oms y3t3 Flashcards
majority of infections due to what kind of bacterial
aerobes
anaerobes (will eventually be the predominant species)
streptococcus (Alpha hemolytic)
what is pathway of spread of infection affected by
- thickness of overlying bone at apex: drainage of infections spread through path of least resistance
- rship of perforation of bone to underlying mm attachment: higher than mm attachment = sinus opening at skin. lower than mm attachment = intra oral
ludwig angiina
aggressive rapid spread of cellulitis involving subL submd submn spaces
complications: airway obstruction, dysphagia, spread to other spaces
pri vs sec oral candidiasis
pri - condition is confined to mouth and peri oral tissue
sec - the oral candidiasis is just an oral manifestation of systemic mucocutaneous candidiasis
tx of candida
nystatin swish, *cannot give w chx
clotrimazole (oral)
which tissue can regenerate
only bone regenerates, all other tissues heal by scar
definition of dental implants
implants are perimucosal device which are BIOCOMPATIBLE AND BIOFUNCTIONAL and is placed within mucosa or bone in the oral cavity to provide support for fixed or removable prosthesis
definition of osseo integration
a TIME DEPENDENT healing process whereby clinically asymptomatic rigid fixation of alloplastic material is achieved and maintained during functional loading
factors that affect OI
- implant biocompatibility
- implant design
- implant surface
- implant bed
- sx technique
- loading conditions
attachment on natural tooth vs on implants
both have unbroken perimucosal seal between soft tissue and tooth surface / implant abutment surface
natural tooth: hemidesmosomes + PDL
implants: hemidesmosomes (LJE) only
parts to an implant crown
- crown (prosthetic)
- abutment
- titanium post (fixture)
titanium alloy
tit-6-alu-4-vanaium
what is steady state bone response
bone reso = bone depo
what is “pitch” of an implant
pitch = the no. of threads per unit length
increased pitch and depth btwn individual threads allow for improved contact area btwn bone and implant
which type of bone is best for implant success
type 2 bone: thick layer of cortical bone surrounding dense trabecular bone
usually found in lower posterior jaw
takes ~4mth to OI
features that are essential to proper implant sx
- careful cooling of sx drill to prevent bone from heating up
- using sharp drills
- using graded series of drills that gradually increase in diameter
- proper drill geometry
- moderate lvl of insertion torque
what is fibro osseous integration
tissue to implant contact w dense collagenous tissue btwn implant and bone. presents as being clinically firm but over time due to masticatory mvmt, more fibrous tissue forms, poor LT success
some complications of implants
peri implantitis
penetration of sinus
implant loosen drift into sinus
aesthetic poor
fractured implant component
perforation of anatomical structures
best time to book medically complicated pt
morning!!!
what are 3 components of gasgow coma scale
eye opening
motor
verbal
le fort fracture pattern tend to cause hematomas where
at the junction of hard and soft palate
sublingual hematoma is characteristic of
md fractures (particularly parasymphysis)
what xrays for mx fracture
occipittomental view (aka waters view)
OPG
what xrays for md fracture
lateral oblique
towne’s view
occlusal
xrays to take for condylar fracture
reverse townes
pos-ant of skull
opg
most common etiology of facial fractures
road traffic accidents
most common site of md fraacture
body of md
sub condylar
classification of type of fracture:
1. green stick
2. simple
3. comminuted
4. compound
- greenstick: incomplete separation at the fracture
- simple: complete separation, minimal fragmentation
- fractured bone is in multiple segments
- communication of margin of fractured bone w external envt
favourable vs unfavourable fracture
favourable = less displacement of fractured part when mm pulls
unfavourablel = mm pull results in more displacement
closed reduction vs open reduction
closed - any tx that doesnt involve open sx exposure of fracture
open - sx access is required
what does lindahl’s classification of condylar fracture include
- fracture level (which part of condyle)
- rship of condylar fragment to md
- rship of condylar head to fossa
unilateral effusion / hemarthrosis of condyle
ipsilateral POB
midline shift away
unilateral fracture + dislocation
premature contact + midline shift towards
bilateral fracture + dislocation
AOB, loss of ramus height
bilateral dislocation wo fracture
md prognathism, inability to ocl
when is ORIF required
- condylar displaced into middle cranial fossa
- inability to obtain adequate ocl by closed reduction
- foregin body
- lateral extracapsular displacement of condyle
- bilateral condyle fracture in edentulous pt when splinting is impossible
presentation of le fort 1 fracture
AOB, split palate, swelling, increased LAFH, epistaxis (nose bleed)
presentation of le fort 2 fracture
AOB, hypertelorism (eyes further apart), periorbital ecchymosis, subconjunctival hemorrhage, epistaxis
presentation of le fort 3 fracture
AOB, diplopia, periorbital ecchymoses, flattening of cheeks, subconjunctival hemorrhage, tilting of ocl plane
how to tx midface fractures when ocl is affected
- reest proper ocl rship w md
- IMF
- anatomical reduction + stabilisation of fractured site (direct wiring, bone plates)
how to tx mid face fractures when ocl is not affected
- open reduction e/o or i/o
- small bone paltes or wiring to stabilise
principles of tx for fractures
- reduction
- immobilisation
- fixation
- rehabilitation
- restore previous injury form and fn
- precise hard tissue repair
- soft tissue redrape
- restore volume, aesthetics
load bearing vs load sharing plates
load sharing: monocortical screws. plate and bone share the functional loading
load bearing: bicortical screws
when to used closed reduction
- minimal displacement
- comminuted fractures
- able to obtain pre injury ocl
- pt refuse orif
- no impairment of fn
what is imf
est a proper ocl rship by wiring teeth tgt
- pre fab arch bars
- ivy loops
benefits of orif
orif = there is an internal rigid fixation
- direct visualisation of fragments for accurate reduction and fixation
- better comfort and convenience bc not need IMF for so long
- better post op nutrition & hygiene
- better general post op mx of pt w multiple injuries
- early md metabolism –> early restoration of normal jaw activity
what is used for md fixation
- ti bone plates, screws
- wires, elastics, arch bars,
when is orif not indicated, e/o fixation indicated instead
- infection v severe, pt have trismus, comminuted fractures (nothing to plate tgt)
steps for ORIF
- put teeth into ocl with imf or hold in place
- make incision to expose fracture
- reduce by manipulating anatomy
- fixation by putting plates & screws (at least 4)
- release IMF (but may be kept on if still needs IMF for stability and guidance)
- check ocl
- closure of incision
risk of IMF
PT IS AT RISK FOR tmj ankylosis or fibrosis or severe limited mouth opening. do not imf for >2 weeks
minimum buccal lingual width of bone for implants
at least 1mm of bone surrounding implants
