maxillary sinus

Question 1

sinuses in the face

4

Answer 1

frontal sinus
sphenoid sinus
ethmoid air cells
maxillary sinus (dental most concerned)

Question 2

embryology of sinuses

3

Answer 2

Formation occurs during 3rd and 4th foetal months, with evaginations of the mucosa of the nasal cavity

Maxillary and ethmoid relatively large at birth

Sphenoid and frontal undergo expansion within the first few years of life

Question 3

3 functions of paranasal sinuses

Answer 3

• resonance to the voice
• reserve chambers for warming inspired air
• reduce the weight of the skull

Question 4

maxillary sinus a.k.a

Answer 4

maxillary antrum

Question 5

maxillary sinus anatomy

and dimensions

Answer 5

Usually, the largest of the sinuses

Pyramid-shaped cavity within the body of each maxilla

Volumetric space 15ml in average adult

Average dimensions: variation between people
* 37mm high
* 27mm wide
* 35mm antero-posteriorly

Question 6

opening of the maxillary sinus (ostium)

5 points

Answer 6

Middle meatus (hiatus semilunaris)

Opening approx. 4mm diameter

Located superiorly on medial wall of sinus (large collection of fluid/mucous before it can drain)

Lined with mucosa

Can become narrow or blocked during episodes of inflammation/disease easily

Question 7

posterior wall of maxillary sinus has

Answer 7

alevolar canals that transport the posterior superior alveolar vessels and nerves to the maxillary posterior teeth

Question 8

maxillary sinus and roots of maxillary teeth

Answer 8

Roots of maxillary molars and sometimes premolars may project into the floor of the maxillary sinus

The roots may perforate the bone so that only the mucosal lining of the sinus covers them

Question 9

epithelium of sinuses

Answer 9

pseudostratified ciliated columnar epithelium (produce mucous)

Question 10

role of cilia in epithelium of sinuses

2

Answer 10

• mobilise trapped particulate matter and foreign material within the sinus
• move this material towards the ostia for elimination into the nasal cavity

pseudostratified ciliated columnar epithelium

Question 11

ostia/ostium

Answer 11

opening of sinus

Question 12

6 possible clinical issues that can occur to msaxillary sinuses

Answer 12

• Oro-Antral Communication (OAC) - Acute
• Oro-Antral Fistula (OAF) - Chronic
• Root in the antrum
• Sinusitis
• Benign Lesions
• Malignant Lesions

Question 13

most common clinical issues involving maxillary sinus

Answer 13

OAC/OAF

Question 14

aetiology of OAC/OAF

Answer 14

Extraction of toot/RR and due to close relation of floor maxillary antrum/sinus and tooth create a communication either by breaking bone of floor or ripping the mucosa lining and oral cavity(previously wasn’t there)
* Get bacteria ingress into sinus
* Affect function of sinus

Question 15

how to dx OAC/OAF

7 main

Answer 15

• Size of tooth
• Radiographic position of roots in relation to antrum predict
• Bone at trifurcation of roots possible to come out in extraction
• Bubbling of blood
• Nose holding test gently - careful as can create an OAC; if just broken bone, lining can be intact and this can break it
• Direct vision
• Good light and suction – echo sound

Blunt probe (take care not to create an OAC) avoid

Question 16

pre op assessment for risk OAC

3 indications from radiograph

Answer 16

close radiographic relation between roots and antrum

Loan standing upper molar has increased chance of communication and/or # tuberosity

Splayed roots increased chance

Arrow area – 26 can see maxillary sinus has been wrapped around the roots (less so on 16), very little bone – high chance communication and # tuberosity

Question 17

OAC is

Answer 17

acute
just happened, immediate post extraction - can see bleeding, potential prolapse of lining of maxillary antrum

Question 18

OAF is

Answer 18

chronic

communication made - management failed and opening persists - sinus tract has been created now

no bleeding

Question 19

management of OAC

Answer 19

Inform patient

If small or sinus lining intact: majority
* Encourage clot
* Suture margins pack has risk of pushing into sinus
* Antibiotic (area of debate)
Post-op instructions most important
* Minimising pressure formation within the sinuses and mouth
* Avoid blowing nose, avoid sucking through straw, inflating balloon, smoking, avoid singing

Small OACs <2mm usually heal with normal blood clot formation and routine mucosal healing

If large or lining torn: Close with buccal advancement flap

acute

Question 20

prognosis of OAC tx success depends on

Answer 20

size

small OACs <2mm usually heal with normal blood clot formation and routine mucosal helaing

if large or lining torn - close with buccal advancement flap

Question 21

management of small OAC

5 points

Answer 21

Inform patient

Encourage clot

Suture margins pack has risk of pushing into sinus

Antibiotic (area of debate)

Post-op instructions most important
* Minimising pressure formation within the sinuses and mouth
* Avoid blowing nose, avoid sucking through straw, inflating balloon, smoking, avoid singing

Question 22

post op instructions for pt with OAC

Answer 22

Post-op instructions most important
* Minimising pressure formation within the sinuses and mouth
* Avoid blowing nose, avoid sucking through straw, inflating balloon, smoking, avoid singing

Question 23

post op instructions for pt with OAC

Answer 23

Post-op instructions most important
* Minimising pressure formation within the sinuses and mouth
* Avoid blowing nose, avoid sucking through straw, inflating balloon, smoking, avoid singing

Question 24

pts with OAF may complain of

6

Answer 24

• Problems with fluid consumption (fluids from nose)
• Problems with speech or singing (nasal quality)
• Problems playing brass/wind instruments
• Problems smoking cigarettes or using a straw
• Bad taste/odour/halitosis/pus discharge (post-nasal drip)
• Pain/sinusitis type symptoms (discussed later)

Question 25

management of OAF

Answer 25

excision of sinus tract (like a tube) raise Buccal Advancement Flap - same design as large OAC antral washout - not always done followed by same closure as OAC | chronic

Question 26

5 flap design options for OAC/OAF | 2 main

Answer 26

**Buccal Advancement Flap ** * most common, but can fail esp in bigger communication **Buccal Fat Pad with Buccal Advancement Flap** * thicker flap, can be better for larger communication * high in sulcus - yellow globular fatty tissue * 2 layer closure rather than 1, can cause more bruising and more prominent cheek bone on one side Palatal Flap *very painful, raw exposed bone on palate, thick tissue for flap coverage* Bone Graft/Collagen Membrane *usually only when others failed* *Rotated Tongue Flap (Historical)*

Question 27

aetiology of fracture of maxillary tuberosity | 5

Answer 27

* Single standing molar * Unknown unerupted molar or wisdom tooth * Pathological gemination/concrescence * Extracting in wrong order * Inadequate alveolar support with non-dominant hand Commonly involves maxillary sinus

Question 27

aetiology of fracture of maxillary tuberosity | 5

Answer 27

* Single standing molar * Unknown unerupted molar or wisdom tooth * Pathological gemination/concrescence * Extracting in wrong order * Inadequate alveolar support with non-dominant hand Commonly involves maxillary sinus

Question 28

dx of maxillary tuberoisty # | 4

Answer 28

noise movement notes both visually or with supporting fingers more than one tooth movement tear in soft tissue of palate

Question 29

management options for fracture of maxillary tuberoisty | 2 methods

Answer 29

Reduce and stabilise to tooth in front * Orthodontic buccal arch wire with composite * Arch bar * Splints (lab-made) – challenge as need impression Dissect out and close wound primarily * Pulled too far from blood supply so no chance healing

Question 30

if splint the tooth remember to | 5

Answer 30

Remove or treat pulp Ensure it is out of occlusion Consider antibiotic and antiseptics Post-op instructions * Similar to OAC instructions Remove the tooth surgically 4-8 weeks later after bone healing

Question 31

suspect root/tooth in maxillary sinus - what to do

Answer 31

Confirm radiographically by OPT, occlusal, or periapical (+/- CBCT usually on day of retrieval) Decision on retrieval * If in doubt or retrieval difficult – refer

Question 32

best outcome if part of tooth/root end up in maxillary antrum

Answer 32

fractured part of floor of antrum but not torn lining of antrum, but accidentally pushed root up so wedged between lining of maxillary antrum and alveolar bone * won’t cause sinusitis, pt issues or will move as wedged in place So if pt doesn’t consent to further surgery it is least likely to cause problems (cannot guarantee none)

Question 33

retrieval options for root/tooth in antrum | 3

Answer 33

OAF-type approach / through the extraction socket most common * Open fenestration with care * Suction – efficient and narrow bore * Small curettes - careful esp if think lining isn't breached yet * Irrigation or ribbon gauze * Close as for OAC Caldwell-Luc approach * Buccal/Labial sulcus * Buccal window cut in bone more anterior to where root is and look downwardly posterior into sinus ENT if unsuccessful or hard on radiograph * Endoscopic Retrieval

Question 34

when you examine pt with maxillary discomfort remeber

Answer 34

close relationship of sinuses and the posteiror maxillary teeth aetiology of paranasal sinus inflammation and infection **pt with sinusitis often present to the dentist first**

Question 35

aetiology of sinusitis

Answer 35

Most are precipitated by the effects of a **viral infection** *** Inflammation and oedema * Obstruction of ostia * Trapping of debris within sinus cavity** Mucociliary clearance patterns may be altered by: * Allergens * Inflammation * anatomic abnormalities Normal physiological function is further disrupted by the cellular damage that occurs to the mucosal lining, this affects normal ciliary function When the sinus can no longer evacuate its contents efficiently * build up of pressure, also produce an area of stagnation in sinuses * opportune situation for bacterial overgrowth of normal flora - leads to a bacterial infection –* opportunistic infection, viral initially*

Question 36

signs and symptoms of sinusitis

Answer 36

* Facial pain * Pressure * Congestion (fullness) * Nasal obstruction * Paranasal drainage * Hyposmia (reduced sense of smell) * Fever * Headache * Dental pain * Halitosis * Fatigue * Cough * Ear pain (referred pain) * Anaesthesia / paraesthesia over cheek

Question 37

dental causes to rule out is sinusitis suspected

Answer 37

periapical abscess periodontal infection deep caries recent extraction socket TMD neuralgia or atypical facial pain/chronic midfacial pain

Question 38

4 dental indicators for sinusitis

Answer 38

Discomfort on palpation of infraorbital region A diffuse pain in the maxillary teeth Equal sensitivity from percussion of multiple teeth in the same region * Doesn’t make sense all TTP as no evidence of dental disease Pain that worsens with head or facial movements

Question 39

3 tx aims for sinusitis

Answer 39

tx presenting symptoms reduce tissue oedema reverse obstruction of the ostia - allow drainage

Question 40

tx for sinusitis

Answer 40

Decongestants reduce mucosal oedema * Ephedrine nasal drops 0.5% one drop each nostril up to three times daily when required (use for a maximum of 7 days) * Effective but only short term use as cause atrophy of nasal lining Humidified air is also helpful (steam/menthol inhalations) *Antibiotics for sinusitis should only be used if symptomatic treatment is not effective/symptoms worsen AND signs and symptoms point to a bacterial sinusitis * Amoxicillin 500mg, three times a day, for 7 days (first line) OR * Doxycycline 100mg, once a day, for 7 days (200mg loading dose)* | check SDCEP guidance

Question 40

tx for sinusitis

Answer 40

Decongestants reduce mucosal oedema * Ephedrine nasal drops 0.5% one drop each nostril up to three times daily when required (use for a maximum of 7 days) * Effective but only short term use as cause atrophy of nasal lining Humidified air is also helpful (steam/menthol inhalations) *Antibiotics for sinusitis should only be used if symptomatic treatment is not effective/symptoms worsen AND signs and symptoms point to a bacterial sinusitis * Amoxicillin 500mg, three times a day, for 7 days (first line) OR * Doxycycline 100mg, once a day, for 7 days (200mg loading dose)* | check SDCEP guidance

Question 41

fungal infections sinusitis

Answer 41

very rare - if have a non-resolving sinusitis, check for this can cause expansion of the bony walls by increase mucus secretion and fungal growth (happens in any long standing sinus infection) * REFER TO ENT

Question 42

can trauma cause sinusitis

Answer 42

yes - by violating the integrity of the bony cavity and sinus membrane e.g. * Sinus wall fractures * Orbital floor fractures * Root canal therapy * Tooth extractions * Dental Implants/Sinus lifts (perforate sinus, reduce volume of max sinus to allow inc bony deposition for bone graft) * Deep periodontal treatment * Nasal packing * Nasogastric tubes * Mechanical (nasal) intubation

Question 43

possible traumas that can damage the sinus bony walls and membrane | can cause sinusitis 9

Answer 43

* Sinus wall fractures * Orbital floor fractures * Root canal therapy * Tooth extractions * Dental Implants/Sinus lifts (perforate sinus, reduce volume of max sinus to allow inc bony deposition for bone graft) * Deep periodontal treatment * Nasal packing * Nasogastric tubes * Mechanical (nasal) intubation

Question 44

benign sinus lesions

Answer 44

can be chance findings on OPT e.g. polyps, papillomas, antral pseudocysts, mucoceles and **mucous retention cysts** or odontogenic cysts/tumours expanding into maxillary sinus

Question 45

malignant lesions in maxillary sinus

Answer 45

rare primary tumous e.g. of the bone or lining or local spread from adjacent sites e.g. SCC of maxilla invades the sinus