TOPIC: PERIODONTAL IMAGING AND DISEASES
🌟 IMPORTANT POINTS TO REMEMBER
🔸Technique Used: The standard exposure technique for periodontal imaging procedures is undoubtedly the intraoral radiography using a strict paralleling technique.
🔸Digital Radiography: In digital radiography dedicated software for periodontal filtering may offer an optimised image to inspect crestal cortication, lamina dura and periodontal ligament space. The drawbacks of this system for periodontal imaging remain the sensor rigidity and the restricted active area of the sensor and the cable. To avoid bite marks and damage to the latter, a clip system in conjunction with the beam-aiming device is essential but often not available.
🔸Panoramic Radiography: The panoramic image gives an overview of both the jaws including the teeth, their periodontal status and the adjacent anatomical structures.
🔸Normal Periodontium: The normal periodontium is characterised by an alveolar crest level 2 mm below the CEJ, a well-delineated alveolar crest, continued in a radio-opaque lamina dura bordering a radiolucent 0.2 mm periodontal ligament space.
🔸Initial Lesion: The initial periodontal breakdown becomes obvious as a local disappearance of the radio-opaque cristae and/or the lamina dura. The sharp edge and the corner between the alveolar crest and lamina dura are evidently lost.
🔸Horizontal Bone Loss: Horizontal bone loss implies that the interdental bone loss is horizontal and thus equal for buccal, lingual and approximal aspects.
🔸Vertical Bone Loss: It implies that the bone loss occurs at different rates on buccal or lingual bone plates, thus one side being resorbed more than the other, creating two bone levels, which can be visualised on the radiograph.
🔸Advanced Periodontitis: Periodontal breakdown in this stage is widely spread over the entire dentition, and the radiological observations confirm these clinical findings.
🔸Calculus: If calculus formation is persistent and large enough, it may be visualised radiographically as moderate and irregular radio-opaque structures attached to the roots.
🔸Occlusal Trauma: When dealing with occlusal trauma, one can radiographically detect the typical widening of the periodontal ligament.
🔸Systemic diseases: Detection of initial and often characteristic periodontal lesions (e.g. thinning or absence of the lamina dura) may even lead to an early diagnosis of the metabolic disease. In Paget disease, a generalised absence of the lamina dura as well as a hypercementosis of the roots is noticed. Other diseases with a generalised effect on the periodontium (e.g. absence of lamina dura) are hyperparathyroidism, hyperthyroidism, uncontrolled diabetes, Cushing syndrome, Langerhans cell disease, osteomalacia and scleroderma. Osteoporosis is another widespread systemic disease affecting the periodontium, but its relation with periodontitis is not yet fully understood.
📌 MULTIPLE CHOICE QUESTIONS (MCQs)
💡 Normal PDL space seen in the radiograph is
a. 0.15 mm
b. 0.25 mm
c. 0.2 mm
d. 1.5 mm
Answer: c
💡A Funnel-shaped defect or hourglass appearance is seen in the radiograph when
a. There is resorption in the buccal cortex
b. There is resorption in the lingual cortex
c. There is occlusal trauma
d. None of the above
Answer: c
💡Around implants, overload may lead to characteristic lesions, which appear in the radiograph as
a. Spiked root
b. Pear-shaped appearance
c. Hourglass
d. Saucer-like defect
Answer : d
💡Generalised absence of lamina dura is seen in
a. Fibrous dysplasia
b. Hyperthyroidism
c. Osteoporosis
d. Paget disease
Answer : d
💡Diffuse radiolucent gap with unclear margins on the approximal tooth surface, at the level of root below CEJ is called
a. Artefact
b. Cervical caries
c. Contrast effect
d. Cervical burnout
Answer : d
💡Full mouth radiographic examination consists of
a. 12 radiographs
b. 13 radiographs
c. 14 radiographs
d. 15 radiographs
Answer: c
💡 The radiographic beam is angulated at
a. 7–8°
b. 8–9°
c. 9–10°
d. 10–11°
Answer: a
💡 In IOPA,
a. Buccal bone plate can be seen
b. The lingual bone plate can be seen
c. None can be seen due to overlapping
d. Both can be visualized distinctly
Answer: c