Dentals

Dental Anatomy and Imaging Overview

Tooth Structure and Palmer’s Notation

  • Color Codes for Tooth Structures:

    • Pink = enamel

    • Blue = dentin

    • Red = bone

    • Green = pulp

  • Palmer’s Notation:

    • A method for designating individual teeth using a quadrant system.

    • Four quadrants:

      • Upper Left: Maxillary

      • Upper Right: Maxillary

      • Lower Left: Mandibular

      • Lower Right: Mandibular

Tooth Identification

  • Each tooth is assigned a number which indicates its type:

    1. Central Incisor

    2. Lateral Incisor

    3. Canine

    4. First Premolar

    5. Second Premolar

    6. First Molar

    7. Second Molar

    8. Third Molar

Types of Dental X-Rays

Intraoral X-Rays

  • Two types:

    • Periapicals:

      • Bisecting angle and paralleling techniques.

      • Clinical Indications:

        • Apical infection/cyst

        • Impacted tooth

        • Root morphology before surgery

        • Evaluating implants

    • Bite Wing:

      • Captures interproximal areas and alveolar bone.

      • Clinical Uses:

        • Caries detection

        • Periodic reviews

        • Evaluating alveolar bone level

        • Evaluating pulp chamber

    • Occlusal:

      • Exposes all maxillary or mandibular teeth.

      • Clinical Indications:

        • Detects unerupted teeth and evaluates pathology.

Extraoral X-Rays

  • Lateral Cephalometry:

    • Evaluates relationships between structures of the facial skeleton for orthodontics.

  • Orthopantomogram (OPG):

    • Provides panoramic view of the mandible, maxilla, and teeth.

    • Clinical Uses:

      • General evaluation of dental health, trauma assessment, infection evaluation, and growth monitoring.

Intraoral X-Ray Techniques

Periapical Techniques

  1. Parallel Technique:

    • Film is parallel to tooth axis; minimizes distortion and magnification.

    • Must use a film holder; may be uncomfortable for some patients.

  2. Bisecting Technique:

    • Used when the parallel technique is not feasible.

    • Quick and requires no holder but has a higher risk of magnification.

Bite Wing Technique

  • Patient bites on a tab to stabilize the film,

  • Captures both maxilla and mandible in one view.

Occlusal Technique Details

  • Maxillary occlusal positioning:

    • Patient seated with the occlusal plane horizontal.

    • IR positioned flat on occlusal surfaces; X-ray tube directed appropriately.

Extraoral Imaging Details

Orthopantomogram (OPG)

  • Provides rapid evaluation of jaw anatomy.

  • Patient considerations:

    • Remove jewelry and dental appliances, keep the bite block covered.

  • Advantages:

    • Broad anatomical view and lower radiation exposure compared to intraoral.

Lateral Cephalogram Positioning

  • Head in natural alignment, MSP parallel, mouth closed.

  • Utilizes a wedge filter for soft tissue clarity.

Pathologies Identified in Imaging

  • Cysts causing impacted teeth.

  • Ectopic tooth development.

  • Fractured mandible observations.