Class 1 - Extraoral radiology

Lateral cephalogram

• Used in ortho treatment

• Assesses AP relationship b/w Mx & Md + skull

• Assesses skeletal + soft tissue relationship

• Monitors treatment progress & outcome

• Continues orthognathic surgical treatment planning

CBCT use - Wisdom, Ortho & Implants

• Wisdom teeth eval

  • Position inr el. to anatomical structures (mand canal)

• Orthodontics

  • Diagnostic assessmen + analysis of facial jaw/anomalies

  • Root resorption

  • Position & location of impacted/supernumerary teeth in relation to anatomy

  • TMJ

• Implantology

  • Eval height + width of AB

  • Precise distance to anatomical structures in planning

  • Possibility to use surgical guide - KSDT required in planning

  • Gold standard in planning

CBCT use - Perio, Oral, Facial, Maxo, TMJ & Endo

• Perio

  • Bone height

  • Furcation

  • Period surgery

• Maxo

  • Bening/Malignant formation

  • Calcification

  • SInuses

  • Injuries

  • Diagnosis of osteomyelitis

• TMJ

  • Assess morphology of condyle + surrounding tissues

  • Asses joint space + position of condyle in joint cavity.

  • Condylar surfaces

  • Arthritis, ankylosing + condylar abnormalities

• Endo

  • Additional canal ID

  • Root inclinations + anomalies

  • PA patho diagnosis in non-standard symptoms

  • Non-odontogenic patho diagnosis

  • Endo therapy complication diagnosis

  • Dentoalveolar injuries

  • Internal resoprtions

  • Apical surgery

PET-CT & Scintigraphy

• Scintigraphy - 2D nuclear medicine tech depicting active bone remodeling.

• PET- Tomographic nuclear medicine examination using positron-emitting radionuclides.

• Clinical relevance

  • Detection of primary metastatic tumors

  • Diagnosis of osteomyelitis

  • Evaluation od osteonecrosis in jaw & skeletal growth disorders

Where the patient’s tissue itself becomes radio source, image interpretation is based on signal intensity & localization.

USG - Ultrasound

• Principle - High frequency → different tissues have different echoes → echo perception

• Indications

  • Salivary gland eval

  • TMJ disc eval

  • Lymph node eval

  • Blood flow eval (doppler)

  • Inflammation/infection (abscesses & phlegmons)

  • Soft tissue formations

MRI - Magnetic Resonance Imaging

• Evaluation

  • TMJ + disc

  • Soft tissue

  • Leasions & inflammations

• NOT PERFORMED ON:

  • PT´s w/ metallic devices & soft tissue implants

• PERFORMED ON:

  • Dental implants, amalgam restorations.

  • Artifacts will be seen

Panoramic indications

• Treatment planning

  • Ortho → Check presence/absence of teeth

  • Implant planning → Assess vertical bone height

  • 3rd molar extraction → Position/condition before surgert.

• Assessment/diagnosis

  • Poor oral condition (after clinical exam)

  • Unerupted teeth/bone formation not seen in intraorals.

  • Perio evaluation, pockets <5mm.

  • Mandibular fractures

  • Maxillary sinus pathologies (basr, posterior, lateral walls)

• Review/Montior

  • TMJ joint changes → overview of condyles & joint area

Cons of OPG & CBCT

• OPG

  • Lower resolution than intraorals, geometric distortion, positioning sensistive, not ideal for caries diagnosis.

• CBCT

  • Higher radiodose than 2D imaging, more ecpensive, metal artifacts, Not for soft tissue imaging, overuse w/o indication (ALARA), training to interpret, Motion artifacts.

Analyzing OPG

• PT age & gender

  • Age characteristics

• Panoramic image → position & image formation.

• Anatomical local. of lesion

• Size, shape, borders & contours.

• Lesion structure → opaque, lucent, mixed.

• Effect on adjacent structures.

Patient position - Antero-posterior error

Patient too forward, too close to film. Teeth narrowed.

Patient position - Antero-posterior error

Patient too backwards, too far away from film. Teeth magnified & widened.

Patient position - Horizontal error

Pt rotated to right → left molar closer to film (smaller) & right molars further from film appear larger.

Patient position - Vertical error 1

Head & chin tipped down, frankfort plane not horizontal, occlusal plane distorted → Smiley

Patient position - Vertical error 2

Head & chini uppwards, frankfort not horizonral , occlusal plane distorted → Grumpy

Patient position - Air shadow

Failure to instruct patient to press tongue to roof of mouth.

Patient position - Movement

Failure to instruct patient to keep still