Is it normal for floss to go under your gums
Floss may pass slightly under the gum edge, but force, persistent bleeding, pain, or a deep gap needs examination.
The short answer
Floss should pass slightly under the gum edge into the shallow gingival sulcus, but forceful entry, persistent bleeding, pain, or a deep gap needs an examination.

What is the direct answer?
What does this question mean?
The gum forms a cuff around each tooth, with a small sulcus between the tooth surface and the gingival margin. Proper flossing follows the tooth curve and cleans this space gently; it should not be snapped downward or pushed deeply into tissue.
What can you do next?
Use clean floss, guide it between the teeth with a gentle sawing motion, then curve it into a C shape against each tooth and slide it just below the gum margin. Use an interdental brush or water flosser if a dentist recommends one for your spaces.
When should you seek dental care?
Book an examination for repeated bleeding, tenderness, pus, bad breath, gum recession, or a space where floss drops unusually far. Sudden pain or swelling needs prompt assessment.
What should you ask the dentist?
Ask whether the bleeding reflects plaque-related gingivitis, a periodontal pocket, trauma, or another cause. Ask which cleaning aid fits your contact points and gum shape.
Frequently asked questions
Why does my floss smell?
Odor can come from plaque, trapped food, or inflamed gum tissue and should improve only when the cause is cleaned and treated.
Should I stop flossing when gums bleed?
Clean gently and arrange an assessment if bleeding continues, because avoiding the area can leave plaque undisturbed.
