How important is sinus in dentistry?
A toothache is one of the worst pain one can experience. This toothache can be confined to that particular region, or it can be a throbbing pain that can radiate to the head and jaw regions. This tooth pain as such is caused by main reasons, and some may be not even due to the tooth itself!! One of these can be due to a blocked sinus. If you suffer from chronic nasal congestion as well as toothaches, the two might be related, and this is a two-way relationship.
In a study conducted over a 5-year period, 198 patients with 244 affected sinuses fulfilled the proposed criteria. The incidence of chronic maxillary sinusitis in the population was 0.02%. A dental pain manifestation was found in 40.6% of the sinusitis cases. 
Like how a blocked sinus can cause tooth pain, so can an infected tooth cause sinusitis.10-12% of maxillary sinusitis are of odontogenic origin. 
How does it affect tooth pain?
A sinus is an air-filled cavity, which is located in the skull. It plays a very important role in conditioning the air that we breathe in before it reaches the lungs. The sinus is lined by a membrane, which acts as a hub of both healthy and harmful microorganisms.
There are 4 sinuses seen in the skull namely the frontal, ethmoidal, sphenoidal and maxillary air sinuses. When dentistry is concerned, the important relationship is seen with the maxillary air sinus. This is to the discrete placement of the sinus in the upper jaw and the roots of the upper molar teeth being related to this sinus.
The sinus is lined by a membrane. This membrane can become inflamed and infected. If this happens, it can block the nasal passage, and the passage can become packed with mucous. The bacteria which is now trapped in the sinus will multiply and cause an infection. Pain and bad taste in the mouth is the sequel to this.
If you have an infection in your maxillary sinus, pressure starts to build and then it presses down on your jaw bones.
Since the upper back teeth are the ones close to the sinus, they are the ones usually affected and cause a sinus toothache.
The cause of the pain? It is the roots of the upper first molar teeth and since they lie to close the sinus floor, or sometimes even extending inside them. The nerves of the roots will be affected by the swelling and pressure. Even though our teeth might be in good health, we will experience sensitive teeth. This is a sinus toothache, and it can be very painful. The longer the sinus block is left untreated, greater the pain.
Symptoms and Management of sinusitis :
One of the classical symptoms to recognize sinus infection causing toothache is pain that is experienced in the tooth when you bend down. This occurs due to shifting of pressure in the sinus. The sinus, jaw and nasal area tend to feel sore and painful too. A headache too can be usually associated with sinusitis and tooth pain. Typically a sinus caused a toothache disappears once the sinusitis is treated and a tooth disease-causing sinusitis disappears once the offending tooth is treated.
There are certain home remedies that one can attempt to do, to manage the symptoms. Flush your nasal passages, take multiple steam inhalation sessions in a day to reduce the soreness and heaviness in the face. Keeping the body hydrated is also of uttermost importance and stick to a hot meal plan through the period of sickness.
If the home care management fails to subsidize your symptoms, visits the Dentist and the ENT to rule out potential complications. Management would include starting on a first line management of antibiotics such as Amoxicillin or Augmentin. Once the underlying pathology has been treated, the other manifestations tend to subside.
As the name suggests [ORO-Oral cavity, ANTRUM-Sinus, FISTULA-]
An epithelium-lined pathologic tract] an oroantral fistula is an abnormal communication between the sinus and the oral cavity.
It can be due to various reasons. One of the main reasons for such fistula formation is an infection near the end region of the root, especially the upper first and second molars. The infection proceeds onto form a communication between the teeth and sinus.
The oro-antral fistula can be detected using various methods. A thorough examination intraorally using the mouth mirror is usually carried out to detect the fistula. Treatment would be that when the doctors would prescribe a mouth rinse and a course of antibiotics. Surgery will be indicated in the later stages to remove the fistula.
IMPORTANCE OF MAXILLARY SINUS IN DENTAL IMPLANTOLOGY:
The success of fixed prosthetics like dental implants mainly relies on the quality and quantity of bone at the implant site. So when implants are planned in the upper back tooth, especially the upper molar region, the maxillary sinus plays a pivotal role.
This is mainly due to the position of the maxillary sinus near the roots of the upper molar teeth. When the level of the sinus comes down due to various reasons such as prolonged nonreplacement of teeth, aging etc, the height of the available bone for implant placement becomes less viz., less than 10 mm. Hence comes the need for a procedure called
‘SINUS LIFT SURGERY’
TYPES OF SINUS LIFT SURGERY- Performing a sinus life surgery is as important as placing a dental implant. Following a thorough diagnostic examination and various confirmatory tests, a conclusion will be drawn as to which method of sinus lift is to be performed. Each of the techniques has its indications and contraindications and must be performed strictly in accordance with them.
There are mainly two types of sinus lift surgeries
I) Direct sinus lift- Direct sinus lift is mainly indicated when the bone height is very less. It involves making a small window in the wall of the sinus and packing the sinus with a bone graft material. This usually has a longer healing period and immediate placement of implant would be difficult. Since the height of the bone is minimal, it requires from 4 to 6 months for healing and bone regeneration after the sinus lift procedure
II) Indirect sinus lift- This procedure can be indicated in cases where there is a moderate level of bone present (7-8mm). The sinus is approached from the crest of the alveolar ridge and an osteotome is used. This is a less invasive procedure and has a shorter healing time and waiting period. This is usually a ‘one step procedure’ were implant can be placed on the same day as the sinus lift.
If implants are placed simultaneously with the sinus lift procedure and the process of loading should be increased gradually. It will allow the bone to recover and regenerate after grafting. The patient should be under regular medical supervision in the postoperative period.
Sinus lift surgery proves to be a very important aid for successful implant placement. A study was done to evaluate the success rate of sinus lift assisted implant surgery. A success rate for dental implants in the sinus lifts reached 95.2% after a period of 24 months of evaluation. 
COMPLICATIONS OF SINUS LIFT SURGERY:
Success and failure are two sides of the same coin. Complications are possible, regardless of the technique. A study was conducted were a group of 45 patients in whom a sinus lift procedure had been performed was evaluated for sinus pathology 12 to 60 months after bone transplantation and implant insertion, using a questionnaire, conventional radiographic examination, and nasoendoscopy and postoperative maxillary sinusitis was detected in two of five patients with a predisposition for sinusitis, but in none of the other 40 patients. The occurrence of iatrogenic sinus membrane perforations during surgery was not related to the development of postoperative sinusitis in patients with healthy sinuses. 
But these complications can only arise as a result of poor dental implant hygiene or non-observance of certain restrictions given by the doctor after the sinus lift procedure.
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