Selction criteria Flashcards Preview

Year 3 Radiography > Selction criteria > Flashcards

Flashcards in Selction criteria Deck (46)
Loading flashcards...
1
Q

how to justify taking radiographs

A

is it going to change diagnosis/management of pt

2
Q

5 reasons to take x rays

A
  • pathology affecting tooth or supporting structures
  • require knowledge of root or pulpal morphology
  • unerupted teeth present
  • screening for caries
  • localisation of teeth/foreign bodies
3
Q

name 3 intraoral views

A

bitewings
periapicals
occlusal views

4
Q

name 2 extra oral views

A

dpt/oblique lateral view

lateral cephalometric view

5
Q

5 indications of bitewings

A
  • caries detection
  • caries monitoring
  • assessing restorations
  • vertical bitewing –> perio pockets up to 6mm
6
Q

what type of caries are bitewings most useful for

A

interdental, not clinically evident

7
Q

by how much do posterior bitewings improve caries diagnosis

A

x4

8
Q

2 problem of using x rays to diagnose caries

A
  • requires 50% demineralisation (so caries always bigger than on x ray)
  • need good contrast between enamel and dentine
9
Q

how to get good contrast on x ray

A

lower kV

10
Q

when is less contrast needed for bitewings

A

assessing perio pockets (so higher kV)

11
Q

european association for paediatric dentistry guidelines of bitewing frequency

A

only is necessary for adequate tx

  • 5yo
  • 8-9yo
  • 12-14yo (after eruption of premolars and 2nd molars)
12
Q

intervals between bitewings for pt with

a) low caries risk
b) high caries risk

A

a) low caries risk: 3 yrs

b) high caries risk:1 year

13
Q

4 uses of periapical radiographs

A
  • root/pulpal pathology or development
  • extent of crown pathology in anterior teeth
  • assessment of apical pathology
  • assessment of local anatomy including tooth development
14
Q

2 techniques of periapicals and which is better

A
  • long cone paralleling (better)

- bisecting angle(worse, pt can move film in the mouth, difficult to align)

15
Q

5 types of occlusal radiographs

A
  • upper standard (nasal occlusal, large bisected angle periapical)
  • upper oblique occlusal
  • lower 90 degree occlusal
  • lower 45 degree occlusal (large bisected angle periapical)
  • lower oblique occlusal
16
Q

4 reasons to use upper standard occlusal

A
  • unable to take periapical view
  • trauma (pt cannot take film in mouth)
  • palatal pathology
  • 2nd view to aid localisation of canines
17
Q

2 reasons to use upper oblique occlusal

A
  • unable to take periapical or bitewing

- provide view from different angle

18
Q

4 reasons to use lower 90 degree occlusal

A
  • salivary calculi (lower exposure)
  • fracture of anterior mandible
  • bucco-lingual expansion of cortical bone
  • localisation
19
Q

3 reasons to take lower 45 degree occlusal

A
  • unable to take periapical
  • lesion too large to visualise on intraoral
  • anterior fracture of mandible
20
Q

2 reasons to use lower oblique occlusal

A
  • cannot tolerate periapical

- imaging submandibular gland

21
Q

can x rays diagnose perio? explain

A

no. must do clinical examination (eg 6pppc)

22
Q

4 uses of radiographs in perio

A
  • assess bone loss/furcation
  • determine presence of causative factors
  • assist in treatment planning
  • evaluate tx
23
Q

guidelines for which radiographs to use for which pocket depth in perio

A
  • 4-5mm pocket (BPE 3): horizontal bitewings
  • 6mm+ pockets (BPE4): vertical bitewings/paralleling technique periapicals
  • irregular pocketing: bitewings (horizontal/vertical) and paralleling technique periapicals
24
Q

2 reasons why periapicals are better than DPT perio

A
  • DPT shows all teeth BUT distorts level of bone

- periapical (even full mouth) has lower dose

25
Q

type of x ray used if perio/endo lesion suspected

A

paralleling technique periapical

26
Q

when/what to radiograph for endo

A
  • pre-op: periapical to determine working lengths
  • prior to condensation of GP if doubt in integrity of apical construction
  • immediately following obturation (baseline and quality)
  • asymptomatic teeth: 1yr and 4yrs after tx
27
Q

when you may need to retake radiograph for endo

A

if preset file is >2mm from radiographic apex

28
Q

when to radiograph with trauma

A
  • all but minor trauma

- review radiographs (depending on damage)

29
Q

when to take DPT with trauma and why

A

mandibular fracture and additional supporting views (need bucco-lingual view to assess displacement)

30
Q

average amount of filled teeth in UK dentate adult

A

7

31
Q

% adults with at least 1 crown

A

34%

32
Q

% adults with >6 crowns

A

5%

33
Q

when/what to take radiographs with cons

A

periapical (using beam aiming device) before any crown/bridge/denture prep

34
Q

guidance for follow up radiographs of crowned teeth

A

based on clinical judgement

use posterior bitewings

35
Q

when to use DPT 7

A
  • prior to dental surgery under GA (eg tumour removal)
  • where bony lesion/unerupted tooth is of a size/position which precludes its complete demonstration on intraoral radiographs (eg too posterior)
  • prior to clearance/multiple extractions where clinical decision to remove teeth has already been made (eg bc teeth are wobbly)
  • ortho assessment
  • trauma
  • as part of assessment of periodontal bone support where pockets >6mm and no other radiographs available
  • implant assessment
36
Q

when may oblique lateral radiography be used

A
  • when pt cannot tolerate intraorals, eg special needs/ children
  • TMJ dysfunction (if history of trauma/unusual symptoms, otherwise clinical diagnosis is fine)
  • assessment of condylar head
37
Q

when to use DPT screening

A

NEVER. too high dose

38
Q

4 uses of lat ceph radiographs

A
  • assess skeletal pattern
  • angulation of incisors
  • orthognathic surgical planning
  • lat ceph tracings (measures discrepancies/skeletal profile)
39
Q

when to use skull views

A

assess trauma to mandible

40
Q

what x rays to use for complicated/severe skull fractures and why

A

CT scan. can see bone and soft tissue (brain)

41
Q

when is ultrasound used

A

head/neck lumps

salivary gland disease

42
Q

pros/cons of ultrasound

A

safe, quick, effective BUT v operator dependent

43
Q

when to use sialography

A

obstructive salivary gland disease to demonstrate strictures and stone mobility

44
Q

when to use MRI

A

soft tissue lesions eg salivary tumours/cancer of head and neck

45
Q

when to use nuclear medicine

A

(rare) TMJ hyperplasia

46
Q

how nuclear medicine works

A

radioisotopes injected –> gamma camera detects radioactivity eg areas of high bone turnover