Histopathology of periapical disease Flashcards
look at slides for histology pics
look at slides for histology pics
Which periodontal fibres insert into alveolar bone?
Sharpey’s fibres
run obliquely across PDL space and insert into bone to anchor tooth within socket
PDL contains epithelial remnants of Hertwig’s root sheath called
Rest cells of Malassez
What are rest cells of Malassez
epithelial remnants of Hertwig’s root sheath in PDL
Lamina dura
Thin layer of cortical bone outlining PDL space, seen as white gap on radiograph
Can change path if there is a periapical disease
Classification of periapical disease: inflammatory
Periapical periodontitis
Classification of periapical periodontitis: reactive
‘Osteosclerosis’
Hypercementosis
Ankylosis
Cemento-osseus dysplasia
Classification of perapical periodontitis: neoplastic
Benign cementoblastoma
Perapical periodontitis
Almost always arises as consequence of pulp death due to caries
May be traumatic (e.g. blow to tooth)
Periapical periodontitis: aetiology
Infection (bacterial) -via root canal (caries) -via periodontium (e.g. pocket) Trauma -physical: direct blow, high filling, malocclusion, bruxism -chemical: via root canal -mechanical: root filling
Symptomatic periodontitis
Non-vital tooth –> symptomatic (acute) PP –> acute periapical abscess –> acute alveolar abscess –> cellulitis or chronic abscess
Can become chronic, chronic can become acute
Acute periapical abscess
Bacteria -mixed anaerobes -root canals or peri-apex Primary abscess Radiographic changes
Symptomatic periapical periodontitis
Confined to periapical space Localisable pain Tooth elevated Little radiographic change May be transient or persistent
Spread of infection
Tracking of pus -PDL -root canal (if open) -through bone (sinus formation) Influence of anatomy -antrum -muscle attachments -soft tissue (cellulitis) Bone - osteomyelitis
Osteomyelitis
Rare
Pxs on bisphosphonates
Pxs who have had radiotherapy
Where may an abscess on an upper tooth drain to
Maxillary sinus From central incisor --> infraorbital region Soft tissues of cheek Nasal passage Intraoral Palate
Sinus tract
Alveolar abscess - chronic
Discharge intraorally
Cyclical symptoms as it fills up, then discharges
Where may an abscess on a lower tooth drain to
Intraoral
Lower incisor –> the chin
Mandible
Floor of mouth
Periapical granulomas
Mass of inflamed fibrous CT at base of apex of tooth
Granulation tissue
Loss of bone and replacement
Fibroblasts, macrophages, blood supply
Periapical granuloma: histology
Fibrous capsule
Granulation tissue
Inflammation
-lymphocytes, plasma cells, macrophages, occasional neutrophils
Epithelium - rest of Mallasez may proliferate
Bone resorption: osteocalsts
What can periapical granuloma lead to
Radicular cyst
Cysts of the jaws - odontogenic
Inflammatory
-radicular (most common)
-paradental
Developmental (a lot of types)
Radicular cyst
Arise in PDL from epithelial rests of Malassez as result of inflammation following death of pulp
Always associated with non-votal tooth
Types of radicular cysts
Apical: at apex of tooth associated with opening of root canal
Lateral: at side of tooth associated with lateral branch of root canal
Residual: radicular cyst which has persisited after extraction of associated tooth
Stimulus for proliferation of cyst
Inflammation
Apical granuloma –> radicular cyst –> periodontitis –> pericoronitis
Pathogenesis - radicular cyst
Caries –> non-vital pulp –> apical granuloma –> proliferating odontogenic epithelium –> cyst
Radicular cysts: histology
Wall (usually fibrous CT)
Lining (mostly epithelial lining)
-proliferative
Lumen filled with fluid and some cellular debris
-plasma cells
-antibodies
-cholesterol accumulation (from cell walls), seen as cholesterol clefts
Osteosclerosis
Rarefying osteitis (loss of bone): clinically more acute - radiolucent Focal sclerosing osteitis (sclerotic bone, more dense): ill-defined periapical radiopacity
Hypercementosis
Common - may be age related
Reactive change caused by:
-loss of function - tooth ‘overgrows’ (unerupted teeth)
-inflammation (in a granuloma or mobile teeth with periodontitis)
-Paget’s disease
-idiopathic
Hypercementosis histology
Thick layer of cementum around root which is indistinguishable from bone
Ankylosis
Hypercementosis obliterates PDL and fuses with alveolar bone
Cemento-osseus dysplasia
Reactive lesions Age 30-50 Often females Multiple radiopacities -around tooth roots -in edentulous areas Composed of irregular trabeculae of woven bone and cementum in fibrous stroma (fibro-osseus)
Florid cemento-osseus dysplasia (Gigantiform cementoma)
Often in edentulous areas Irregular radiopacities Masses of fused bone and cementum-like tissue Reactive, 'scarred bone' Calcified bodies which fuse into a mass
Cementoblastoma
Benign neoplasm Age 10-40 Radiopaque lesion attached to tooth root Usually mandibular molar teeth Composed of -sheets of cementum and osteoid -many plump 'osteoblasts' Resembles osteoblastoma
