Yoshiyasu Fukuta

Evaluation by dental cone-beam computed tomography of the incidence and sites of branches of the inferior dental canal that supply mandibular third molars.

Our aim was to assess the incidence and anatomical site of branches of the inferior dental canal that supply mandibular third molars using dental cone-beam computed tomography (CT). We evaluated the incidence and diameter of branches of the inferior dental canal using 272 cone-beam CT mandibular scans from 172 patients referred for imaging before the extraction of impacted mandibular third molars. We found three typical branching patterns from the inferior dental canal in the third molar region: the retromolar canal (in the retromolar triangle), the dental canal (that courses directly beneath the socket of the third molar), and the accessory canal (that courses through the socket and leads from the inferior dental canal to a bony ridge). The incidences of retromolar, dental, and accessory canals were 75 (28%), 223 (82%), and 21 (8%), respectively, with mean diameters of 0.9 (0.4), 0.7 (0.5), and 1.1 (0.4) mm, respectively. Operative injury to the neurovascular contents within the branches of the inferior dental canal can lead to excessive bleeding and postoperative paraesthesia, so identification of its branches on preoperative cone-beam CT images may prove useful during extraction of impacted mandibular third molars or when harvesting bone blocks from the region of mandibular third molars. We also describe two cases of branches detected on panoramic and cone-beam CT images that prompted this research.

Hyaline Ring Granuloma of the Mandibular Periosteum

Abstract Hyaline ring granuloma (HRG) is a comparatively rare inflammatory condition occurring mainly in the oral region, and is characterized by hyaline rings (HRs) formed in the granulation tissue. This study describes a case of HRG occurring in the mandibular periosteum of an 18-year-old male. Histopathologic, histochemical and electron microscopic studies were performed on surgically excised materials. Histopathologically, ovoid bodies(OBs) surrounded by thin hyaline walls and HRs showing pale-stained eosinophilic thick hyaline walls were both detected. Histochemical study revealed that the OBs contained many granules chiefly composed of starch. Ultrastructurally, the HRs presented a stratiform structure due to the accumulation of cross-banded collagen fibrils with a basement membrane-like lining containing cellulose microfilaments. These results suggest that HRs are formed as follows: the exogenous vegetable materials are encapsulated by collagen, then the component is gradually degraded; the residual cellulose fraction adheres to the inner surface of the collagenous capsules, and the continuous deposition of collagen at the outer surface of the capsules increases its thickness. Finally, thick hyaline walls of HRs are formed. The possible pathogenesis of this curious lesion is discussed for stomatologists.

Long-term restoration of masticatory function with fixed mandibular implants in cases of oral cancer.

The results of the present study show that the fixed mandibular implant system enables patients who have operations to treat oral cancer to use a stabilized denture continuously over an extended period of time.

A locally advanced tongue cancer responding to combination chemotherapy with UFT-E granule and Leucovorin tablet.

患者は68歳の女性で, 左側舌側縁に高分化型扁平上皮癌 (T3N0M0) を認めた。初診時よりUFT-E顆粒450mg/日の経口投与を開始し, 腫瘍の縮小傾向がみられたため3週間後よりbiochemical modulationによる腫瘍縮小効果増強を期待しLeucovorin 30mg/日を併用した。腫瘍は臨床的に消失したため, 全麻下に舌部分切除術を施行した。退院後, 義歯を装用し, 会話や嚥下機能にも特に問題ない。現在術後5年2か月を経過しているが再発や転移を認めず良好に経過している。

Combined treatment for two advanced carcinomas of the buccal mucosa with local hyperthermia.

頬粘膜進展癌の2例に対し温熱療法を組み入れた集学治療を施行し, 良好な経過を辿っているので報告する。症例1: 61歳, 男性。高分化型扁平上皮癌 (T3N2bM0) で, 治療はPM療法5クール (PEP1回2.5mg計72.5mg, MMC1回10mg計50mg) , 60Co36Gy, 温熱療法を頬部に5回, 頸部に6回, OK-432を総量44.5KE投与し, 左側全頸部郭清, 腫瘍切除, D―P皮弁による頬部全層欠損の即時再建術を施行した。症例2: 69歳男性, 高分化型扁平上皮癌 (T4N2bM0) 。右側浅側頭動脈を用いてCDDP150mg, PEP70mg, 5-FU1回125mg計2000mgを動静注し, 60Co照射を頬部, 頸部にそれぞれ40.5Gy, 60.5Gy併用した。さらに温熱療法を頸部に9回併用し, OK-432を術前に総計40.4KE投与した。1988年6月7日, 右側全頸部郭清, 腫瘍切除, 植皮術を施行した。初診より4年と2年7か月経過した現在、再発・転移なく経過良好である。2例とも重大な合併症も無く, 予定の化学療法, 放射線療法が施行でき, 根治的手術が可能であったことが良好に経過している要因と考えられた。