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Biomedical subjects

M Ulmansky

Publications and source records attributed to M Ulmansky.

At least 37 records · Page 2Linked to original sources

Dental abnormalities in aging sand rats (Psammomys obesus).

Sand rats transferred from their natural environment to laboratory conditions develop diabetes, cataracts, vertebral lesions, liver tumors, malocclusion and gingival inflammation. In the present study 43 sand rats of different ages were randomly chosen from a colony maintained for 13 years in the laboratory. Macroscopical, microscopical and radiographical examinations of the dental apparatus showed marked abnormalities in animals older than 6 months. The incisors were affected more than molars with an asymmetry between the right and left side of the jaw. Pathological alterations in the incisors included variations in length and curvature, lateral inclination, coronal fractures and pulpal calcifications. The enamel on the buccal aspect of these teeth had a scalloped appearance with corresponding metaplastic changes and folding of the ameloblastic layer. Coronal fractures were also found in molar teeth and were accompanied by marked hypercementosis. These changes are consistent with those reported in rodents with induced hormonal imbalance and may be associated with the diabetic state of aging sand rats. These gerbils are suggested as a model for studying the role of age-related disorders in the pathogenesis of certain dental abnormalities.

Age Factors↗

Primary mineralization in the interface between bone and methyl methacrylate implants in rat mandibles. A correlative light and scanning and transmission electron microscope study.

Self curing polymethylmethacrylate implants were administered into rat mandibular bone. Tissue reaction was studied after different periods with light microscopy and transmission and scanning electron microscopy. Formation of fibrous tissue in the interface between implant and bone was associated with initial bone resorption and followed by the occurrence of primary calcification in a collagen rich matrix after 4-8 weeks. The features of primary mineralization comprised appearance of hydroxyapatite crystals within matrix vesicles and formation of calcospheritic structures. The occurrence of calcifying fronts after the intraosseous administration of polymethylmethacrylate suggests a favourable relationship between bone and the implant material.

Animals↗

Unusual cyst of the zygoma.

An unusual cyst of the zygoma is described. Three patterns of development of the cyst are suggested, namely: 1. Residual cyst of retained deciduous roots with metaplasia of the odontogenic epithelium into respiratory epithelium. 2. Fissural cyst of the zygomatico-maxillary suture. 3. Connection to the maxillary sinus, by a developmental exvagination or trauma to the sinus that caused entrapment of epithelium at the fracture line, with subsequent proliferation.

Aged↗

Correlative clinico-pathological evaluation of oral premalignancy.

In 1972, the World Health Organization's "Meeting of Investigators on the Histological Definitions in Precancerous Lesions" defined a precancerous lesion as a "morphologically altered tissue in which cancer is more likely to occur than in its apparently normal counter part" (Pindborg 1980). There are two generally accepted precancerous lesions in the oral cavity, leukoplakia and erythroplakia (Pindborg 1980). Leukoplakia is currently defined as "a white patch or plaque that cannot be characterized clinically or pathologically as any other disease" (WHO 1978). This definition has no histological connotation and is used in a strictly clinical sense (Pindborg 1980, Banoczy 1977). Erythroplakia is defined as a "bright red velvety plaque which cannot be characterized clinically or pathologically as being due to any other condition" (Pindborg 1980).

Diagnosis, Differential↗

Effect of irradiation-timing on the initial socket healing in rats.

The effect of a single dose of 1500 R on early postextraction socket healing was studied in jaws of rats. A severe delay in healing was found in animals irradiated 2 weeks prior to extraction. Retardation of healing to a lesser degree was demonstrated in sockets irradiated immediately after exodontia.

Alveolar Process↗

Simultaneously occurring salivary gland tumors of different types.

Two cases of simultaneously occurring salivary gland tumors of the parotid gland are reported. Both patients were women in the sixth decade of life. In the first patient, a carcinoma in pleomorphic adenoma and an oncocytoma were found in the right parotid gland. The second patient had an adenoid cystic carcinoma associated with a sebaceous cell adenoma. The addition of these cases to the previously published data brings the total number of simultaneously occurring salivary gland tumors of different types to ten.

Adenoma↗

Structural changes in odontodysplasia.

Report is made of a histologic and scanning electron microscopic (SEM) study of teeth affected by odontodysplasia. The enamel was found to be thinner than normal, and the entire surface showed numerous depressions. The prismatic orientation, diameter, and density were found to be normal. Although the mantle dentin remained normal, the rest of this tissue showed a tendency to globular formation. The orientation, density, size, and shape of the dentinal tubules appeared to be normal. The cementum, in general, was normal, but in some instances appeared to be scalloped or globular. The pulp consisted of normal tissue but was found to be larger than normal. The presence of denticles was an outstanding feature.

Dental Enamel↗

Antibodies in the saliva after antigenic challenge of the parotid gland of systemically sensitized rats.

Anti-BSA antibodies were detected in the parotid saliva of untreated rats. In non-sensitized animals, the parotid duct of which was repeatedly instilled with saline or BSA, the antibody titers rose significantly. Introduction of BSA into the parotid gland of sensitized animals was followed by a significant rise in salivary but not in circulating antibodies. The findings demonstrate the relative independence of the local from the systemic immune system.

Animals↗

Odontodysplasia. Report of two cases and review of the literature.

Odontodysplasia is a rare developmental anomaly affecting the tooth structures in both deciduous and permanent dentitions. The enamel is thin and uneven in thickness, and the detinal tissue surrounds very large pulp chambers. Denticles are present in the pulp organ. The maxilla is involved twice as frequently as the mandible. Most of the affected teeth are in the anterior segments; however, all other teeth can be affected. The cause is unknown. Because of the tendency of the affected teeth to develop abscesses, the most common treatment is extraction. Two additional cases are reported, and the literature is reviewed.

Abscess↗

Adaptation of silicate and Adaptic to the margins of cavities. A scanning electron microscope study.

The effects of etching of the enamel, on the adaptation of silicate and Adaptic to the cavity walls was examined with the scanning electron microscope. Replica methods were utilized to ensure that no shrinkage of the filling materials was caused by the vacuum in the instrument. It was shown that following etching of the cavity margins, Adaptic adhered to the enamel with absent, or minimal, fissure formation on one side of the filling, and some on the opposite side. The adaptation of silicate to the margins of the cavities was not improved by etching.

Composite Resins↗

The effect of local anesthetic solutions on the blood vessels of the rat molars.

The effect of solutions of lidocaine, with and without adrenaline, on the blood vessels of the dental pulp and periodontal ligament in rat molars was examined. The vessels were visualized by intravascular injection of a supension of carbon particles. The results indicate that the anesthetic solution alone does have a local effect on the blood vessels. Local anesthetic solutions containing adrenaline had a more marked effect; in addition, a dose-dependent systemic effect of adrenaline was noted.

Animals↗