The human face is rarely perfectly symmetrical, and slight differences between the left and right sides are universal and completely normal. While inherent facial asymmetry often goes unnoticed, a noticeably puffier or swollen cheek signals a specific, localized issue. This unilateral swelling occurs when fluid or inflammatory material accumulates in the soft tissues of the cheek. The cause can range from simple, temporary factors to more serious underlying health conditions. Understanding the source of this localized puffiness is the first step in addressing the change in appearance.
Common, Non-Medical Explanations
In many cases, the observation of one puffy cheek is a temporary phenomenon not related to disease or infection. Natural anatomical variation can make one side appear fuller due to differences in fat pad distribution or muscle development. The muscles used for chewing, for example, can become slightly larger on the side used more frequently, creating a subtle difference in contour.
Temporary fluid retention is another frequent, non-medical cause that can be exacerbated by lifestyle factors. Consuming a diet high in sodium, for instance, can cause the body to retain water, and this fluid can accumulate unevenly in the face overnight. Similarly, the position one sleeps in can create a transient appearance of puffiness.
Sleeping consistently on one side can cause the cheek pressed against the pillow to experience temporary compression and a pooling of lymphatic fluid. This gravitational effect is usually most noticeable upon waking and tends to subside naturally within a few hours. These variations do not involve pain, redness, or warmth.
Dental and Oral Health Causes
One of the most common causes of localized cheek swelling originates in the oral cavity. A dental abscess is a serious bacterial infection that forms a pocket of pus, typically around the root of a tooth or in the gums. If left untreated, the inflammatory pus exerts pressure that extends outward into the soft tissue of the face, manifesting as cheek puffiness.
An impacted wisdom tooth is another frequent source of localized inflammation, especially when it is partially erupted and the overlying gum tissue becomes infected, a condition called pericoronitis. Food debris and bacteria can become trapped beneath the flap of gum, leading to swelling and pain that radiates into the adjacent cheek and jawline. In these dental scenarios, the swelling is often accompanied by severe, throbbing pain, sensitivity to temperature, and sometimes a foul taste in the mouth.
An untreated infection can quickly spread from the tooth socket into the facial tissues. This progression is concerning because the infection from a dental abscess can track through fascial planes. Swift intervention from a dentist is required to drain the pus and eliminate the source of the bacteria.
Infectious and Glandular Conditions
Puffiness in one cheek can also be a sign of infection or inflammation in the soft tissues or nearby glands, distinct from dental structures. Cellulitis is a bacterial skin infection that occurs when bacteria enter through a break in the skin, causing the skin to become red, tender, and warm to the touch, with the underlying cheek becoming visibly swollen. This type of infection can rapidly spread and requires prompt treatment with antibiotics to prevent systemic illness.
The salivary glands, particularly the parotid gland located just in front of the ear and extending over the cheek, can also be a source of unilateral swelling. Conditions like sialadenitis, an infection of the salivary gland, or the presence of a salivary stone (sialolithiasis) can cause the gland to become blocked and inflamed. Swelling from a blocked salivary gland may worsen when eating, as the gland attempts to produce saliva, which then cannot pass through the duct.
Sinusitis, or a sinus infection, is another possible cause, especially when the maxillary sinuses located behind the cheeks are involved. The inflammation and pressure from mucus buildup within these cavities can sometimes cause referred swelling or puffiness in the overlying cheek area. Viral infections, such as mumps, can also cause a characteristic unilateral or bilateral swelling of the parotid salivary glands.
Identifying When Medical Attention is Needed
While some cheek puffiness is harmless and resolves on its own, certain accompanying symptoms indicate the need for prompt medical evaluation. Any swelling that appears suddenly, is severe, or is associated with intense, worsening pain should be assessed immediately. The presence of a fever, along with localized warmth and redness, suggests an ongoing bacterial process like cellulitis or a spreading abscess. Any indication that the swelling is starting to affect the throat or airway demands emergency attention. Difficulty swallowing, changes in voice, or shortness of breath are signs that the swelling is progressing dangerously into deeper structures of the neck.
Persistent or non-resolving puffiness, even without severe symptoms, warrants a consultation with a physician or dentist. This consultation is necessary to identify the underlying cause and prevent potential complications.