To investigate perceived differences in the ability of current software to simulate the actual outcome of orthognathic surgery, we chose 10 difficult test cases with vertical discrepancies and "retreated" them using the actual surgical changes. Five programs-Dentofacial Planner Plus, Dolphin Imaging, Orthoplan, Quick Ceph Image, and Vistadent-were evaluated, by using both the default result and a refined result created with each program's enhancement tools. Three panels (orthodontists, oral-maxillofacial surgeons, and laypersons) judged the default images and the retouched simulations by ranking the simulations in side-by-side comparisons and by rating each simulation relative to the actual outcome on a 6-point scale. For the default and retouched images, Dentofacial Planner Plus was judged the best default simulation 79% and 59% of the time, respectively, and its default images received the best (lowest) mean score (2.46) on the 6-point scale. It also scored best (2.26) when the retouched images were compared, but the scores for Dolphin Imaging (2.83) and Quick Ceph (3.03) improved. Retouching had little impact on the scores for the other programs. Although the results show differences in simulation ability, selecting a software package depends on many factors. Performance and ease of use, cost, compatibility, and other features such as image and practice management tools are all important considerations. Users concerned with operating system compatibility and practice management integration might want to consider Dolphin Imaging and Quick Ceph, the programs comprising the second tier.To obtain true informed consent in orthognathic surgery, the orthodontist and the oralmaxillofacial surgeon must effectively explain possible treatment outcomes to the patient. It is difficult, if not impossible, to impart the facial appearance changes that will result from orthognathic surgery without visual aids. In the 1970s, clinicians used cut-and-paste profile tracings of patient photographs, which were neither realistic nor accurate. In the 1980s, computer-generated line drawings of the profile based on hard tissue changes became possible; by the mid-1990s, treatment simulation software allowing the incorporation of a patient's photographic likeness was offered commercially.At present, several software systems allow clinicians to manipulate digital representations of hard and soft tissue profile tracings and subsequently morph the pretreatment image to produce a treatment simulation. How well these predictions match the actual outcome of Copyright © 2004 NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript treatment has not been carefully evaluated, but anecdotal evidence suggests that the predictions might be less accurate when major vertical changes in jaw positions are planned. Most previous research involving computer simulation has focused on the accuracy of the predicted changes in the soft tissue points, by measuring the differences in soft and hard tissue landmarks on prediction and p...

Faces with threatening versus positive expressions are better remembered in visual working memory (WM) and are especially effective at capturing attention. We asked how the presence of a single threatening or happy face affects WM for concurrently viewed faces with neutral expressions. If threat captures attention and attention determines WM, then a WM performance cost for neutral faces should be evident. However, if threat boosts processing in an object-specific, noncompetitive manner, then no such costs should be produced. Participants viewed three neutral and one angry or happy face for 2 s. Face recognition was tested 1 s later. Although WM was better for singletons than nonsingletons and better for angry versus happy singletons, WM for neutral faces remained unaffected by either singleton. These results, combined with eye movement and response time analyses, argue against a selective attention account of threat-based benefits to WM and support object-specific enhancement via threat processing.

Learning allows the value of motivationally salient events to become associated with stimuli that predict those events. Here, we asked whether value associations could facilitate visual working memory (WM), and whether such effects would be valence dependent. Our experiment was specifically designed to isolate value-based effects on WM from value-based effects on selective attention that might be expected to bias encoding. In a simple associative learning task, participants learned to associate the color of tinted faces with gaining or losing money or neither. Tinted faces then served as memoranda in a face identity WM task for which previously learned color associations were irrelevant and no monetary outcomes were forthcoming. Memory was best for faces with gain-associated tints, poorest for faces with loss-associated tints, and average for faces with no-outcome-associated tints. Value associated with 1 item in the WM array did not modulate memory for other items in the array. Eye movements when studying faces did not depend on the valence of previously learned color associations, arguing against value-based biases being due to differential encoding. This valence-sensitive value-conditioning effect on WM appears to result from modulation of WM maintenance processes.

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