The wisdom teeth, or third molars, are the final set of teeth to emerge into the mouth, typically appearing between the late teenage years and early twenties. Many people encounter problems because the jaw often lacks sufficient space for these late arrivals. When a third molar cannot fully erupt, it creates conditions favorable for infection. This specific infection, known as pericoronitis, involves the inflammation and swelling of the gum tissue surrounding the partially emerged tooth.
Identifying the Visible and Physical Signs
The most noticeable sign of an infected wisdom tooth is the localized swelling of the gum tissue in the back of the mouth. This tissue, which partially covers the erupting molar, becomes inflamed, red, and puffy. This swelling is a result of the body’s immune response fighting the bacteria trapped in the area.
Visual inspection may also reveal the presence of pus, a thick, yellowish or whitish fluid draining from beneath the swollen gum flap. This discharge is a collection of dead white blood cells, bacteria, and tissue debris, confirming an active bacterial infection. The drainage of this pus often leads to a persistent, foul or metallic taste in the mouth, accompanied by bad breath, which cannot be resolved by brushing or mouthwash.
The sensory signs of the infection are often a throbbing, debilitating pain localized to the area of the back molar. This discomfort can radiate outward, extending toward the ear, the jawbone, or even the throat. The pain is constant and escalates when chewing or applying pressure to the affected side of the mouth.
A severe physical manifestation of the infection is trismus, which describes a limited ability to open the mouth fully. The muscles and tissues in the jaw become inflamed and spasm, making it difficult and painful to speak, eat, or perform routine oral hygiene. This inability to open the jaw suggests deeper muscular involvement.
Systemic symptoms indicate that the infection is affecting the body more broadly. These include a low-grade fever as the immune system attempts to combat the infection. Furthermore, the lymph nodes beneath the jaw and in the neck may become tender and swollen. These nodes filter the infectious material draining from the infected site.
The Root Causes of Wisdom Tooth Infection
The problem begins with the structural positioning of the wisdom teeth, which are the last teeth to develop within the jawbone. When the jaw is too small, the third molar becomes impacted, meaning it is stuck against the adjacent molar or partially lodged within the bone. This impaction prevents the tooth from emerging completely, leading to a state of partial eruption.
A partially erupted wisdom tooth leaves a section of the crown covered by a flap of gum tissue called the operculum. This flap creates a breeding ground for infection. The space between the tooth surface and the overlying gum tissue is impossible to clean effectively with a toothbrush or floss.
Food particles, plaque, and oral bacteria accumulate beneath the operculum, sheltered from normal cleaning actions. This trapped debris decomposes and allows bacteria, such as Streptococcus and Actinomyces, to multiply. The resulting bacterial overgrowth triggers the inflammatory response, leading to the localized infection known as pericoronitis.
The continuous presence of this bacterial reservoir means the infection often recurs if the underlying anatomical issue is not resolved. Even if acute symptoms temporarily subside, the physical structure remains unchanged, allowing debris to re-accumulate easily. This cycle of inflammation and infection can lead to chronic issues and damage to nearby teeth and bone over time.
Necessary Medical Intervention
Once a wisdom tooth infection is identified, professional medical intervention is required to manage the acute phase and prevent complications. The initial step involves a thorough cleaning and irrigation of the infected area by a dentist or oral surgeon. This process flushes the space under the gum flap with a sterile solution to remove trapped debris and reduce the bacterial load.
If an abscess (a localized collection of pus) has formed beneath the gum tissue, the dental professional may need to drain it. Draining the infection releases pressure and removes a source of bacteria, providing immediate symptomatic relief. This step is often performed before any definitive surgical procedure is scheduled.
To control the spread of the infection and prepare the site for long-term treatment, antibiotic therapy is necessary. Commonly prescribed antibiotics include amoxicillin or amoxicillin-clavulanic acid, taken for a course of five to seven days. The antibiotics work systemically to reduce the number of bacteria, especially when the infection has caused facial swelling or lymph node involvement.
The use of antibiotics only treats the active infection and does not address the underlying structural cause. The definitive solution to prevent the infection from returning is the surgical extraction of the problematic wisdom tooth. Removing the tooth eliminates the operculum and the deep pocket where bacteria and food debris accumulate.
Surgical removal is recommended when the tooth is clearly impacted or growing in a position that will lead to recurring infections. While minor gum flap removal may be an option in select cases, extraction is the most reliable method for long-term resolution of pericoronitis. A dental professional determines the best course of action based on X-rays and the severity of the impaction.