What are the causes of swelling and pain in the gums at the back of the mouth?
Aug 01, 2022
Source: Cainiu Health
Dr. Zhang Liwen
Introduction
The most likely cause of swelling and pain in the gums of the posterior teeth is pericoronitis—commonly known as “vertical tooth”—referring to inflammation around a partially erupted third molar (wisdom tooth) located distal to the second molar. As wisdom teeth are the last teeth to erupt, and given modern diets rich in soft, refined foods coupled with evolutionary reduction in alveolar bone volume, there is often insufficient space for proper eruption. Consequently, wisdom teeth may become impacted, and their partially exposed position makes them difficult to clean effectively during routine brushing.
Many people experience gum swelling and pain. When gums become swollen and painful, discomfort may occur not only during eating but also—especially in severe cases—while drinking water or even opening the mouth. So, what causes swelling and pain in the gums at the back of the mouth?
What Causes Swelling and Pain in the Back Gums?
The most common cause of swelling and pain in the gums behind the molars is pericoronitis—often referred to as “vertical tooth” inflammation—occurring around impacted wisdom teeth (third molars), which erupt behind the second molars. As wisdom teeth are the last teeth to emerge, modern dietary habits (involving softer, more refined foods) and evolutionary reduction in jawbone size often leave insufficient space for their proper eruption. Consequently, wisdom teeth may become partially or fully impacted, making them difficult to clean effectively during routine brushing. Food debris trapped around these teeth undergoes bacterial fermentation in the warm, moist oral environment, leading to bacterial proliferation, gingivitis, gum swelling and pain, and—in severe cases—trismus (limited mouth opening). Initial management should focus on controlling the inflammation; once the gingival inflammation has resolved, surgical removal of the impacted wisdom tooth is typically recommended.
When experiencing pain in the posterior gums, patients may first try adjusting their work-rest schedule and diet, and rinsing the mouth with warm saline solution to see whether mild early-stage swelling and pain improve. However, if self-management fails to alleviate even mild gum swelling and pain, prompt consultation with a dental clinic is advised for professional cleaning and appropriate medication. Swelling and pain in the posterior gums most commonly stem from inflammation associated with wisdom teeth—particularly mandibular (lower) wisdom teeth. If swelling and pain occur along the distal (back) side of the lowermost molar, carefully examine whether a wisdom tooth is in the process of erupting.
Patients should avoid staying up late and, in terms of diet, steer clear of spicy or irritating foods. Instead, they should consume easily digestible foods and drink plenty of water. We hope this information proves helpful.
