests, but because of the risk of infection, e.g., by needle prick accidents, etc., and the need to secure technicians to collect the blood, etc., the use of blood specimens could hardly be said to necessarily be the best method. In this study we collected oral fluid from patients with hepatitis B and C by means of an OraSure simple oral fluid collection device and measured hepatitis antibodies in oral fluid with a serum hepatitis antibody kit. The following four basic tests were performed in the oral fluid experiment : 1. within-run reproducibility tests, 2. dilution tests, 3. freeze-thawing tests, and 4. storage stability tests, and the results were compared with the findings in a blood specimen drawn from the same subject. The values obtained in the basic investigation consisting of the within-run reproducibility tests, dilution tests, freeze-thawing tests, and storage stability tests were within the precision limits, and no changes in the results of the evaluations were observed. Comparison of the results of measurements in oral fluid with the results in serum showed that oral fluid was positive in 6 of the 7 patients who were seropositive for hepatitis B, a sensitivity of 86%, and since all of the 16 patients who were seropositive were also oral-fluid-positive, specificity was 100%. Similarly, in hepatitis C sensitivity was 88% and specificity was 100%.

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Hydroxyapatite (HA) are received strong interests in implant surgery because of their high osteoconductivity and promotion the early fixation to bone. However, since the strength of HA is insufficient, composition between metallic materials and HA have been examined. We already reported that thin crystalline HA coating could be formed on an even titanium plate by a discharging method in Hanks' balanced salt solution without organic molecules. In this study, we examined the availability of this method on titanium plate prepared by wire-type electric discharge machining (wire-EDM) having a characteristic irregularly surface. Results showed that thin crystalline HA coating can be prepared on the wire-EDM surface for 900 s processing.
According to this study, we assumed that this method is suitable to prepare HA coating on the current titanium implants having various irregularly shapes such as the wire-EDM.

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The purpose of this study was to evaluate the characteristics of the newly developed resin composite (DRC) for denture border extension and/or repair. The filler structure was evaluated by weight contents, observation in morphology under a back-scattered electron (BSE) image, and element analysis by EPMA. The bending properties were compared with those of three kinds of commercial denture-repair resin products before and after the thermal cycle (5-60°C/minute, 5,000 times). DRC was constructed from two kinds of pastes with dual curing (chemical and light curing). DRC consisted of round-shaped organic filler, matrix resin, and micro-inorganic filler with a content of approximately 15 wt%. The DRC showed the highest deflection, and lower bending strength under a bending test. Moreover, the bending properties of DRC suffered less deterioration after thermal cycling. DRC had a capacity of larger deformation despite the composite material and had higher resistance for fracture because of the distribution of spherical organic fillers. Therefore we suggested that DRC was useful material for denture border extension and repair with adequate elasticity and easy manipulation.

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Recently, composite resins for facing crowns have been widely used for natural colored prosthetic materials. However, over time the colors of these materials undergo changes. Therefore, color changes of 6 kinds of composites, which were immersed in filtered coffee for 4 weeks, were examined in this study. The results of the experiment indicate that all the composites showed visible color changes after one week of immersion in coffee. Moreover, enamel paste showed poorer color stability than dentin paste. Similarly, non-polished surfaces were more discolored than polished surfaces.

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This report presents the results of a long-term orthodontic care of an individual with unilateral cleft lip and palate with prosthetics oral rehabilitation for the alveolar cleft.
The case of this report was a young female with unilateral cleft lip and palate who had congenital absence of 2. She had her first orthodontic examination at the age of seven. She had an operation on her lip at 4 months and on her palate at 1 year 4 months after birth. The first stage of the orthodontic care of lateral expansion and maxillary protraction was started at the age of nine. Bone grafting at the alveolar cleft had not been carried out.
After growth observation for some years, a multibracket system was used at the second stage of orthodontic care from the age of 14 years and 6 months to the age of 18 years. Prosthetics rehabilitation was performed and it had been passed more than 3 years after debonding. The occlusion was found to have stabilized.

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In order to clarify the remaining problems to be solved in clinical orthodontics, we evaluate the diagnosis and treatment procedures in intractable cases which required over 5 years of active treatment period. In this article, four surgical-orthodontic cases were introduced.
With doctor's opinion about his treatment, retrospective considerations were discussed.
Most serious problem was the luck of scientific way for evaluation of interrelationship among Function-Occlusion-Skeleton. Causing this point, unpredictable results were observed during treatment. Orthodontists could not find the effective and speedy way for reconstruction of new occlusion in new skeletal condition. Next was the limitation of vital information in individual patient such as location of cortical bone and root surface. The necessity of utilization of genetic analysis in orthodontic diagnosis was also recognized.
From the critical and scientific conscience, real target in treatment and practical aim of clinical research were enumerated as follows :
1. Development of new image analysis with quantitative and three-dimensional evaluation.
2. Development of individual and patient-specific biomechanical simulations.
3. Development of diagnosis technique employing genetic analysis.

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In the case of the maxillary and mandibular jaws deformity is corrected by surgery, it is considered that the stomatognatic function is changed and the masticatory muscle is effected by the correction of the deformity. Therefore, for getting stability of occlusion, it is important to examine the functional effect on masticatory muscle before and after surgery. As the stability of occlusion and adaptation of muscle function after treatments are closely related, functional assessments before and after the treatments are important when the treatments entail such drastic changes.
In this paper, a clinical trial case is presented that vertical height collapse and mandibular deformity.
In order to examine the functional effect on masticatory muscles by surgical orthodontic treatment, electromyographic (EMG) signals were obtained using bipolar surface electrodes. The muscle activity was recorded from the bilateral masseter muscles, anterior border of temporal muscles and posterior border of temporal muscles during isometric contraction by maximum clench in intercuspal position initial, before surgery (with or without temporary denture), one month, three, six, eight, twelve months after surgery.
1. For the reconstruction of the occlusion, the harmony of muscle balance of right and left was established using the electromyogram. As the result, there was no the clinical manifestation which changed to the problem from the pre-surgical orthodontics over the post-surgical orthodontics.
2. The EMG biofeedback was done to this patient using the EMG waveform. As the result, the stability of the postoperative mandibular position was good, and because that it controls right and left mastication muscles balance by using EMG biofeedback.
From these results, the EMG analysis seemed to become not only functional analysis of surgical orthodontic therapy but also effective method for myofunctional therapy to the postoperative stability.

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This study was carried out to determine statistical information concerning the crowns and the fixed partial dentures (total number, type and rate of crowns, number of vital or non-vital abutment teeth, etc.) which were placed in the outpatients in the Department of Fixed Prosthodontics at Showa University Dental Hospital from April 2000 to March 2001.
The following results were obtained :
(1) The total number of crowns and fixed partial dentures produced were 1033; among them, crowns totaled 826 (80.0%) and fixed partial dentures, 207 (20.0%).
(2) Most of the crowns were full cast crowns (398, 48.2%); the second most commonly produced was resin-faced cast crowns (190, 23.0%); the third was porcelain-fused-to-metal crowns (187, 22.6%).
(3) Resin-faced cast crowns and porcelain-fused-to-metal crowns were most commonly used for the anterior teeth; full cast crowns and porcelain-fused-to-metal crowns, for the premolar teeth; full cast crowns, for the molar teeth.
(4) Fixed partial dentures located in the posterior region were 58.5%; the antero-posterior region were 21.2%; the anterior region were 20.3%.
(5) With regard to the relationship between the missing teeth and the abutment teeth of the fixed partial denture, three-unit fixed partial dentures (one missing tooth with two abutment teeth) were most frequently treated in all regions.
(6) The crowns covered by the insurance dental service were 71.1%; the fixed partial dentures were 64.3%.
(7) Concerning the abutment teeth of the crowns, non-vital teeth were 84.5%, implant abutments were 5.0%; non-vital teeth of the fixed partial dentures were 69.65%; implant abutments were 0.4%.

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