tys shen ti

Question 1

factors to consider when about to do a laop for wisdom tooth if we are afraid of risk of IDN

Answer 1

PATIENT FACTORS
1) local anatomy - relationship between canal and roots.
- root: darkening, deflection, narrowing of root, bifid root apex
- canal: diversion, narrowing, interruption in white line of canal

2) depth of impaction
- deeper means associated with higher injury rate

3) pre existing regional pathology eg presence of cyst that erodes bony plates

4) age: correlation betweeen increasing age and incidence of IDN injury

SURGICAL FACTORS
1) experience of surgeon
2) surgical technique used
3) type of access - lingual flap increase risk of lingual n damage

Question 2

mx of pain and swelling following an impacted 3M surgery

Answer 2

1) assure patient that pain and sewlling is expected post op for 2-3 days, even up to 5 days. if it has been longer than that, wound site might be infected and hence secondary bleeding, call patient in to redress wound

2) obtain hx of pain

3) check patients compliance with POI

4) check medication that is given and reconfirm MH to see if there are any possible complications

5) e/o exam: extent of swelling, involvement of fascial spaces, compromise to airway?

6) i/o examine wound site
ddx: AO, remnant fragment not removed, FB

7) retreat
- suture, recall

Question 3

possible spread of odontogenic infection from a grossly carious max canine

Answer 3

opening: talk about odontogenic infection spreading through path of least resistance and hence infect anatomic spaces between orofacial structures that are closely related to the affected tooth

1) canine space
- abscess erodes through the bone superior to the insertion of the levator anguli oris
- canine space is between levator anguli oris and levator labii superioris
- sign: swelling that obliterates the nasolabial fold
- if untreated infection will drain via medial or lateral canthus of eye

• if its very bad, will erode into infraorbital vein or inferior opthalmic vein and hence there is spread via common opthalmic vein into cavernous sinus = CST

Question 4

POSSIBLE spread of infection from mandibular 1M

Answer 4

1) submand space which is a fascial space located on superficial surface of mylohyoid muscle between anterior and posterior bellies of digastric muscle
- roots of posterior teeth likely to be below mylohyoid than above, thus odontogenic infections spread towards submand space

signs:
- trismus
- inability to palpate mandibular border
- swellign over submand region

Question 5

clinical findings that would differentiate swelling secondary to surgical trauma from that of an infection

Answer 5

1) S&S
- surgical cause will not have systemic side effect but if its infection then fever, malaise, high pulse rate

2) characteristics of swollen appear
- infection more likely to be warm, red, pain, but depends on whether its cellulits or abscess
- cellulitis can say indurated vs fluctuant in abscess
- cellulitis is generalised diffuse pain, abscess is localised pain

3) duration
- surgical swelling will subside on 3-4th day but infection wont subside on its own

Question 6

procedure for i&d

Answer 6

• LA away from site of infection
• prep for pus culture (large gauge needle, 2ml syring, aspirate 1-2ml of pus)
• incise with no 11 blade (<1cm long)
• use tweezers to break up loculations/ cavities of pus that have not been opened by initial incision
• suck out pus
• place drain (1/4 inch sterile penrose drain for 2-5days)

Question 7

considerations in diabetics

Answer 7

1) might have renal involvement
- fbc
- renal panel

2) anesthesia
- avoid NSAIDs because certain ones can potentiate hypoglycemia (eg patient taking SUF like glipizide)
- nsaids also reduce clearance of metformin bc nsaids impair renal function

3) monitor for signs of hypoglycemia, standby dextrose

Question 8

different types of wounds and what is the AB regimen

Answer 8

1) clean
- uninfected wound without inflammation
- respiratory, alimentary, genital, urinary tracts not entered

2) clean/contaminated
- operative wounds in respiratory, alimentary, genital or uninfected urinary tracts entered, no unusal contamination

3) contaminated
- open and fresh wounds
- major breaks in sterile technique, gross spillage from GIT

4) dirty
- old wounds with devitalised tissue
- or those involving clinical infection or perforated viscera

no AB needed for clean, AB as prophylaxis for clean contaminated, AB as tx for contaminated and dirty

Question 9

ddx for white patch on lateral bordr of tongue

Answer 9

1) frictional keratosis

2) OLP

3) Licehnoid reactions to amalgam restorations

4) leukoplakia

5) Oral hairy leukoplakia

Question 10

what are some features of ORIF

Answer 10

fixation is the immobilisation of bony fragments at the fracture site

• ORIF is the tx of choice in facial fractures
• plates and screws are cornerstone of ORIF
• include reconstruction plates, also referred to as load bearing plates
• or compression plates which have the ability to compress fractured bone margins and allow better stability and interlocking

screws can be monocrotical or bicortical
- monocortical screws only engage the buccal bone cortices
- bicortical screws engage both the buccal and lingual bone cortices, bicotical screws also provide compression
- lag screws are used to compress fracture segments without the use of bone plates, are placed perpendicular to the line of fracture

different forms of fixation
- load bearing vs load sharing

1) load sharing: means that load is shared with bone on each side of the fracture
- simple linear fractures are treated like this

2) load bearing:
- have to provide fixation of sufficient strength and rigidity that it can bear the entire load of the mandible