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Layperson's Esthetic Preference to the Presence or Absence of the Interdental Papillae in the Low Smile Line: A
Mark N Hochman1, Stephen J Chu2, Bruno Pereira da Silva3
1Stony Brook School of Dental Medicine, Private Practice: Periodontics, Implant Dentistry and Orthodontics, New York, New York.
Purpose:
To determine the layperson's esthetic preference to the visual display (presence) or lack thereof (absence) of the interdental papillae during minimum smiling or the low smile line patient type.
Materials And Methods:
Two hundred lay-people were shown three-paired smile images indicative of a low gingival smile line patient type in which the vermillion border of the maxillary lip covered the mid-facial gingiva of the anterior teeth. The three images differed only with respect to [1] presence of interdental papillae, [2] absence of the interdental papilla ("black triangle"), or [3] absence of the interdental papillae (replaced with a long restorative contact area). The three images were paired in multiple groupings; group-1 consisted of a comparison of the presence of interdental papillae vs the lack of the interdental papillae "black triangle," group-2 compared the long restorative contact compared to the presence of the interdental papillae and Group-3 compared the long restorative contact replacing a missing papilla to the absence of the interdental papillae "black triangle." The comparisons were designed to determine the subjective preference of lay individuals between these groupings.
Results:
Ninety-eight percent of lay-people demonstrated a preference to the presence of the interdental papillae in the smile (image 1) when compared to its absence ("black triangle"; image 2) with a low smile line. Seventy percent preferred the visual display of the interdental papillae, that is, pink tissues (image 1), compared to the absence of the interdental papillae replaced with a long contact area (image 3), that is, white restorative materials, when viewing a low gingival smile line. And when comparing the absence of the interdental papillae "black triangle" to a long contact area, 92% of lay-people preferred a long contact area vs the absence of the interdental papillae with a "black triangle" with a low smile line.
Conclusions:
The visual display [presence] of the interdental papillae, that is, pink tissues, is notably preferred to the absence of the interdental papillae when replaced by either a "black triangle" or long contact area in the commonly known low smile line. This emphasizes the need to assess the Interdental Smile Line (ie, visual display of interdental papillae during smiling) in all patients and the importance to preserve and/or re-establishment of the interdental papillae, that is, pink tissues, even in patients with a low smile line.
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