Perceived Age and Personality Profiling after Orthognathic Surgery.

BACKGROUND: Recent studies suggest that orthognathic surgery can improve facial age and personality profiling. The authors expand on these findings by assessing the role of patient facial profile and sociodemographics on perceived changes following surgery. METHODS: Preoperative and postoperative images of 65 patients operated on by a single surgeon were randomly assorted and rated by 30 respondents. Patient facial profiles were categorized as convex, concave, or straight. Paired and unpaired t tests were used to assess differences preoperatively and postoperatively. Multivariate regression and post hoc receiver operating characteristic curve analyses were used to quantify the influence of various patient factors. RESULTS: Significant decreases in perceived age were seen following orthognathic surgery overall (-1.31 years; p < 0.01) and in the straight (-1.10 years; p = 0.02) and convex (-1.80 years; p ≤ 0.01) subgroups. After controlling for patient sociodemographics, there were no significant differences in age change based on facial profile. Older age at the time of surgery was independently associated with greater perceived age changes ( p = 0.04); older patients (>26.5 years, determined by receiver operating characteristic curve) experienced greater net decreases in perceived age in comparison to younger patients (-2.0 years versus -1.2 years; p < 0.01). Improvements were seen in overall attractiveness ( p < 0.01) and in each tested personality characteristic following surgery ( p < 0.01). These differences were not significantly associated with different patient sociodemographics or facial profile. CONCLUSIONS: The authors' data add to the growing base of evidence that orthognathic surgery improves patient-perceived age and personality. Significant decreases in perceived age are more likely to be gained by patients undergoing surgery at an older age. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Cargo transport shapes the spatial organization of a microbial community.

The human microbiome is an assemblage of diverse bacteria that interact with one another to form communities. Bacteria in a given community are arranged in a 3D matrix with many degrees of freedom. Snapshots of the community display well-defined structures, but the steps required for their assembly are not understood. Here, we show that this construction is carried out with the help of gliding bacteria. Gliding is defined as the motion of cells over a solid or semisolid surface without the necessity of growth or the aid of pili or flagella. Genomic analysis suggests that gliding bacteria are present in human microbial communities. We focus on Capnocytophaga gingivalis, which is present in abundance in the human oral microbiome. Tracking of fluorescently labeled single cells and of gas bubbles carried by fluid flow shows that swarms of C. gingivalis are layered, with cells in the upper layers moving more rapidly than those in the lower layers. Thus, cells also glide on top of one another. Cells of nonmotile bacterial species attach to the surface of C. gingivalis and are propelled as cargo. The cargo cell moves along the length of a C. gingivalis cell, looping from one pole to the other. Multicolor fluorescent spectral imaging of cells of different live but nonmotile bacterial species reveals their long-range transport in a polymicrobial community. A swarm of C. gingivalis transports some nonmotile bacterial species more efficiently than others and helps to shape the spatial organization of a polymicrobial community.