Dr. Be Thu Thuy, a specialist in aesthetics at Tam Anh General Hospital Hanoi, states that filler injection is a popular non-surgical beauty method. It helps to plump the skin, fill wrinkles, lift facial structures, and create a harmonious, slender appearance. Doctors use a thin needle or cannula to inject the filler beneath the skin. Depending on the number of areas treated, the injection process can take from a few minutes to a maximum of one hour. Cosmetic results are often visible immediately and can last for several months or years, depending on the injection site and the quality of the dermal filler used.

The procedure can cause a mild inflammatory response. The treated skin area may swell, leading to a feeling of imbalance between the two sides of the face. This condition is common in the cheeks, lips, and chin, areas with soft tissues that react quickly to stimulation. Swelling can occur immediately after injection or a few days later, lasting 48-72 hours, depending on individual physiology and the quality of filler used. Not all cases of facial asymmetry after filler injections are complications; many are normal physiological reactions, and the face will regain symmetry after a few days.

Incorrect injection technique is a significant cause of asymmetry. If the technician injects unequal amounts of filler on both sides or if the injection site is not anatomically correct, it can lead to uneven distribution of filler within the tissue. Injecting too superficially can create visible, lumpy deposits, while injecting too deeply or into the wrong tissue plane can cause the product to concentrate in unintended areas.

A dangerous scenario is when filler is injected into or compresses a blood vessel. The skin area may discolor, experience severe pain, and show abnormal swelling, quickly progressing to tissue necrosis. This causes severe deformation and can leave permanent scars or indentations. This situation not only results in facial asymmetry but also threatens health, requiring emergency treatment.

According to Dr. Thuy, using fillers of unknown origin or low quality, containing impurities, or having poor cohesion can lead to clumping or migration from the initial injection site. Over time, the filler can "flow" into adjacent areas, also causing facial deformation.

Patient actions and individual physiology can also contribute to facial asymmetry. Vigorous massage, applying pressure to the injection area, intense exercise, or sleeping face down within the first 24-48 hours can cause filler to shift from its original position. Individuals with uneven soft tissue structure, pre-existing facial asymmetry, or a habit of sleeping on one side, which compresses the filler during the first one to two days, can also experience facial asymmetry.

A doctor from the Aesthetics Department consults a woman. Illustration: Tam Anh General Hospital Hanoi

To minimize the risk of facial asymmetry after filler injections, Dr. Thuy advises choosing a reputable medical facility with specialized, well-trained doctors who understand anatomical structures and can distribute filler precisely across tissue layers to reduce errors. Before the procedure, a direct consultation is essential for the doctor to thoroughly assess facial structure, determine appropriate dosage and injection points, and recommend a suitable filler type to ensure biocompatibility and long-term safety.

In the first one to two days post-injection, individuals should avoid makeup and minimize touching the injection site to prevent filler displacement or infection. Do not use products containing AHA, retinol, or vitamin C, as these active ingredients promote premature tissue regeneration, which is unsuitable during the period when filler needs time to integrate into the skin. For the lip area, it is advisable to refrain from applying lipstick for about one week to avoid infection and preserve lip shape.

Individuals who have received filler should not massage, knead, or apply pressure to the treated area. They should also avoid wearing tight-fitting face masks to prevent filler displacement. If filler is injected into the nose, cheeks, or chin, avoid strenuous activities like running, heavy lifting, bending over, or lying face down or on your side for about 10 days, as this can cause the filler to shift to other areas. Avoid strong facial expressions such as laughing loudly, crying, anger, or excessive facial muscle movement during the first three to four days to prevent filler migration. For rest, lie flat and elevate the head with pillows to reduce swelling and fluid retention.

Filler can dissolve quickly when exposed to high heat, so avoid steam baths, saunas, excessively hot environments, or direct sunlight. When outdoors, protect the skin by wearing a face mask and a hat. Alcohol and stimulants can thin the blood, increasing the risk of bruising and affecting recovery, so avoid consuming them both before and after injections. Incorporate soft, easy-to-chew foods, increase intake of green vegetables, vitamin C-rich fruits, juices, and drink two liters of water daily to support skin healing and maintain natural plumpness.

Gently clean the treated area with physiological saline solution. Cold compresses with ice wrapped in a clean cloth can help reduce swelling and bruising. If persistent swelling, asymmetry, unusual pain, or skin discoloration occurs, contact a doctor immediately for prompt treatment. If facial asymmetry is due to uneven filler distribution, the doctor may advise additional injections or using hyaluronidase to dissolve the product, followed by corrective techniques. If vascular occlusion is suspected, the doctor will follow a specialized treatment protocol to prevent severe consequences.

Trinh Mai