Chapter 17: Oral Pathology Study Notes

Chapter 17: Oral Pathology

Learning Objectives

  • Introduction to Oral Pathologies

    • Pronounce, define, and spell the key terms.

    • Describe oral pathology in dentistry.

    • Summarize the role of the dental assistant in understanding oral pathology.

  • Making a Diagnosis

    • Summarize the steps when making a diagnosis:

    • Collect historical information when suspicious lesions are noticed.

    • Describe clinical appearances examined for diagnosis.

    • Describe oral conditions identified by radiographic images.

    • List the rationale to biopsy a lesion.

    • Explain the importance of laboratory testing of oral infections.

    • State the use of certain medications for oral lesions.

    • Describe the rationale for surgical diagnosis.

    • Recall the importance of using differential diagnosis.

  • Inflammation

    • Differentiate between acute and chronic inflammation.

    • List the signs of inflammation.

    • Discuss the importance of identifying different types of oral lesions.

    • Classify lesions based on their position relative to the mucosal surface:

    • Below the mucosal surface

    • Above the mucosal surface

    • Even with the mucosal surface

    • Raised or flat lesions

  • Irregularities and Diseases of Oral Soft Tissues

    • Describe the appearance and conditions of the following:

    • Leukoplakia

    • Lichen planus

    • Candidiasis

    • Aphthous ulcers

    • Cellulitis

Definition of Oral Pathology

  • Oral Pathology: The study of diseases in the oral cavity.

    • Important Note: Only a dentist or physician may diagnose pathological (disease) conditions.

    • Role of dental assistants: Recognize differences between normal and abnormal conditions appearing in the mouth.

Making a Diagnosis

  • Types of Diagnosis:

    • Historical Diagnosis:

    • Involves obtaining personal history, family history (including genetic disorders), medical history (including medications taken), dental history, and the history of the lesion (duration, any changes, pain).

    • Clinical Diagnosis: Assessed based on the clinical appearance of the lesion including:

    • Color

    • Size

    • Shape

    • Location

    • Radiographic Diagnosis: Supplements the diagnostic process by providing information related to:

    • Periapical pathology

    • Internal resorption

    • Impacted teeth

    • Microscopic Diagnosis:

    • Involves taking a biopsy that is sent to a pathology laboratory for microscopic evaluation leading to a definitive diagnosis.

    • Laboratory Diagnosis:

    • Involves testing clinical specimens such as:

      • Secretion

      • Discharge

      • Blood

      • Tissue

      • Urine

    • Therapeutic Diagnosis: Made by administering a treatment and observing the response.

    • Example: For Angular Cheilitis, if the anti-fungal cream resolves the issue, it indicates a fungal cause rather than a deficiency in B-complex vitamins.

    • Surgical Diagnosis: Conducted via findings from a surgical procedure.

    • Differential Diagnosis: A list of possible conditions sharing the same symptoms, with further testing determined by the dentist for a final diagnosis.

Acute and Chronic Inflammation

  • Inflammation: The body’s protective response to irritation or injury.

    • Classic Signs of Inflammation:

    • Redness

    • Swelling

    • Heat

    • Pain

  • Acute Inflammation:

    • Characteristics: Minimal, lasts shortly, and heals or repairs quickly.

    • Examples of causes: Biting tongue or cheek, pizza burns, excessive citrus consumption.

  • Chronic Inflammation:

    • Occurs when injury or irritation persists.

    • Inflammation of specific tissues is described using the suffix –itis, as in:

    • Gingivitis

    • Periodontitis

    • Pulpitis

    • Causes include poor oral hygiene, poorly fitting dentures, uncontrolled diabetes, autoimmune diseases, and acne.

Oral Lesions

  • Definition: A broad term for abnormal tissues in the oral cavity, which can be a wound, sore, or other tissue damage caused by injury or disease:

    • Classifications:

    • Lesions extending below or above the mucosal surface

    • Flat lesions or even with the mucosal surface

    • Raised lesions

Lesions Extending Below Mucosal Surface

  • Key Types:

    • Ulcer: A break in the mucosa resembling a crater, ranging from 2 mm to several centimeters.

    • Erosion: A shallow injury in the mucosa caused by mechanical trauma, featuring ragged, painful margins.

    • Abscess: A collection of pus typically at the apex of a tooth, caused by bacteria from decay or severe periodontal infection.

    • Cyst: A fluid or semisolid sac that may contain non-infectious material, potentially forming around an unerupted tooth.

Lesions Extending Above Mucosal Surface

  • Key Types:

    • Blisters (Vesicles): Filled with watery fluid, resembling blisters from ill-fitting shoes, rarely seen in the oral cavity.

    • Pustule: Similar in appearance to blisters but contains pus.

    • Hematoma: Similar to blisters but contains blood.

    • Plaque: A patch or flat area slightly elevated from the surface, not equivalent to dental plaque.

Lesions Even with the Mucosal Surface

  • Key Types:

    • Patch: A well-defined area of discoloration, flat or even with the mucosa.

    • Ecchymosis: The medical term for bruising.

    • Petechiae: Small pinpoint round spots resulting from bleeding.

Raised or Flat Lesions

  • Key Types:

    • Nodules: Round solid lesions, may be below the surface or slightly elevated, feeling like peas under the surface when palpated.

    • Granuloma: Describes a type of nodule containing granulation tissue, may appear swollen on the gingival surface or as a periapical granuloma at the apex of a nonvital tooth.

    • Tumors (Neoplasms): Any mass of tissue growing beyond normal size with no useful purpose, which can be benign (not life-threatening) or malignant (life-threatening).