Commentary on: Individual Factors of Botulinum Type A in Treatment of Gummy Smile: A Prospective Study

Neuromodulator Injection for Gummy Smile

SUMMARY

Neuromodulators have become a treatment of choice for the management of excess gingival show, or "gummy smile." There have been many proposed algorithms for the optimal placement and dosage of neuromodulator to inject in these locations. The authors aim to clarify these points and provide surgeons with a reliable way to manage the gummy smile that results from hyperactive muscles of the midface.

Botulinum Toxin A in the Management of a Gummy Smile: A Clinical Controlled Preliminary Study

BACKGROUND

Botulinum toxin type A (BTX-A) is recent technique for the treatment of gummy smile.

OBJECTIVES

The aim of this randomized controlled preliminary clinical trial was to evaluate the effects of BTX-A on excessive gingiva display (EGD) reduction, muscle activity, and patient satisfaction at 2, 8, 12, 16, 21, and 25 weeks.

METHODS

Group 1 (G1) received 4 points of BTX-A application (2 U/point) for relaxation of the levator labii superioris alaeque nasi and levator labii superioris muscles; Group 2 (G2) received 2 points of BTX-A (2 U/point) for relaxation of only the levator labii superioris alaeque nasi muscle.

RESULTS

A high dropout of patients from follow-up sessions occurred. Therefore, because of this data limitation, the results were considered a preliminary outcome. At 2 weeks, there was a significant difference between baseline regarding the reduction of EGD in G1 and G2, reduction in muscle activity in G1, and increased satisfaction in G1 and G2. At 2 weeks, there was no difference between the 2 groups. Statistically significant EGD reduction was maintained until 16 weeks in G2 and 25 weeks in G1. After 14 days there was a gradual recovery of muscle activity in both groups until recovery of baseline values by 25 weeks. Patients' satisfaction with treatment lasted 21 weeks in G1 and 16 weeks in G2.

CONCLUSIONS

Increasing the number of BTX-A injection points resulted in a prolonged effect regarding EGD reduction and patient satisfaction but did not increase the intensity of the outcome. However, due to the high dropout of patients, this is a preliminary conclusion and further studies are necessary to confirm these results.

LEVEL OF EVIDENCE: 2