Biomedical subjects

Kanji Ishibashi

Publications and source records attributed to Kanji Ishibashi.

5 recordsLinked to original sources

PubMed2006

[Functional recovery with prosthetic management for segmental resection of the mandible without reconstruction].

PATIENT: The patient, a 54-year-old male, consulted the Oral Surgery Department of Iwate Medical University Hospital with a complaint of a mass in the left oral base in June 1992. In September 1992, the patient was diagnosed as having cancer in the left mandibular base, and the tumor was excised by resection of the entire cervical region on the left side. Since radiation osteonecrosis in the left mandible and mandibular fracture were detected, segmental excision of the left mandible was performed in March 1993. Although the postoperative course was good without reconstruction, the patient consulted the Second Prosthetic Department to achieve functional recovery in February 1996. This patient had no occlusal contact between the maxilla and mandible because the mandible shifted to the affected side. After fixation of a mandibular prosthetic appliance for the defective mandible, a palatal plate for the maxilla in occlusal contact with the mandibular dentition and mandibular prosthetic appliance were fixed in November 1997. After fixation of a new mandibular prosthetic appliance and dentures for the maxilla with palatal ramp in April 2001, masticatory function was observed to have improved with control of the mandible. DISCUSSION: To prevent the mandibular shift and improvement of the masticatory function, a palatal plate with a palatal ramp in the occlusal contact region was fixed, and a balance of the masticatory muscles could be maintained. An evaluation of the level of improvement in the masticatory function and the pronunciation function indicated that the mandibular prosthetic appliance and palatal plate with a palatal ramp in the occlusal contact region increased the kind of food that the patient could take. Moreover, by enlarging the narrow Donders space, the pronunciation was improved. CONCLUSIONS: Fixation of a palatal plate with a palatal ramp in the occlusal contact region without reconstruction of the mandibular bone was useful for the control of mandibular deviation to the affected side and improvement of the masticatory function.

Dental Prosthesis↗

PubMed2005

Reproducibility of tooth color gradation using a computer color-matching technique applied to ceramic restorations.

STATEMENT OF PROBLEM: To reproduce tooth color precisely, an objective methodology based on color science is required. However, perception-based techniques are still the primary method for color matching in restorative dentistry. PURPOSE: This study evaluated the accuracy of reproduction of color gradation for ceramic restorations using a Computer Color Matching (CCM) technique employing a prototype program and spectrophotometric data measurements. MATERIALS AND METHODS: The colors of 10 target-shade tabs of the Vitapan 3D Master shade guide were measured at 4 regions of crowns from the cervical to the incisal area using a spectrophotometer. Tooth-shaped CCM ceramic specimens (30 specimens; 3 specimens for each of 10 target-shade tabs), the same size and shape as target-shade tabs, were fabricated according to the CCM prescriptions calculated using a prototype CCM program. The colors of CCM ceramic specimens and target-shade tabs were compared in 10 incremental areas from gingival to incisal (each measuring 1 mm high x 3 mm wide). The color differences, Delta E, Delta L* , Delta a* , and Delta b* , were calculated. The color difference Delta E values were analyzed by a repeated measures analysis of variance (P <.0001). Three prosthodontists evaluated CCM specimens by perception techniques. RESULTS: The mean color difference (Delta E) values were clinically acceptable (below 3.6) for incremental areas 3 through 10 and unacceptable for areas 1 and 2 (gingival area). Highly significant differences in the mean of Delta E values among target-shade tabs (P <.0001), areas (P <.0001), and target-shade tab-by-area interaction effects (P <.0001) were noted. However, perceptional evaluation indicated "Definitive match" or "Approximate match" for all CCM specimens. CONCLUSION: The CCM technique tested in this study utilizing 4 measurements on target-shade tabs could reproduce tooth color gradation from incisal to precervical regions with clinically acceptable results.

Analysis of Variance↗

PubMed2005

[A case report of treatment for complex dysfunction of occlusion and mastication due to a maxillary fracture].

PATIENT: A case report of a 39-year-old man complaining of complex dysfunction of occlusion and mastication is presented. The patient came to Iwate Medical University Hospital following urgent hospitalization and treatment at a local hospital after catching his head in a forklift. The patient consulted the Second Prosthetic Department with the purpose of occlusal examination in April, 1994 and he was diagnosed with a malunited maxillary fracture. Afterwards, surgical correction was performed, but complex dysfunction of occlusion and mastication remained. Fixed prosthesis treatment was then planned and a dental prosthesis was set in April, 2000. His prognosis has since remained favorable. DISCUSSION: At the commencement of treatment, both surgery and orthodontic treatment were considered, but the patient desired early social rehabilitation. Therefore, a dental prosthesis was used to restore facial asymmetry and mandibular function. CONCLUSIONS: Rehabilitation of occlusal function was achieved by using a dental prosthesis. This facilitated early social rehabilitation and helped improve the patient's quality of life. Since there have been few reports of cases in which a dental prosthesis was used to correct occlusal disharmony after surgical correction due to maxillary fracture, long-term follow-up will be needed for this patient in order to increase knowledge about treatment strategies for such cases.

Adult↗

PubMed2004

A procedure for fitting a fixed partial denture to an existing removable partial denture.

An indirect technique for fitting a new cast gold crown or fixed partial denture (FPD) to an existing removable partial denture (RPD) is presented. This method uses an acrylic resin coping made on a definitive cast fit directly to the patient's RPD intraorally, with the new FPD subsequently completed on the cast. The patient does not have to relinquish the RPD for laboratory procedures, although an appointment is required to fit the coping intraorally where contact is made with the RPD.

Crowns↗

PubMed2004

Comparison of effectiveness of two 10% carbamide peroxide tooth-bleaching systems using spectrophotometric measurements.

PURPOSE: The purpose of this study was to compare the color changes achieved with two commonly used bleaching systems on the basis of a spectrophotometric analysis. MATERIALS AND METHODS: Two commercially available 10% carbamide peroxide bleaching systems were used by a total of 48 individuals. Subjects who had intact natural maxillary anterior teeth void of any restorations or decay that had not been subjected to any prior bleaching were included. Opalescence 10% PF (Ultradent Products Inc., South Jordan, UT, USA) was used by 23 patients for 14 days, whereas Nite White Excel (Discus Dental, Culver City, CA, USA) was applied by 25 patients for the same duration. Tooth colors for the middle one-third region of maxillary central incisors and canines were measured with a spectrophotometer prior to bleaching and after 14 days of bleaching. Color difference deltaE and color coordinates L* (lightness), a* (redness), and b* (yellowness) of CIELAB color system (developed by the Commission Internationale de l'Eclairage) were calculated. RESULTS: Mean deltaE values for Opalescence ranged from 5.03 to 8.92 and from 5.84 to 9.61 for Nite White. The most significant factor of the color change was b* followed by L* and a*. L* values were higher after bleaching, whereas values for both a* and b* decreased. There were no significant differences between the two systems examined (p < .05).

Adult↗