Exam 3 Flashcards Preview

Radiology > Exam 3 > Flashcards

Flashcards in Exam 3 Deck (36)
Loading flashcards...

What are the characteristics of a tooth to raise level of suspicion that there are caries?

  • It appears as a chalky white spot
  • or an opaque - or dark brownish spot (past activity)


What is the best image to identify caries?



What is the most radiopaque and radiolucent material in a radiograph?

  • Most radiopaque - metal
  • Most radiolucent - air, fat, gas


At what point will demineralization be to see it on a radiograph?

  • 55-60%
  • Lesions confined to enamel may not be evident until 30-40% demineralization
  • May extend well into dentin before cavitation occurs


Describe caries that is seen along the root surface along the CEJ.

  • Radiolucent
  • Diffuse rounded inner border where the tooth substance has been lost
  • Saucer shaped
  • Usually at or Below gingival margin


What point does caries cause cavitation? How much demineralization needs to be present?

  • Demineralization to cavitation takes 12-18 months
  • Radiographs do not show incipient caries, minimum of 55-60% demineralization must occur before changes appear
  • Enamel 30-40%


With perio disease, what are the limitations we have with current radiographs?

  • 30-50% demineralization change is required for a lesion to be radiographically detectable
  • 2D images record 3D structures - superimposition of buccal and lingual bone


What are the periodontal ADA classifications?

  • Type 1 - gingivitis, no bone loss
  • Type 2 - early perio, loss of crestal cortication - 20-30% mild to moderate bone loss
  • Type 3 - moderate perio, 30-50% moderate to severe bone loss
  • Type 4 - advanced perio, over 50% bone loss


What does it mean to see a sclerotic area?

  • Appears to be radiopaque, deposition of bone on existing trabeculae at expense of marrow
  • Represents a wider zone of transition made up of thick radiopaque border


Describe the process of sclerosis.

  • Trabeculae become thickened with more deposition of bone
  • Overall bone density increases as an inflammatory reaction
  • More bone is deposited at expense of marrow


What is the unique radiographic presentation of localized aggressive perio disease?

  • Age: under 30
  • Can show vertical or horizontal bone loss
  • Attachment loss involving incisors & first molars
  • The amount of bone loss correlates with the time of tooth eruption
  • Shows up around puberty
  • Drifting and mobile incisors and early loss of 1st molars
  • Maxillary more involved


What will you see clinically in patients with systemic diseases, such as diabetes - with regards to periodontal status?

  • Increased bone loss
  • Scleroderma (widening of PDL, lamina dura intact)
  • Histiocytosis X
  • Protein breakdown - degenerative vascular changes, lowered resistance to infection


What are the characteristics of supernumerary teeth?

  • Mesiodens - between central incisors
  • Peridens - between premolars
  • Distodens - between molars
  • Associated with cleidocranial dysplasia, familial adenomatous polyposis (Gardner's syndrome), pyknodysostosis


What are the most common teeth that present as congenitally missing?

  • 3rd molars
  • 2nd premolars
  • max laterals
  • mandibular centrals


How does macrodontia form? And what are the 2 forms?

  • Gemination - "twisting"
    • When a single tooth bud attempts to divide
    • Will present with normal tooth count
  •  Fusion
    • Present with a missing tooth


Describe the characteristics of Taurodontism.

  • Bodies of teeth appear elongated, short roots, more apically positioned pulpal floor
  • May occur in any tooth
  • Usually in molars and less often in premolars


What are the characteristics of dens invaginitus?

And what is the most severe to least severe forms?

  • Due to invagination or infolding of enamel surface into the interior of a tooth
  • Appears as a small pit between cingulum and lingual surface of incisor
  • Cingulum (dens invaginatus)
  • Incisal edge (dens in dente)
  • Most severe - dilated odontome, dens in dente, dens invaginatus


How does amelogensis imperfecta present radiographically?

  • Enamel formation mutations
  • Hypoplastic - roughly square shaped crowns, loss of contacts
  • Hypocalcification - normal size teeth, fractures, enamel permeability and staining
  • Hypomaturation - mottled enamel with normal thickness, cloudy white, yellow, brown, "snow-capped" teeth
  • Square crown, thin radiopaque layer of enamel, low or absent cusps, open contacts, picket fence anteriors


What are the presentations of dentinogenesis imperfecta?

  • Normal crown size
  • Constricted cervical portion, bulbous 
  • Roots short and slender, normal bone
  • Partial pulp chambers - complete obliteration
  • Rarefying osteitis - microscopic communication
  • Clinically
    • Amber like transluceny
    • Enamel fractures easily


What are the charactertistics of enamel pearls?

  • Globule of enamel 1-3mm, 3% population
  • Usually solitary
  • Below crest of gingiva 
  • Furcal areas of molar teeth
  • May predispose to pocket formation
  • Radiograph
    • Smooth, round, similar opacity to enamel of crown - no treatment


What's the difference between radiopaque and radiolucent inflammatory lesions?

  • Radiopaque
    • bone deposition in response
    • mostly sclerotic lesions (apical sclerosiing osteitis)
    • Enostosis (dense bone island)
  • Radiolucent
    • bone resorption in response
    • mostly lucent lesion (apical rarefying osteitic)
    • periapical due to necrotic pulp
    • osteomyelitis - infection out the apex


What is the term and process when periapical inflammation gets out of control?

  • Condensing osteitis (sclerosing osteitis, rarefying osteitis)
  • Radiolucent, sclerotic


What happens if periapical lesion is untreated or in a patient with diabetes or other immunocompressing factors?

  • A sinus tract could develop
  • Osteomyelitis
  • Cellulitis


What is the common source of osteomyelitis and how does it appear radiographically?

  • Pyogenic organisms reach bone marrow from abscessed teeth or post-surgical infection
  • Diffuse, uncontained inflammation of bone
  • Most common in posterior mandible


What is the most common cyst?

  1. Radicular cyst
  2. Dentigerous cyst


How does osteoradionecrosis look radiographically and where is it usually seen?

  • Presence of exposed bone for at least 3 months at any time after delivery of radiation therapy
  • Poor blood supply
  • Most common in posterior mandible**
  • Sequestra (dead bone)
  • Extensive bone resorption and presence of a sequestrum


What is the mechanism of bisphosphonates?

  • Drug inhibits osteoclasts so the individual is not losing bone, they are maintaining it
  • Reduces bone metabolism
  • Seen in post-menopausal women or those with malignant disease (myeloma)



  1. Benign or malignant?
  2. What do they do to surrounding structures?
  3. Can they displace teeth?
  4. Cause expansion of mand/max?
  5. Cause resorption of bone?
  6. Fast or slow growing?

  1.  Benign
  2. Can expand mandible, resorb teeth, displace IA nerve canal inferiorly
  3. Yes
  4. Yes
  5. Yes
  6. Slow


Describe the most common cysts in jaw:

  • Radicular - (rests of epithelial cells Malassez, PDL stimulated to proliferate and degenerate
  • Dentigerous - attaches at CEJ
  • Lateral Periodontal - arise from epithelial rests in periodontium lateral to root
  • NOT primordial


Keratocystic Odontogenic Tumor (KCOT)

  1. What age group?
  2. Most common location?
  3. Above/below IA canal?
  4. Radiographic presentation?
  5. Do they re-occur?

  1. Anywhere, anytime, male predominance
  2. Posterior mandible, highly aggressive
  3. Usually seen above IA
  4. Large radiolucent lesions
  5. Yes, up to 60% of the time
  6. Related to gorlin syndrome


Benign tumor:aka dense bone islands, DBI, focal idiopathic, enostosis

  1. How do they present radiographically?
  2. Where are they most commonly found?
  3. Is treatment necessary?
  4. Are they painful? 

  1. Relatively smooth borders, well-defined and sometimes corticated. Radiolucent, radiopaque or mixed.
  2. Odontogenic lesions can be found above IA nerve
  3. Yes - excision for most, ameloblastoma, CEOT
  4. Some- osteoblastoma, osteoid osteoma


What are the 2 kinds of odontomas?

3. How do they appear radiographically?

4. Age group?


  1. Complex - nondescript mass of dental tissue (dentin, cementum, enamel)
  2. Compound - multiple, well-formed teeth (denticles)
  3. Calcified radiopaque internal structure, thin radiolucent capsule, intereference with eruption of associated teeth
  4. Second decade of life, stops after teeth stop developing


Where do benign cementoblastomas occur? and what's their radiographic presentation?

  • Mandibular premolar area
  • Bulbous growth around and attached to apex of tooth, more often in mandible or first molar roots
  • Mixed radiopaque and radiolucent lesion
  • Internal = radiopaque


When you want to evaluate someone 3-D, what image modality will you use?



How do tori appear radiographically?

  • Dense radiopaque with well-defined borders
  • Mandibular PA appears as radiopaque shadow superimposed on the rooths of premolars and molars (about 3 teeth)
  • Mandibular tori are sharply demarcated anteriorly, less dense and less well defined posteriorly


What is the sunray pattern?

What kind of lesion do you want to consider when you see this?

  • Osteosarcoma shows sunray spicules
  • Speculated bone pattern
  • Think => hemangiomas or consider osteogenic sarcoma in young patients