Do not spit, saliva is beneficial
Dr H.S. Chawla

Normally, one views spit as something dirty. In fact, it is not so at all.

The spit that you know of is scientifically called “saliva”. It is produced by three major and many minor salivary glands located in and around your mouth. The one which is the largest is the “parotid gland”. It is located below the skin in front of your ears. This gland has an outlet, a duct, which opens inside your mouth opposite the first upper molar tooth on both sides of your cheeks.

The parotid saliva is secreted/poured into your mouth through this opening. The two other major glands are the sub-mandibular and sub-lingual salivary glands. These are positioned below your lower jaw. Their openings in your mouth are located below your tongue just lingual to the lower incisors.

Once the saliva is discharged into the mouth, the dribble from all the three salivary glands along with that from other minor salivary glands mixes together and makes a common pool. It spreads all over your mouth and bathes your teeth and the mucous membrane of the oral cavity.

Decreased production of saliva is known to predispose you to dental cavities. In fact, there are two components of salivary secretions, parameters that affect the health of your teeth: flow rate and viscosity of saliva. It has been seen that individuals/children with unfilled dental cavities have reduced flow as well as thick ropy saliva compared to the ones with no cavities. But as soon as the cavities are filled, both these parameters of saliva return back to normal.

Reduced secretion of saliva is also noticed in cases of individuals undergoing radiotherapy or chemotherapy for a malignant lesion located in and around oral cavity. In individuals undergoing this treatment a spurt in the development of new dental cavities is seen. To check this surge of the dental decay, the use of fluoride tooth paste three times a day along with the use of daily fluoride mouth rinses and six monthly professional topical application of fluoride is recommended.

The salivary secretions increase when you are eating and even just chewing. Sugar-free chewing gums, ones containing “xylitol”, are known to protect teeth against dental caries. One of the reasons is the increased secretion of saliva due to chewing. Mere thinking of a tasty food can also start the salivation into your mouth; your mouth can water even at the smell or just at the thought of food. The consumption of citrous/spicy items would trigger sumptuous formation of saliva.

The saliva contains digestive enzymes for food. It also lubricates food and helps in swallowing through your throat. Normal secretion of saliva is very essential. Therefore, it is necessary to chew food well so that enough saliva gets secreted and goes into your stomach to aid in the digestion of food.

When salivary secretions decrease, you get “dry mouth”. You would have experienced this dryness in a tense situation, like when you were to deliver a lecture or a speech, in situations of illness of a loved one, your own illness or appearing for an examination, etc. There are also a few diseases which are known to dramatically decrease the salivary flow rate. Certain medicines are also known to reduce the salivary secretions, particularly anti-histaminics that you take for controlling your runny nose or allergy. The salivary secretions naturally decrease as you age. Normal flow and consistency of saliva is essential for the upkeep of teeth. You are required to consult your physician or dentist in case you notice a constant marked decline in salivary secretions; it is treatable to an extent.

Bacteria, the main cause for dental diseases, stick on the teeth and form a biofilm. When you eat, particularly sugar containing items, its interaction with bacteria produces acid. This acid erodes the hard enamel of your teeth. Such demineralisation attacks on a tooth results in a cavity formation, the dental caries.

When you eat fibrous food items, the bacteria shed from teeth and fall into the saliva. The saliva also acts as a medium for the transportation of these planktonic bacteria within your mouth and also is a source of cross contamination between individuals.

Saliva also contains calcium, phosphate and a small amount of fluoride; it helps to remineralise the demineralisation that naturally happens whenever you eat, particularly the food items containing sugar. This is another protective mechanism against dental caries. So, saliva is health-giving. Take care, do not indulge in the habit of spiting.

The writer, a former Professor and Head, Oral Health Sciences Centre, PGI, Chandigarh, is Chief Consultant, SukhIqbal Dental Center, Chandigarh. Email: chawlahs@gmail.com

The truth about back pain
Dr Ravinder Chadha

LOW back pain afflicts most individuals at least once in their lifetime. The causes are numerous: bad/incorrect postures, wrong training techniques, forward bending while picking up some objects, etc. Aging alleviates disability as muscles become less flexible and weak.

The back comprises various structures like muscles/ligaments/bones/joints and discs which when injured or weakened could lead to back pain. There is also a great deal of overlapping of nerve supply to these structures. Pain due to a herniated disc can mimic a muscle or ligament injury. Therefore, a proper examination to diagnose the cause of the pain is critical to advise appropriate treatment. Myths and realities

• It is true that rest could facilitate recovery from acute injury by alleviating inflammation. Bed rest is a natural healer and routine physical activity/movements could irritate the spine aggravating the intensity of pain. But it’s a myth that one should remain in bed for a long time which can cause cardiovascular de-conditioning, loss of bone mass, weakening and atrophy of spinal muscles which are so important to stabilise the spine. However, the activities that aggravate pain like lifting heavy weights, twisting, sitting at a stretch for prolonged periods and driving should be avoided. Lying in bed for prolonged periods could cause depression.
• A prolapsed disc is the main reason for acute back pain is actually a myth — Only 5 per cent of low back pain cases result from slipped discs. Muscle spasm resulting from a simple back strain can lead to excruciating pain which may limit one’s ability to walk or even stand. On the other hand, a herniated disc could be absolutely painless.
• Sitting slouched in a chair could lay stress on the back resulting in pain — Similarly sitting up straight in one position for prolonged periods could also exert strain on the back. It is ideal to sit with the lower back touching the backrest of the chair and the spine needs to be straightened so that the head is balanced. The use of the lumbar roll above the belt line — in the hollow of the back — could help adapt to a correct posture. To avoid prolonged sitting, place an alarm clock at the corner of the room and put off the alarm after every 25 to 30 minutes.
• Lifting heavy weight always results in back pain is a myth — It’s not the weight but how one lifts is important. While lifting an object squatting close to the object with straight back, head up and standing up using the legs to lift the load facilitates painless lift. Do not twist or bend your body while lifting. However, it is advisable not to lift too heavy a weight.
• Most back problems eventually require surgery is a myth — Surgery is required as treatment for a traumatic injury or to remove tumours from the spine. For most back problems, non-surgical treatment, if rendered appropriately, is equally effective at relieving back pain and increasing mobility. Surgery should be the last resort after all other options have been exhausted.
• l Everyone with back pain will need an MRI is also incorrect — MRI is an extremely useful diagnosing test, yet it is not required in all back pain cases.
• Herniated discs require corrective back surgery — Most herniated discs are caused by unequal stress on the spine due to muscle imbalances and postural dysfunctions. Disc surgery only relieves the pressure on the spinal nerves, but other factors that force the disc herniation should also be corrected. Otherwise back pain can reoccur.
• Regular exercise prevents back pain — Back pain is most common among people who are overweight and undertake vigorous activity. Individuals who exercise and take care of themselves are less likely to have back pain. Exercises should be done according to the problem and not the routine exercises for the back which can aggravate pain. People suffering from an acute lower back pain are recommend a short period of rest, medicines, etc. Once the acute pain subsides, an exercise regimen may help prevent the recurrence of back pain.

The writer runs a pain management clinic in Chandigarh. E-mail: chadha_r2003@yahoo.co.in