Evaluation of Change in the Facial Profile and Aesthetics in Relation to Incisor Position in Both Maxillary and Mandibular Arches

Abstract

BackgroundThe orthodontist is often confronted with the need to predict soft tissue profile changes that may result from the orthodontic treatment. The problem arises because the contribution of many of the factors influencing the soft tissue profile still needs to be fully understood. The complexity of the problem is increased in growing patients in whom the post-treatment soft tissue profile is the result of both growth and orthodontic treatment. A primary motivation for seeking orthodontic treatment is a desire to improve dental and facial aesthetics. To achieve balance in the facial profile treated orthodontically, it is essential to identify the underlying skeletal hard tissue and soft tissue parameters. The present study evaluated the changes in facial profile and aesthetics in relation to incisor position. Materials and methodsSamples for this study consisted of pre-treatment lateral cephalograms of the Indian population (n = 450) having different incisor relationships. Subjects aged between 18 and 30 years were included. Angular and linear measurements were taken to analyse the incisor relationship with soft tissue parameters. ResultsThe majority (61.2%) of subjects belonged to the age group of 18-30 years. The overall female-to-male ratio in the study was 7:3. The parameter U1 to L1 was abnormal in 86.8% of subjects. Similarly, the parameters Sline upper lip (UL), S-line lower lip (LL), E-line UL, and E-line LL were found abnormal in 93.9%, 86.8%, 82.6%, and 70.1% of subjects, respectively. A significant agreement was found between U1 to L1 and E-line UL and U1 to L1 and E-line LL. ConclusionsThe present study concludes that facial aesthetics combines soft and hard tissue corrections, not just based on occlusal relationships but also considering facial harmony. Thus, the incisor relationship is an important asset and strongly correlates with other soft tissue and hard tissue parameters that improve facial aesthetics for the individual undergoing orthodontic treatment.

Network analysis of three-dimensional hard-soft tissue relationships in the lower 1/3 of the face: Skeletal Class I-normodivergent malocclusion versus Class II-hyperdivergent malocclusion

“…However, many previous studies [4,5,7,11,12,13,14] have analysed patients with different skeletal types as a whole when looking for the morphological mechanism of soft tissues or making predictions. This might be one of the reasons for their limited accuracy.…”

“…Previous studies concerning skeletal Class II hyperdivergent malocclusion have been carried out, most of which were two-dimensional (2D) analysis using lateral cephalograms [4,5,6,7,8,9,10,11,12,13,14]. Kasai K [4] reported that the vertical dimension of the lower facial height and the position of the lower incisors were associated with the thickness of the upper-lip vermilion and soft tissue B.…”

“…It is well known that the relationship between craniomaxillofacial (CMF) hard and soft tissues is very complicated. Previous studies used correlation analysis or multiple regression analysis [4,5,6,10,11,12,13,14] to learn the relationship between soft and hard tissues, but the overall relationship of the CMF system could not be explored or visualized. For now, the most advanced arti cial intelligence algorithm [7] for predicting soft tissue contour from hard tissue shape calculates only two line distances (the distance between labrale superius or labrale inferius to the esthetics plane), which essentially predicts the position of merely two points, and cannot re ect the complex soft tissue contour.…”

Novel Parameter in Pre-Surgical Orthodontic Preparation: A Retrospective Study on the Role of the Upper Incisor Position and a Morphological Evaluation of the Anterior Nasal Spine

“…It has already been stated that correct occlusion does not always equate to a desirable facial profile and orthodontic treatments solely adhering to cephalometric standard values may not necessarily fulfill aesthetic principles [14]. In the assessment of facial aesthetics, it is crucial not only to evaluate occlusion and dental alignment, but also to consider the relationship between the skeleton and soft tissue [15]. The soft tissue profile, including the nasolabial and labio-mental zones, has received significant attention in recent years [16].…”