Periapical inflammatory pathology Flashcards
What 3 things must be completed before a radiographic examination
History
Examination
Review of prior imaging
What 2 things are present on a radiograph with normal periapical tissues
Radiolucent (black) line of PDL space that is even width around the tooth
Radioopaque (white) line of lamina dura that is continuous around root
Describe the trabecular bone density and pattern in the mandible
Thick bone density
Horizontally aligned
Describe the trabecular bone density and pattern in the maxilla
Finer bone density
No predominant pattern
What 3 things are present on a radiograph of periapical tissues of developing teeth
The apical papilla- circumscribed area of radiolucency at the apex
Radioopaque line of the lamina dura is intact
Funnel shaped developing root
What do plain radiographs show
2D imagine of complex 3D structure
Describe superimposition in dental radiographs
Normal anatomical structures superimposed to the apical tissues
What type of imaging does superimposition occur on
Intro oral and extra oral
What does superimposed images appear as
Radiolucent or radioopaque shadows
Why is superimposition an issue in periapical radiographs
Can mimic or obscure apical pathology
Name 6 places where superimposition causes radiolucent shadows
Maxillary antrum
Nasopalatine foramen
Mental foramina
Oral air space
Mental fossa
Submandibular foss
What effect do radiolucent shadows have on the PDL
PDL may appear more radiolucent or widened but will still be continuous and well defined
What effect do radiolucent shadows have on the lamina dura
Lamina dura may appear less obvious or not visible
What effect do radiolucent shadows have on the alveolar bone
Radiolucency in the alveolar bone at the tooth apex
Name 4 places where superimposition causes radioopaque shadows
Mylohyoid ridge
External oblique ridge
Zygomatic buttress
Soft tissues of the nose/lip
What effect can radioopaque shadows have on apical tissues
May obscure them
What is periapical inflammatory pathology
Lesions that form around the apex of a tooth in response to inflammation
What causes periapical inflammatory pathology
Usually caused by bacterial invasion of the root canal system and pulp necrosis
Describe how periapical inflammation occurs
- Bacterial ingress via caries, cracks, etc
- Becomes reversible pulpitis, then irreversible pulpitis, then pulp necrosis, then root canal system becomes infected
- Bacterial and necrotic pulpal products leak out apical foramen
- Periapical periodontitis occurs to confine infection/bacterial egress
- Results in bone resorption, formation of granulation tissue (cysts may also occur) resulting in a radiolucency
- Note- Bone formation can also occur (or combination of resorption and formation), may result in corticated margin and/or general sclerosis of adjacent bone
What are the 5 signs of inflammation
Swelling
Pain
Heat
Redness
Loss of function
What happens in the apical tissues after pulpal necrosis/bacterial ingress
An inflammatory exudate accumulates in the apical tissues
What type of inflammatory response at the apex of the tooth is dependent on what 2 things
The infecting organism and its virulence
Host response/defence mechanisms
Certain features of periapical inflammatory pathology are more common in what 2 types of inflammation
Acute
Chronic
In a PA radiograph, you cannot differentiate between what 3 things
Abscess
Granuloma
Cyst
What happens in initial acute inflammation
Inflammatory exudate accumulates in the apical PDL. This is acute apical periodontitis
What happens radiographically in initial acute inflammation
No change
Widening of the apical PDL space
Lamina dura intact or partially visible
What happens in the initial spread of inflammation
resorption and destruction of the apical bony socket
What happens radiographically in the initial spread of inflammation
Loss of apical lamina dura
Periapical radiolucency
What does the appearance of an abscess radiographically depend on
course of disease, treatment received
How long does it take for radiographic appearances of an abscess to catch up with the symptoms
approx 10 days
Radiographically what may you see with an abscess
Ill defined radiolucency described as rarefying osteitis
What happens with further spread of inflammation
further spread an destruction of the apical alveolar bone
What can you see radiographically with further spread of inflammation
further bone loss at the tooth apex (increased size, more radiolucent)
What does rarefying osteitis mean
Rarefying= radiolucency
Osteitis= inflammation of bone
What happens with initial low-grade chronic inflammation
minimal destruction of the apical bone
Dense bone laid down in apical region
Radiographically, what can you see with initial low grade chronic inflammation
dense sclerotic radioopaque bone around the apex, often with varying degrees of apical ligament space widening or radiolucency
Sclerosing osteitis
What is sclerosis osteitis known as
Condensing osteitis
Focal sclerosing osteitis
What are the symptoms of sclerosing osteitis
Often symptomless
Where is sclerosing osteitis often evident around
roots of lower first molars
What can you see radiographically with sclerosing osteitis
May be no radiolucent component
May be halo of sclerosing osteitis surrounding an area of rarefying osteitis
What happens in the later stages of chronic inflammation
apical bone is resorted and dense bone is laid down around the area of destruction
Name 2 histological diagnoses
Periapical granuloma
Radicular cyst
What can you see radiographically with Later stages of chronic inflammation
Circumscribed, well defined radiolucent area of bone loss at the apex surrounded by sclerotic dense bone, may be corticated
What’s similar about apical granulomas and radicular cysts
Both largely asymptomatic unless secondarily infected
Well defined and can be corticated or uncorticated depending on chronicity
What is the diameter of 2/3 granulomas
Less than 1cm
What does it mean if a granuloma is 1-1.5cm in diameter
The granuloma is a cyst
What is the diameter of 2/3 cysts
More than 1.5cm
What are endo-perio lesions
lesions that involve both the pulp and periodontal tissues
What were endo-perio lesions previously known as
Perio-endo lesions or combined lesions
What are the 2 main types of endo-perio lesions
Endo-periodontal lesion with root damage
Endo-periodontal lesions without root damage
What are the 3 types of endo-periodontal lesions with root damage
root fracture or cracking
Root canal or pulp chamber perforation
External root resorption
What are the 2 types of endo-periodontal lesions without root damage
endo-periodontal lesion in periodontitis patients
endo-periodontal lesion in non-periodontitis patients
what are the 3 grades of endo-periodontal lesions in periodontitis patients
Grade 1- narrow deep periodontal pocket in 1 tooth surface
Grade 2- wide deep periodontal pocket in 1 tooth surface
Grade 3- deep periodontal pockets in more than 1 tooth surface
what are the 3 grades of endo-periodontal lesions in non-periodontitis patients
Grade 1- narrow deep periodontal pocket in 1 tooth surface
Grade 2- wide deep periodontal pocket in 1 tooth surface
Grade 3- deep periodontal pockets in more than 1 tooth surface
What is the common radiographic appearance of endo-perio lesions
Signs of apical pathology with a wide periodontal ligament space or communicating periodoctal defect
How does most inflammatory pathology manifest
However…
Apically
However it can manifest anywhere along the root surface
Why can inflammatory pathology manifest along the root surface
Due to the presence of
Normal anatomy- lateral and frugal canals
Iatrogenic- perforation
Pathologic- perforations, cracks, fractures
What may double dense shadows be related to
clinically apparent chronic sinus
When can double dense shadows also be seen
following peri-radiculat surgery i.e. apicectomy
In double dense shadows, imaging appearance reflects what
Perforation of the vortices and degree of bone loss which is present
Radiographically what can you see with external root resorption
root may look irregular in outline or have a blunted apex
What is osteomyelitis
Infectious inflammation of bone and bone marrow
What are the 4 causes of osteomyelitis
Apical pathology
Surgery
Trauma
Idiopathic
What are the 5 variable clinical and imaging features of osteomyelitis
Indolent to aggressive
Sclerosis
Lyric/moth eaten appearance
Bony sequestra
Periostea’s bone formation
Describe the radiographic appearance of periapical inflammatory pathology
No change
Widening of apical PDL (well defined, corticated)
Chronic-may see scleorsing osteitis, external root resorption
Describe the radiographic appearance post endodontic treatment even if satisfactory
Healing with fibrous tissue may leave residual radiolucency
Radiolucency may initially increase in size following apical surgery
Name 3 other common causes of periapical radiolucencies and radioopacities
Normal anatomy, artefact, superimposition
Benign (cemento-ossesous dysplasia, hypercementosis, dense bone islands)
Benign and malignant tumours including metastases
What can malignancy mimic
A localised area of infection
List 5 potential signs of concern
Spiking restoration and an irregular radiolucency with a portly defined border
Tooth mobility in the absence of periodontal disease or floating teeth
Hair on end/sunburst appearance
Alternated sensation or anaesthesia
No improvement despite treatment
