Practically every week of the year at Cape Dental Care we will have someone come in with a toothache that ends up being diagnosed sinusitis. Their symptoms include:
- Sore upper posterior teeth (percussion, usually more than one)
- Feeling sensitive/swollen to the touch on their cheek
- Stuffy nose (runny nose, possibly green or yellow discharge)
- Post nasal drip (halitosis)
- History of recent upper respiratory infection
- Maxillary sinuses – They are by far the largest paranasal sinuses in the body. They are golf ball size boney air pockets found in the cheek area. They are believed to serve several purposes including to help warm and humidify the air entering your lungs, add pitch to your voice, lighten the head so it is easier to juggle on top of your spine, and absorb trauma to the face to protect the brain and eyes. Having the maxillary sinus directly below the eye socket protects the eye from being crushed in an accident. Instead, the eyeball can be forced into the maxillary sinus relatively undamaged (blow-out fracture of the eye). This is why the eye can hurt with a maxillary sinus infection.
- Frontal sinuses – These sinuses are above the eyeballs and when infected can give you a forehead headache.
- Ethmoid sinuses – They are usually referred to as the ethmoid air cells and are divided into anterior, middle and posterior air cells. They are located between the eye sockets and the nasal cavity. Another reason why the eyes hurt with ethmoid sinus infections.
- Sphenoid sinuses – They are located far back in the nasal cavity and are closely associated with the base of the brain (pituitary gland) superiorly and the nasopharynx inferiorly. Problems with these sinuses are difficult to diagnoses and treat.
- Mastoid air cells – Although not categorized as paranasal sinuses nor have the same functions, they are air fill chambers in the head that can become infected and cause considerable discomfort and morbidity. They are an interesting group of cavities in the temporal bones (around the ears) that fill with air shortly after birth through the eustachian tube via the middle ear. The normal function of these air cells are to aide in the normal functioning of the middle ear and vibration of the eardrum. They offer a reserve air supply to protect the eardrum from barotrauma and provides slow moving secretions that flush out the middle ear debris through the eustachian tube and out into the nose.
- Viral– This is usually of sudden onset and may last for up to a month. There is no other treatment than hydration, irrigation, and to treat the symptoms like you have a cold or flu. Antibiotics will not help this type of infection. Usually occurs after an upper respiratory infection. Unfortunately, most physicians/nurse practitioners and dentists improperly prescribe antibiotics as a first line treatment.
- Bacterial – This uncommon infection is a slower onset infection and may progress into chronic sinusitis. Fortunately, this infection responds well to various antibiotics (see below).
- Seasonal– This is our most common type of sinusitis. It can be caused by what you breathe in during the day like mold and pollen. Allergies are commonly accompanied with blocked/swollen sinuses. Can be exacerbated by a deviated septum and/or polyps. Consult an allergist/ENT.
- Fungal – This is a very difficult type of infection to treat and can last for many months or years. It is generally classified as allergic fungal sinusitis, acute invasive sinusitis, chronic invasive sinusitis, chronic granulomatous sinusitis, and sinus mycetoma. Fungal infections may develop in patients with poorly controlled diabetics or immunocompromised (leukemia, lymphoma, multiple myeloma, chemotherapy and AIDS). Diagnoses is usually made by a biopsy of the intranasal tissue. Treated with aggressive paranasal surgery is the primary treatment of choice. Anti-fungal drugs such as amphotericin B (1-1.5 mg/kg/d) are used if the fungal infection becomes invasive and moves from the sinus cavity to the adjacent deeper tissues. However, due to the unfavorable long term prognosis and limited treatment options, better therapeutic strategies are currently being explored such as a combination of surgery and a new anti-fungal drug called voriconazole.
- Polyps– Blockage or filling normal sinus structures with diseased tissue. Diagnosed with CAT Scan. Treatment: surgery.
- Deviated septum – This is where the center nasal bone is crooked and doesn’t allow the air to flow unhindered through the nasal passages.
- Irritants– Smoking, air pollution, noxious vapors. Remember smoking while driving in a car with children can be considered child abuse.
- Foreign object – Children can put the darndest things up their nose. Food inside the nasal passages eventually decay and can trigger a foreign body response which could include swelling, purulence and secondary infections.
- Airplane flight – If you are unfortunate to fly when experiencing a cold or sinus infection, you may have a bad flight! Pressure equilibration between blocked paranasal passageways and the middle ear can be a painful experience. Nasal decongestants work well if taken properly. Not taking enough may allow the congestion to return before the flight is over and defeat the purpose of taking medications in the first place (rebound rhinorrhea). Another interesting phenomenon occurs at high cruising altitudes. At sea level the body is not crushed by the weight of the atmosphere because of the sum of partial pressure gases dissolved inside of our bodies counteract the weight of the over head atmosphere (15 pounds per square inch). However, during high altitude flights the pressure of the cabin is approximately ½ that of sea level. That means air has to rush out of the paranasal sinuses and middle ear’s eustachian tube during ascent so the pressure would not cause discomfort. Recycled air inside pressurized cabins is not very pure (dust, body odor, perfumes, coughing/sneezing residue/germs, flatus, dry humidity) and can irritate many passenger’s sinus membranes. On descent, the air now has to rush back into the paranasal sinuses and eustachian tube or a vacuum sinusitis and/or middle ear pain will begin to form. The vacuum will draw transudate from the mucous membranes and fill the sinuses and middle ear causing congestion and possible infection for several days post-flight. (See Vacuum Sinusitis below)
- Wash hands frequently
- Avoid cigarette smoke (second hand too!)
- Be on the lookout for sick looking friends and family (no kissing, hugging or shaking hands – sorry)
- Clean house filters and humidifiers. Houses today are made like ice chests. Very little air exchange with the outside world is a key to energy conservation, but could be a recipe for runny noses. Stale air, dust mites, cooking exhaust, and other occupants contagions can be difficult to avoid if the air conditioner’s air circulation is hindered by dirty filters. Likewise, if you do not clean out old water leftover from the humidifiers, unwanted bacteria/fungus can accumulate and become a chronic source of irritation to the nasal passages.
- Keep up with the families vaccinations
- Drink plenty of fluids. This increases the fluids in your bloodstream and moistens the phlegm inside your nose/sinuses.
- Humidification: Increasing the humidity in the room will help moisten the phlegm inside your nose as well. Hot baths/showers will provide much relief from sinus congestion. Over-the-counter humidifiers work well if the house is equipped with an air conditioning system that will allow high humidity, otherwise the moisture will be continually removed by the condensator of the air conditioner. Tenting a small environment or shutting the bathroom door and running the hot shower may work better.
- Over-the-counter (OTC) remedies work well. Antihistamines and decongestants can relieve symptoms of cold/flu, but can leave you with side effects of rebound runny nose, wired or sleepy days and sleepless night. Some people can actually become addicted to nasal sprays. This is when someone has to use a nasal spray several times a day to clear their sinuses/nasal passages in the absences of an infection/irritant. This is called rebound rhinorrhea. The only cure for this addiction is cold turkey. This will result in days of a stopped up nose, but it will soon resolve and breathing will return to normal unless their is a physical obstruction that is hindering your breathing. In this is the case, consult your physician.
- Nasal Irrigation: This is the best kept secret to treating sinusitis. Flushing out the accumulated days nasal filtration is the key to good sinus health. Not only does it flush out pollen, dust, dirt, molds, chemicals, occupational/recreational airborne particulate and environmental pollutants, but it also removes leftover nasal prescription/OTC spray residue. This should become as ritualistic as brushing and flossing your teeth and using xylitol sugar at bedtime. Neti pots and squeeze bottle irrigators are sold at every pharmacy in the USA. Use as directed. Neti pots are harder to use and squeeze bottles can create too much force if not careful. Too much force can push saline solution into the eustachian tubes and possibly push an infection into the middle ear.
- Always consult your physician if the congestion lasts more than a week and/or a fever greater than 100℉.
Acute sinusitis usually follows a recent upper respiratory infection (rhinitis, flu, common cold). This infection can be either bacterial or viral. Infection can affect the upper airway passageways and the associated swelling can occlude the openings to the various sinus cavities. Blocking off a sinus cavity can cause a painful condition called vacuum sinusitis. This is a condition where the oxygen inside the trapped air, inside the blocked sinus, is absorb into the surrounding blood vessel filled mucous membranes. This resulting negative pressure can be intolerable. If the negative pressure is sustained over a period of time, then it may pull fluid from the mucous membrane subsequently filling the sinus with a transudate liquid that is a good bacteria growth media. The body will respond to any sinus infection by pouring into the sinus compartment white blood cells (leukocytes) and other blood products to fight the infection. The resulting cellulitis/infection creates positive pressure inside the sinus, edema and pain. If tooth nerves are flowing through the infected sinus area, they will enviably be affected. Going to your dentist to differentiate between an actual toothache and a sinusitis is a good way to begin the treatment for this condition. The dentist will see no abscess and a “whited-out” sinus and refer you to your primary care physician or an ENT if you do not currently have a physician.
In about 25% of the cases of maxillary sinusitis the cause is from a tooth borne infection. When bacteria invades the inner pulp chamber of a tooth an infection ensues. The cardinal signs of an infection include: pain, redness, heat and swelling. The tooth’s pulp chamber is known as a solid terminal blood supply. This means blood vessels only go in and out of a small area at the apex of the tooth’s root. In additions, the inside of the tooth is solid as a rock. Meaning it will not allow for any swelling at all. When bacteria enter the pulp chamber (decay, trauma, periodontal disease, crack) and swelling ensues, there is no place for the swelling to expand. Thus the blood coming in gets backed up by the swelling and cannot flow out. If no more blood can flow freely into the inside of the tooth then no more oxygen. If no oxygen, then the pulp tissue inside of the tooth dies. This dead tissue inside the pulp chamber is a good bacterial growth media. Bacteria grow to large numbers before pushing out the tip of the tooth to cause what is seen on the dental radiograph as an abscess. The tips of the upper back teeth are in very close association with the maxillary sinus. In some cases the infection from a tooth can spill over into the sinus causing a sinus infection. The treatment for this type of sinusitis is either a root canal or extraction.
(Always consult your physician before treating a sinusitis lasting more than 1 week and fever of >100℉)
Vacuum Sinusitis (acute): Nasal irrigation, decongestants, nasal sprays. Definitive diagnosis is made by an in-office antroscopy. Surgical treatment is a middle or inferior meatal antrostomy which is basically opening another hole into the maxillary sinus to relieve the vacuum.
Viral Sinusitis: Nasal irrigation, cold and flu OTC medications
Bacterial Sinusitis (pressure): Antibiotics are now being questioned as an appropriate primary treatment for sinusitis.
Primary therapy: Amoxicillin 500mg PO q8hr X 10 days with or without clavulanate. If allergic to penicillin then erythromycin 250mg PO q6hr X 10 days or trimethoprim/sulfamethoxazole 80/400mg PO q6hr X 10 days.
Second-line therapy: Cefuroxime 500mg PO q12hr X 10 days or moxiflorxacin 400mg PO qd X 10 days.
Pediatric note: Do not use fluoroquinolones due to concerns of premature epiphyseal growth plate closure (stunted growth of long bones).
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