Some smiles, however natural and spontaneous, can make the person behind them feel self-conscious. When smiling reveals more gingival tissue than what is perceived as harmonious, we refer to it as a gummy smile — a condition that affects roughly 10% of young adults and up to 26% of the general population, with a higher prevalence in women.
The good news for practitioners is that a surgical approach is not always necessary. In many cases, a well-structured injectable treatment plan delivers safe, predictable and highly satisfying outcomes.
When do we define a smile as “gummy”?
A gummy smile is clinically identified when a maximum voluntary smile exposes more than 2–3 mm of gingiva above the gingival margin of the upper incisors. A harmonious smile typically displays between 1 and 3 mm.
A practical classification based on the extent of gingival exposure helps guide therapeutic decisions: Grade I (mild), 2–4 mm; Grade II (moderate), 4–6 mm; and Grade III (severe), over 6 mm. This scale is indicative and does not replace a thorough etiological assessment, which remains the true cornerstone of clinical decision-making — two patients showing the same amount of gingiva may require entirely different treatment approaches.
Understanding the causes
Skeletal factors
The most common skeletal contributor is vertical maxillary excess, which causes the upper lip to rise higher than usual during smiling. Bony asymmetries may also be present, resulting in an uneven gummy smile. In more severe cases, orthognathic surgery remains the gold-standard treatment when the patient seeks a definitive correction of the skeletal component.
Dental factors
These include overeruption of the upper incisors, occlusal canting (one side displaying more gingiva than the other), clinically short-appearing crowns — whether due to actual size or altered passive eruption — and dentoalveolar protrusion, where excessively proclined teeth cause the lip to retract and expose more gingival tissue. Management typically involves orthodontics, periodontal surgery, or a combination of both.
Soft tissue factors
This is where injectable treatment with hyaluronic acid delivers its greatest clinical value. The most common scenarios include a short upper lip, upper lip hypermobility (excessive elevation from rest to maximum smile), gingival hyperplasia or inflammation — sometimes drug-induced — and altered passive eruption, where the gingiva has not fully migrated apically and still covers part of the anatomical crown.
Mechanical myomodulation with hyaluronic acid
When the predominant component is soft tissue-related, the infiltration of cross-linked hyaluronic acid at strategic points in the perioral area — perinasal region, pyriform area and upper lip semi-mucosa — creates a mechanical resistance against the contraction of the lip elevator muscles. The lip rises in a more controlled manner during smiling, reducing visible gingiva without compromising facial expression.
Compared to chemical myomodulation with neuromodulators, this approach offers complementary advantages: a volumising effect that harmonises the perioral frame, longer-lasting results (typically 9–12 months versus 3–6), full preservation of dynamic expressiveness, and complete reversibility with hyaluronidase if needed.
Treatment is not limited to a single injection point. It requires a comprehensive perioral assessment — evaluating lip projection, philtral column support, the relationship with the nasal alae, the nasolabial fold, and lip position both at rest and during movement — in order to design an infiltration plan that achieves a balanced, natural-looking smile.
Harmonie: three concentrations to personalise every case
Harmonie is IT Pharma’s cross-linked hyaluronic acid, designed to deliver harmonious and natural results. Its key differentiator is the availability of three concentrations, allowing practitioners to adapt gel density to each zone and each patient — from structural support in areas requiring greater firmness to a soft finish in highly mobile zones.
This versatility is particularly relevant in gummy smile treatment, where the practitioner works simultaneously across areas of different tissue depth and mechanical demand. Having three concentrations within the same product range ensures a cohesive final result.
A progressive approach for natural results
A thorough etiological diagnosis is non-negotiable before planning any injectable treatment. In many patients, factors from more than one category coexist, and a multidisciplinary approach strengthens overall outcomes. Hyaluronic acid treatment allows for progressive adjustments — a conservative first session with a follow-up at 2–4 weeks is usually the safest strategy — and it is essential that patients understand the goal is harmonisation, not the complete elimination of visible gingiva. A natural smile shows some gum tissue; the aim is for the amount to be perceived as balanced.
References
TMJ Clinic. (2024, December 2). Gummy smile: Why it happens and what the best treatment is [Sonrisa gingival: por qué se produce y cuál es el mejor tratamiento]. Barcelona TMJ Clinic.
Santana, L. (n.d.). Facial harmonization technique: 3 steps Harmonitation [Técnica de armonización facial: 3 steps Harmonitation]. IT Pharma.
Vitaldent. (2022, November 14). Gummy smile: What it is and what causes it [Sonrisa gingival o gummy smile. ¿Qué es y a qué se debe?]. Vitaldent.
Telletxea Iraola, M., López-Malla Matute, J., & Alía García, E. (2020). The three faces of gummy smile: A literature review [Las tres caras de la sonrisa gingival: Revisión bibliográfica]. Científica Dental, 17(2), 139–146.
