The exam of the oral structures must be performed in all patients in a complete and orderly fashion, under good illumination, whether natural or artificial, providing oneself with gauze and a tongue depressor, and making sure one one inspects and palpates: lips, buccal mucosa, hard and soft palate, oropharynx, floor of the mouth, tongue, gingivae and teeth. This serves to evaluate the state of health of these structures and serves to “see” if there are any incipient primary or secondary lesions which characterize any condition or illness which the patient has, as well as to interpret and correctly diagnose such lesions.
The lips are the anteriormost part of the mouth; the skin surrounding them ends at a slightly raised line which contorns them and is called the mucocutaneous or vermillion border, from there to the mucosal union we have a red zone also known as the labial semimucosa, a trait characteristic of humans. The union of upper and lower lips at the sides are the labial commisures.
Intraorally the lips are covered by a rose-colored, smooth, glossy, wet and thin mucosa. It extends to the bottom of the sulcus and at the midline we encounter a band of tissue which extends from the lips to the gingivae and is called the labial frenum
