Establishment of a new relationship between posed smile width and lower facial height: A cross-sectional study

The perception of smile attractiveness to altered vertical position of maxillary anteriors by various groups

There is a gap in research about the differences in smile attractiveness. The problem the study addresses is how the vertical canine and incisor position affect smile attractiveness. The aim of this study was to assess the perception of the smile attractiveness between Saudi laypersons, orthodontists, non-orthodontist, and various dental students levels, and to determine how the canine and incisor vertical positions affect the attractiveness of smile. The study is a cross-sectional survey and was conducted at King Abdulaziz University, Jeddah, Saudi Arabia. Six groups of subjects participated in the study: Orthodontic residents (n = 31), prosthodontic, restorative, periodontics specialties residents specialties residents (n = 30), interns (n = 31), fifth year students (n = 41), 6th year students (n = 39), and laypeople (n = 39). Participants were asked to rate the attractiveness of a smile of a female subject photographed using a Minolta DiMage 7i digital camera. The image had been manipulated to produce 2 sets of images; 1 to modify the incisors and 1 to change the canines. The subjects were asked to choose the most and least attractive picture. For the best incisor positions, only the laypeople and prosthodontics liked the original picture, the rest liked +0.5 mm which accentuate the smile curve and make it follow the lower lip line. For the worst incisor position, all groups did not prefer the minus 1.5 reversed smile. For the best canine vertical position, all groups preferred the original position where canine was at the level of the incisal plane. For the worst canine position, they all disliked the minus 1.5 reversed smile. Results confirmed past findings that orthodontists are in general more critical about smile attractiveness than laypersons, but just like other dental specialists. The findings can be used in the esthetic dentistry field, but further research on the study population based on other dental design parameters remain necessary.

Evaluation of smile characteristics of skeletal Class III compared to skeletal Class I female adults

OBJECTIVE:

Esthetic enhancement plays an important role in orthodontic treatment. This study was conducted on females as most girls have their growth spurt at a younger age than boys do, so their demand to facial esthetics, especially those who have residual growth of mandible producing class III effect, requires full understanding to smile features helping in diagnosis and treatment planning for maximum patient satisfaction.

MATERIALS AND METHODS:

This study was conducted on 30 skeletal Class III and Class I female adults (18–30 years old) who were divided equally into two groups comprising 15 each. Two frontal digital photographs were taken for each subject, one at rest and the other in the posed smile position. Photographs were taken for each subject in the natural head position by a Canon EOS 1200 D camera set on a tripod at a distance of 1.5 m. The incisogingival height of the right maxillary central incisor was clinically measured using a vernier caliper to the nearest 0.1 mm. Photographs were uploaded on Photoshop software for standardization and then uploaded on the Digital Smile Design software (DSD) where the actual incisogingival height of the central incisor was used for automatic calibration. Esthetic components at rest and on smiling were measured for both groups; all linear variables were measured to the nearest 0.1 mm.

RESULTS:

Class III females tended to have wider smile widths, less gingival display, longer chin heights, shorter lower vertical dimensions, and a higher percentage of nonconsonant and flat smile arcs than Class I subjects.

CONCLUSIONS:

The components of the smile should be considered as a guide to help in planning and designing the mechanics during comprehensive orthodontic treatment.

Smile esthetics: Impact of variations in the vertical and horizontal dimensions of the maxillary lateral incisors

OBJECTIVE

The purpose of this study was to determine the perception of trained dental professionals and laypersons toward the esthetic impact of variations in the vertical position, width, and gingival height of the maxillary lateral incisor.

MATERIALS AND METHODS

The present study analyzed the perspective of smile photographs by dental professionals such as "fifty orthodontics and fifty general dental practitioners (GDPs)" as well as fifty laypersons, consisting of an equal number of male and female participants. Photographs edited to depict alteration of golden proportion, incisal length, and gingival height of lateral incisor. SPSS software was used to analyze the data and determine the significant difference within all the participants, at 0.05% level (95% confidence interval).

RESULTS

There was no significant difference in ranking between the genders. Golden proportion of 62%-67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Regarding gingival display, corrected height of -0.5 and -1 mm received highest ranking from all the three groups. In case of lateral incisal length, -0.5 mm was ranked highest by laypersons, in contrast to -1 mm by orthodontists and GDPs.

CONCLUSION

Specific differences were observed in the ranking of smile esthetics by health-care professionals and laypersons. Golden proportion of 62% and 67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Corrected gingival height of -0.5 and -1 mm received highest ranking from all the three groups. In case of lateral incisal length, -0.5 mm was ranked highest by laypersons, in contrast to -1 mm by orthodontists and GDPs.

Esthetic impact of gingival plastic surgery from the dentistry students' perspective

Objective:

The aim of the this study was to evaluate the perception of smile esthetics and alterations in cases of gingival plastic surgery for correction of a gummy smile, by means of alterations in smile photograph among dentistry degree students.

Materials and Methods:

A frontal smile photograph of a 40-year-old woman having normal occlusion was used with diverse compositions of gingival exposure level and crown length of maxillary teeth. The eight photographs were evaluated by 216 dentistry students in five class groups (1^st, 2^nd, 3^rd, 4^th and 5^th classes).

Results:

The results revealed that almost all of the class’ students perceived differences between images, additionally, the highest percentage of students that answered “no difference” was 12% at 1^st class’ students. 1^st and 2^nd class’ students most liked photograph which is 2.5 mm gingival display and 3^rd class students liked two different photographs which are 2.5 mm gingival display and 2 mm gingival display whereas 4^th class students preferred two different photographs which are 1.5 mm gingival display and 1 mm gingival display, 5^th class students preferred photograph which is 1.5 mm gingival display as the most.

Conclusion:

Esthetic perception of smile improve as a student passes to higher study classes in terms of gingival exposure. The harmonious display of gingiva exhibits an important effect in the smile esthetics rather than reduced or excessive display.