Exam 3 Flashcards
(36 cards)
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?
Bitewing
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