maxillary antrum

Question 1

3 main fcts of paranasal sinuses

Answer 1

resonance to voice
reserve chamber for warming inspired air
reduce weight of skull

Question 2

embryology

Answer 2

form during 3rd and 4th foetal months
- evaginations of mucosa in nasal cavity
maxillary and ethmoid fairly large at birth
sphenoid and frontal - expansion during first few yrs of life

Question 3

opening - ostium

Answer 3

middle meatus (hiatus semilunaris)
opening approx 4mm diameter
located superiorly on medial wall of sinus
- position can predispose to sinusitis - hard to drain
lined with mucosa
can become narrowed/blocked during episodes of inflammation/disease

Question 4

differential diagnoses

Answer 4

dental
sinus
TMD
tumours
MS
atypical facial pain

Question 5

clinical significance

Answer 5

OAC/OAF
root in antrum
sinusitis
benign lesions
malignant lesions

Question 6

when should you suspect a malignant lesion?

Answer 6

when you can’t see walls of sinus

Question 7

which sinus is usually the largest?

Answer 7

MS

Question 8

shape of MS

Answer 8

pyramid

Question 9

dimensions of MS

Answer 9

av volumetric space 15ml in adult
37mm high
27mm wide
35mm AP

Question 10

what are generally found on the posterior wall of the sinus cavity and what is the clinical significance of this?

Answer 10

alveolar canals that transport the posterior superior alveolar vessels and nerves to the maxillary posterior teeth
can get referred pain e.g. pts think they have toothache

Question 11

MS and roots of molars and sometimes premolars

Answer 11

may project into the floor
roots may perforate the bone so that only the mucosal lining of the sinus covers them
if PA pathology could inflame the mucosa - can get mucosal thickening

Question 12

MS lining

Answer 12

pseudostratified ciliated columnar epithelium
cilia mobilise trapped particulate matter and foreign material within the sinus and move it towards the ostia for elimination into the nasal cavity

Question 13

diagnosis of OAC/OAF

Answer 13

size of tooth
radiographic position of roots in relation to antrum
bone at trifurcation of roots
bubbling of blood
nose holding test (careful as can create an OAC)
direct vision
good light and suction (echo)
blunt probe (careful as can create an OAC)

Question 14

OAC pre-op assessment purpose

Answer 14

so you can warn pt - explain it is a 2D image so roots may not be as close but there is a risk

Question 15

management of acute OAC if small or sinus lining intact

Answer 15

inform pt
encourage clot
suture margins
small OACs <2mm usually heal with normal blood clot formation and routine mucosal healing

Question 16

management of acute OAC if large or lining torn

Answer 16

close - if you can get primary closure not under tension without a flap then do it
BAF
- 3-sided - straight or slightly splayed for wider base
- need to release periosteum (fibrous, inelastic)
- paint line with scalpel where relieving incisions end
- once you have released it the flap becomes v elastic
so can cover socket w no tension
- non-resorbable (prolene)
- combination of sutures to keep it closed (mattress
sutures evert edges so get better healing as mucosa
not interrrupted

Question 17

acute OAC antibiotics

Answer 17

perforation introduces oral bacteria
use prophylactic antibiotics
7 days
amoxicillin or doxycycline

Question 18

acute OAC POIs

Answer 18

review appt in a couple of days
don't forcibly blow nose or stifle a sneeze (by pinching nose) - sneeze with mouth open
steam/menthol inhalation to keep sinuses clear
avoid using straw
no smoking
don't prod area
no vigorous mouthwashing
no wind instruments

Question 19

chronic OAF - pts may complain of

Answer 19

problems with fluid consumption (fluids from nose)
problems with speech/singing (nasal quality)
problems playing brass/wind instruments
problems smoking cigarettes/using straw
bad taste/odour/halitosis/pus discharge
- may need to squeeze/run blunt probe over
pain/sinusitis type symptoms

Question 20

management of chronic OAF

Answer 20

may need CBCT
excise sinus tract/fistula
 - if just close over it will reform
 - cut round it up to sinus then pull tube out, excavator for 
    remnants
antral wash out - remove all of the soft GT
BAF
buccal fat pad with BAF
palatal rotational flap
bone graft/collagen membrane
(tongue flap - historical)

Question 21

palatal rotational flap for chronic OAF

Answer 21

cut finger like projection of thick mucosa
leave attached and turn over the OAF
leaves raw bit on palate
- can make an acrylic healing plate to protect it while it heals

Question 22

fracture of maxillary tuberosity - aetiology

Answer 22

single standing molar (unsupported bone)
unknown UE molar/8
pathological gemination/concrescence
extraction in wrong order
 - create a last standing molar
inadequate alveolar support
 - have finger and thumb either side at all times
 - if needing too much force stop and do surgical

Question 23

fracture of maxillary tuberosity - diagnosis

Answer 23

noise
movement noted both visually or with supporting fingers
>1 tooth movement
tear on palate - sharp bone edges

Question 24

fracture of maxillary tuberosity - management options

Answer 24

dissect out and close wound

reduce and stabilise

Question 25

fracture of maxillary tuberosity - dissect out and close wound

Answer 25

if small don't just pull as you will rip may need a BAF

Question 26

fracture of maxillary tuberosity - reduce and stabilise

Answer 26

if large or have other teeth attached that you don't want to extract reduction - fingers (gauze) or gently w forceps - may need to disimpact it first fixation - needs to be rigid to get bony healing - if flexible splint will get fibrous healing (CT) - the more teeth you include the more rigid it will be (as you can only splint anteriorly) - ortho buccal arch wire spot-welded with composite (if can't get moisture control can use GI but harder to remove - (arch bar) - hard to get in and out and bad for PD health - splints - can get lab to make emergency splint - but need pt numb to take imp and cover area in vaseline so don't rip it out see pt in a couple of days to check splint

Question 27

fracture of maxillary tuberosity - remember to:

Answer 27

``` remove or tx pulp ensure occlusion free - reduce tooth to be extracted or soft splint to relieve ABs remove tooth 8wks later (SR) review next day ```

Question 28

fracture of maxillary tuberosity - POIs

Answer 28

antiseptics - cotton bud and CHX round splint soft diet painkillers baby toothbrush from next day

Question 29

root or tooth in MS - management

Answer 29

check not in suction/floor/on pt etc confirm radiographically by OPT, occ, PA (+/- CBCT) decision on retrieval - if can see/easy to get - risk pushing it further if in doubt or retrieval difficult - refer rarely may be tucked under intact mucosa, so not in sinus

Question 30

root or tooth in MS - retrival

Answer 30

OAF type approach/through socket - flap design - good light - open fenestration with care - may need bone nibblers and electric bur - suction - efficient and narrow bore - small curettes (discoid) - irrigation - ribbon gauze - soak it and gently pack into socket then pull it out and sometimes root comes out - close as for OAC Caldwell-luc approach - buccal sulcus - buccal window cut in bone ENT - endoscopic retrieval - go in through ostium and widen it to get root out

Question 31

sinusitis

Answer 31

sinus inflammation and infection

Question 32

why does sinusitis often present to the dentist first?

Answer 32

symptoms of pain and pressure in maxillary posterior teeth floor v close to root apices of maxillary posterior teeth - roots freq extend into sinus cavity

Question 33

sinusitis S+S

Answer 33

``` facial pain and pressure most freq congestion/fullness nasal obstruction paranasal drainage hyposmia fever headache dental pain halitosis fatigue cough (constant post-nasal drip) ear pain anaesthesia/paraesthesia over cheek ```

Question 34

aetiology of sinusitis

Answer 34

most commonly ppt by the effects of a viral infection - inflammation and oedema - obstruction of ostia - sinus can't empty - stagnation and trapping of debris within sinus cavity normal physiological fct further disrupted by the cellular damage that occurs to the mucosal lining - affects normal ciliary fct predisposing factors/mucociliary clearance patterns may be altered by: - allergens - inflammation - anatomic abnormalities - opening smaller/in different places when sinus can no longer evacuate its contents efficiently: - build up of pressure - opportune situation for bacterial overgrowth of normal flora

Question 35

sinusitis - important to rule out a dental cause

Answer 35

PA abscess PD infection deep caries recent ext socket TMD neuralgia or atypical facial pain/chronic midfacial pain facial pain in absence of obvious dental aetiology requires further investigation

Question 36

indicators of sinusitis and not toothache

Answer 36

discomfort on palpation of infraorbital region a diffuse pain in the maxillary teeth - can't identify which tooth equal sensitivity from percussion of multiple teeth in same region *pain that worsens with head or facial movements*

Question 37

aims of tx for sinusitis

Answer 37

tx presenting symptoms reduce tissue oedema - so pt can clear their sinuses reverse obstruction of the ostia

Question 38

tx for sinusitis

Answer 38

decongestants reduce mucosal oedema local measures first - humidified air - steam/menthol inhalations - go in and out so don't burn skin (ABs)

Question 39

decongestants for sinusitis

Answer 39

ephedrine nasal drops 0.5%, 1 drop each nostril x3 daily when required oxymetazoline (nasal spray)

Question 40

ABs for sinusitis

Answer 40

only if: - symptomatic tx is not effective/symptoms worsen/symptoms severe - S+S point to a bacterial sinusitis - purulent discharge lasting 7 or more days, bad taste, pus drainage down back of throat SDCEP - phenoxymethylpenicillin 250mg, 40 tablets, 2 x4 daily - doxycycline 100mg, 2 capsules on first day followed by 1 capsule daily for 7 days (if penicillin allergy or intolerance)

Question 41

foreign object in sinus

Answer 41

``` e.g. tooth, root, fractured endo instrument if retrievable remove at once if not - inform pt - take a radiograph - document in pt notes - place pt on appropriate meds - refer to OMFS or ENT ```

Question 42

fungal infections

Answer 42

v occ a non-resolving sinusitis may be due to a fungal infection can cause expansion of the bony walls by increased mucus secretion and fungal growth - fungal hyphae grow into walls hard to tx - sometimes need surgery

Question 43

trauma and iatrogenic factors

Answer 43

``` can cause sinusitis by violating the integrity of the bony cavity and sinus membrane sinus wall fracture orbital floor fracture RCT - initiate PA inflammation at floor of sinus - introduce bacteria into sinus - file pushed into sinus tooth ext - perforation - roots/tooth displaced into sinus dental implants/sinus lifts deep PD tx nasal packing NG tubes mechanical ventilation ``` = a perforation into the sinus will introduce oral bacteria therefore prophylactic ABs should be used

Question 44

benign lesions

Answer 44

polyps, papillomas, antral pseudocysts, mucoceles, retention cysts beware as an inverted papilloma has the potential to become malignant odontogenic cysts/tumours expanding into sinus - but grow so may need destruction surgery

Question 45

malignant lesions

Answer 45

primary tumours | local spread from adjacent sites