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Biomedical subjects

R B Mayhew

Publications and source records attributed to R B Mayhew.

34 records · Page 2Linked to original sources
PubMed1984

The validity of transcranial radiography in diagnosing TMJ anterior disk displacement.

Two transcranial radiographic methods for determining anterior disk displacement in the TMJ were evaluated in comparison with results obtained from arthrography. Both transcranial radiographic methods could only accurately predict the presence of an anteriorly displaced disk in a range of 26% to 56% of the time (for example, the methods gave false-negative results 44% to 74% of the time). The methods were more valuable in correctly identifying joints that were free of disease, achieving this identification anywhere from 64% to 96% of the time. Although noninvasive, these two transcranial radiographic techniques produced results that lacked validity and, therefore, remain of questionable value to the clinician who is diagnosing anterior disk displacement.

Cartilage, Articular↗
PubMed1984

The effects of two sharpening methods on the strength of a periodontal scaling instrument.

Several different techniques exist for sharpening periodontal scalers each of which will yield a relatively sharp instrument; however, some techniques may decrease the strength of the instrument more rapidly than others. The purpose of this study was to evaluate the effect of two different sharpening techniques on the strength of a periodontal scaler. Sixty McCall No. 13-14 scalers (SCI-DENT) were divided into groups of ten. Each group was reduced in size from 0 to 50% of a standard original size in increments of 10% by reducing the face of the instrument using an RX Honing Machine. A second set of 60 scalers was treated in a similar fashion by reducing the lateral surfaces of the instrument. Original angles and blade clearances were maintained on all instruments. Strength was measured by applying a force at a positive rake angle of 15 degrees in an Instron Testing Machine with a head speed of 50 cm/min. There were no significant differences in strength from grinding on the face vs. the lateral surfaces of the scaler in contrast to the observations of other investigators. Moreover, a 10 to 20% reduction can be accomplished before a significant drop in strength is observed by sharpening either the side or face of the instrument.

Dental Prophylaxis↗
PubMed1966

Isolation and characterization of Hydrogenomonas facilis bacteriophages under heterotrophic growth conditions.

Pootjes, Christine F. (The Pennsylvania State University, University Park), R. B. Mayhew, and B. D. Korant. Isolation and characterization of Hydrogenomonas facilis bacteriophages under heterotrophic growth conditions. J. Bacteriol. 92:1787-1791. 1966.-We have isolated five strains of bacteriophage specific for Hydrogenomonas facilis. The host range of the phage is limited to H. facilis. Morphologically, the phage particles consist of a head 580 A in diameter and a short tail 200 A in length. The particles share a common surface antigen, and all contain deoxyribonucleic acid. The five strains differ from each other in growth characteristics, heat stability, and neutralizing antigens.

Antigens↗