Purpose: With an increase in the aged population in Japan, it is important that clinicians evaluate the outcome of complete denture treatment based on evaluation by dentists and patients to provide high-quality treatment. The purpose of this study was to evaluate the evaluation and to clarify the relationship between them by dentists and patients.
Methods: Forty patients wearing complete dentures were selected, after obtaining informed consent. Scores of complete denture, supporting tissue, chewing function, satisfaction and QOL were the factors used for evaluation. These were evaluated at four stages in complete denture treatment: at the initial visit, before insertion of new dentures (just before), first visit after insertion of new dentures (1st visit) and 1 month after insertion. We compared scores obtained just before and at the 1st visit using t-test, and analyzed changes in scores with correlation coefficient. In addition, the relationship between dentists and patients was analyzed with kappa statistic.
Results: Evaluation of the new denture was influenced by the evaluation of the old denture. In case of high evaluation of old dentures, evaluation of new dentures tended to decrease. Conversely, in case of low evaluation of the old dentures, evaluation of new dentures tended to increase (p < 0.01). There was no significant correlation between the evaluation by the dentists and the patients.
Conclusions: Changes after wearing new dentures and the relationships were clarified. The disagreement of the evaluation by dentists and patients suggests that both evaluations should be done comprehensively.

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Purpose: To establish standardized evaluating methods for jaw movements analysis independently of the reference coordinate system. In this paper, we focused on the analysis of incisor point paths of border movements. Then we investigated parameters that are independent of the reference coordinate system and can be utilized among different systems.
Methods: Recorded data of jaw border movements from 20 healthy male adults were employed as basic samples. First, the effects of changes of the reference coordinate systems on the analysis were investigated. Second, the line between incisor points at the intercuspal position and the maximal mandibular opening position was used as the reference line. Then the area index of incisor paths was calculated with the length of the perpendicular line dropped from the incisor point to the reference line and the displacement of the foot of the perpendicular.
Results: Changes of the spatial relation between a reference plane of the coordinate system and border movements pathways had an effect on a measured area of projected pathways, about 2%-5% differences of projected area on the frontal plane with 10 degrees rotation around a horizontal axis. The area index of incisor paths showed close correlation with the actual area of a 3-dimensional plane bounded by the incisor path [sagittal border movement: ρ = 0.53 (p = 0.016), left border opening pathway: ρ = 0.97 (p < 0.001), right border opening pathway: ρ = 0.98 (p < 0.001), Spearman rank correlation].
Conclusion: The results suggest that new parameters could measure jaw border movements quantitatively independent of the reference coordinate system.

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Purpose: To establish standardized evaluating methods for jaw movements analysis. In this paper, we investigated evaluating parameters for 6 degree-of-freedom jaw movements data.
Methods: Recorded data of jaw border movements from 20 male adults were employed as basic samples. The main parameters were as follows: 1. The displacement of an intercondylar midpoint: the length of a straight line between 2 positions of this point, the intercuspal position and other jaw position. 2. The angle of intercondylar axes: the angle between 2 position of the intercondylar axis, the intercuspal position and other jaw position. 3. The angle of incisal-condylar planes: the angle between 2 position of the plane, the intercuspal position and other jaw position (this plane was defined with the incisal point and condylar points of both sides 4. The mandibular motion range index: quantitative values calculated with 2 of 3 parameters described above.
Results: The mandibular motion range index showed a close correlation with respective projected areas of the incisal paths, with the projected area of sagittal border movements on the sagittal plane ρ = 0.82 (p < 0.001), with the projected area of lateral border movements on the frontal plane: left lateral border movements ρ = 0.92 (p < 0.001), right lateral border movements ρ = 0.84 (p < 0.001), Spearman rank correlation.
Conclusion: New parameters were based on 6-degree-of-freedom jaw movements data and relative relationship between the intercuspal position and other jaw position. They were independent of reference coordinate systems and could measure jaw movement quantitatively.

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Purpose: The effects of bleaching times, types of etching agent and storage period of bleached bovine tooth on the shear bond strength of resin cement to the enamel were examined.
Materials and Methods: Bovine teeth were repeatedly bleached 0, 1, 3, and 5 times then stored in 37°C water for 1 week. The effect of bleaching number of the bovine tooth on the bond strength of resin cement to the enamel was investigated using 40% phosphoric acid (EG) etching technique. Next, the effects of types of etching agent and of storage period of bleached bovine tooth with three times in 37°C water on the bond strength were studied using 10% citric acid-3% ferric chloride (10-3) or 10% citric acid (10-0) solution.
Results: The bleaching of bovine tooth allowed for a dramatic decrease in the bond strength from 18.3 MPa to 9.8 MPa (1 time), and 3.9 MPa (3 times), even though the bovine enamel was etched by EG. However, when 10-3 or 10-0 solution was applied to the three times bleached enamel, bond strengths were 13.9 and 10.0 MPa, respectively. Furthermore, prolonging of the storage period of the three times bleached bovine tooth in water to 2 months resulted in a increase in the bond strength from 3.9 to 10.1 MPa, even if bovine enamel was etched by EG, and close to that obtained from the 10-3 etching.
Conclusion: To obtain the expected bond strength to bleached enamel, it is better to wait for 2 months for a restoration and use the 10-3 etching.

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Purpose: Clinical findings were compared with glucose, protein, albumin, bilirubin, creatinine, pH, occult blood, ketone body, nitrite, and white blood cells contained in whole saliva to investigate the components that most markedly reflect the periodontal condition.
Material and Method: The subjects were staff of the Prosthodontics Department, Showa University, and patients who visited for dental treatments (57 subjects in total). At the first time, saliva samples were gargled with 1.5 ml of distilled water for 15 seconds and collected by spitting out into a paper cup. At the second time, saliva samples were collected by the same method. At the third time, saliva samples after chewing paraffin gum for 60 seconds were collected by spitting out into a paper cup. Thus whole saliva collecting that was divided on three times. After sampling, 8 μl of the saliva sample was dripped in reagent sticks for the 10 items of urinary test paper and the reflectance was measured using a specific reflectometer. In the periodontal tissue evaluation, the degree of alveolar bone resorption, probing value, and tooth mobility and the presence or absence of lesions in the root furcation were examined and classified into 4 ranks. The mean values in each periodontal disease rank and correlation between the periodontal disease ranks and the components were statistically analyzed.
Results: Bilirubin and ketone body were not measurable. The components density of the 8 items was increased as the periodontal disease rank increased. Regarding the correlation between the periodontal disease ranks and the components, high correlations were noted for protein, albumin, creatinine, pH, and white blood cells.
Conclusion: The simultaneous measurement method of 8 salivary components using test paper may be very useful for the diagnosis of periodontal disease of abutment teeth.

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Purpose: For diagnoses of temporomandibular dysfunction, reports indicate the importance of analyzing jaw movements using a jaw motion tracking device with six degrees of freedom. However, such devices are not widely applied in clinical practice, due to difficulty of use. To determine whether CMS-JAW (a newly developed six degrees of freedom jaw motion tracking device that features easy analysis of jaw movements) offers the measurement accuracy required for clinical use, we evaluated the device by measuring condyle translation and rotation during jaw movement.
Methods: In this study, we evaluated measurement accuracy by comparing measurements of condyle movements obtained from the Win Jaw System, a comparable jaw motion tracking device with six degrees of freedom based on an ultrasonic recording system; the Gnathohexagraph II, a device based on a different measurement principle; and the CMS-JAW. In the experiment, we confirmed the condyle translations and rotations obtained by each device by measuring distances and angles, respectively, with a micro slider for three-dimensional measurements (to an accuracy of 0.01 mm and 0.02 mm) and a digital protractor (to an accuracy of 0.1 degrees).
Results: No significant distortions were observed in the space replicated based on the range of condyle translations obtained with CMS-JAW. Deviations from theoretical values were greatest along the z-axis, with a maximum error of 0.20 mm and root mean square (RMS) error of 0.10 mm. The maximum error for angles of condyle rotation was 0.50 degrees; RMS errors ranged from 0.05 to 0.30 degrees.
Conclusion: Our analysis of condyle movement demonstrates that the CMS-JAW provides acceptable measurement accuracy for clinical applications.

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Purpose: To validate whether the data for individual patients are correctly reproduced in sagittal condylar path inclination of the articulator, the data obtained by the conventional anterior check bite method and the data obtained by a jaw-tracking system with six degrees of freedom were compared.
Methods: In 5 subjects (4 males and 1 female) with healthy tooth alignments, 5 anterior check bites were obtained from each subject. Sagittal condylar path inclination was measured using seven types of semi-adjustable articulator. Next, the anterior gliding movement was measured 5 times in all 5 subjects using a jaw-tracking system with six degrees of freedom (MM-JI-E, Shofu Inc. Kyoto, Japan. The sagittal condylar path inclination data obtained with semi-adjustable articulators were compared to those obtained by the jaw-tracking system using the two-way analysis of variance and Fisher's PLSD method (α=0.05).
Results: In measurements of the same subjects for five types of articulators with the check bite method, significant differences were observed by two-way analysis of variance, and differences in measurements among articulators were found (p<0.01).
Regarding the sagittal condylar path inclinations measured with Hanau-184 Wide-View and Dentatus ARL articulators, significant differences were observed on both right and left sides compared with the jaw-tracking system. With the Denar Centri-Check System and Denar Mark II, significant differences were observed on one side (p<0.05).
Conclusion: Denar Cadiax Compact, Hanau Condyle Repositioner, and Hanau H2O are recommended for more accurate measurements of the sagittal condylar path inclination.

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Purpose: Bone marrow stromal cells (BMSCs) are a promising cell source in applications for tissue engineering and regenerative medicine. Optimization and control of the growth and differentiation of cultivated cells can be achieved by the administration of growth factors and hormones in vitro. This study provided experimental information on the enhancement of the osteogenic potential of rat BMSCs in vitro and in vivo.
Methods: Mineralized nodule formation of rat BMSCs in culture for 3 weeks with dexamethasone (Dex)-treated media supplemented with both basic fibroblast growth factor (bFGF) and 17β-estradiol (E2) was examined by histology. In porous β-tricalcium phosphate (β-TCP), proliferation, migration, and differentiation of BMSCs were examined by histology and transmission electron microscopy. After culturing, the composites were subcutaneously implanted into syngeneic rats. The tissues with implants were harvested after 4 weeks and evaluated microscopically by using histological stain.
Results: Dex-treated media supplemented with both bFGF and E2 was the most effective in mineralized nodule formation of BMSCs in vitro. Light and electron microscopy revealed the presence of many cells with developed rough endoplasmic reticulum. Bone formation in the BMSC/β-TCP composites in cultures in vitro for 3 weeks was observed histologically at 4 weeks after implantation. When BMSC/β-TCP composites were cultured in Dex-treated media supplemented with both bFGF and E2, the amount of bone formation at implants was substantially greater than that of composites cultured in Dex-treated media supplemented with bFGF.
Conclusion: The combined use of bFGF and E2 could effectively improve the bone-forming ability of BMSCs.

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Purpose: To evaluate the causes of temporomandibular disorder (TMD) by examining the relationships between 3 major TMD symptoms, parafunction, and stress, a questionnaire survey was performed during dental examinations in corporations.
Methods: The survey was performed using 6 questions on the following topics: 1. Trismus; 2. Joint noise; 3. Pain; 4. Clenching in the daytime; 5. Nocturnal bruxism; and 6. Stress.
There were 3,225 subjects, 2,809 males and 416 females and the mean age of the subjects was 40.12 years. The relationships between questions 1 to 5 and question 6 were examined by the chi-square test.
Results: There were significant correlations (question 1, p=0.001; questions 2-5, p<0.001).
Conclusion: Clearly, there was an influence of psychological factors, such as stress, on TMD, and such factors were considered to play important roles in its etiology, progression, and treatment. The results of this study suggest that well-controlled studies of TMD are necessary.

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Purpose: We previously reported correlations between the pressure pain threshold (PPT) at the styloid process, which represents individual pain sensitivity, and PPTs of the masticatory muscles in healthy subjects, and proposed the 95% confidence interval (95%CI) of the PPT at the styloid process as a reference range. In this study, we evaluated its usefulness as a reference range.
Methods: Serial changes in the PPT relative to the 95%CI were studied in 7 healthy subjects. Next, the determination of abnormal sites in the PPT relative to the 95%CI was studied in 7 patients with temporomandibular disorders (TMD).
Results: In the healthy subjects, the PPT remained within the 95%CI at all sites. Since the PPT deviated from the 95%CI at some sites in TMD patients, abnormal sites could be determined.
Conclusion: The 95%CI of the PPT at the styloid process is useful as a means for the evaluation of muscle symptoms of TMD patients.

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Patient: A 70-year-old patient with reconstructed mandibulectomy presented to our clinic with a complaint of denture instability. Due to left mandibular gingival cancer, she had received segmental resection of the left mandible and reconstruction with the fibula. An intraoral examination revealed few intermaxillary occlusal contacts due to the deviation of the mandibular dental arch. A mandibular denture and maxillary prosthesis with palatal ramp were fabricated to provide sufficient occlusal contacts and bilateral balanced occlusion.
Discussion: Regardless of reconstruction, a careful case history, combined with meticulous clinical evaluation was demanded in this mandibulectomy patient. The ramp on maxillary prosthesis could provide not only proper occlusal scheme but also stability of mandibular denture.
Conclusion: To improve masticatory function in a reconstructed mandibulectomy patient with deviated mandibular movement and disagreement of occlusion, maxillary prosthesis with palatal ramp was effective.

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Patient: A 20-year-old female patient with lower anterior teeth defect was referred from the Department of Oral and Maxillofacial Surgery and Orthodontics, Tokushima University Dental Hospital. The patient had severe resorption of alveolar bone around lower anterior edentulous and was treated with Brånemark implant system.
Discussion: The implant prosthesis made fine outcome and was satisfactory for the functional and esthetic requirement of the patient. The superstructure, which was constructed with a combination of inner and outer crowns, resulted in over counter design. Maintenance of the implant and dental hygiene was continued with the cooperation of the Department of Preventive Dentistry.
Conclusion: The dental implant prosthesis could satisfy the functional and esthetic expectations of this patient sufficiently.

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Patient: A 70-year-old woman presented with a complaint of masticatory pain and disturbance. She had collapse of occlusal support and vertical dimension decrease. This case used provisional restoration for increasing vertical dimension and reconstruction of anterior guidance. After confirming occlusal stability, she was treated with fixed prosthesis and removable partial dentures.
Discussion: This patient was followed for 6 and a half years with no prosthetic complications, because the reconstruction of bilateral occlusal support and anterior guidance were performed.
Conclusion: It is important to reconstruct the occlusal support and anterior guidance in cases of prosthetic treatment of occlusal collapse.

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Patient: The patient's chief complaint was difficulty of mastication in molar regions. The diagnosis was masticatory dysfunction caused by loss of occlusal contacts. Initially provisional restorations were fabricated, then disharmonious contours were corrected during the following treatments including endodontic and periodontic treatments and tooth extraction. Final restorations were made with fixed partial dentures.
Discussion: Preservation of the left incisor of mandible enabled recontouring the provisional restoration and consequently, determining a definitive occlusal scheme for the final restoration.
Conclusion: For a patient with collapse of posterior occlusal contacts, hopeless teeth which should be extracted were used as temporary abutment for the provisional restoration. This treatment plan minimized trouble for the patient during treatment, resulting in successful final occlusal reconstruction.

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Patient: A 62-year-old man complained of discomfort during insertion of lower removable partial denture (RPD). Existing denture was highly objectionable to tongue and intolerable to wear due to volume and contour of its lingual aspect. The treatment plan included fabrication of an interim denture and altering its shape until it did not lead to discomfort, followed by fabrication of a final denture. Consequently, RPD using sublingual bar was found to be the most comfortable to wear and was fabricated as final denture. The patient was ready to insert the final denture and restoration of masticatory function was accomplished.
Discussion: In cases with unfavorable anatomic conditions such as a lack of mouth-floor depth, lingual plate should be applied as first choice, and when it is not well tolerated by the patient, sublingual bar should be applied.
Conclusion: Sublingual bar is suggested to be one of the least objectionable major connectors.

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Patient: A 39-year-old female patient was admitted with mobility of maxillary anterior fixed partial denture. She was diagnosed as severe chronic periodontitis of abutment teeth of the denture, left alveolus cleft, and anterior/posterior crossbites. The crossbites were improved by prosthetic approach using an implant-supported fixed partial denture with a removable gingival veneer at the anterior and crowns at the posterior. The implant-supported fixed partial denture and most teeth have been kept in a stable condition.
Discussion: Sufficient lip support and proper phonetic function were recovered by implant-supported fixed partial denture with removable gingival veneer. The long-term stability of implants may be due to easiness of toothbrushing and connection of implants rendered by the fixed prosthesis.
Conclusion: This case suggests that implant-supported fixed partial denture with removable gingival veneer could be useful for severe ridge resorption.

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Patient: A 70-year-old woman visited our clinic with a chief complaint of chewing difficulty due to serious periodontitis and an improper RPD. A poor prognosis of the maxillary anterior residual teeth was predicted. However, the patient's consent for tooth extraction could not be obtained. Consequently, the RPD was designed for the future additional tooth.
Discussion: The maxillary RPD has been functioning for 9 years through repeated additional teeth and repairs. Designing of the metal plate for the predicted prognosis allowed for additional teeth and repairs after losing of the residual teeth.
Conclusion: Designing of the denture for the predicted prognosis allowed long-term continuous use of the denture.

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Patient: The patient was a 72-year-old woman who presented with chief complaints of masticatory and esthetic impairment due to detachment of a bridge in the anterior tooth region. These symptoms were attributed to displacement of the mandibular position caused by an untreated defect in the mandibular molar region and extrusion of the mandibular anterior tooth region associated with reductions in the occlusal vertical dimension of the molar region. The occlusal vertical dimension was restored using a denture with an occlusal splint as treatment denture, and functional and esthetic recovery was observed.
Discussion: Establishment of stable occlusal support in the molar region is thought to be utmost importance in stabilizing prosthesis of the anterior tooth region.
Conclusion: Although a unilateral defect was observed in the mandibular molar region, use of a denture with an occlusal splint enabled bilateral elevation in addition to creation of denture space in the maxilla. The occlusal splint region was then replaced with prosthesis to obtain a stable occlusal relationship in the molar region and simultaneously to facilitate functional and esthetic recovery of the anterior tooth region.

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