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The purpose of this study was to analyze the effect of various degrees of axial midline angulation on the attractiveness of a smile. We explored the influence of age, race, sex, direction of midline deviation, education, occupation, and dominant hand on each evaluator's perception of dental esthetics. Photographs of smiling subjects--one man and one woman--were altered to produce both left and right axial midline angulations in 5 degree increments. Fifty orthodontists and 50 laypeople evaluated these altered photographs by assigning both a numerical attractiveness rating and an acceptable or unacceptable rating to each. The results showed that attractiveness scores and acceptability ratings declined consistently as axial midline angulation increased. Statistical analysis showed that both sex of the subject and occupation of the judge were significant variables (P < .05) in the evaluation of the subjects. Age, race, sex of the judge, education level, direction of midline deviation, and dominant hand were not statistically significant. The mean acceptable midline angulation for the male subject was 6.6 +/- 4.5 degrees for orthodontists and 10.7 +/- 6.2 degrees for laypeople. For the female subject, the mean acceptable threshold was 6.4 +/- 4.0 degrees for orthodontists and 10.0 +/- 6.1 degrees for laypeople (P < .001). Discrepancies of 10 degrees were unacceptable by 68% of orthodontists and 41% of laypeople.

Neutrophil-independent macrophage responses are a prominent part of delayed-type immune and healing processes and depend on T cell-secreted cytokines. An important mediator in this setting is the phosphoprotein osteopontin, whose secretion by activated T cells confers resistance to infection by several intracellular pathogens through recruitment and activation of macrophages. Here, we analyze the structural basis of this activity following cleavage of the phosphoprotein by thrombin into two fragments. An interaction between the C-terminal domain of osteopontin and the receptor CD44 induces macrophage chemotaxis, and engagement of beta(3)-integrin receptors by a nonoverlapping N-terminal osteopontin domain induces cell spreading and subsequent activation. Serine phosphorylation of the osteopontin molecule on specific sites is required for functional interaction with integrin but not CD44 receptors. Thus, in addition to regulation of intracellular enzymes and substrates, phosphorylation also regulates the biological activity of secreted cytokines. These data, taken as a whole, indicate that the activities of distinct osteopontin domains are required to coordinate macrophage migration and activation and may bear on incompletely understood mechanisms of delayed-type hypersensitivity, wound healing, and granulomatous disease.

The purpose of this study was to determine whether proclination of mandibular central incisors during fixed appliance therapy results in gingival recession. Complete records of 67 patients (39 female and 28 male patients; mean age, 16.4 years; age range, 10-45 years) were used in this retrospective case-control study. Using pretreatment and posttreatment lateral cephalograms, the change in mandibular central incisor inclination was measured to divide the patients into an experimental group (proclination) and a control group (no proclination). Changes in clinical crown length were determined from pretreatment and posttreatment study models, and changes in gingival recession were determined from intraoral slides. Eight of the 67 patients exhibited a measurable increase in gingival recession of at least 0.5 mm, and 27 patients had an increase in clinical crown length of at least 0.5 mm. Statistical analyses showed no correlation between mandibular central incisor proclination and gingival recession or clinical crown length. A t-test analysis showed no statistically significant difference in gingival recession or change in clinical crown length between patients whose mandibular central incisors were proclined and those whose incisors were not proclined. Multiple regression analysis demonstrated that age, sex, race, treatment duration, extraction, treatment type, Angle classification, and proclination were not related to gingival recession or change in clinical crown length of mandibular central incisors. We conclude that the degree of proclination of mandibular central incisors during fixed appliance therapy was not correlated to gingival recession in this sample.

The purpose of this study was to identify and quantify the availability of orthodontic literature for evidence-based clinical decision-making (ie, sound clinical studies of etiology, diagnosis, treatment, or prognosis meeting basic methodologic criteria for direct clinical use). This is a first step toward developing online decision analysis systems. A search strategy based on Medical Subject Headings (MeSH) for orthodontics was developed to examine MEDLINE using the Ovid Web Gateway search engine. Sensitive and specific methodologic search filters were then employed to identify the 4 categories of information. The results were then subdivided by year to identify trends and sorted to identify source of publications. In the period 1990 to 1998, the MEDLINE searches identified 6938 English-language articles about orthodontics. The mean number of articles (+/-SD) per year ranged from 42+/-25 for specific searches to 314+/-214 for sensitive searches. The number of articles identified by the specific or sensitive searches increased 14% to 21% annually. When subdivided by clinical category, the mean numbers of articles per year for specific and sensitive searches were respectively: etiology 19+/-15 and 91+/-37, diagnosis 11+/-5 and 80+/-35, therapy 3+/-1 and 50+/-23, and prognosis 10+/-7 and 93+/-33. Five dental journals accounted for nearly half of these publications. These results provide several key findings: (1) there is a substantial literature of clinically relevant information in orthodontics upon which to base clinical decisions; (2) the information appears to be balanced between etiology, diagnosis, treatment, and prognosis; (3) approximately 45% of the articles reside in 5 journals, whereas the remainder reside in approximately 66 other journals, making it difficult to stay current; (4) the number of articles is increasing significantly each year; (5) to stay current, one would need to read between 1 and 6 articles per week, 52 weeks per year; (6) these trends suggest the need for computer-based clinical knowledge systems; and (7) the methods used here can be immediately employed to identify the best and most current clinical orthodontic evidence.

Cell-mediated (type-1) immunity is necessary for immune protection against most intracellular pathogens and, when excessive, can mediate organ-specific autoimmune destruction. Mice deficient in Eta-1 (also called osteopontin) gene expression have severely impaired type-1 immunity to viral infection [herpes simplex virus-type 1 (KOS strain)] and bacterial infection (Listeria monocytogenes) and do not develop sarcoid-type granulomas. Interleukin-12 (IL-12) and interferon-gamma production is diminished, and IL-10 production is increased. A phosphorylation-dependent interaction between the amino-terminal portion of Eta-1 and its integrin receptor stimulated IL-12 expression, whereas a phosphorylation-independent interaction with CD44 inhibited IL-10 expression. These findings identify Eta-1 as a key cytokine that sets the stage for efficient type-1 immune responses through differential regulation of macrophage IL-12 and IL-10 cytokine expression.