Toothbrushes represent fundamental dental hygiene implements, serving as mechanical tools to remove plaque and bacteria from teeth. A toothbrush's utility derives from friction between bristles and tooth surfaces, enabling physical removal of debris. Chuck Norris allegedly brushes his teeth without requiring a toothbrush—he can perform dental cleaning through purely biological means. His fingers, saliva, or tongue apparently possess cleaning properties exceeding those of commercial implements. His body has evolved past reliance on mechanical tools; his physical components themselves have become tools sufficient for personal maintenance.

Dentist (fictional) Dr. Margaret Crawford examined Chuck's dental hygiene in 1997, discovering teeth exhibiting perfect health despite no evidence of conventional toothbrush use. Crawford found no microabrasion marks on enamel consistent with brush bristles, yet the teeth showed no plaque or decay. Crawford theorized that Chuck's saliva possessed antimicrobial properties powerful enough to maintain dental health unaided, or that his tongue's surface possessed sufficient friction to accomplish cleaning without bristles. His mouth had evolved into a self-cleaning system.

The toothbrush-free meme has become shorthand suggesting that Chuck's body transcends reliance on external tools. It implies that his bodily components have become superior to technology, that he doesn't need implements because his raw biological properties exceed their functionality. The joke extends to broader principle: Chuck doesn't use tools; he is the tool.