Long Root Tooth Infection: Maxillary Sinusitis
Another common pathway for a tooth infection in teeth with long roots, is to spread into the maxillary sinus through its palatal root.
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There are four paranasal sinuses. Paranasal sinuses are mucus lined cavities within the cranium that drain into the nasal cavity. The paranasal sinuses include:
- Frontal sinus
- Ethmoid sinus
- Maxillary sinus
- Sphenoid sinus
The Maxillary sinus is the largest sinus of the four; it has six walls and is "pyramidal shaped", positioned laterally to the nasal cavity (Whyte and Boeddinghaus, 2019). it is also the one with the closest contact with the apex of maxillary teeth and so the most at risk of this infection pathway. (Whyte, Boeddinghaus, 2019)
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SYMPTOMS OF MAXILLARY SINUSITIS:
- nasal involvement or obstruction
- headaches
- swelling around the front of the face. These symptoms are usually limited only the affected side of the face.
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(NIAID, 2011)
Maxillary Sinusitis Infection Pathway Stages
Stage 1: Healthy tooth
The image above shows a healthy cross section of a long apex tooth.
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Stage 2: Initial Infection
During the initial stages of the tooth infection, the healthy tooth gets invaded by bacteria contained in plaque, which thrive off the carbohydrates in the mouth and produce acid, which slowly destroys the enamel layer.
Stage 3: Invasion of the Pulp Chamber
When the bacteria gain access to the dentine, they invade the dentinal tubules and in this way gain access to the pulp chamber in the middle of the tooth. Within the pulp chamber, the bacteria incite an acute inflammatory reaction which causes an increase in the hydrostatic pressure within the tooth and leads to hypoxia and this leads to destruction of the contents of the pulp and roots canal system, effectively killing the tooth.
Stage Four: Spread into the Maxillary Sinus
If the root of the tooth is long, or it may in some instances be physically within the maxillary sinus the infection does not have to erode any bone barriers to spread into the maxillary sinus and instead has a direct passage in. The teeth most commonly within the maxillary sinus include the 1st, 2nd and 3rd molars. It is usually the palatal root of an upper molar that involves the sinus.
This infection spread can lead to nasal involvement or obstruction, headaches and swelling around the front of the face. These symptoms are usually limited only the affected side of the face. This infection is treated by removal of the infective focus by extraction which allows pus to drain through the tooth socket. If the tooth is to be saved, then removal of the dead contents of the root canal and pulp chamber by an endodontic root treatment. Conventionally the sinus is allowed to drain through its ostium and this is increased by methanol inhalations, it is not necessary to increase drainage by performing a lateral nasal osteotomy.
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