A total of 78 bacteriological samples were taken from the supragingival tooth surface after superficial cleaning with toothpicks or from the periodontal sulci of 42 affected sites in 21 adolescents or young adults with severe generalized periodontitis. Of 190 bacterial species, subspecies, or serotypes detected among 2,723 isolates, 11 species exceeded 1% of the subgingival flora and were most closely associated with the diseased sulci. Eleven others were also sufficiently frequent to be suspect agents of tissue destruction. Many of these species are known pathogens of other body sites. In addition, 10 species of Treponema were isolated. One of these and the "large treponeme" were also more closely associated with severe periodontitis than they were with healthy sites or gingivitis. There were highly significant differences between the composition of the flora of the affected sulci and the flora of (i) the adjacent supragingival tooth surface, (ii) the gingival crevice of periodontally healthy people, and (iii) sites with a gingival index score of 0 or 2 in experimental gingivitis studies. The floras of different individuals were also significantly different. There was no statistically detectable effect of sampling per se upon the composition of the flora of subsequent samples from the same sites. The composition of the supragingival flora of the patients with severe generalized periodontitis that had serum antibody to Actinobacillus actinomycetemcomitans was significantly different from the supragingival flora of patients without this serum antibody. However, there was no statistically significant difference in the composition of their subgingival floras.

Statistical comparisons of the floras associated with juvenile periodontitis, severe periodontitis, and moderate periodontitis indicated that differences in the bacterial compositions of affected sites in these populations were not statistically significant. The subgingival flora of affected juvenile periodontitis sites was statistically significantly different from the adjacent supragingival flora and from the subgingival floras of people with healthy gingiva and of children with developing (experimental) gingivitis. However, the subgingival flora of affected juvenile periodontitis sites was not significantly different from the flora of sites with gingival index scores of 1 or 2 in adults with developing (experimental) gingivitis. Of 357 bacterial taxa among over 18,000 isolates, 54 non-treponemal species, 2 treponemal species, and mycoplasma were most associated with diseased periodontal sulci. These species comprised an increasing proportion of the flora during developing gingivitis * Corresponding author.

The subgingival bacterial floras of naturally occurring gingivitis in adults and children were characterized and compared with the floras of other periodontal conditions previously studied. The composition of the gingivitis floras was found to be distinct from that of floras associated with health or with moderate, severe, or juvenile periodontitis. There were no major differences between the floras of naturally-occurring gingivitis and the floras of the human experimental gingivitis model. Data indicated that the flora of healthy sites within a mouth is influenced by the number of inflamed sites, which argues against independence of sites bacteriologically. Proportions of ten bacterial species increased in both gingivitis and periodontitis, as compared with health, in both adults and children. These species were found in both affected and unaffected sites of people with gingivitis. The numbers of five other cultivable species and the "large treponeme", which was not cultivated, increased in gingivitis and periodontitis of adults only. Significant differences in non-spirochetal floras between children and adults were not found, although they were in the experimental gingivitis model studied previously. Cultivable spirochetes did differ between children and adults. Children had fewer samples positive for spirochetes, and children's positive samples contained greater proportions of T. socranskii subsp. paredis. Some species that predominate in periodontitis, but which are absent from healthy gingivae, were found as a small percentage of the flora in gingivitis. This suggests that increased serum and blood in the gingival crevice encourage species that relate to periodontitis.

This 2009 study of dental school curricula follows a similar one conducted in 2002-03. Through a web-based survey, the authors gathered information from dental schools about 1) past trends in curricular change over seven years; 2) current changes under way in dental school curricula; 3) significant challenges to curricular innovation; and 4) projected future trends in curricular change and innovation. Fifty-five schools (fifty U.S. and five Canadian) responded to the survey for a response rate of 86 percent. In addition to background information, the survey requested information in four broad areas: curriculum format, curriculum assessment, curriculum innovation, and resources needed for curriculum enhancement. Forty-nine percent of the respondents defined their curriculum format as primarily organized by disciplines. Half of the respondents reported the use of problembased and case-reinforced learning for a section or specific component of some courses. In a significant change from the 2002-03 study, a high proportion (91 percent) of the responding schools require community-based patient care by all students, with just over half requiring five or more weeks of such experience. Competency-based education to prepare an entry-level general dentist seems well established as the norm in responding dental schools. Forty-three percent or less of the responding schools indicated that their students participate with other health professions education programs for various portions of their educational experience. Since the 2002-03 survey, dental schools have been active in conducting comprehensive curriculum reviews; 65 percent indicated that their most recent comprehensive curriculum review is currently under way or was conducted within the past two years. Respondents indicated that the primary reasons for the configuration of the current curriculum were "perceived success" (it works), "compatibility with faculty preferences," "faculty comfort," and "capacity/feasibility." Key catalysts for curricular change were "findings of a curriculum review we conducted ourselves," students' feedback about curriculum, and administration and faculty dissatisfaction. There was an increase in the percentage of schools with interdisciplinary courses, especially in the basic sciences since 2002-03, but no change in the use of problem-based and case-reinforced learning in dental curricula. Respondents reported that priorities for future curriculum modification included creating interdisciplinary curricula that are organized around themes, blending the basic and clinical sciences, provision of some elements of core curricula in an online format, developing new techniques for assessing competency, and increasing collaborations with other health professions schools. Respondents identified training for new faculty members in teaching skills, curriculum design, and assessment methods as the most critical need to support future innovation.Dr.

A total of 171 taxa was represented among 1,900 bacterial isolates from 60 samples of sites affected with moderate periodontitis in 22 mature adult humans. The composition of the subgingival sulcus flora was statistically significantly different from that of the adjacent supragingival flora and the subgingival flora of 14 people with healthy gingiva, but was not significantly different from that of sulci affected with severe periodontitis in 21 young human adults. The sulcus floras of moderate periodontitis and severe periodontitis shared many of their predominant bacterial species, but there were differences in the relative proportions of some of these species. Similar relationships were found for seven taxa of treponemes that were cultured from the samples.