What causes a crooked mouth when smiling?

The phenomenon of a crooked mouth when smiling may stem from various contributing factors. Individual factors such as habitual smiling patterns and tooth alignment can affect the coordinated movement of the facial muscles. Psychological factors, including emotional states like tension and anxiety, may also cause muscle tightness, leading to asymmetry in the mouth during smiling. Facial paralysis, a common neurological condition, often results in facial muscle weakness or paralysis and is a frequent cause of lopsided smiles. Congenital developmental abnormalities, such as irregularities in the jawbone or facial muscles, can also result in a crooked mouth when smiling.

Cerebrovascular diseases, such as cerebral infarction, may impair the function of facial nerves and consequently lead to an uneven smile. In response to these underlying causes, multiple treatment approaches are available. These include daily adjustments such as modifying smiling habits and relaxing the mind, physical therapies like facial muscle exercises and acupuncture, and medical treatments such as neurotrophic drugs for facial paralysis. If symptoms worsen, prompt medical attention is recommended.