Association of the nasolabial angle and lip length with the gingival and interdental smile line—A gender based evaluation

Abstract

Objective Proportionate existence of the lip framework and gingival scaffold have a critical role in smile esthetics. So, the present study was conducted to assess and correlate the nasolabial angle (NLA) and lip length (LL) with gingival smile line (GSL) and interdental smile line (ISL). Materials and methods One hundred and twenty periodontally healthy patients with an age group 20 to 40 years were equally divided based on gender into two groups. The parameters of NLA, LL, GSL, ISL, amount of midfacial gingiva, and interdental papilla display were recorded in the maxillary anterior sextant. Results The mean values of NLA and LL at rest and on smiling were found to be higher in males. Majority of study population exhibited Low GSL (LGSL) and High ISL (HISL). On correlation of LL with GSL, the difference in the mean values between males and females for LGSL were highly significant, for HGSL and Cupid's bow the values were significant. The mean values of midfacial gingiva and interdental papilla visible in females was greater than males. Conclusion The NLA and LL influence the quantum of gingival exhibit in maxillary anterior teeth with a definitive sexual dimorphism and this can be considered a valuable reference point in smile designing procedures. Clinical significance The quantum of gingival exhibit on smiling is an important feature in periodontal, implant, restorative, and smile designing procedures in patients possessing HGSL and HISL category of GSL and ISL. It is indicated that the lip length is correlated with the amount of gingival tissue display both in midfacial as well as interdental region and which needs to be considered by the clinician.

Effects of polymethyl methacrylate-based bone cement graft for treating excessive gingival display and its dimensional facial changes: 12-Month clinical study

“…A previous publication found a slightly higher nasolabial angle in patients with a gingival smile compared to participants without the condition. 31 The difference in values of NAR (96.68°) compared to NAS (86.03°) was 10.65° in females, 31 which is the reason why different analyses should be performed. During smile functioning, the dynamic position that the upper lip reaches causes musculature stretching, and consequent volumetric changes in lip and nose components of the nasolabial angle.…”

Lip position in the smile aesthetic: Literature review

“…The perception of beauty is subjective and depends on personal experience, the media [33], ethnicity [31,[34][35], culture [33][34][35], age [31,33,36], sex, or level of education [33,36]. However, according to Pham, T. & Nguyen P. [34], as well as Khan, M. et al [35] 31,35,37,38] the most frequent smile line is the average; followed by low and high. This may vary depending on the study location, in Saudi Arabia and Korea, the majority of the population agreed with the mid-smile line as the most frequent, followed by the high and low [39].…”