Paranasal sinuses Flashcards
Basic anatomy of Maxillary sinus
Base - lateral wall of the nose
Post wall - Infra temporal surface of the maxilla
Roof - Thin orbital plate of the maxilla
Anterior wall - Facial surface of maxilla
Floor - Roof of the alveolar process and overlies molar root apices
and the apex extends lateral into zygomatic process of the maxilla
The maxillary sinus is lined by the…?
Scneiderian membrane that consists of ciliated epithelium on the inside and periosteum on the bony side
What is the nerve supply to the maxillary sinus
Anterior,middle and posterior superior alveolar nerves
Blood supply to the maxillary sinus include the venous drainage
Super alveolar branches from maxillary artery
Greater palatine
Venous drainage - pterygoid venous plexus
Secretion drainage of maxillary sinus
Ostium in middle meatus
High on medial wall of sinus
Cilia around ostium remove secretions
How can we clincally examine the MX. sinus?
Visual inspection of face and intral oral vestibule for swelling or redness.
Nasal discharge.
External tapping of anterior wall over cheek prominence.
Intra-oral palpation between canine fossa and zygomatic buttress.
Patient complains of dental pain or pain to percussion on multiple post teeth.
Transillumination.
A normal sinus on a radiograph should appear?
Radiolucent with no thickening of the mucosa and outlined by well demarcated cortical bone.
Comparison between sides are helpful
How can you determine if a patient has sinusities?
If mucus drains through the sinus ostium - it is not sinusitis
retention of mucus, local pain and even headache
A few factors which contribute to development of sinusitis
Acute rhinitis which spreads thorugh the ostium
Diving or swimming in polluted water
Tooth abscess adjacent to the mx. sinus
Mid face fractures
Predisposing factors
- Air polluttion
- Malnutrition
- Physical exhaustion
Local symptoms of acute Mx. sinusitis
Severe local pain behind the eye or superior to affected maxillary sinus.
Swelling of inferior eyelid.
Hard, enlarged swelling over the zygomatic bone can indicate a sinus neoplasm.
Pain and pressure sensitivity on all maxillary teeth which are adjacent to the sinus
Post-nasal drip discharge
What is an oro-antral communication and Antro-oral fistula ?
A fresh antro-oral opening is a new opening between the oral cavity and maxillary sinus where epithelialization of the opening has not taken place.
An antro-oral opening fistula is an opening between the oral cavity and the maxillary sinus where epithelialization has taken place.
To ensure we make an accurate diagnosis and treat the patient adequately, what precautions should we take?
Quality radiographs should be taken.
Warn the patient of possible sinus involvement.
Apply surgical principles especially minimal damage to tissue.
Dont use cryer technique if tubersity posteriorly is > 3mm.
How can we examine for antro0oral openings?
Examine the extracted tooth
X-ray
Clinical observations
Valsalva manoeuvre
Small antra oral opening is defined as…?
an opening that is less than 3-4mm
no infection present
no epithelization
Should heal spontaneously
Bigger antral oral opening is defined as…? ( with sinus membrane present )
More than 5mm
No infection present
No epithelization
Proper blood clot formation and post op instructions
