Oral Surgery, Oral Medicine, Oral Pathology最新文献

As the therapeutic options for malignant lesions expand, early accurate diagnosis of premalignancy is becoming increasingly important in the concept of cancer prevention. Because it has been hypothesized that abnormal cell proliferation is related to subsequent malignant transformation, many proliferation markers such as proliferating cell nuclear antigen have been studied in a variety of malignant tumors. In oral surface epithelium, proliferating cell nuclear antigen activity is restricted to basal layers of normal squamous mucosa. In this preliminary study, 169 formalin-fixed, paraffin-embedded oral epithelial lesions, including 28 carcinomas in situ, 82 epithelial dysplasias, 21 epithelial atypia, and 38 typical epithelial hyperplasias, were studied with a monoclonal antibody, PC10, to determine whether proliferating cell nuclear antigen suprabasal expression correlated with premalignancy. The findings revealed that with progression of lesions toward malignancy, there was a significant predilection for basal/suprabasal staining pattern for proliferating cell nuclear antigen as compared with the strictly basal staining pattern seen in normal and benign epithelial conditions. One unexpected staining pattern, suprabasal positive stain only, was also noted mostly in reactive hyperplasia and dysplasia. The data suggested that a positive basal/suprabasal staining pattern for proliferating cell nuclear antigen is indicative of premalignancy in oral epithelial lesions.

The transmission of blood-borne viruses in the dental office is a potential hazard to patients and dental staff, particularly to oral and maxillofacial surgeons. Hepatitis B virus has been a recognized hazard for several years, and in the past oral surgeons and other dental health care staff have been infected as a result of occupational exposure. Hepatitis C virus in contrast does not appear to be a major occupational hazard to dental staff, nevertheless, infection with this virus can lead to significant morbidity and may have oral manifestations. Hepatitis D virus can be nosocomally transmitted, but vaccination against the hepatitis B virus minimizes this problem. Hepatitis E virus is not of clinical relevance to dentistry, although dental staff who are in areas of endemic infection can become infected as a result of enteric transmission. A number of other putative viral agents may also cause hepatitis, but additional data is awaited, and their significance to dental practice is unknown. This article summarizes current data on hepatitis viruses A, B, C, D, and E.

The common houseplant, dieffenbachia, causes painful edematous swelling of the oral mucous membranes when chewed. This property, which is well known to the staffs of poison control centers, can be dangerous to the unwary or to victims of practical jokes. The microscopic features of the injury are those of acute inflammation, but the nature of the plant's toxicity remains controversial. The numerous needles (raphides) of calcium oxalate, which are contained in specialized cells (idioblasts) in the plant, and proteases have both been implicated. When stimulated, the idioblasts fire the raphides with some force for a distance of two to three cell lengths. One possibility is that the local toxicity of dieffenbachia may be caused by a combination of this mechanical release of the raphides, which results in traumatic injury, and the effects of a chemical toxin carried on their surfaces and in their grooves.

The reliability of two panoramic x-ray machines (Philips Orthoralix SD Ceph and Gendex Panelipse II) for determination of the location of the mandibular foramen was studied with the use of human dry mandibles. A significant correlation was found between the location of the mandibular foramen in the radiograph and the narrowest anteroposterior dimension of the ramus. A linear logistic regression equation was developed that could predict the actual location of the mandibular foramen from the radiographs. This finding will improve treatment planning of surgical splitting or fracturing of the ramus in cases that require orthognathic surgery provided the surgeon is aware of which panoramic machine was used. The Philips Orthoralix SD was found to be more reliable for this purpose than the Panelipse II (R² = 0.94 andR² = 0.87, respectively, in the vertical dimension and R² = 0.87 and R² = 0.75, respectively, in the horizontal dimension.

A case is presented in which an overfilling of obturation paste (N-2) extended through the lingual alveolar plate of bone as far as the insertion of the mylohyoid muscle. Pain was associated with the omolateral lingual soft tissues and the cervical region. A lingual flap retraction allowed removal of the paste, and the pain subsequently disappeared.

We report a previously undescribed gingival lesion composed of squamous epithelial islands in close association with bundles of nonmyelinated nerves. A review of the pertinent literature is presented and the histologic differential diagnosis is discussed. We suggest the termneuroepithelial hamartoma for this lesion.