Lecture 6 Flashcards
Radiographic Analysis of the Periodontium
identification of the periodontium on radiographs
gingiva not visible
alveolar bone (cortical, cancellous, alveolar crest, lamina dura)
PDL space
cementum
alveolar crest
surfaces of the bony crests are smooth and covered with a thin layer of cortical bone
thin white line
normal level is 2mm apical to the CEJ
alveolar crestal bone anterior vs posterior
anterior: thin and pointed
posterior: rounded or flat
crestal contour of the interdental bone
a good indicator of health
contour should be parallel to a line drawn between the CEJs of adjacent teeth
horizontal crest contour
when the CEJs of adjacent teeth are of the same level, the crest of the interproximal bone will have a horizontal contour
vertical/angular crest contour
when one of the adjacent teeth is tilted or erupted to a different height, the crest of the interproximal bone will have a vertical contour
lamina dura
appears as a continuous white line around the tooth root
radiographically is continuous with cortical bone layer of the crest of the interdental septa
periodontal ligament space
appears as a thin radiolucent line surrounding the tooth root
a widening of PDL space on radiograph indicates tooth mobility
benefits of radiographs for periodontal evaluation
bony changes caused by disease: early signs of disease, direction of bone loss, furcation involvement
implant assessment
periodontal abscess
local factors
early radiographic signs of disease
fuzziness in the crest of the interdental bone
widening of the PDLs
radiolucent lines in the interseptal bone
periodontal disease and direction of bone loss is determined by
using the CEJ of adjacent teeth as points of reference
horizontal bone loss direction
parallel to a line between CEJs of adjacent teeth
vertical bone loss direction
greater bone loss on the interproximal aspect of one tooth than on the adjacent tooth
types of periodontal pockets
suprabony
infrabony
suprabony pocket
occurs when there is horizontal bone loss and the junctional epithelium, forming the base of the pocket, is located coronal to the crest of alveolar bone
infrabony pocket
occurs when there is vertical bone loss and the junctional epithelium, forming the base of the pocket, is located below the crest of alveolar bone
assessment of bone loss
stage I: <15% bone loss
stage II: 15%-33% bone loss within first third of root
stage III and stage IV: extending to middle third and beyond of root/vertical bone loss
assessment of furcation involvement
early involvement not seen of a radiograph
furcation probe to assess clinically (Class I, II, III, IV)
furcations are easier to see on the mandible than maxilla
often greater than it appears on a radiograph
radiographic sign of peri-implantitis
loss of radiodensity around the osseointegrated implant
peri-implantitis alveolar bone changes
alveolar bone remodeling following the first year in function is normal (<2mm)
changes >2mm at any time point during or after the first year should be considered as pathologic
calculus detection
large interproximal calculus deposits may be visible on a radiograph
large facial and lingual deposits may be visible if there is severe bone loss on the surfaces
the ability to visualize calculus on a radiograph depends on the degree of mineralization and angulation of the x-ray beam
faulty restorations
can be detected on radiographs
can cause gingival inflammation, increase risk of periodontitis and alveolar bone resorption
faulty contours
between the first and second molar restorations create an open contact that may cause food impaction
radiographic signs of trauma from occlusion
widening of PDL
increased thickness of lamina dura
vertical bone loss
root resorption
used only as a supplemental aid in recognizing trauma
pulpal abscess
an infection of the tooth pulp
caused by trauma, deep caries
requires root canal treatment
apical bone loss
gingival abscess
limited to gingival margin
periodontal abscess
gingiva and deeper structures
caused by trauma, or pre-existing periodontal disease
pericoronal abscess
involves tissues around a partially erupted tooth
extensive bone loss
crestal bone loss of 5mm or greater may cause the coronal bone to be poorly visualized or not seen at all on normal bitewing radiographs
as a result, vertical oriented bitewings may be used
long axis of the film is rotated 90 degrees
limitations of radiographs
provide a 2D image of a 3D object
buccal alveolar bone can hide bone loss on the lingual aspect
palatal roots make furcation detection on the maxilla difficult
radiographs do not provide information about non-calcified components
radiographs do not show disease activity but they do show effects of the disease
radiographs do not reveal the following
presence or absence of periodontal pockets
exact morphology of bone destruction
tooth mobility (early)
early furcation involvement
condition/height of the bone on the buccal and lingual surfaces
level of the epithelial attachment
limitations of early bone loss detection
it must first be detected clinically with careful periodontal probing, not radiographically
by the time periodontal bone loss appears on a radiograph, it usually has progressed beyond the early stages of the disease
interseptal bony defects less than 3mm are not usually detectable radiographically
