Both "Zähne putzen" and "Zähne bürsten" are commonly used in German to refer to the act of brushing teeth. "Zähne putzen" directly translates to "cleaning teeth," while "Zähne bürsten" translates to "brushing teeth." Both phrases are widely understood and used interchangeably in everyday language. **

Good oral hygiene involves maintaining a routine of daily practices to keep your mouth clean and healthy. This includes brushing your teeth at least twice a day with fluoride toothpaste, flossing daily to remove plaque and food particles between teeth, and using mouthwash to kill bacteria. Regular dental check-ups and cleanings are also important to prevent and detect any oral health issues early on. Additionally, avoiding tobacco products and maintaining a balanced diet can contribute to good oral hygiene. **

Private health insurance typically does not cover teeth whitening procedures, as they are considered to be cosmetic treatments rather than medically necessary. However, some dental insurance plans may offer coverage for teeth whitening as part of a broader dental care package. It's important to check with your insurance provider to understand what specific dental treatments are covered under your plan. **

A sly smile typically conveys a sense of cunning or deviousness, often suggesting that the person is up to something secretive or manipulative. On the other hand, a mischievous smile is more playful and light-hearted, indicating a sense of fun or harmless mischief. While both smiles may involve a hint of mischief, a sly smile tends to have a more negative or secretive connotation compared to a mischievous smile. **

A mischievous smile is typically playful and lighthearted, often indicating a sense of fun or harmless mischief. On the other hand, a sly smile is more cunning and secretive, suggesting a hidden agenda or a sense of trickery. While both smiles may convey a sense of amusement, a mischievous smile is more innocent and straightforward, while a sly smile carries a sense of deception or manipulation. **

Bleaching refers to the process of using chemicals like hydrogen peroxide to whiten teeth beyond their natural color, often done by a dentist. Cosmetic teeth whitening, on the other hand, typically involves using over-the-counter products or professional treatments to remove surface stains and brighten the teeth without altering their natural color. While both methods aim to whiten teeth, bleaching is more intensive and can achieve more dramatic results compared to cosmetic whitening. **

Personal hygiene refers to the practices and habits that individuals maintain to keep themselves clean and healthy, such as bathing, brushing teeth, and washing hands. Workplace hygiene, on the other hand, refers to the cleanliness and sanitation practices that are maintained in a work environment to ensure the health and safety of employees. This includes regular cleaning of workspaces, proper disposal of waste, and maintaining a hygienic environment to prevent the spread of germs and diseases. While personal hygiene focuses on individual cleanliness, workplace hygiene is about maintaining a clean and safe environment for all employees. **

Based on the information provided, it is not possible to determine if the friend has poor oral hygiene. The fact that the friend has not visited a dentist in several years could indicate poor oral hygiene, but it could also be due to other reasons such as fear of the dentist, financial constraints, or simply not feeling the need to go. Without more information, it would be unfair to make assumptions about the friend's oral hygiene. **