SEARCH · PubMed Health
Results for “Smiling”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Operation Smile: giving the gift of a smile.
Explore the source record for details and available documents.
There are smiles, and then there are smiles.
Explore the source record for details and available documents.
[Studies on the smiles rearrangement. 13. Reaction conditions on the smiles rearrangement in the 3(2H)-pyridazinone system].
Explore the source record for details and available documents.
Changing lives, one smile at a time: an operation smile mission to Machala, Ecuador.
Explore the source record for details and available documents.
The esthetics of the smile: a review of some recent studies.
PURPOSE: This article reviews recent research on the esthetics of the smile, covering the attractiveness of the smile, the effect of aging on the smile, oral condition and the smile, personality and smile, and smile exercises. MATERIAL AND METHODS: The subjects were Koreans with normal occlusion. Photographs of a full smile were taken and the esthetic quality of the subjects' smiles was estimated. Smile scores were correlated with oral condition, personality, the practice of smile exercises, and elements of the smile, such as the position of the lip in a smile. The personality of the subjects was assessed by means of a Sixteen Personality Factor Questionnaire. Gibson's smile exercises were used to investigate the effect of smile exercise. RESULTS: In an attractive smile, the full shape of the maxillary anterior teeth was shown between the upper and lower lip, the upper lip curved upward or was straight, the maxillary anterior incisal curve was parallel to the lower lip, and teeth were displayed to the first molar. The amount of maxillary incisal exposure gradually decreased with age, accompanied by a gradual increase in mandibular incisal exposure. Personality traits such as warmth, calmness, extroversion, and low anxiety were closely related to an attractive smile. Smile exercises were an effective means of improving the esthetic level of the smile if patients exercised continuously. CONCLUSION: An attractive smile is important for esthetic treatment. The lip position, oral condition, personality traits, and smile exercise affect the esthetics of the smile.
[Judgement of Authenticity of Smiles and Detection of Facial indexes].
The smile is one of the most often expressed emotions during social interactions. It can be authentic, that is, associated with a joyful emotional state in the person expressing it, but it can also be false, that is, deliberately produced in the absence of that emotional state in order to deceive one or more individuals (Ekman, 1993). Even though the fake smile very much resembles the authentic smile, it generally does not constitute the perfect simile. The fake smile more often has a certain degree of asymmetry than the authentic smile (Ekman, Hager, & Friesen, 1981) and it uses the cheek raiser action less often than with the authentic smile (Ekman, Friesen, & O'Sullivan, 1988; Frank, Ekman, & Friesen, 1993). This study looked at the knowledge that adults have of these differences as well as their perceptive ability to detect them. The visual stimuli presented to participants were prepared using the Facial Action Coding System (Ekman & Friesen, 1978). Results show that participants detected the differences between the two types of smile and that detection was better using smile asymmetry than with the cheek raiser action. Analysis of the use of response categories in the detection task indicated that participants underestimated the differences between smiles when they were different and that this tendency was more apparent with the cheek raiser detection method than for asymmetry detection. Participants also demonstrated a better knowledge of smile asymmetry than cheek raiser action. The knowledge gathered suggests that the ability of the receptor to judge smile authenticity is limited by perceptive factors. However, the mediation analyses that we conducted show the judging smile authenticity is not limited to simple perceptive detection of facial clues. Detecting facial clues is a necessary condition for correctly assessing smile authenticity, but it does not explain the variance in these assessments. We believe that this variance would be due more to the importance that participants give to facial clues. Finally, our results show that the capacity to detect differences between authentic and fake smiles is not easy to change. Participants who received modified information on changes of appearance linked to the two facial parameters were not more likely to detect the differences than participants who did not receive information.
A morphometric analysis of the posed smile.
A fundamental goal of orthodontics is to improve the smile, but no objective criteria exist to assess the lip-teeth relationship, establish objectives of treatment or measure treatment outcome. Here we propose a method to digitally measure the smile characteristics of orthodontic patients. Specifically, the 'posed smile' is measured. By definition the posed smile is voluntary and not elicited by an emotion. It can be a learned greeting or a signal of appeasement and can be sustained. The posed smile is reliably repeatable. The multimedia computer program for smile measurement we developed was based on studies of the utility of the smile photograph and the assessment of the lip-teeth characteristics of the posed smile in treated and untreated patients. On the computer screen a grid, or smile mesh, employs horizontal and vertical lines to measure eleven attributes of a smile. Not all orthodontically 'well-treated' patients with exemplary plaster casts exhibit desirable anterior tooth display while smiling. We suggest that the photographic analysis of an unstrained posed smile might be a standard orthodontic record.
Effects of candy and social reinforcement, instructions, and reinforcement schedule leaning on the modification and maintenance of smiling.
Two retarded boys exhibited abnormally low rates of smiling. In Exp. I, the frequency of a boy's smiling was first increased with candy reinforcement, but the frequency of the response did not decrease when candy reinforcement was terminated. When the subject wore a sign designed to make social interactions contingent on not-smiling, the frequency of smiling decreased. The sign was then changed to make social interactions contingent on smiling and the rate of smiling increased. In Exp. II, a second boy initially never smiled. Establishment of a contingency for candy reinforcement did not increase this zero response rate. Instructing the child to smile initially increased smiling, but the instructions then became progressively more ineffective. Candy reinforcement increased the rate of smiling to a normal range, but the rate of the response promptly decreased when this reinforcement was discontinued. Continuous candy reinforcement was again employed to increase the response rate and then progressively leaner schedules of variable-ratio candy reinforcement were employed. Consequently, the rate of smiling did not decrease when candy reinforcement was again eliminated. Subsequently, signs were employed to regulate social interactions and the rate of smiling was shown to be controlled by these interactions serving as reinforcers.
Physiotherapy rehabilitation of the smile after long-term facial nerve palsy using video self-modeling and implementation intentions.
OBJECTIVE: To improve smiling after long-term facial nerve palsy (FNP). Physiotherapy rehabilitation of an adapted (more symmetrical) smile was investigated in FNP subjects 1 year post-onset, using video self-modeling (video replay of only best adapted smiles) and implementation intentions (preplanning adapted smiles for specific situations). STUDY DESIGN AND SETTING: Prospective, blinded clinical trial. Facial-Nerve-Palsy Clinic. RESULTS: After video self-modeling: 1) reaction time (RT) to initiation of adapted smiles became 224 ms faster whereas RT for everyday (asymmetrical) smiles became 153 ms slower; 2) adapted smiles were completed 544 ms faster; 3) adapted smiles had higher overall quality, movement control, and symmetry ratings; and 4) Facial Disability Index scores also improved. Implementation intentions after video self-modeling ensured transfer of adapted smile to everyday situations. CONCLUSION: Following intervention the smile improved, with significant changes in availability, execution speed, and quality. SIGNIFICANCE: This study supports these rehabilitation techniques to maximize quality of smiling following FNP. EBM RATING: B-2b.
What's in a smile?
In positive social contexts, both adults and older infants show more Duchenne smiling (which involves high cheek raising) than non-Duchenne smiling (which does not). This study compared Duchenne and non-Duchenne smiles in early infancy for clues to their emotional significance. Infants (N = 13) from 1 to 6 months of age were videotaped weekly for 5 min in 208 face-to-face interactions with their mothers. Levels of Duchenne and non-Duchenne smiling were correlated within interactive sessions, and the 2 smiles had similar developmental trajectories. Duchenne smiles were typically preceded by non-Duchenne smiles. The results suggest these frequently contrasted types of smiles occur in similar situations and are often different temporal phases of a continuous emotional process. In contrast to adults, infant Duchenne smiles had longer durations than non-Duchenne smiles, suggesting infant smiling does not fit adult models of emotional functioning.
Behavioral markers and recognizability of the smile of enjoyment.
Ekman and Friesen (1982) predicted that smiles that express enjoyment would be marked by smoother zygomatic major actions of more consistent duration than the zygomatic major actions of nonenjoyment smiles. Study 1 measured the duration and smoothness of smiles shown by female subjects in response to positive emotion films while alone and in a social interaction. Enjoyment smiles in both situations were of more consistent duration and smoother than nonenjoyment smiles. In Study 2 observers who were shown videotapes of enjoyment and nonenjoyment smiles were able to accurately identify enjoyment smiles at rates greater than chance; moreover, accuracy was positively related to increased salience of orbicularis oculi action. In Study 3, another group of observers were asked to record their impressions of the smiling women shown in Study 2. These women were seen as more positive when they showed enjoyment compared with nonenjoyment smiles. These results provide further evidence that enjoyment smiles are entities distinct from smiles in general.
[The smile line, a literature search].
Beautiful teeth, visible when smiling, are in line with the present ideal of beauty. The display of teeth when smiling is determined by the smile line: the projection of the lower border of the upper lip on the maxillary teeth when smiling. On the basis of a literature search the determining methods of the smile line are discussed, demographic data of the position of the smile line are given, and factors of influence are examined. There is no unequivocal method for determining the position of the smile line. A rough distinction can be made between qualitative and (semi)-quantitative methods. The (semi)-quantitative methods have clear advantages for research purposes, but their reliability is unknown. It was demonstrated that among minimally 40% of subjects the maxillary gingiva was not visible when smiling. The mandibular gingiva was not visible when smiling among more than 90% of subjects. Furthermore, it appeared that among women the smile line was on average higher situated than among men and that it has not yet been proven that the smile line will be situated lower when growing older.
Facial and emotional reactions to Duchenne and non-Duchenne smiles.
The purpose of the study was to investigate facial and emotional reactions while viewing two different types of smiles and the relation of emotional empathy to these reactions. Facial EMG was recorded from the orbicularis oculi and zygomaticus major muscle regions while subjects individually watched two blocks of stimuli. One block included posed facial expressions of the Duchenne smile (a felt smile) and a neutral face, the other block included expressions of another type of smile called non-Duchenne smile (an unfelt smile) and a neutral face. Emotional experiences were asked after each stimulus block. Finally, a measure of empathy was given. Facial EMG reactions differentiated between the neutral face and the Duchenne smile but not between the neutral face and the non-Duchenne smile. The Duchenne smile block induced experience of pleasure for the subjects who saw it as the first stimulus block. Empathy was correlated to the rated experiences of pleasure and interest after the Duchenne smile block.
Attractiveness of variations in the smile arc and buccal corridor space as judged by orthodontists and laymen.
OBJECTIVE: To evaluate changes in attractiveness on the basis of computerized variations of smile arcs and buccal corridors for male and female smiles judged by orthodontists and laypersons. MATERIALS AND METHODS: Using a visual analog scale in a Web-based survey, orthodontists and laypersons rated the attractiveness of nine digitally altered smile arc and buccal corridor variations of male and female smiles. The variations were accomplished in a clinically relevant manner and based on standards set by experienced orthodontists in a pilot web-based survey. RESULTS: The results indicate that both laypersons and orthodontists prefer smiles in which the smile arc parallels the lower lip and buccal corridors are minimal. Significantly lower attractiveness ratings were found for smiles with flat smile arcs and excessive buccal corridors. Flattening of the smile arc overwhelms the deleterious effects of excessive buccal corridors on attractiveness ratings. CONCLUSIONS: On the basis of the results of this study, care should be taken not to produce an excessively flat smile arc during orthodontic treatment.
Localization of the cortical response to smiling using new imaging paradigms with functional magnetic resonance imaging.
Functional magnetic resonance imaging (fMRI) can serve to localize activity in the cerebral cortex. The present study was performed to develop a quantitative means of describing the cortical location activated during voluntary smiling in multiple subjects and to determine whether this location is specific to smiling when compared with other motor tasks. Five human subjects were instructed to smile or to tap the fingers of both hands. Both tasks were performed in a blocked-trial paradigm that consisted of alternating 15-second blocks of a repetitive motor task and 15 seconds of rest. Smiling was also performed as an event-related paradigm in which the subject smiled briefly once every 15 seconds for 20 repetitions that were combined to produce an average response to a single smile. A series of 300 images was acquired using an echo-planar imaging sequence (24-cm field of view; 5-mm slice thickness; repetition time/echo time, 1000/27.2 msec). Each subject's three-dimensional brain images were transformed to Talairach coordinates by stretching or compressing the brain images to fit the standard brain as defined in the Talairach atlas. This allowed data from five subjects to be combined for a numeric description. Functional activation maps acquired by use of the event-related paradigm contained significantly fewer motion artifacts than maps acquired with the blocked-trial paradigm, allowing better visualization of functionally active areas. Three-dimensional Talairach coordinates to describe the locations of peak cortical activity after smiling and finger tapping were established. These coordinates were consistent among subjects. During smiling, statistically significant activation was seen in the motor cortex, primarily along the precentral sulcus; this was inferior and anterior to the region that was associated with finger tapping. This study demonstrates that motion artifacts associated with traditional blocked-trial fMRI protocols can be overcome by employing an event-related paradigm to obtain an average response from a single smile. With the implementation of new imaging paradigms with fMRI, an area of the cerebral cortex has been identified that is specifically activated during voluntary smiling, and remains consistent among subjects. Quantification of fMRI data represents a powerful tool by which to study the cortical response to motor activity and to monitor possible alteration in this activity after injury or surgery. When combined with biofeedback therapy, this technique may help to improve the outcome of facial reanimation procedures in the future.
Smile reconstruction in adults with free muscle transfer innervated by the masseter motor nerve: effectiveness and cerebral adaptation.
BACKGROUND: This study assesses the ability of the masseter motor nerve-innervated microneurovascular muscle transfer to produce an effective smile in adult patients with bilateral and unilateral facial paralysis. METHODS: The operation consists of a one-stage microneurovascular transfer of a portion of the gracilis muscle that is innervated with the masseter motor nerve. The muscle is inserted into the cheek and attached to the mouth to produce a smile. The outcomes assessed were the amount of movement of the transferred muscle; the aesthetic quality of the smile; the control, use, and spontaneity of the smile; and the functional effects on eating, drinking, and speech. The study included 27 patients aged 16 to 61 years who received 45 muscle transfers. RESULTS: All 45 muscle transfers developed movement. The commissure movement averaged 13.0 +/- 4.7 mm at an angle of 47 +/- 15 degrees above the horizontal, and the mid upper lip movement averaged 8.3 +/- 3.0 mm at 42 +/- 17 degrees. Age did not affect the amount of movement. Patients older than 50 years had the same amount of movement as patients younger than 26 years (p = 0.605). Ninety-six percent of patients were satisfied with their smile. CONCLUSIONS: A spontaneous smile, the ability to smile without thinking about it, occurred routinely in 59 percent and occasionally in 29 percent of patients. Eighty-five percent of patients learned to smile without biting. Age did not affect the degree of spontaneity of smiling or the patient's ability to smile without biting.
Comparative study of smile analysis by subjective and computerized methods.
PURPOSE: This study compared: 1) the subjective analyses of a smile done by specialists with advanced training and by general dentists; 2) the subjective analysis of a smile, or that associated with the face, by specialists with advanced training and general dentists; 3) subjective analysis using a computerized analysis of the smile by specialists with advanced training, verifying the midline, labial line, smile line, the line between commissures and the golden proportion. METHODS: The sample consisted of 100 adults with natural dentition; 200 photographs were taken (100 of the smile and 100 of the entire face). Computerized analysis using AutoCAD software was performed, together with the subjective analyses of 2 groups of professionals (3 general dentists and 3 specialists with advanced training), using the following assessment factors: the midline, labial line, smile line, line between the commissures and the golden proportion. The smile itself and the smile associated with the entire face were recorded as being agreeable or not agreeable by the professionals. RESULTS: The McNemar test showed a highly significant difference (p=0.0000) among the subjective analyses performed by specialists compared to general dentists. Between the 2 groups of dental professionals, there were highly significant differences (p=0.0000) found between the subjective analyses of the smile and that of the face. The McNemar test showed statistical differences in all factors assessed, with the exception of the midline (p=0.1951), when the computerized analysis and subjective analysis of the specialists were compared. In order to establish harmony of the smile, it was not possible to establish a greater or lesser relevance among the factors analyzed.