Dental Radiographs Flashcards
Name the abnormality that is shown in the tooth below:
Supernumerary root of the mandibular 4th premolar
Compare and contrast when the parallel and bisecting angle techniques of teeth radiography should be used:
- Parallel technique - useful for mandibular molars and premolars
- Bisecting angle technique - all teeth in the mouth
Describe the principle of a parallel X-ray technique:
Describe how the bisecting angle technique is performed:
- Used where the film cannot be placed parallel to the long axis of the tooth
- Shoot perpendicular to the bisecting angle
What are the standard radiographic projections?
- Rostral maxillary
- Rostral mandibular
- Right & left maxillary: may need one cranial and one caudal
- Right & left mandibular: may need one cranial and one caudal
Describe how you would take the 6 radiographic projections?
- Right maxilla: Animal in VR - 45 degree bisecting from the right side
- Maxillary incisors: Animal is in VR - 55 degree angle from dorso-ventral angle
- Left maxilla: Animal in VR - 45 degree bisecting angle from the left hand side
- Left mandible: Animal in DR - 45 degree bisecting angle from left hand side
- Mandibular incisors: Animal in DR - 55 degree from horizontal
- Right mandible: Animal in DR - 45 degree angle from the horizontal
Name the process that is shown in the image below:
Palatine processes of the maxilla
Name the structures that are shown in the mandible below:
- Mandibular canal
- Mental foramina
Name the radiographic feature that is shown below:
- Middle mental foramina
Name the radiographic feature that is shown in the X-ray below:
Chevron - normal radiolucency @ the base apex - non-diseased tooth (common in maxillary incisors, maxillary canines and mandibular molar 1)
Name the features that are shown in the radiograph below:
- Chevron - normal radiolucency apically on the tooth
- Cervical burn out - @ neck of tooth - more radiolucent due to thinning of the enamel just above the start of alveolar bone
Name the structure that is shown in the image below:
Mandibular canal
Name the structures that are shown in the diagram below:
- Palatine fissure
- Incisive canal
- Chevron
Describe the appearance of deciduous teeth:
- Relatively smaller
- Less radio-dense than permanent
Describe the structure of the normal young adult tooth:
- Dentine is thin → secondary dentine is laid down as animal ages
- Pulp chamber is large
- Initially the root apex is open → as animal ages will close in 9-12 months
- Lamina dura is quite distinct
Compare the canines in the cat to the dog:
Canine is much straighter in a dog compared to a cat
Describe the four normal features of periodontal anatomy that should be seen in the teeth:
- Crestal bone - should be close to CEJ (approximately 2mm apically) - normally a pointed angle
- Lamina dura - dense lining of alveolus - seen as a white line
- Periodontal ligament - appears as a black line
- Furcation - present right into furcation
What are the four stages of alveolar bone loss and what would you expect to see with each in terms of bone loss?
- 1: Gingivitis, no attachment loss
- 2: Mild <25% alveolar bone loss
- 3: Moderate 25-50% alv bone loss
- 4: Severe > 50% alv bone loss
How much bone loss must occur for radiographic signs of periodontal disease to become apparent?
40% of the bone must be lost for it to be visualised on Xray
Name the two features that comprise attachment loss:
- Attachment loss
- Gingival recession
- Periodontal pocket
Attachment loss = gingival recession + periodontal pocket depth in mm
Describe the features that you would expect too see in Stage 0 Periodontal disease:
- Clean crowns
- Tartar is starting to develop
- Gum margins are flat and pink → creates a scalloped edge against teeth
- Bone levels are just under the bulge of crown (NO BONE LOSS)
What are the clinical signs seen in Stage 1 periodontal disease?
- Build up of tartar and slightly reddened/swollen gums (NO BONE LOSS)
What is seen radiographically in Stage 2 periodontal disease?
0 - 25% bone loss - fuzzy where it should be sharp
What is seen in Stage 3 periodontal disease?
25-50% bone loss has occurred
What percentage of bone loss is seen in Stage 4 periodontal disease?
Greater than 50% bone loss
What is typically observed in periodontitis?
Horizontal and vertical bone loss
What are the radiographic signs of endodontic disease that may be seen?
- Disrupted crown
- Widening of endodontic canal
- Internal reabsorption
- Periapical lucency - bulbous w/lack of lamina dura
Name the radiographic abnormality shown in the image below?
- Periapical lucency
Name the type of tooth resorption that is shown in the image below:
Type 1 tooth resorption
Name the type of tooth resorption that is shown below:
Type 2 tooth resorption
Name the type of tooth resorption that is shown below:
Type 3 tooth resorption
Name the condition that is shown in the radiograph below:
- Hypercementosis - thickened cementum (often apical 3rd - makes extraction more difficult)
What are the four main types of cysts that can occur in teeth?
- Dentigerous cyst - unerupted tooth especially mandibular premolar 1 (Boxers)
- Radicular cyst - from endodontic disease
- Primordial cyst - degeneration of tooth bud
- Odontogenic tumours
Name the most likely type of tumour shown in the radiograph below:
Peripheral Odontogenic Fibroma - ossifying type (no invasion of bone)
Name the most likely type of tumour demonstrated in the radiograph below:
Ancathomatous ameloblastoma - local invasion of the mandible - slow growth resulted in teeth being pushed apart
Name the most likely neoplasm in the mouth of the dog shown below:
SCC -→ leading to destruction of the mandible
