Humans have about 12 cavities in the facial bones, which are located on the upper and lateral sides of the nasal cavity, called the paranasal sinuses. If the cavities or paranasal sinuses are inflamed, they are called sinusitis. The occurrence of sinusitis is generally accompanied or triggered by rhinitis, so sinusitis is often also called rhinosinusitis.

Anatomy Sinus
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The name of these sinuses is based on the facial bones in which they are located.
a. axillary sinuses (the largest sinuses) are located in the maxillary bone (under the eyes) and innervated by the trigeminal nerve.
b. frontal sinuses are located in the frontal bone (superior to the eyes) and innervated by the trigeminal nerve. These sinuses form the hard part of the forehead.
c. ethmoidal sinuses are located ethmoid bone and innervated by the ethmoidal nerves.
d. sphenoidal sinuses, located in the sphenoid bone and innervated by the trigeminal nerve.

All sinuses are covered by modified respiratory epithelium, which is capable of producing mucus and ciliated. The secretions produced are channeled into the nasal cavities. In healthy people, the sinuses mainly contain air.

What are the Sinuses Functions?

Mainly, they work to produce a mucus that moisturizes the inside of the nose. This mucus layer protects the nose from pollutants, micro-organisms, dust, and dirt. They might contribute to:
1. forming facial growth.
2. Facial air conditioning,
3. Reduce the weight of the skull.
4. sound resonance


What is Sinusitis?

Sinusitis is an inflammation of paranasal sinuses. Sinusitis can occur in one or several of the four sinuses (maxillary, ethmoidal, frontalis, and sphenoidal). When all paranasal sinuses become inflamed, they are called pansinusitis.

Sinusitis can be divided based on:
a. anatomical location (maxillary sinus, frontalis, ethmoid, and sphenoidal),
b. causative organisms (viruses, bacteria, and fungi),
c. clinic

  • acute sinusitis (symptoms last from a few days to 4 weeks)
  • subacute sinusitis (lasting more than 4 weeks but less than 3 months) s
  • chronic sinusitis (if more than 3 months).

Based on the cause sinusitis is divided into:
1. Rhinogenic (caused by abnormalities or problems in the nose).
Everything that obstructs the nose can cause sinusitis, such as acute rhinitis (influenza), polyps, and septum deviation.
2. Odontogenic (caused by dental abnormalities)
The most common cause is the infection of the upper molars (premolar and molar). The bacterial causes are Streptococcus pneumonia, Hemophilus influenza, Steptococcusviridans, Staphylococcus aureus, Branchamella catarrhalis.


What are the Causes of Sinusitis?

Various infectious and noninfectious factors can contribute to the occurrence of acute obstruction in the sinus cavity or disruption of fluid secretion by cilia, which ultimately causes sinusitis.

1. Infectious
a. Virus
Viruses cause most sinuses infections. Viral particles attach to the nasal mucosa, which disrupts the mucociliary system. The virus penetrates the mucous palate, then into cells, and infects quickly. Viruses that cause sinusitis include rhinoviruses, influenza types 1 and 2, and respiratory syncytial virus.

b. Bacteria
Organisms that often cause acute sinusitis are Streptococcus pneumonia, Haemophilus Influenzae, Branhamella catarrhalis, Streptococcus alfa, Staphylococcus aureus, and Group A Streptococcus.

2. Noninfectious
a. Allergic reaction
Allergies react in the airways and sinus cavities that cause edema and inflammation of the mucous membranes. This edema and inflammation cause blockage of the sinus cavity, making it an ideal place for the proliferation of fungi, bacteria, or viruses.

Allergy can also be one of the predisposing factors for infection caused by mucosal edema and hypersecretion. Swelling of the sinus mucosa can clog the mouth of the sinus and interfere with drainage. This blockage causes infection resulting in surface epithelial damage. If this cycle continues, then it can become chronic sinusitis.

b. Neoplasma
Neoplasms such as nasal tumors or sinus tumors (squamous cell carcinoma), and granulomatous disease (Wegener’s granulomatosis or rhinoscleroma) can also cause Sinus Ostia obstruction.

c. Fungi
The fungus can also cause sinusitis in patients with immune system disorders, which indicate a life-threatening invasive infection. Fungi that cause infections include Rhizopus, Rhizomucor, Mucor, Absidia, Cunninghamella, Aspergillus, and Fusarium species.