Radiolucency Flashcards
What is a radiolucency
A darker area on a radiograph
Why do radiolucencies occur?
Due to:
- Thinning or hard tissue relative to the adjacent area
- Reduced hard tissue mineral
Why does caries use a radiolucent area in the tooth
Due to reduction of mineral content
What can cause a radiolucency in dentistry
- Normal anatomy
- Artefact
- Pathology
Give examples of normal anatomy that appear radiolucent on a radiograph
- Maxillary antrum
- Mental foramen
- Submandibular fossa
Does overexpose or underexposure lead to a more radiolucent image
Over exposure
How do we describe a radiolucency
- Position/ site
- Size
- Shape
- Locularity
- Margin
- Effect on adjacent structures
What does odontogenic mean
Derived from the dental tissues
How do describe the relationship of a radiolucent to dentition/ a tooth
- Periapical
- Pericoronal
- Radicular
What does Periapical mean
At the apex
What does pericoronal mean
Around the crown
What does radicular mean
Related to the root
What words do we use to describe the margin of a radiolucency
- Corticated VS Moth eaten
- Well defined vs ill-defined/ indistinct
- Smooth vs punched out
Describe margins of a radiolucency that suggest a slow benign growth
- Corticated
- Well defined
- Smooth
Describe margins of a radiolucency that suggest rapid more infectious or malignant growth
- Moth eaten
- Ill defined/ indistinct
- Punched out
What can radiolucencies surrounding teeth suggest
- Resorption
- Displacement
- Delayed eruption
- Loss of associated lamina dura
List some pathological causes of radiolucencies
- Cysts
- Tumours
- Bone related lesion
- Bone diseases
What are cysts split into
Odontogenic or non odontogenic
What can odontogenic cysts be split into
- Inflammatory
2. Developmental
What are tumours split into
Benign vs malignant
List bone bone relates lesions that can cause radiolucencies
- Giant cell lesion
2. Cemento osseous dysplasia
List bone bone diseases that can cause radiolucencies
- Osteoporosis
- Sickle cell disease
- Hyperparathyroidism
What Is a cyst
A pathological cavity within the tissues
Describe cysts
- Can be filled with fluid, semifluid or gas
2. Usually lined by epithelium
Are cysts caused by an accusation of pus
no but they can become secondarily infected with pus
What can epithelial lined cysts of the jaws be split into
odontogenic vs non odontogenic
What can odontogenic cysts of the jaw be further split into
Inflammatory vs developmental
List some epithelial lined odontogenic inflammatory cysts of the jaw
- Radicular
2. Residual
List some epithelial lined odontogenic developmental cysts of the jaw
- Dentigerous
- Keratocyst
- Lateral periodontal
List some epithelial lined NON odontogenic cysts of the jaw
Nasopalatine duct cyst
List some non epithelial lined cysts of the jaw
- Solitary bone cyst
2. Aneurysmal bone cyst
Talk through the symptoms of a cyst
- Frequently asymptomatic
- Patient may be aware of swelling or numb
- Can be painful if secondarily infected
How are cyst usually diagnosed
As an unexpected incidental finding on a radiograph
Name the most common type of cyst
Inflammatory cysts
Where do radicular cyst form
At the apex of a non vital tooth
Name the most common cyst of the jaw
Radicular cysts (70%)
What can radicular cysts be mistaken for on a radiograph
Periapical granuloma
How can be begin to differentiate a periapical granuloma from a radicular cyst
Size
The bigger the radiolucency the more likely it is to be a radicular cyst
Describe how radicular cysts present on a radiograph
- Round, unilocular, smooth and well define
- Continuous with lamina dura of the affected tooth
- Adjacent teeth displaced
- Buccal expansion
What is a residual cyst
A radicular cyst remaining following extraction of the tooth
Describe how a residual cyst may appear on a radiograph
Unilocular, well defined and corticated
What is a dentigerous cyst
Fluid accumulation between reduced enamel epithelium and enamel
What are dentigerous cysts associated with
Crowns of un erupted and displaced teeth
Are dentigerous cysts common
Yes account fro 20% of all jaw cysts
In which sites are dentigerous cysts common
Lower 8s Upper 3s Lower premolars Upper 8s Supernumeraries
How can a dentigerous cyst affect the oral cavity
- Teeth can be displaced but rarely resorbed
- Antrum floor can be displaced
- Buccal expansion may occur
What other terms are used to describe keratocysts
- Keratocystic odonotgenic tumour
2. Premordial cyst
Are keratocysts common
No rare (<5%)
In which sites are keratocysts common
- Posterior body. angle of mandible
- Anterior maxilla, canine region
- Can appear in dentigerous relationship
Describe how keratocysts can appear ragiogrpahically
- Pseudolocular or multilocular
- Well defined, corticated
- Frequently non or minimally expansile
What can cause a keratocysts to recur
- Thin friable lining
2. Daughter cysts
How are keratocysts managed
Surgically
In which syndrome are multiple keratocysts common
Gorlin Goltz syndrom
Where are lateral periodontal cysts found
Mandibular premolar
Anterior maxilla
What are lateral periodontal cysts associated with
Vital tooth
Describe how a lateral periodontal cyst looks on a radiograph
- Round/ oval radiolucency between apex and ADJ
- Usually less than a cm
- Unilocular
- Adjacent teeth may be displaced
Name the most common non odontogenic cyst of the jaws
Nasopalatine duct cyst
How common are Nasopalatine duct cyst
Approx 1% of population affected
Where are Nasopalatine duct cysts found
Usually midline
Describe how Nasopalatine duct cysts appear on a radiograph
- Unilocular and round
2. May appear chart shaped due to superimposition of anterior nasal spine
What are solitary bone cysts also Called
- Traumatic
- Haemorrhagic
- Unicameral
Where are solitary bone cysts usually found
Mostly in mandible, anterior and in the premolar, molar region
Do solitary bone cysts have an epithelial lining
no
What can benign tumours be split into
Odontogenic
Non Odontogenic
What can malignant tumours be split into
Primary or secondary
Give examples of odontogenic benign tumours
- Ameloblastoma
2. Odontogenic myxoma
How do begin tumours present radiographically
Initially radiolucent but calcify with maturity
Give an example of a odontogenic benign tumours
Intrasosseous haemangioma
Name the most common odontogenic tumour
Ameloblastoma
Are Ameloblastomas common
No they are rare
Describe Ameloblastomas
Aggressive but non metastasising
Where are Ameloblastomas usually found
Posterior to the mandible
Describe how Ameloblastomas present radiographically
- Usually mutlolocular bur can be unilocular If unicystic Ameloblastoma
- Expansile
- Well defined smooth margin
- Root resorption seen
In whom are odontogenic myxomas seen in
Young adults but rare condition
Describe how odontogenic myxomas present radiographically
Multilocular lesions with internal septa arranged at right angles
Expansile and can displace teeth
What are haemangiomas
Vasulcar tumours in the marrow space
Describe how haemangiomas present radiographically
very variable
most common: multilocular, expansile resin with a soap bubble appearance
Displacement and resorption of teeth is common
Where are intrinsic primary malignant bone tumours four
They arise within the bone
Give an example of an intrinsic primary malignant bone tumours
Osteosarcoma
Give an example of an extrinsic primary tumour involving bone
Squamous cell carcinoma
What are secondary tumours
Metastatic tumours deposited from a primary tumour elsewhere in the body
What are osteosarcomas
It is a rare primary intrinsic bone malignancy that causes rapid destruction
Describe how osteosarcomas present radiographically
- Osteolytic or Osteoscarlotic
- Ill defined, ragged margins
- Loosening of associated teeth
Where are squamous cell carcinomas
mandible more common than maxilla
How do squamous cell carcinomas present radiographically
Once bone is involved appearance ranges from crystal erosion to gross resorption
irregular bone destruction and not corticated
Tumours from were can metastasis to the jaw?
- Breast
- Bronchus
- Kidney
- Prostrate
- Thyroid
How can secondary bone tumours present radiorgpahically
Irregular areas of bone destruction mot corticated
Where can secondary bone tumours of jaw arise
Along the inferior alveolar cancel and mental foramen region
How do lymphoreticular tumours of the bone present radiographically
Multiple round unilocular well defined but not corticated lesions
What is langerhans cell disease
Proliferation of the langerhans cells and eosinophilic leucocytes producing tumour like lesions
What can langerhans cell disease cause
Tumour like lesions in bone
How does langerhans disease present radiographically
Round, unilocular
Well defined but not corticated
Floating teeth
wHat can giant cell lesions be caused by
- Central giant cell granuloma
- Hyperparathyroidism
- Cherubism
- Anerurysmal bone cyst
What are giant cell granulomas
Benign proliferations of fibrous tissue
Where are giant cell granulomas found
Often anterior mandibel
How do Giant cell granulomas appear radiographically
- Uni lor multilocular
- Smooth and well defined
- Corticated
- Displaced teeth
What is hyperparathyroidism
A condition linked with elevated parathyroid hormone
What does hyperparathyroidism cause
Generalised decrease in bone density (osteopenia)
How does bone appear in patients suffering from osteopenia
Vey fine trabecular pattern ground glass appearance
What is cherubism
A rare autosomal dominant condition
How can cherubism present radiographically
Bilateral multilocular radiolucencies at angle of mandible
What is osteoporosis
Generalised decrease in bone mass
What can osteoporosis increase patents risk of
Fractures