Flossing is a fundamental practice in maintaining oral health, designed to remove plaque and food debris from areas a toothbrush cannot effectively reach. The answer to whether you should floss behind your last molar is yes, as this step is necessary for comprehensive plaque removal throughout the entire dental arch. Skipping this final surface leaves a significant portion of the tooth vulnerable to bacterial buildup.
The Critical Distal Surface: Why Cleaning is Essential
The last molar has a unique surface called the distal surface, which is the side facing the throat, away from the midline of the dental arch. This area is susceptible to plaque accumulation because its location makes it difficult to reach with a standard toothbrush. If left undisturbed daily, the distal surface often becomes a breeding ground for bacteria.
Neglecting this area increases the risk of localized dental issues. When plaque, a sticky film of bacteria, is not removed, it can lead to gingivitis, the initial stage of gum disease characterized by inflamed, red, or bleeding gums. Persistent accumulation of bacteria on this surface can also cause a specific type of decay known as distal caries. This decay is difficult for a dentist to detect early and treat because of the tooth’s position, underscoring the importance of preventative cleaning.
Mastering the Technique for the Last Molar
Proper technique is necessary to effectively clean the distal surface of the last molar using traditional string floss. Begin with a section of floss about 18 inches long, wrapping most of it around your middle fingers. Leave a small, manageable length taut between your index fingers and thumbs. This allows for precise control of the floss in the tight space at the back of the mouth.
Gently guide the floss back until it reaches the final tooth in the arch. Instead of sliding it between teeth, you must curve the floss into a “C” shape, wrapping it around the entire back contour of the molar. This C-shape ensures the floss contacts the entire surface, even slightly below the gum line, without snapping against the tissue.
Once the floss is curved around the back wall of the tooth, use a gentle up-and-down motion to scrape away accumulated plaque. You should repeat this motion several times on the distal surface before removing the floss. Using a clean section of floss for each tooth surface prevents the transfer of bacteria and debris throughout the mouth.
Specialized Tools for Hard-to-Reach Areas
For individuals who find the manual dexterity required for string flossing difficult, several alternative tools can simplify the process. Floss picks are a common option, featuring a small piece of floss pre-mounted on a plastic handle. The long handle and pre-tensioned floss make it easier to navigate around the cheek and reach the terminal distal surface.
Water flossers, which use a pressurized stream of water, are an effective alternative for cleaning the back of the molars. The pulsating jet of water reaches below the gum line and into the tight space behind the last tooth, flushing away debris and plaque. These devices are especially helpful for those with limited mobility or dental work that makes traditional flossing challenging. Interdental brushes, which are small, cone-shaped brushes, can be used if there is sufficient space behind the last molar. They provide a scrubbing action that cleans the contour of the tooth surface.