CIT CIT Radiography & Imaging 2 — Questions and Answers
Question 1: Which maxillary anatomical structure must be carefully identified on CBCT before planning posterior maxillary implants due to its direct impact on available bone height?
- Infraorbital nerve canal
- Maxillary sinus (Correct answer)
- Nasolacrimal duct
- Pterygoid plate
Correct answer: Maxillary sinus
The maxillary sinus must be identified and measured to determine available sub-sinus bone height or to plan a sinus augmentation procedure for posterior maxillary implant placement.
Question 2: Which radiographic landmark in the mandible is most important for measuring safe bone height in the premolar region?
- Mental foramen (Correct answer)
- Mandibular canal at the molar region
- Genial tubercle
- Mylohyoid ridge
Correct answer: Mental foramen
The mental foramen, which marks the exit of the mental nerve and vessels, is a critical landmark when measuring available bone height in the premolar region to prevent nerve injury.
Question 3: Why is the paralleling technique preferred over bisecting-angle technique for periapical radiographs used in implant monitoring?
- It produces brighter images with less exposure time
- It positions the sensor parallel to the implant with a perpendicular beam, yielding accurate and reproducible measurements (Correct answer)
- It requires less patient cooperation and is easier to perform
- It exposes the patient to less radiation per image
Correct answer: It positions the sensor parallel to the implant with a perpendicular beam, yielding accurate and reproducible measurements
The paralleling technique produces geometrically accurate, reproducible periapical images that allow reliable comparison of sequential radiographs to monitor crestal bone levels over time.
Question 4: What does the 'scout view' (localizer image) represent in a CBCT examination?
- A magnified high-resolution cross-sectional slice of the implant site
- A low-dose 2D overview image used to define the scan field of view before acquiring the full CBCT dataset (Correct answer)
- A 3D volumetric reconstruction of the jaw for the surgical guide
- A panoramic equivalent with higher resolution than standard OPG
Correct answer: A low-dose 2D overview image used to define the scan field of view before acquiring the full CBCT dataset
The scout view is a 2D planning image acquired prior to the CBCT scan that helps the clinician position and define the region of interest before capturing the full 3D dataset.
Question 5: Which pathological finding on a periapical radiograph adjacent to a planned implant site must be resolved before implant placement?
- Condensing osteitis of the cortical bone
- Well-defined periapical radiolucency indicating abscess or cyst (Correct answer)
- External root resorption on a distant tooth
- Hypercementosis on an unrelated molar
Correct answer: Well-defined periapical radiolucency indicating abscess or cyst
A periapical abscess or cyst appearing as a well-defined radiolucent lesion at a tooth apex adjacent to the planned implant site must be treated before implant placement to prevent contamination and failure.
Question 6: What is the clinical significance of the incisive canal when planning anterior maxillary midline implants on CBCT?
- It carries the infraorbital nerve and limits implant angulation in the anterior region
- It is a bony canal containing the nasopalatine nerve and vessels that can limit or prevent midline implant placement (Correct answer)
- It is used as a fixed landmark to measure bone height in the anterior maxilla
- It indicates the position of the anterior nasal spine for surgical orientation
Correct answer: It is a bony canal containing the nasopalatine nerve and vessels that can limit or prevent midline implant placement
The incisive canal houses the nasopalatine nerve and blood vessels in the anterior palate; CBCT assessment of its size and position is essential to avoid perforation during anterior maxillary implant placement.
CIT CIT Radiography & Imaging 2
Which maxillary anatomical structure must be carefully identified on CBCT before planning posterior maxillary implants due to its direct impact on available bone height?