Third molar assessment Flashcards
for third molars, what age is the
- crown completed
- roots completed
- eruption
Crown completion 12-16 yo
Roots completed 18-25 yo
Eruption approx 19-20 yo
what problems can eruption of third molars cause
what can these issues lead to
failure of eruption/partial eruption/ectopic development
-> abnormal positioning of tooth
impaction against adjacent tooth
-> food packing
-> distal cervical caries
-> root resorption in the second molar
-> soft tissue pathology such as cysts
what do you use to classify the types of third molar impaction for a patient
diagnostic evaluation of radiographs
what are the 4 types of impaction in mandibular third molars
mesioangular (mesially-tilted) -> MOST COMMON IN MANDIBLE
horizontal (perpendicular to adj tooth) -> MOST COMMON IN MANDIBLE
vertical (almost parallel to adj tooth)
distoangular (distally-tilted)
what are the 3 types of impaction in maxillary third molars
mesioangular (medially-tilted)
vertical (almost parallel to adj tooth)
distoangular (distally-tilted) -> MOST COMMON IN MAXILLA
What is the difference between a symptom and a sign
Symptom- an indication of disease noticed by a patient
Sign- observations by a health professional indicating disease or disorder
List 4 examples of signs that can occur in third molars
pathological pocket depth
bleeding on probing
tenderness on palpation
radiographic features
List 4 examples of symptoms that can occur in third molars
pain
swelling
bad breath
difficulty chewing
- what is pericoronitis
- what is it caused by
- rarity
- an infection of the soft tissue around the crown of a partially erupted tooth
- usually caused by normal flora n
- common
what problems can occur in partially erupted/unerupted third molars
- pericoronitis
-> if untreated can lead to infection - caries
- pathology (cysts/tumours)
- resorption
- trauma
- orthognathic surgery
5 factors making you susceptible to pericoronitis
- Compromised host defences e.g. diabetes/medication
- ‘Trauma’ – often from opposing dentition
- Food trapping under the operculum
- Bacterial infection
- Poor oral hygiene
Which 3 bacteria are involved in pericoronitis
- Prevotella intermedia
- Fusobacterium species
- Anaerobic streptococci
5 local symptoms of pericoronitis
pain
halitosis
swelling
erythema
bad taste
5 systemic symptoms of pericoronitis (caused by progression of local symptoms)
trismus - difficulty opening mouth
pyrexia - raised body temperature
lymphadenopathy - (localised) swelling of lymph nodes
malaise - feeling sick
dysphagia - difficulty swallowing
3 local measures to manage pericoronitis
- irrigation with saline/chlorhexidine
- oral analgesia (paracetamol/NSAIDs if no C/l)
- oral rinse (warm salt water/CXD mw - check sensitivities)
what is the issue with using chlorhexidine for irrigation as a local management technique
can cause anaphylactic reaction
5 systemic measures to manage pericoronitis
- ABCDE
- Irrigation with saline
- Oral analgesia (paractemol / NSAIDs if no C/I)
- Oral rinse warm salt water / CXD m/w – check sensitivities
AND - Broad spectrum antibiotic for 5/7 days
what broad spectrum antibiotics can be taken for managing pericoronitis
how often should you take them
Amoxicillin 500mg TDS (3)
Penicillin V 500mg QDS (4)
Metronidazole 400mg TDS (3)
list an overview on how to assess for pericoronitis
c/o
history- socrates, MH
examination - EO, IO
investigation - vitality testing, radiographs
diagnosis
tx plan
what 3 different factors are important when assessing for pericoronitis
patient factors
surgical factors
operator/environment factors
8 patient factors you need to consider when assessing for pericoronitis
age
social history
medical history
drug history
BMI
ethnicity
capacity
anxiety
why is age an important patient factor when assessing for pericoronitis
Increased morbidity with age
- physiological changes
- co-morbidities
- recovery period (older=longer)
- after 24yo complications with third molars increases significantly
why is social history an important patient factor when assessing for pericoronitis
Smoking, vaping, alcohol, diet - all affect healing
Occupation - long term deployment
Access to care
Post-operative care
why is drug history an important patient factor when assessing for pericoronitis
Steroids
Bisphosphonates
Biologics / Immunomodulators
Antiplatelets / Anticoagulants
affects healing/treatment/prognosis
why is BMI an important patient factor when assessing for pericoronitis
- higher BMI increases risk of diabetes, hypertension, CVD
- people with higher BMI tend to have smaller mouths, therefore access is more difficult
why is ethnicity an important patient factor when assessing for pericoronitis
afro-carribean tend to have denser bone
why is capacity an important patient factor when assessing for pericoronitis
patients need capacity to consent for treatment
- why is anxiety an important patient factor when assessing for pericoronitis
- how can you measure anxiety of a pt
- more anxious pt=more difficult to tx
- can measure anxiety with MDAS questionnaire
6 surgical factors to consider when assessing for pericoronitis
third molar
periodontal status
surgical anatomy
mouth opening
adjacent structures
associated pathology
why is the third molar itself an important surgical factor when assessing for pericoronitis
Can assess the clinical picture to see if
-> fully erupted/partially erupted
-> presence/absence of disease/infection
Helps with the early formation of a differential diagnosis
why is imaging important when assessing for pericoronitis
Appropriate radiographic interpretation is used in combination with clinical information and other tests to formulate a differential diagnosis
why is surgical anatomy an important surgical factor when assessing for pericoronitis
Inferior alveolar nerve - enters the mandible through the mandibular foramen, runs through the mandible from lingual to buccal and exits through the mental foramen- and supplies sensation to lower teeth gums, lower lip and skin of the chin
Inferior alveolar artery- likely runs posterior/postero-lateral to IAN
Inferior alveolar vein - no pattern can be 2 veins, lateral to the bone
Lingual nerve- runs alongside IAN but is superficial to it, supplies sensation to tongue and corded tympany (supplies taste to the tongue)
-> can sit high in soft tissues sometimes so need to be careful distal to mandibular third molar and lingual to the bone
Facial nerve
Trigeminal nerve
Need to be able to assess relationship of the apices of the tooth to the maxillary sinus
what does it mean if you start to see blood pooling in the base of a mandibular third molar socket
very close to the nerve
Acronym to report abnormal findings on radiographic imaging
SSSTOP
Site
Size
Shape
Translucent/opaque
Outline
Previous imaging (for comparison)
Name 4 red flags on radiographic imaging
- Loss of symmetry / apparent soft tissue mass
- Distorted anatomy – displaced teeth
- Bone erosions – look at anatomical margins
- Teeth ‘floating’
10 things to include on a radiographic report
➢ Presence of caries
➢ Condition of existing restorations
➢ Alveolar bone levels
➢ Root morphology
➢ Morphology of pulp chamber
➢ Signs of periodontal pathology
➢ Position of unerupted teeth or retained roots
➢ Other pathology of the jaws
➢ Form and quality of edentulous ridge and underlying bone
➢ Boundaries of relevant anatomical features
4 aspects to particularly look at when reporting radiographic imaging for third molars
➢ Relationship to vital structures
➢ Configuration of roots
➢ Condition of the surrounding bone
➢ Apical e.g. pathology
What are 4 vital structures near to mandibular third molars
lingual nerve
long buccal nerve
mylohyoid nerve
inferior alveolar nerve
name 2 vital structures near to maxillary third molars
maxillary tuberosity
maxillary antrum
7 high-risk abnormalities you may see on third molars on a plain-film radiograph
dark and bifid apex of root
deflection of root
narrowing of root
narrowing of canal
darkening of roots
interuption of white line of canal
diversion of canal
if you see any of the 7 abnormalities on a plain-film radiograph
considered an intimate relationship
consider doing cone CBCT to visualise further
- What is a CBCT
- Advantage of doing CBCT over plain-film radiograph
Advanced Cone Beam CT
plain film=2D, CBCT=3D imaging in coronal, sagit tal and axial planes
What must be done before carrying out a CBCT
- must be justified on an individual basis by demonstrating that the benefits to the patients outweigh the potential risk, images should potentially add new information to aid the patients management
- history and clinical examination have been performed
‘routine’ imaging is unacceptable practice
when assessing roots what 5 factors should you look at
➢ Number
➢ Curvature
➢ Degree of root divergence
➢ Size and shape of roots - bulbous, conical, long, short, hooked
➢ Other - root resorption, caries, ankylosis
what is the difference in the bone of younger (e.g. <18yo) and older (e.g. >35yo) patients
Younger:
- Less dense
- Pliable
- Expands
- Bends
- Easier to cut / expand
Older:
- Much denser bone
- Decreased flexibility
- Decreased ability to expand
- More bone removal required
- Higher risk of fracture
what does bone density determine in terms of extractions
difficulty
denser = more difficult
why is access an important surgical factor when assessing for pericoronitis
good access to site=easier to operate
why is depth of impaction an important surgical factor when assessing for pericoronitis
the deeper the impaction, the more complex the procedure
name 11 factors that can increase the risk of complications with third molars
- Underlying systemic disease
- Increased age
- Infection
- Anatomical position of tooth/root morphology
- Local anatomical relations
- Status of adjacent teeth
- Reduced access
- Dense bone
- Lack of PDL space – ankylosis
- Pathology
- Poor patient cooperation/compliance
what is an operculum
a gum tissue flap covering a partially erupted wisdom tooth
