The oral cavity is the first component of the digestive tract, which is delimited by the lips anteriorly and the oropharynx posteriorly. The oral cavity functions as a protective barrier and is an essential component for speech and swallowing, mastication, digestion, and taste sensation.
The oral examination comprises a uniform and consistent inspection of the head and neck and an intraoral evaluation of the hard and soft tissues (see the images below) in conjunction with a thorough medical and dental history. The entire mouth should be inspected regardless of the patient’s chief complaint and reasons for the visit.
Good patient’s history and careful examination are important to establish the correct diagnosis and provide appropriate treatment.
The physical examination begins with an extraoral examination to identify possible lesions (such as rash, erythema, and pigmentation), swelling or facial asymmetry. The head and neck should be palpated to identify any tenderness, masses and lymphadenopathy. All muscles of mastication and temporomandibular joint should be palpated for tenderness; patients should be asked to open and close the mouth multiple times to evaluate any limited opening, deviations or asymmetries. The cranial nerve examination should be performed to assess possible neurosensory and neuromuscular deficits.
A good light source is fundamental for a good intraoral examination. Any intraoral lesion should be described with respect to size, extent, thickness, color, texture, consistency, and tenderness.
Major salivary gland should be palpated and milked to assess salivary gland duct orifices patency and salivary flow and to evaluate the quality of saliva (e.g., frothy versus serous). In a healthy individual unstimulated whole salivary flow rate ranges 0.3–0.4 mL/min, while chewing-stimulated whole salivary flow is 1.5–2.0 mL/min.
Teeth should be examined to evaluate possible dental decays, fractures, mobility, defects in restorations, gingival recession and bone loss with inspection, palpation and percussion.
The hard palatal mucosa is characterized by keratinized epithelium and covered by a series of fibrous ridges or rugae. The mucosa overlays several minor salivary glands.
The lingual frenum is the primary soft tissue attachment of the tongue to the floor of the mouth. Over-attachment of the frenum may result in speech impediments.
See Clues in the Oral Cavity: Are You Missing the Diagnosis?, a Critical Images slideshow, to help identify the causes of abnormalities of the oral cavity.
Oral diseases can be characterized in different groups:
Autoimmune and immune mediated
A thorough medical, pharmacological and oral examination will guide the clinician to a correct diagnosis. When the clinical diagnosis of an oral lesion cannot be confirmed with its signs and symptoms, a biopsy of the oral soft tissues with an histopathological examination is warranted.
Intraoral photography with digital camera should be used to document mucosal lesions and evaluate the progression of the disease and responses to therapy. This typically requires 35-mm single lens reflex cameras with macro lens and ring flash attachment. Several models are available for intraoral photos.
The oral cavity is oval shaped and is separated into the oral vestibule and the oral cavity proper. It is bound by the lips anteriorly, the buccal mucosae laterally, the floor of the mouth inferiorly, the oropharynx posteriorly, and the palate superiorly. The oropharynx begins superiorly at the junction between the hard palate and the soft palate, and inferiorly behind the circumvallate papillae of the tongue. The bony base of the oral cavity is represented by the maxillary and mandibular bones. The oral cavity includes the lips (vermillion and labial mucosa), buccal mucosa, floor of the mouth, tongue, hard and soft palate, gingivae, retromolar trigone and teeth.