maxillary sinus Flashcards
Describe the formation of maxillary sinus during embry.
The maxillary sinus forms during the 3rd and 4th fetal months and is relatively large at birth.
What are the functions of the paranasal sinuses?
Gives resonance to the voice
Serves as reserve chambers for warming inspired air
Reduces the weight of the skull
Define the maxillary sinus.
The maxillary sinus, also known as the maxillary antrum, is the largest of the sinuses and is a pyramid-shaped cavity within the bone of the maxilla
How is the opening of the maxillary sinus (ostium) located and what lines it?
Located superiorly on the medial wall of the sinus and is lined with mucosa.
What can happen to the opening of the maxillary sinus during episodes of inflammation or disease?
The opening of the maxillary sinus can become narrow or blocked during episodes of inflammation or disease
What can be found on the posterior wall of the maxillary sinus cavity?
The alveolar canals that transport the posterior superior alveolar blood vessels and nerves to the maxillary posterior teeth
What can happen to the roots of maxillary molars and premolars in relation to the maxillary sinus?
The roots of maxillary molars and sometimes premolars may project into the floor of the maxillary sinus and can perforate the bone, with only the mucosal lining of the sinus covering them.
Describe the steps involved in closing an oroantral fistula (OAF).
Create a 3 sided flap, 2 relieving incisions and 1 crestal incision
Raise the flap
Trim the buccal bone if necessary
Incise the periosteum
Check the flap can be brought across the defect tension free
Suture.
What are the common complaints of patients with chronic OAF?
Problems with speech or singing (nasal quality)
Difficulties playing brass or wind instruments
Problems smoking cigarettes or using a straw
Bad taste/pus discharge (post-nasal drip)
Pain/sinusitis type symptoms.
What are the flap design options for closing an oroantral communication (OAC) or OAF?
Buccal advancement flap (most common)
Buccal fat pad with buccal advancement flap
Palatal flap
Bone graft/collagen membrane
Rotated tongue flap (historical).
What are the possible causes of maxillary tuberosity fracture?
Single standing upper molar being extracted
Unknown unerupted molar or wisdom tooth
Pathological gemination/concrescence
Extraction in the wrong order
Inadequate alveolar support.
How can a fractured maxillary tuberosity be managed?
Stop the extraction
Reduce and stabilise the fracture using orthodontic buccal arch wire with composite, arch bar, or splints (lab made),
Dissect out and close the wound primarily.
What should be considered when splinting a tooth after a maxillary tuberosity fracture?
Remove or treat the pulp
Ensure it is out of occlusion
Consider antibiotics and antiseptics
Give post-operative instructions
Plan for surgical removal of the tooth 4-8 weeks later.
How can a root or tooth in the maxillary sinus be retrieved?
Through an OAF type approach, which involves open fenestration, suction, small curettes, irrigation or ribbon gauze, and closure as for OAC
Caldwell-Luc approach can be used with an incision in the buccal/labial sulcus and a buccal window cut in the bone.
Referral to an ENT specialist for endoscopic retrieval may be necessary.
Name 4 common signs and symptoms of sinusitis?
Facial pain
Pressure
Congestion
Nasal obstruction
Paranasal drainage
Hyposmia (reduced sense of smell)
Fever
Headache
Dental pain
Halitosis, fatigue
Cough
Ear pain
Anesthesia/paresthesia over the cheek.
What are some indicators of sinusitis that differentiate it from dental causes of maxillary discomfort?
Discomfort on palpation of the infraorbital region
Diffuse pain in the maxillary teeth
Equal sensitivity from percussion of multiple teeth in the same region
Pain that worsens with head or facial movements.
Describe the recommended dosage for nasal drops in the treatment of sinusitis.
Ephedrine 5% one drop each nostril up to 3 times daily (use for a max of 7 days)
When should antibiotics be used for sinusitis?
When symptomatic treatment is not effective or symptoms worsen and signs and symptoms point to a bacterial sinusitis
What are the recommended antibiotics for treating bacterial sinusitis?
Amoxicillin 500mg three times a day for 7 days or doxycycline 100mg once a day for 7 days (200mg loading dose)
What is the purpose of using humidified air in the treatment of sinusitis?
To provide relief and alleviate symptoms
How can a non-resolving sinusitis be caused by a fungal infection?
Increased mucus secretion and fungal growth can cause expansion of the bony walls
List three types of trauma that can cause sinusitis.
Sinus wall fractures
Orbital floor fractures
Root canal therapy
Name 4 benign sinus lesions.
Polyps
Papillomas
Mucoceles
Mucous retention cysts
What are the two categories of malignant sinus lesions?
Primary tumours
Local spreads from adjacent sites
