Biomedical subjects

D V Provenza

Publications and source records attributed to D V Provenza.

At least 37 records · Page 2Linked to original sources

PubMed1977

Molar odontogenesis in the hairless mouse.

Molar odontogenesis was studied in the hairless mouse from the initiation of the dental lamina through apposition. The dental lamina stage of the first molar was recognized on the 13th day, the bud on day 14th, cap on the 16th, bell on the 18th and apposition on the 20th day after conception. The morphology of the various stages and their temporal sequence were compared with those of other rodents.

Animals↗

PubMed1977

Effects of ionizing radiation on incisor development of the prenatal mouse.

The effects of 100 rad of X-irradiation of incisor development in CD1 mice were studied. 24 pregnant mice were irradiated on the 12th day post coitum and sacrificed from the 14th through the 20th gestational days. The 191 irradiated fetuses were smaller than those not irradiated, their crania and necks were malformed and their lower extremities were poorly developed. The developing incisors of the irradiated animals were retarded, the pulpal vessels were enlarged and the vessels walls did not maintain their structural integrity. The cells of the future pulp were necrotic, and the basement membranes appeared hyalinized. Ameloblasts and odontoblasts were abnormal in morphology and the formation of dental hard tissue was inhibited in places. Complete absence of incisor tooth germ was noted in three of the fetuses.

Animals↗

PubMed1976

Aryl sulfatase activity in mouse molar odontogenesis.

Arylsulfatase activity has been studied in the developing molar of the Swiss albino mouse from the lamina stage to the appositional stage. Timed-pregnant Swiss albino mice were utilized in this study. Females were sacrificed by ether anesthesia and fetuses extirpated or newborns anesthetized and decapitated. Frozen sections were fixed and incubated for arylsulfatase activity according to a modification of the method of PEARSE (1972). The tissue was dehydrated, cleared and covered. Phase light microscopy was utilized in evaluating arylsulfatase activity in the developing molar. Arylsulfatase activity was evaluated for each stage of development and the results presented in tabular form. The present investigation represents the first known effort to describe arylsulfatase activity in odontogenic tissues from the initiation of the dental lamina through the appositional stage. Arylsulfatase activity appeared to be related to the degree of vascularization of the developing enamel organ and adnexa and the beginning of hard tissue elaboration.

Animals↗

PubMed1976

Development of the squamosomandibular articulation in the Mongolian gerbil (Meriones unguiculatus).

The early development of the squamosomandibular articulation in the Mongolian gerbil was investigated from its inception through the 8th postnatal day. Pregnant gerbils were sacrified beginning on day 18 through day 23 of gestation by chlorofrom inhalation and the fetuses were extirpated and decapitated. Neonatal gerbils, 1-8 days of age, were also sacrificed. The severed heads were frozen in a cryostat and sectioned at 14mum in frontal and transverse planes and stained in 1% aqueous Safranin 0. The anlage of the mandibular joint along with membranous bony deposits lateral to Meckel's cartilage in the vicinity of the presumptive body and ramus first appeared on the 18th gestational day. Condylar chondrogenesis occurred on the 20th prenatal day, and by day 22 of gestation chondrocytic hypertrophy was noted preparatory to osteogenesis. The presumptive articular disc was observed on the 21st gestational day while an upper and lower synovial cavity was discernible on the 22nd prenatal day. The squamosa and zygoma were first noted on the 20th postcoital day. There appeared to be a developmental lag from onset through completion of the gerbil squamosomandibular joint formation in comparison with that reported for the mouse and rat.

Age Factors↗

PubMed1976