"Gingival (gummy) smile" -
diagnostic value and treatment
with botulinum neurotoxin
M.I. Soykher1, O.R. Orlova 1, M.G. Soyher1, L.R. Mingazova 1, EM Soyher2
Summary: Smiling is an important human facial expression of nonverbal communication.
Smile aesthetics represent a target for minimally invasive procedures such as botulinum neurotoxin injections for improvement and correction. We present the pathogenesis, diagnostic significance and treatment options of the so-called gummy smile. Gummy smile aesthetic correction is a multidisciplinary task.
Introduction: Today, more and more people are trying to understand [4, 14] in their life motto: "everything in a human being should be perfect" [15]. Mostly, we pay a lot of attention to our appearance and special importance is given to our face [5, 6]. Each unique human face has significant personal significance for each of us. Smile and lips are the main factors in the aesthetic perception of the face. Many authors such as Pererverzev (1978), Khoroshilkina (1979), Persin (1988), Polma L (1996, 2010), Arsemima (1998), Ricketts (1981), Bishara (1985), Bacceti (2000), Sarver (2001) and Ackerman (2004) have made contributions to the study of facial aesthetics. The motivation of patients for dental treatment in recent times is increasingly aimed at obtaining an aesthetic result. The analysis of the reasons why patients turn to dentists showed [7, 11], that 23.0% of patients want to improve the aesthetics of the appearance of the teeth, 71.2% of orthodontic patients want to improve the aesthetics of the face and teeth, such as the reconstruction of the rows of teeth. In recent years, facial aesthetics related to the smile area is particularly important. The smile area is a functional and aesthetically important area. It consists of macro- (facial and labial) and micro- (gingival and dental crown) different parameters [3].
The process of forming a smile is divided into 4 stages:
1st stage – the lips are closed
2. phase - the lips are open (semi-open)
3. scene - natural smile (three quarters of open lips)
4. scene – wide smile.
Currently, smile analysis is the key to the diagnosis and rehabilitation planning of dental patients. A smile can destroy or emphasize the harmony of the face. Therefore, an attractive smile becomes an important indicator of successful dental rehabilitation. What is the "perfect smile"? Are there any clear criteria for this concept? We can easily distinguish which smile is beautiful, but it is difficult for us to describe the characteristics that create it. Many researches on the problem of facial aesthetics in young patients show the presence of "smiling gums" in 10-15% of cases. In fact, the aesthetics of the smile depends on: the parameters of the relationship between the teeth and gums, the relationship between the parameters of the teeth and lips and their harmonious integration with the components of the face. Mimicry muscles are the main component of a smile [32, 33]. Approximately 7% of men and 14% of women have excessive visualization of the gums when smiling.
Gingival smile - is a type of tissue structure of the oral cavity, where the smile appears during the displacement of the upper lip that exposes the gums. The main evaluation parameter is the height of the oval face. The height of the middle part of the face should be equal to the height of the lower part in a relaxed state. A "gingival smile" can be a symptom of a disorder in the structures of the facial skeleton and hyperactive facial muscles (Fig. 1).
The anatomical landmark of the middle part of the face is the glabella - the most prominent point of the frontal bone between the superciliary arches and the lower point of the nasal septum. The lower part is measured from the end of the nasal septum to the lowest point of the soft tissues of the mandible, i.e. the lower edge of the chin. In this case, for women, maxillary central incisors are usually visualized 3–4 mm (Fig. 2b), and 2 mm less for men. A short or hyperactive upper lip is one of the factors of formation. Usually, with a wide smile, the 10-11 mm long tooth crowns are fully visible. However, for the patient with a hyperactive upper lip, these parameters can increase 1.5-2 times (Fig. 3). In addition, the excessive extension of the maxillary front teeth [20] leads to a displacement of the gingiva together with the lower bone, and their lower position leads to the appearance of a "gingival smile". The reason for the excessive visualization of the gingiva may also be an increase in the height of the mandible, which makes the lower part of the face longer compared to the middle part [16, 18, 22]. According to Jiao Wei et