Idiopathic resorption of teeth. A report of three cases.

External resorption of teeth is a condition typically associated with etiologic factors within the adjacent alveolar bone, such as chronic periapical or periodontal infections, neoplasms, erupting permanent teeth, orthodontic movement, or trauma to the jaws. When none of these causes are present, resorption of teeth at the cementoenamel junction has been termed "idiopathic resorption of teeth." Three cases of idiopathic resorption of teeth are reported, the literature on previous cases is reviewed, and hypotheses as to causes and a new theory are postulated regarding the possible mechanism for osteoclastic resorption of teeth.

Desmoplastic fibroma of the maxilla.

A case of desmoplastic fibroma of the right maxilla is reported. The lesion presented as a painless mass in the right posterior alveolar ridge of a 22-year-old white man. Histologically, the lesion was composed of interlacing fascicles of benign-appearing fibroblasts in a varying ground substance of collagenous and myxoid tissue. The lesion was not encapsulated histologically and was invading between bone trabeculae resulting in resorption of the bone. A review of the literature reveals that a total of 30 cases of desmoplastic fibroma of the jaws have been reported. All of the mandibular lesions except two were reported to have occurred in the left side, with the molar-ramus region favored. The case reported here is, to the best of our knowledge, the first reported case of desmoplastic fibroma occurring in the maxillary alveolar process.

Backscattering from dental restorations and splint materials during therapeutic radiation.

Models were constructed to simulate as closely as possible the human oral cavity. Radiation absorbed doses were determined for controls and various test situations involving the presence of dental restorative and splint materials during cobalt-60 irradiation of the models. Adjacent gold full crowns and adjacent solid dental silver amalgam cores both increased the dose to the interproximal gingivae by 20%. Use of orthodontic full bands for splinting the jaws increased the dose to the buccal tissues by an average of 10%. Augmentation of dose through backscatter radiation was determined to be only slight for intracoronal amalgam fillings and stainless steel or plastic bracket splints.

Computerized tomography of combined carcinomas arising in pleomorphic adenoma.

A case of carcinoma ex pleomorphic adenoma of the palate and maxillary sinus is reported. Unlike most such cases, there were two distinct malignant components: adenoid cystic carcinoma and adenocarcinoma. The computerized tomography of this lesion is described.

Intraneural epithelial islands associated with a periapical cyst.

Epithelial islands associated with nerve bundles have been reported in the mandible and maxilla. An example of such intraneural rests is reported in association with a radicular cyst. The differential diagnosis of intraneural epithelial islands must include benign odontogenic rests, remnants of nasopalatine duct in the anterior maxilla, the organ of Chievitz, and neural invasion by a carcinoma.

A review of drug transfer to the infant by breast-feeding: concerns for the dentist.

The nursing infant, not being a miniature adult, has physiologic differences that need to be considered when he or she is subjected to drugs through breastfeeding. These differences may include an immature liver, decreased albumen levels, and an inability to excrete agents in the urine and stool. Besides immediate pharmacologic effects, possible long-term complications of each drug need to be considered. As can be seen from the data, many drugs that are prescribed by the dental profession are not considered hazardous to the nursing infant. However, this generalization is not appropriate for individual patients, and the prescribing dentist is advised to administer systemic drugs to lactating mothers with discretion and close follow-up.

The expression of the epithelial blood-group substances: normal and malignant tissues.

The blood-group isoantigens are macromolecules localized to the plasma membranes of certain epithelial tissues. These substances are not detectable on the epithelium once it has undergone malignant transformation. Results of this investigation have demonstrated that the loss of detectability of the blood-group isoantigens does not appear to be related to a "masking" effect by an increase in surface sialic acid. Using fluorescein-labeled lectins specific for sugar subunits which are components of the blood-group oligosaccharide chain, it was found that the malignant cells and cells of the parabasal layer of normal oral epithelium had high levels of N-acetyl-D-glucosamine (GlcNAC), the subterminal sugar residue of the blood-group chain. The basal cells of normal epithelium and a minority of the malignant cells demonstrated levels of D-galactose-N-acetyl-D-galactosamine, which are the most proximal blood-group sugar subunits, as well as subunits of other membrane antigens. Our results indicate that malignant cells seem to be capable of synthesizing the blood-group oligosaccharide chains to the same level as the normal cells of the parabasal layer of stratified squamous epithelium. This level is just subjacent to the terminal D-galactose residue of the blood-group precursor chain. Increased or decreased differentiation characteristics of squamous cell carcinomas did not alter the level of blood-group synthesis. However, there may be a correlation between the level of synthesis of these antigens and the ability of the cells to demonstrate motility and to proliferate.