Botox injections may provide short-term relief to microstomia

Key takeaways:

• Patients saw a significant improvement in inter-incisor distance (5.8 ± 4 mm; P < .001) at 2-week follow-up.
• Although results were not sustained at the 3-month follow-up, patients were satisfied.

OnabotulinumtoxinA offers short-term relief to patients suffering from scleroderma/systemic sclerosis-induced microstomia, according to a study.

Scleroderma/systemic sclerosis (SSc) is an autoimmune connective tissue disease that causes severe complications. One such complication is microstomia, also known as reduced oral aperture (ROA).

“ROA ... is often understated despite its debilitating effects on physical appearance, phonation, mastication, dental hygiene and overall quality of life,” Cristian D. Gonzalez, MD, of the department of dermatology at The University of Texas Southwestern Medical Center, and colleagues wrote. “ROA may contribute to malnutrition which is responsible for 4% of SSc deaths.”

Current treatment options for ROA include physical therapy, surgery, topical steroids, phototherapy and immunosuppressive agents. In this prospective cohort study, researchers evaluated onabotulinumtoxinA (onabotA; Botox, Allergan Aesthetics) injections as a potential short-term treatment option for ROA in SSc.

Seventeen adult women with SSc who also had ROA received 16 units of onabotA total at eight different sites around the cutaneous lips.

Two weeks after treatment, results showed a significant improvement in inter-incisor distance with a mean difference improvement of 4.39 ± 4.3 mm in the total cohort and 5.8 ± 4 mm in responders (P < .001 for both). However, patients did not maintain these results and, instead, showed regression from these results at the 3-month follow-up.

Inter-labial distance saw a similar pattern, with significant improvements two weeks after treatments in the total cohort (7.8 ± 5.9 mm) and responders (10.7 ± 4.3 mm; P < .001 for both). Like the inter-incisor findings, these patterns did not persist at 3 months.

Additionally, inter-commissural distance was unchanged from baseline at 2 weeks or 3 months.

The were no changes in Mouth Handicap in Systemic Sclerosis Scale (MHISS) scores; however, 76% of patients reported high satisfaction with treatment and 53% reported “moderate-significant” observed improvement in symptoms.

The authors expressed that this discrepancy is “difficult to reconcile,” but may be because the MHISS assessment contains complicated terminology and questions about other symptoms other than ROA.

While onabotA does not offer long-term solutions, the authors report that it does have a positive short-term effect.

“OnabotA injection appears to offer substantial short-term improvement in oral aperture in patients with systemic sclerosis,” the authors wrote. “Patients also reported improvement in quality of life and high satisfaction with the treatment.”