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Biomedical subjects

R Shaye

Publications and source records attributed to R Shaye.

7 recordsLinked to original sources
PubMed1992

The effects of caffeine on the maxillary composition in the newborn rat.

The possible influence of caffeine on maxillary structure was studied. Seventeen pregnant rats at days 9 of gestation were randomly divided into two groups. The dams of group 1 received a 20% protein diet ad libitum throughout the experimental period. The dams of group 2 were pair-fed, with group 1, a 20% protein diet supplemented with 2 mg/100 g body weight (B.W.) caffeine. At birth, pups were mixed within the same group and 8 randomly selected pups were assigned to each dam and continuously fed the respective diet. On day 22, 11 male pups from the control and 12 males from the caffeine group were randomly selected, separated from the dams, and continued to be fed their respective diets. On day 44, a rubber elastic band was inserted between the first and second maxillary right molars. The size of the elastic band was increased throughout the next 5 days. Animals were sacrificed at day 49 and the composition of the maxillas was analyzed. After pulverization, organic and inorganic contents of the bones were measured. Zinc (Zn) and hydroxyproline concentration of the caffeine group showed a significant decrease when compared with those of the controls. However, Ca, P, Mg, and hexosamine concentration showed no difference between the groups. The interdental space measured occlusally and laterally with the visual method, and occlusally in histological sections showed no significant difference between the control and caffeine groups, although variation of the space in the caffeine group was less than in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1979

Interobserver reliability in xeroradiographic cephalometry.

Observer agreement on cephalometric landmarks was compared between xeroradiographs and conventional radiographs of twenty-nine patients. Of fourteen landmarks evaluated, four (condylion, infradentale, Ptm, and ANS) demonstrated clinical significance in favor of the xeroradiograph. In addition, six other landmarks favored the xeroradiograph but not to the degree of statistical significance.

Adolescent↗
PubMed1978

Landmark identification accuracy in xeroradiographic cephalometry.

Identification accuracy of fourteen cephalometric landmarks was compared between xeroradiographic cephalograms and conventional cephalograms. Four landmarks--point A, upper incisor tip, infradentale, and menton--were more accurately determined on the xeroradiograph, while two landmarks--point B and condylion--were more accurately determined on the conventional cephalogram. Although not conclusively demonstrated in this study, the xeroradiograph does appear to offer more clarity and detail than the conventional cephalogram. Further investigation of this new diagnostic medium will be necessary before its true significance to dentistry can be evaluated.

Cephalometry↗
PubMed1977

Management of cases with upper incisors missing.

A problem often confronting the orthodontist is that of missing upper incisors. In evaluation of the individual case, the dicision as to space closure or space regaining and eventual prosthetic reconstruction can be perplexing. Various diagnostic criteria, such as skeletal relation, arch-length analysis, inclination of teeth, and dental esthetics, must be evaluated. On the basis of this diagnostic information, treatment alternative is chosen to correct the malocclusion. The solution may be found in maintaining space, necessitating postorthodontic prosthetic replacement, or closing space and thus avoiding the need for artificial teeth. Four cases are shown to illustrate different approaches to the treatment of patients with upper incisors missing. Other solutions are possible anc correct. Each case must be weighed on its own merits.

Adolescent↗