Yuji Shiratsuchi

Immunohistochemical evaluation of PCNA and Ki-67 in ameloblastoma

Thirty-two ameloblastoma tissues were immunohistochemically studied using monoclonal anti-proliferating cell nuclear antigen (PCNA) and anti-Ki-67 antibodies. Positive cells were evaluated and analyzed in relation to the WHO classification, cytological pattern of the outer layer cell, clinical appearance, tumor location, radiographic appearance and patients age. In regard to the cytological pattern of the outer layer cells, the basal cell type had significantly higher PCNA and Ki-67 (P<0.05) labeling indices than the cuboidal cell type. The solid type had significantly higher PCNA and Ki-67 (P<0.05) labeling indices than the cystic and the mixed type. The labeling index of the younger patient was found to be the lowest, the middle age was in the middle and the older patient was the highest. These results indicated that the proliferating activities of ameloblastomas are quite variable, and the evaluations of Ki-67 and PCNA seem to be good indicators to assess the proliferating activity of each type of ameloblastomas.

Evaluation of masticatory function following orthognathic surgical correction of mandibular prognathism

Masticatory function was examined in 17 patients with mandibular prognathism before and after bilateral sagittal splitting osteotomy of the mandibular rami. Masticatory efficiency was measured by means of a spectrophotometer, using adenosine triphosphate (ATP) granules, the biting force and occlusal contact area. Masticatory functions showed a tendency to gradual improvement postoperatively. Concerning masticatory efficiency, mean values of absorbance of ATP granules in patients with mandibular prognathism were inferior to those of subjects who possess a normal occlusion, even 12 months after operation.

Two relatively distinct patterns of ameloblastoma: an anti‐apoptotic proliferating site in the outer layer (periphery) and a pro‐apoptotic differentiating site in the inner layer (centre)

Two relatively distinct patterns of ameloblastoma: an anti‐apoptotic proliferating site in the outer layer (periphery) and a pro‐apoptotic differentiating site in the inner layer (centre)

Hard and soft tissue stability of orthognathic surgery.

OBJECTIVE To test the hypothesis that there is no difference in the stability of the hard and soft tissue changes following a surgical mandibular setback using a sagittal split ramus osteotomy or an intraoral vertical ramus osteotomy. MATERIALS AND METHODS The samples consisted of 45 female patients with mandibular prognathism, who were divided into two groups. Twenty-three underwent a sagittal split ramus osteotomy (SSRO) with rigid fixation by titanium mini-screws and maxillomandibular fixation (MMF) for 14.0 +/- 0.7 days. Twenty-two underwent intraoral vertical ramus osteotomy (IVRO) without rigid fixation, and MMF was released 21.5 +/- 3.3 days after surgery. Data were collected from standardized cephalometric radiographs taken at the start of preoperative orthodontic treatment (T1), immediately after surgery (MMF, T2), and the completion of postoperative treatment (T3). Angular measurements were compared on each of T1, T2, and T3. RESULTS There were no significant differences in the pretreatment hard and soft tissue morphology between the SSRO and IVRO. However, when fixation was released, the mandible was posteriorly positioned in the IVRO group. In the soft tissue profile, the mental region was located backward in the IVRO group at postoperative stage (T3). CONCLUSIONS The hypothesis is rejected. The soft tissue profile of the IVRO group especially showed a retromandibular position after postoperative treatment in comparison with the SSRO group. This tendency of the IVRO group would contribute to the database for treatment planning and prediction.

Familial occurrence of oral cancer: Report of cases

Four cases of familial occurrence of oral cancer are described and the postulated causes and predisposing factors of oral cancer are reviewed. None of these factors could satisfactorily explain the unusual familial occurrence observed in the cases presented.

Posterior lingual mandibular bone depression

An unusual case of posterior lingual mandibular bone depression in a 39-year-old Japanese man is reported. The bilocular type of this condition was composed of 2 large ovoid radiolucent areas which were adjacent to each other. The diagnosis of this condition was made by sialography and tomography. The present case was compared with other unusual cases reported in the Japanese literature.

Orthognathic Treatment with Autotransplantation of Impacted Maxillary Third Molar

This article presents orthognathic treatment in successful collaboration with autotransplantation of the maxillary third molar. The case report describes a 24-year-old man with severe mandibular protrusion and severe crowding in both dentitions. Overbite was 0 mm, overjet, -15 mm. Maxillary second molars and mandibular third molars were extracted, and presurgical multibracket treatment was begun. Maxillary third molars were impacted completely at 18 months in terms of presurgical tooth alignment. Autotransplantation of the teeth was achieved to substitute for extracted maxillary second molars. At 6 months after autotransplantation, the maxilla was advanced 4 mm on both sides through a Le Fort I procedure; left and right sides of the mandible were set back 15 and 18 mm, respectively, via sagittal split ramus osteotomy to improve mandibular protrusion. The total treatment period lasted 37 months. Autotransplantation treatment is an effective modality for tooth replacement when a donor tooth is available. Fully impacted maxillary third molars are potentially reliable candidates for autotransplantation.

Multiple endocrine neoplasia type 3: Three cases with mucosal neuromata

Three female patients (ages 10, 18 & 25 years) with multiple endocrine neoplasia type 3 are reported. They had all characteristic facial appearances, with mucosal neuromata, rubbery swollen lips, tubercles on the tongue and eversion of the eye lids. Clinical signs and symptoms appeared to be progressive with increase in age, suggesting the importance of the correct diagnosis and early evaluation of endocrine function leading to a better prognosis for the patient.

Mandibular ameloblastoma associated with salivary gland tumor

2 cases of mandibular ameloblastoma associated with salivary gland tumor are presented. Case no. 1, a 32-year-old male was diagnosed as mandibular ameloblastoma and acinic cell tumor of the submandibular gland, both of which were found on the left side. Case no. 2, a 62-year-old male was diagnosed as recurrent ameloblastoma of the mandible and adenolymphoma adjacent to a lower pole of the parotid gland.

Orthognathic treatment with maxillary and mandibular anterior segmental osteotomy

Abstract This case report presents a case that underwent orthognathic treatment with anterior segmental osteotomies on both jaws. The patient was a 26-year-old female with maxillary protrusion, lip incompetence with an everted vermilion border. The overbite was +1.0 mm, overjet +1.0 mm. The pre-surgical orthodontic treatment included the extraction of the four first premolars and a multi-bracket treatment was started. After 12 months of pre-surgical orthodontic treatment, both the anterior maxillary and the anterior mandibular segments were retracted surgically by 5.5 mm. The total treatment period was 18 months. An anterior segmental osteotomy can induce the remarkable structural changes for bimaxillary lip protrusion patients.