Masseter hypertrophy (MH) is rare, asymptomatic condition with unexplained etiology. The main finding is unilateral or bilateral benign enlargement of masseter muscles, which results in a pronounced contour of the face and/or in the angle of the lower jaw, as well as the occurrence of asymmetry in unilateral hypertrophy.
Surgical resection of the masseter was a conventional method in the past for asymmetric edema treatment above the shoulder and the angle of the lower jaw, after unsuccessful altering of the vertical dimension, dental aligners, tranquilizers, etc. An effective alternative is injecting locally small doses of botulin toxin type A in the masseter. The toxin prevents the release of acetylcholine, causing presynaptic neuromuscular blockage. This way the muscles could be selectively weakened and after local paralysis muscle atrophy is observed. This technique ensures predictable result and it is an alternative conservative method for treating this type facial asymmetry. Another conservative way for treating MH is radio frequency electrocoagulation. The presence of MH after dental treatment requires specialized intervention of specialists and application of contemporary non-invasive interventions with predictable results.
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