Maxillary molars demonstrating more than one palatal root canal.

Maxillary molars exhibit variations in the canal morphology of the palatal root. Systems may occur in which a single palatal root contains two separate orifices, two separate canals, and two separate foramina. Other maxillary molars may have two separate palatal roots, each with one orifice, one canal, and one foramen. Another variation is one palatal root, one orifice, a bifurcated canal, and two foramina. The practitioner should be aware of variations in the canal system of the palatal roots of maxillary molars so that they can be treated more effectively.

Parent-peer influence as a predictor of marijuana use.

Although there is some literature which discusses adolescent reference groups, none have utilized reference group theory to examine the relative impact of the parent and peer reference groups and to attempt to predict behavior among teenagers from this knowledge. This study attempts to correct this deficiency by examining the frequency of marijuana use in a nonrandom sample of college students from a large southwestern university. Ordinal type scales and tau-b provide a statistically strong degree of association between the type of reference group orientation and marijuana use. The results of this study show that the influence of the most salient reference group appears to be an important predictor of whether or not an individual may engage in the use of marijuana.