Facial recession defects were created on maxillary canine teeth of six Macaca irus monkeys and left untreated and exposed to oral fluids for 6 to 12 weeks. Notches were placed in the exposed root surfaces at the level of the free gingival margins. Following root planing with the addition of topical citric acid application on experimental surfaces, pedicle flaps were coronally positioned over the previously exposed roots. After euthanasia, block sections representing postsurgical time periods of 0, 3, 7, 14, 21, 28 and 42 days were secured and tissues were processed for histologic evaluation. All citric acid-treated surfaces exhibited new connective tissue attachment of pedicle flaps to previously exposed areas by 14 days with transmission electron micrographs confirming beginning cementum deposition. In contrast, controls demonstrated epithelial migration to, or apical to, reference notches. Although the total number of samples available for statistical comparison was small, a two-tailed t test for correlated samples showed citric acid application did not result in enhanced clinical root coverage, but did result in significantly greater amounts of new connective tissue attachment (P less than 0.05, df = 3). Pedicle flap healing against teeth with devital pulps was identical to that seen in teeth with vital pulps, while citric acid application to root-planed surfaces of vital teeth had no observable effect upon pulpal tissues.

Observations on the apical part of the flagellar pocket of Trypanosoma brucei using the freeze-cleaving and thin-sectioning techniques of electron microscopy are reported. The flagellar pocket is shown as a flask-shaped depression in the body, continuous with the pellicle and flagellar sheath. The membranes of the apical part of the pocket on the flanged side of the body compress the flagellar sheath, forming part of a "neck region". This region is completed on the broad body side of the flagellar pocket when it embraces the flagellar sheath. The possible role of the neck region in the dynamic function of pinocytosis is discussed.

Pathogenic Entamoeba histolytica trophozoites were studied by the freeze-etching (FE) technique of electron microscopy. Surface replicas of intact cell membranes were highly convoluted with numerous invaginations, evaginations, and undulations. Sperical depressions and elevations varying from 0.5 mu to 1.0 mu in diameter were commonly present on the external cell membrane and appeared to represent an extracellular secretory mechanism of trophozoites. Cleaved surfaces of amebae exhibited a granular and lumpy cytoplasm in which there were many vesicles and vacuoles that ranged in diameter from 0.2 mu to 9.0 mu. Some vacuoles contained tightly enveloped bacteria, while others contained bacteria and host cytocomponents. Occasional vesicles and vacuoles appeared to be fused to each other. Replicas of FE nucleus were enclosed by double nuclear membranes which were fenestrated by numerous sperical pores measuring approximately 640 A in diameter and spaced at intervals of 650 A. Counts of nuclear pores were possible and indicated 35 pores per square micron on the nuclear envelope. Golgi apparatus, mitochondria and well formed endoplasmic reticulum were absent in FE replicas. This was in agreement with electron microscope observations on thin sections previously reported by other investigators.

As health care practitioners, dental hygienists need information-gathering skills and the conidence to both perform literature searches in Internet databases and assess the results in order to utilize the wealth of scientiic literature that supports evidence-based practice. The aim of this study was to assess the information-seeking strategies of dental hygienists. A self-administered electronic survey of thirty-eight questions was sent to 5,007 licensed dental hygienists in District III of the American Dental Hygienists' Association. The overall response rate was 7.9 percent (396/5,007). Most (90.9 percent) of the respondents were currently practicing dental hygiene, with 62.9 percent having practiced more than ten years. Approximately 56 percent had graduated from a two-year dental hygiene program and had graduated before 1998. Nearly all of the respondents who graduated in 1999 or after were conident using a computer (96.2 percent) and the Internet (95.4 percent); lower percentages of the pre-1999 graduates expressed such conidence (68.6 percent using a computer and 80.7 percent using the Internet). Most respondents (90.9 percent) who graduated in 1999 or after reported receiving evidence-based decision making (EBDM) training in their dental hygiene program-an increase over the 51.8 percent of pre-1999 graduates who reported having received it-though lower percentages (78.2 and 48.0 percent, respectively) reported thinking their EBDM training was adequate. Though the response rate was low, these results may suggest that information-gathering skills are being more effectively addressed in recent dental hygiene education than previously. Continuing education courses that teach hands-on navigation of databases and methods to search the scientiic literature and analytically appraise it could increase both the skills and comfort level of dental hygienists, especially those who graduated more than a decade ago.

Many institutions do not perform statistical modeling of student academic outcomes because they lack the ability to translate Banner® relational files to a flat-file database format. Accredited programs within institutions have terminal, high stakes examinations known as certifying boards that measure competencies and subject knowledge gained during the educational experience. Institutions need to know if there is a relationship between what is being taught throughout the curriculum and how well that knowledge prepares students to think critically as reflected by performance on boards. While it is easy to download Banner data in Microsoft Excel® spreadsheet format, programmers are needed to parse the file for use in statistical packages such as IBM SPSS® and SAS®. This case study details a methodology, including programming language, that will help anyone with intermediate Excel knowledge develop a relational database from Banner files.

There are several excellent indices available to quantify diversity within a student body. Richness and evenness can be studied using Simpson’s Index with its associated Reciprocal Index, and with Shannon-Weiner’s Index “H” and Index “E”. Lieberson provides the means to measure isolation and interaction, and Dissimilarity works well to identify segregated communities. Results using these indices show that the Historically Black College of Dentistry is a culturally vibrant and diverse academic and social environment. White students at the Historically Black College of Dentistry are more likely to enjoy interaction with other Whites than will Historically Black and Hispanic students at all other dental schools, except at the other Medical College, the only other HBCU with a dental school. Overall, there was no statistical diversity difference between the Historically Black College of Dentistry and all other dental schools over the 10 year study period. Statistically significant correlations between each index provided a framework for using each index in prediction modeling. Recent methods to manage multi-collinearity, such as extracting unstandardized residuals to use as adjusted coefficients add promise that all indices can be used in future diversity studies.